Review 2
Serum K levels in diabetic ketoacidosis
Increased extracellular K, decreased intracellular K (insulin causes K to move intracellularly)
Wernicke's aphasia involves which part of the brain?
Left posterior superior temporal lobe (peri-sylvian)
Is the ejection fraction normal/increased/decreased in Dilated Cardiomyopathy?
Reduced (because systolic failure)
What lymph node drains the scrotum?
superficial inguinal
Acute Tubular Necrosis: 1) BUN/Cr 2) Fractional Excretion of Na 3) Urine Osmolality 4) Microscopy
1 = ~10-15 2 = > 2% 3= ~300 mOsm 4 = Muddy Brown Casts
How does bone density relate to BMI?
Bone density is proportional to BMI. --> BMI <22 kg/m2 (or weight <57.6 kg [127 lb]) is associated with *increased* risk for osteoporosis.
Which esophagitis has the following microscopic findings: Linear ulcerations
CMV Intranuclear & cytoplasmic inclusions
CD4 < 50
CMV (retinitis) Mycobacterium avium - Non-specific sxs (fever, night sweats, weight loss) or focal lymphadenitis - Usually CD4 < 50
______ is the number of epitope binding sites on each antibody. IgM antibodies have 10 valence sites, and IgG antibodies have 2.
Valency
*Latex agglutination* test detects *polysaccharide capsular antigen* of ...
cryptococcus neoformans - Cryptococcus neoformans causes meningoencephalitis in patients with untreated AIDS. Diagnosis can be made by detecting the polysaccharide capsule in cerebrospinal fluid using the latex agglutination test. India ink staining of cerebrospinal fluid is also used for diagnosis and can demonstrate round or oval budding yeast.
Patients diagnosed with _______ disorder experience at least 2 years of numerous periods of hypomanic and depressive symptoms that do not meet the criteria for hypomanic or major depressive episodes.
cyclothymic
Vitamin K is necessary for the carboxylation and functionality of coagulation factors II, VII, IX, and X. Newborns who do not receive prophylactic supplementation are at risk for bleeding complications. Patients with _______ are also at risk for vitamin K deficiency due to poor absorption of fat-soluble vitamins.
cystic fibrosis - Infants are born with low vitamin K stores due to poor transplacental transfer. Their livers are unable to use vitamin K efficiently and breast milk is low in this vitamin. Additional risk factors for neonatal vitamin K deficiency include parental refusal of vitamin K prophylaxis at birth and exclusive breastfeeding - Vitamin K deficiency can result in a life-threatening bleeding diathesis, such as intracranial hemorrhage and profuse bleeding from the gastrointestinal tract, umbilicus, and surgical sites. Deficiency is prevented by intramuscular supplementation at birth.
Programmed-death receptor 1 (PD-1) is a checkpoint inhibitor that downregulates the ______ response. Neoplastic cells often exploit this receptor via the overexpression of PD-1 ligand. An example of a PD-1 receptor inhibitors is _______
cytotoxic T-cell Pembrolizumab - restores the T-cell response, allowing cytotoxic T cells to invade the tumor and induce apoptosis of neoplastic cells.
The _______ functions as the primary site of ribosome synthesis and assembly.
nucleolus - All ribosomal RNA except 5S rRNA is transcribed in the nucleolus. - The large complexes containing both protein and RNA that are found freely floating and bound to the endoplasmic reticulum are most likely ribosomes. Ribosome biogenesis occurs primarily within the nucleolus, a dense round structure inside the nucleus that is in direct contact with the rest of the nucleoplasm. - The nucleolus contains ribosomal DNA coding for the 28S, 5.8S, and 18S ribosomal RNA (rRNA) components, and it is here where most of the rRNA is transcribed. After synthesis, rRNA is combined with ribosomal protein components that are translated in the cytoplasm and then imported into the nucleus. The immature 60S and 40S ribosomal subunits are then exported from the nucleus to fully mature in the cytoplasm.
The _______ houses the cell bodies of cholinergic neurons. In Alzheimer disease, these neurons secrete decreased amounts of acetylcholine.
nucleus basalis of Meynert
All veins in the developing embryo ultimately drain into the ______ , which drains into the primitive atrium of the developing heart.
sinus venosus
The _______ is an embryologic structure within the heart that receives blood from the vena cava. In adults, this structure forms the smooth portion of the right atrium, known as the sinus venarum.
sinus venosus
Surgical repair of an undescended testicle lodged in the inguinal canal involves moving the testis through the _______ and fixing it in the scrotum (ie, orchiopexy).
superficial inguinal ring
MOA of Doxorubicin and Daunorubicin (anthracyclines)
- binds with topoisomerase 2 to cleave DNA - binds with iron to generate free radicals
Medicare Part ____ covers inpatient hospital visits
A
The CFTR protein is a transmembrane ______-gated chloride channel
ATP
Hep Serologic Status: HBsAg, HBeAg, Anti-HBc IgM
Acute infection
________ is used to treat infections caused by Strongyloides stercoralis (strongyloidiasis) and Onchocerca volvulus (onchocerciasis)
Ivermectin
IgA dimers and IgM pentamers are linked by what?
J-chain
What drugs are dopamine agonists?
Bromocriptine Cabergoline
Medicare Part _____ as an optional capitated plan with additional benefits (vision, dental)
C
- vascular malformations commonly in brain parenchyma - increased risk for Intracerebral hemorrhage and Seizures
Cavernous hemangioma
Medicare Part _____ as an optional prescription drug plan
D
Doxorubicin has what adverse effect on the heart
Dilated cardiomyopathy
Which NRTI can cause pancreatitis?
Didanosine
Normal uterus size Retroverted uterus Chocolate cyst
Endometriosis - may see hemosiderin laden macrophages
What infections can cause membranous nephropathy
Hep B and C [also associated with Membranoproliferative] Syphillis SLE Tumors
_____ stimulates antibody isotype switching to IgE
IL-4
Hep Serologic Status: Anti-HBs
Immunized
Norovirus genome
Linear, non-enveloped, ssRNA
Borrelia burgdorferi causes
Lyme disease
Mutation in menin tumor suppressor is seen in
MEN 1 (2 hit hypothesis)
DOC for giardia, bacterial vaginosis, and trichomonas
Metronidazole
Eosinophilic intracytoplasmic inclusions are seen in which dermatology problem?
Molluscum contagiosum
What is used to treat carcinoid syndrome?
Octreotide (somatostatin analogue)
Fibrinoid degeneration of the vessel wall with luminal narrowing
PAN
- decreased tactile fremitus - decreased intensity of breath sounds - dullness to percussion
Pleural effusion
Cause of otitis externa
Pseudomonas
Hep Serologic Status: Anti-HBs, Anti-HBe, Anti-HBc IgG
Recovery
_______ presents with pink or purple plaques and papules. It is usually associated with severe pruritis and typically affects the volar surface of the wrists.
Lichen planus
PCOS patients are at increased risk for what?
endometrial hyperplasia/carcinoma
Osteocytes remained connected to each other via
gap junctions
Crohns disease can cause what kind of nephrolithiasis
hyperoxaluria
Diabetic peripheral neuropathy is due to degeneration of
large fiber sensory axons
what lymph node drains the testes?
para-aortic
Whats a common sign seen in acute Chagas (trypanosoma cruzi) infection?
swelling of eye
_______ = sudden inability to finish a thought
thought blocking
The ________ artery is the continuation of the internal iliac artery and runs inferiorly to supply blood to the gluteal muscles and a portion of the hip.
superior gluteal
*Add stroke syndromes*
x
What drugs are PPAR-gamma (not alpha) agonists? What is their effect?
"Glit" drugs: [increases insulin sensitivity like Metformin] - Pioglitazone - Rosiglitazone - Troglitazone (ban) MOA: - Activate PPAR-γ (a nuclear receptor) --> increase insulin sensitivity and levels of adiponectin --> regulation of glucose metabolism and fatty acid storage. - less potent vs sulfonylureas, metformin* - (UWORLD) pio ONLY:improves HDL, TG, LDL AE: - Weight gain, edema, HF, increase risk of fractures. Delayed onset of action (several weeks). - Rosiglitazone: increase risk of MI, cardiovascular death.
What Beta blockers are cardioselective?
"MAN BABE" (B1 = heart) - Metoprolol - Atenolol - Nabivolol - Bisoprolol - Acebutolol - Betaxolol - Esmolol - β1 adrenergic receptors are found in cardiac tissue and on renal juxtaglomerular cells, but not in vascular smooth muscle. - Selective blockade of the β1 receptor leads to decreased cAMP levels in cardiac and renal tissue without significantly affecting cAMP levels in vascular smooth muscle.
Men 2A (Sipple's Syndrome) symptoms
"Medullary" tumors - Medullary thyroid carcinoma - Pheochromocytoma (adrenal "medulla) Parathyroid adenoma
MEN 2B symptoms
"Medullary" tumors - Medullary thyroid carcinoma - Pheochromocytoma (adrenal "medulla) Mucosal neuromas Marfanoid Appearance
RBCs with a decreased surface area-to-volume ratio are seen in which conditions?
"Spherocytes": RBCs that lack central pallor [increased mean corpuscular hemoglobin concentration (MCHC) due to mild dehydration of RBC] - Hereditary spherocytosis - Autoimmune hemolytic anemia
The pleural fluid/serum lactate dehydrogenase ratio is _______ with transudative effusions.
*<0.6* - Glucose levels and leukocyte counts can suggest the degree of inflammation in a pleural effusion. - Because leukocytes metabolize glucose, highly inflammatory effusions typically have low glucose levels. - Transudative effusions are *not* inflammatory and almost always have low nucleated cell counts and normal (or high) glucose levels (~90 mg/dL)
Ewings sarcoma involves what part of the bone
*Diaphysis* of long bones (especially femur), pelvic flat bones. - Most common in Caucasians; Generally boys < 15 years old. - Anaplastic small blue cells of neuroectodermal origin (resemble lymphocytes) *aka* - sheets of uniform, small, round, cells with clear, scant cytoplasm separated by fibrous septae and patches of necrosis/hemorrhage. - "Onion skin" periosteal reaction in bone. - Aggressive with early metastases, but responsive to chemotherapy.
In abruptio placenta, blood loss is from what rupture of which vessels?
*Maternal* vessels in *decidua basalis* - blood separates decidua from uterus - loss of gas and nutrient exchange - life threatening to mother and fetus
What is used to prevent trypsin from activating before it enters the duodenum (preventing pancreatitis)?
*Serine peptidase inhibitor Kazal-type 1 (SPINK1)* - secreted by pancreatic acinar cells and functions as a trypsin inhibitor - It impedes the activity of trypsinogen molecules that become prematurely activated within the pancreas. *Trypsin* - In addition to functioning as its own activator, trypsin can serve as its own inhibitor by cleaving active trypsin molecules at a second site, rendering them inactive. - *Hereditary pancreatitis* is a rare disorder that results from mutations involving the trypsinogen or SPINK1 gene. The most common mutation leads to the production of abnormal trypsin that is not susceptible to inactivating cleavage by trypsin. Because a small amount of trypsinogen normally activates prematurely within the pancreatic acini and ducts, these protective mechanisms are critical for preventing recurrent attacks of acute pancreatitis.
*High-altitude pulmonary edema* presents with dyspnea and cough within several days of arrival at high altitude. It is driven by reduced ambient oxygen, which leads to hypoxic pulmonary vasoconstriction and pulmonary arterial hypertension. Individuals with unevenly distributed pulmonary vasoconstriction can develop areas of high capillary perfusion pressure that ______ , leading to *patchy, bilateral pulmonary edema*.
*disrupts the alveolar-capillary membrane*
Activated macrophages in sarcoidosis and other granulomatous diseases express _______ , leading to excess production of _______ and hypercalcemia
- 1-α-hydroxylase - 1,25-dihydroxyvitamin D
Thiopurine methyltransferase is responsible for the metabolism of thiopurine compounds such as the immunosuppressive drug _______ . Enzyme deficiency leads to increased drug toxicity.
- 6-mercaptopurine
During the development of atherosclerotic plaque (atheroma), ________ release growth factors (eg, platelet-derived growth factor) that stimulate recruitment of smooth muscle cells from the arterial wall media and their subsequent proliferation in the intima.
- Activated macrophages - Platelets - Endothelial cells
Dx Cushing Syndrome: Low ACTH levels
- Adrenal Adenoma - Adrenal Malignancy - Exogenous glucocorticoid intake Excess ACTH secretion causes identifiable clinical findings: - Hyperpigmentation: Both ACTH and alpha-melanocyte-stimulating hormone (MSH) are derived from pro-opiomelanocortin, leading to cosecretion of alpha-MSH. ACTH also directly stimulates the MC2R receptor on melanocytes. - Androgenization: ACTH stimulates production of adrenal androgens (eg, ↑DHEAS [dehydroepiandrosterone sulfate], androstenedione). This leads to hirsutism, menstrual abnormalities, and oily skin.
_________ is an adverse effect of anti-hyperthyroid meds that initially manifests as fever, sore throat, and oral ulcerations
- Agranulocytosis (drug induced granulocyte destruction --> neutropenia) - requires immediate discontinuation of drug!
Derivatives from Surface ectoderm:
- Anterior pituitary (Rathke pouch) - Lens & cornea - Inner ear sensory organs, olfactory epithelium - Nasal & oral epithelial linings, salivary glands - Epidermis, sweat & mammary glands
_________ causes a linear deposition of IgG and C3 on the GBM and EM demonstrates breakage of the GBM, but immune complex deposits are absent.
- Antiglomerular basement membrane disease - it typically results in a crescentic glomerulonephritis (eg, nephritic syndrome; hematuria, red blood cell casts) visible on LM.
What murmurs increase in intensity with handgrip?
- Aortic Regurg - Mitral Regurg - VSD [HCM and AS decrease] [ increases LV and aortic pressure and afterload]
Other complications from psoriasis:
- Arthritis* - Nail changes (pitting, discoloration) - Uveitis (kind of like in rosacea)
The vegetative form of __________ contains a polypeptide capsule composed of D-glutamic acid, which is antiphagocytic.
- Bacillus anthracis - B anthracis rods also produce a potent exotoxin complex composed of edema factor, lethal factor, and protective antigen, which enter host cells and cause cell death.
_______ promotes gallstone formation by providing a favorable environment for crystal nucleation and aggregation.
- Biliary stasis - Stasis can occur due to gallbladder denervation (eg, transection of the nerves that control gallbladder contraction) or decreased stimulation by enterocytes during prolonged fasting (cholecystokinin is released in response to food). - However, stasis usually promotes the formation of yellow cholesterol stones, and this patient did not have prolonged fasting or surgery prior to developing her symptoms
_______ form due to supersaturation of the bile with bilirubin, which precipitates with calcium to form ________.
- Black gallstones - calcium bilirubinate stones - This typically occurs in the setting of chronic hemolysis (eg, sickle cell disease) or altered enterohepatic circulation of bilirubin (eg, Crohn disease, ileal resection). - Increased cholesterol synthesis results in the formation of yellow cholesterol gallstones. This typically occurs in the setting of obesity, diabetes mellitus, or certain medications (eg, estrogen-containing oral contraceptives).
Derivatives of neural tube (ectoderm)
- Brain & spinal cord - Posterior pituitary - Pineal gland - Retina
What type of esophagitis *intranuclear & cytoplasmic inclusions*? What is the treatment?
- CMV - Ganicyclovir - Contrast: HSV = eosinophilic intranuclear inclusions in multinuclear squamous cells at ulcer margins
_______ infection causes exotoxin-mediated damage to the large intestine mucosa, leading to the development of yellow-white pseudomembranes.
- Clostridioides difficile - Cases are most common after recent antibiotic therapy and usually present with watery diarrhea, fever, and abdominal pain. C difficile is a spore-forming, gram-positive bacterium.
Holoprosencephaly
- Failure of the embryonic forebrain (prosencephalon) to separate into 2 cerebral hemispheres; usually occurs during weeks 5-6. - May be related to mutations in *sonic hedgehog* signaling pathway. - Associated with other midline defects including cleft lip/palate (moderate form) and cyclopia (severe form). - Increased risk for pituitary dysfunction (eg, diabetes insipidus). - Can be seen with *Patau syndrome (trisomy 13)*. MRI reveals monoventricle and fusion of basal ganglia
Femoral hernia
- Females - Protrudes below inguinal ligament, through femoral canal
In RPGN, the crescents consist of what?
- Fibrin - Parietal cells - Monocytes, Macrophages, - Plasma Proteins (C3b)
This patient with ________ most likely developed gallstones due to inflammation of the terminal ileum causing decreased bile acid reabsorption.
- Crohn disease - Bile acids are produced in the liver and excreted with bile into the duodenum. There, they *emulsify fat droplets* to form water-soluble micelles that allow pancreatic lipase to efficiently hydrolyze triglycerides into fatty acids and monoglycerides. - In the jejunum, these micelles come in close contact with the gut epithelium, which facilitates the passive absorption of fatty acids, monoglycerides, and cholesterol across the brush border into enterocytes. - However, bile acids are ionized molecules that cannot passively cross the intestinal wall. The bile acids eventually reach the terminal ileum, where specialized transport proteins allow them to be reabsorbed. - The terminal ileum is a typical location of activity in Crohn disease. When the mucosa of the terminal ileum is inflamed, bile acids are lost in the feces. As a result, a lesser amount of bile acid is present in the bile, so the ratio of cholesterol/bile acids increases. Supersaturation of the bile with cholesterol then leads to formation of gallstones.
Rhadbomyolysis is a common AE from:
- Crush injuries - Seizures - Integrase inhibitors (-tegravir) - Statins - Daptomycin - Amphetimines, Heroin - Prolonged muscle use (marathons) Look for positive blood with absent RBCs in urine
Vibrio general characteristics
- Curved Gram negative rod - *Oxidase positive* - Does NOT ferment lactose - highly motile - grows better in alkaline environment (look for PPIs, antacids)
Male sex hormone levels change with age:
- Decrease in total testosterone and free testosterone - Rise in circulating LH - Rise in sex-hormone binding globulin
______ is characterized by *proximal* muscle weakness, with additional inflammatory features affecting the skin (eg, heliotrope rash, Gottron papules). Involvement of striated muscle in the oropharynx and heart can lead to dysphagia, pulmonary aspiration, and myocarditis
- Dermatomyositis - painless proximal muscle weakness; in association with the heliotrope rash on her eyelids, this presentation is consistent with dermatomyositis, an inflammatory myopathy that primarily affects striated muscle and skin - dermatomyositis affects only the striated muscle in the oropharynx and upper esophagus (eg, choking, aspiration), whereas scleroderma can affect the lower esophagus - treatment: glucocorticoids
_________ is a part of the normal gastrointestinal flora, and special adhesive proteins ( ________ ) allow some strains to colonize and ascend the urinary tract.
- E coli - fimbriae - This can result in UTI, pyelonephritis, or bacteremia and sepsis following access to the bloodstream. UTIs are the most common cause of E coli bacteremia.
Breast cancer risk factors
- Early menarche - late menopause - Nulliparity - BRCA mutations
Chiari 1 Malformation
- Ectopia of cerebellar tonsils inferior to foramen magnum (1 structure). - Congenital, usually asymptomatic in childhood - Manifests in adulthood with headaches and cerebellar symptoms. - Associated with spinal cavitations (eg, syringomyelia).
Amyloid Beta-2 microglobulin is associated with which disease condtions?
- End-stage Renal Disease (ESRD) - Dialysis > 5 years - Disease most often involves osteoarticular structures as connective tissue components (eg, glycosaminoglycans, type-1 collagen) stabilize beta2-m amyloid fibrils and inhibit their depolymerization. - Typical manifestations include: - Scapulohumeral periarthritis (pain/hypertrophy from rotator cuff infiltration) - Carpal tunnel syndrome (median neuropathy from carpal tunnel deposition) - Flexor tenosynovitis (contractures from involvement of flexor tendons) - Bone cysts (possible pathologic fractures)
Thumbprint/Thumbs sign: pathology and causative organism
- Epiglottitis - H influenza (type B, Hib) [gram neg coccobacilli] - tripod position
_______ is a platelet glycoprotein IIb/IIIa inhibitor that inhibits the final common pathway of platelet aggregation.
- Eptifibatide - Tirofiban - Abciximab - Given IV only;
_________ is a delayed-type hypersensitivity reaction that presents with tender, *painful* inflammatory nodules in the subcutaneous fat, primarily on the shins.
- Erythema nodosum - The characteristic histopathologic finding is septal panniculitis in the subcutaneous tissues, with a variable (lymphocytes, neutrophils, macrophages) infiltrate. - Can be associated with sarcoidosis, coccidioidomycosis, histoplasmosis, TB, streptococcal infections , leprosy, inflammatory bowel disease.
Urgency incontinence
- Etiology: Detrusor hyperactivity - Symptoms: Sudden, overwhelming urge to urinate + leak - Associations: UTI - Treatment: Kegel exercises, bladder training (timed voiding, distraction or relaxation techniques), antimuscarinics (eg, oxybutynin for overactive bladder), mirabegron
How does aging effect Total Lung capacity, Residual volume, and Forced vital capacity? Physeologic dead space? PaO2? A/a gradient? Total Respiratory system compliance?
- FVC: Decreased - Residual Volume: Increased - Total Lung Capacity: Unchanged - A/a: Increased - PaO2: Decreased - Physeological Dead space: Increased - Total Respiratory System compliance: Decreased - Aging is associated with steady decreases in chest wall compliance but increases in lung compliance due to a loss of elastic recoil. This results in a marked increase in residual volume, a decrease in forced vital capacity, and relatively unchanged total lung capacity - Aging is associated with a number of changes in pulmonary function. Patients age >35 experience steady decreases in chest wall compliance as a result of stiffening from rib calcification and from increased thoracic curvature due to osteoporosis and osteoarthritis. In contrast, lung compliance increases with age due to a loss of elastic recoil, particularly in the alveolar ducts. The dilation of alveolar ducts is homogenous, as opposed to the emphysema associated with chronic obstructive pulmonary disease, and is not associated with destruction of the alveolar walls. - Normal aging is characterized by decreased respiratory system compliance (increased lung compliance outweighed by higher chest wall stiffness) and increased dead space (loss of alveolar surface area). For this reason, elderly persons are less equipped to tolerate illnesses that impair respiratory compliance and/or gas exchange (eg, pneumonia, pulmonary edema).
_______ inhibits the synthesis of both DNA (replication) and RNA (protein synthesis) in fungal cells.
- Flucytosine - It is mainly used as a synergistic agent with amphotericin B, particularly in the treatment of cryptococcal meningitis.
Derivatives of Endoderm
- Gastrointestinal tract, liver, pancreas - Lungs - Thymus, parathyroids, thyroid follicular cells - Middle ear epithelium - Bladder & urethra - Parafollicular (C) cells*
What is used to treat Beta blocker overdose? What is its MOA?
- Glucagon - Activates adenyl cyclase --> increase cAMP --> Ca release from intracellular stores --> increased SA node firing
Is E coli urease or nitrite positive? Does it ferment lactose
- Gram neg rod - Ferments lactose - Forms pink colonies on MacKonkey - Urease negative (non-alkaline urine) - Nitrite positive on dipstick, greenish metallic sheen on culture (EMB agar) - Does NOT produce staghorns. If staghorn, think either proteus or s. saprophyticus. S. saprophyticus is young, sexually active women
Is Proteus *urease* positive or negative?
- Gram negative, urease-positive, non-lactose fermenting - Urease positive (alkaline urine pH) - Struvite crystals (coffin lid crystals) --> Radioopaque - Staghorn calculi
________ enters fungal cells, binds microtubules, and inhibits mitosis.
- Griseofulvin - This antifungal drug is effective only against dermatophyte fungi as it accumulates in keratin-containing tissues.
What type of esophagitis describes *eosinophilic intranuclear inclusions* in multinuclear squamous cells at ulcer margins? What is the treatment?
- HSV (eosinophilic inclusions = Cowdry type A) [punched out ulcers/distinct borders] - Acyclovir - Contrast: CMV = intranuclear & cytoplasmic inclusions
_______ is the single most important measure to reduce the risk of transmission of hospital-acquired infections.
- Hand hygiene - Contact precautions are indicated when caring for patients with specific multidrug-resistant bacteria (ex: MRSA) - Isolation is for airborne illnesses The most important steps for prevention of central venous catheter infections are as follows: - Proper hand hygiene - Full barrier precautions during insertion - Chlorhexidine skin disinfection - Avoidance of the femoral insertion site - Removal of the catheter when it is no longer needed
Causes of "Target cells"
- Hemoglobin C disease - Asplenia - Liver disease - Thalesemia Side Note: - Macrophages in the red pulp of the spleen remove excess membrane from red cells, a process called "splenic conditioning." Patients who undergo splenectomy are unable to prune erythrocytes and generally develop target cells a few weeks following the procedure. However, over time, macrophages in nonsplenic tissue (eg, liver) take up the task of pruning erythrocytes, which typically eliminates (or diminishes) the presence of target cells in the circulation.
Liver cancer risk factors
- Hep B and C - Liver cirrhosis (any cause) - Hemochromatosis - Aflatoxin
Tumor Marker: Alpha-fetoprotein Associations: ???
- Hepatocellular carcinoma - germ cell tumor - AFP is a glycoprotein produced by the fetal liver and yolk sac during gestation. - Although levels of AFP are often mildly or moderately elevated in patients with chronic liver disease, dramatic elevations or sudden rises in AFP should prompt an investigation for HCC. - AFP levels do not correlate with the size or stage of the tumor and are not elevated in all cases of HCC.
Colorectal cancer risk factors
- Hereditary CRC syndromes - Inflammatory bowel disease - Obesity - Charred or fried foods
Causes of Fanconi syndrome
- Hereditary defects (eg, Wilson disease, tyrosinemia, glycogen storage disease), - ischemia, - multiple myeloma, - nephrotoxins/drugs (eg, ifosfamide, cisplatin), - lead poisoning
Chiari 2 malformation
- Herniation of cerebellar vermis and tonsils (2 structures) through foramen magnum with aqueductal stenosis --> noncommunicating hydrocephalus. - Usually associated with lumbosacral myelomeningocele (may present as paralysis/sensory loss at and below the level of the lesion). - More severe than Chiari I, usually presents early in life.
_________ , which causes __________ , most commonly presents with fever for 3-5 days, followed by a diffuse/trunal, maculopapular rash in young children.
- Human herpesvirus 6 (HHV-6) - roseola infantum - Vesicles would not be seen, and infection in immunocompetent adults is rare. - Patients with rubella often have Forchheimer spots on the soft palate, and measles is characterized by pathognomonic Koplik spots on buccal mucosa.
Migratory thrombophlebitis should raise suspicion for cancer.
- Hypercoagulability is a very common paraneoplastic syndrome seen most frequently in visceral adenocarcinomas of the pancreas, colon, and lung [patient may describe vague abdominal pain]. - Hypercoagulability develops because adenocarcinomas produce a thromboplastin-like substance capable of causing chronic intravascular coagulations that can disseminate and tend to migrate. - Migratory superficial thrombophlebitis, known as *Trousseau syndrome*
Effect of Hypothyroidism on LDL
- Hypothyroidism causes *decreased expression of LDL receptors* in the liver, leading to decreased clearance of LDL and increased blood LDL levels. - It also causes hypertriglyceridemia due to decreased expression of lipoprotein lipase. - The adverse effects of hypothyroidism on lipid levels can increase the risk of coronary atherosclerosis.
How does a prolactinoma increase the risk for fractures in a patient?
- In patients with prolactinoma, high levels of circulating prolactin suppress GnRH secretion from the hypothalamus, leading to reduced secretion of LH and subsequent hypogonadism, anovulation, and amenorrhea. - The resulting estrogen deficiency can cause osteoporosis with an increased risk for fragility fractures, and lead to vaginal dryness and atrophy -- Men with prolactinomas may develop symptoms due to hypogonadism (eg, infertility, decreased libido), but galactorrhea is rare in both men and postmenopausal women as milk production requires estrogen/progesterone priming of the breast tissue. -- Men with prolactinomas are more likely to present at an advanced stage with mass-effect symptoms (eg, headache, visual field defects) due to compression of surrounding structures.
Is Toxic Megacolon associated with Ulcerative Colitis or Crohn's?
- Ulcerative colitis - Toxic megacolon can also be associated with Clostridium difficile infection and other forms of infectious colitis. - Patients typically present with abdominal pain/distension, bloody diarrhea, fever, and signs of shock. - Plain abdominal x-ray is the preferred diagnostic imaging study. - Barium contrast studies and colonoscopy are contraindicated due to the risk of perforation.
Cholesterol stone formation occurs due to the following:
- Increased cholesterol synthesis: Hypercholesterolemia, caused by diet, genetics, diabetes mellitus, medications (eg, oral contraceptives), or obesity (increased HMG-CoA reductase activity), results in hypersecretion of cholesterol into the bile. - Gallbladder hypomotility: Pregnancy, medications (eg, somatostatin), prolonged fasting, parenteral nutrition, and spinal cord injury lead to gallbladder stasis, which promotes excessive water resorption from bile and concentration of cholesterol. - Decreased bile acid synthesis (or recirculation): *Fibrates (eg, fenofibrate)* inhibit bile acid synthesis, increasing cholesterol concentration within the bile. Decreased bile acid resorption at the ileum (eg, due to Crohn disease) also promotes cholesterol concentration. - Increased calcium or mucin concentration: Rapid weight loss (eg, gastric bypass) promotes increased calcium and mucin concentrations in the bile, which trap cholesterol crystals and promote stone formation.
Prostate cancer risk factors
- Increasing age - African American
AE of Amiodarone
- Interstitial pulmonary fibrosis - Hypo/Hyperthyroidism - Blue-Gray discoloration of skin (gray baby syndrome = cloramphenicol) - Cardiac arrhythmias - Elevated Liver enzymes
What activating mutations are involved in lung adenocarcinoma?
- KRAS - EGFR - ALK - *Extra:* may be associated with clubbing or hypertrophic osteoarthropathy.
How does hypovolemia affect RPF, GFR, FF?
- Large decrease in RPF - Small decrease in GFR (due to compensation) - Increase in FF (GFR/RPF) ex: diarrhea and/or vomiting --> hypovolemia
__(This enzyme)___ degrades membrane phospholipids , leading to cell membrane destruction and cell death.
- Lecithinase (also known as phospholipase C, or Clostridium perfringens alpha-toxin) is the exotoxin released by C perfringens. - This enzyme degrades membrane phospholipids (including lecithin), leading to cell membrane destruction and cell death. - C perfringens causes gas gangrene.
_______ are obligate intracellular protozoa that mature in macrophages and can be identified on biopsy by the presence of rod-shaped kinetoplasts.
- Leishmania species - They are transmitted to humans by infected sand flies and cause the clinical syndrome of cutaneous leishmaniasis, characterized by a chronic, pinkish papule that evolves into a nodule or plaque.
_________ Leprosy, the most severe form, occurs in patients with a weak ______ immune response. Macrophage signaling to kill M leprae is limited, leading to mycobacterial dissemination. Manifestations include diffuse skin thickening, plaque-like hypopigmentation (often with hair loss), leonine facies, paresis, regional anesthesia, testicular destruction, and blindness.
- Lepromatous leprosy (LL) - Cell mediated [Therefore have a Humoral mediated response instead (Th2-mediated)]
With maternal blood types A or B, hemolytic disease of the fetus and newborn very rarely occurs because maternal antibodies (anti-A or anti-B) are of the Ig___ type and cannot cross the placenta. In contrast, mothers with blood type O also produce Ig___ antibodies (anti-A and anti-B), which can cross the placenta and cause fetal hemolysis.
- M - G - Hemolytic disease of the fetus and newborn (HDFN) is caused by maternal anti-fetal erythrocyte IgG antibodies, which can cross the placenta and produce a type II (antibody-mediated) hypersensitivity response. With maternal blood types A or B, hemolysis (eg, erythrocyte destruction) does not occur because the maternal antibodies (anti-A or anti-B) are of the IgM type, which cannot cross the placenta. However, mothers with blood type O also produce IgG antibodies which can cause hemolysis in the fetus. - The association of a fetus with blood type A or B and a mother with blood type O occurs in approximately 15% of pregnancies; however, HDFN occurs in only 3% of these pregnancies due to variations in fetal ABO antigen expression. Unlike Rh disease, HDFN can occur with the first pregnancy because anti-A and anti-B antibodies are formed early in life from exposure to A- or B-like antigens present in foods, bacteria, and viruses.
Lynch syndrome mutation
- MSH 2/6 - MLH1 - 50-80% colon cancer risk - Also associated with endometrial and ovarian neoplasms
Chondrosarcoma
- Male - Age > 40 - Pelvis, ribs, shoulders - Hematogenous spread to lungs in high grade lesions 1. Conventional (most common) 2. Clear cell (younger patients) - Sheets of large, malignant chondrocytes with abundant clear cytoplasm - Numerous osteoclast like giant cells Intralesional bone formation Seen in younger patients (teens and twenties) 3. De-Differentiated - Low grade chondrosarcoma - Has a second high grade sarcoma component that does not produce cartilage Hence, "de"-differentiated 4. Mesenchymal (younger patients) - Islands of hyalin cartilage surrounded by small, round blue cells - Poor prognosis - Seen in younger patients (teens and twenties)
_______ intracytoplasmic eosinophilic inclusions of damaged keratin filaments and are seen in ____(condition)_____
- Mallory bodies - alcoholic hepatitis
How to dx a congenital (ex: torch) infection in a neonate:
- Maternal IgM does not cross the placenta, so detection of organism-specific IgM in a symptomatic neonate is diagnostic. - At birth, virtually all infant IgG is maternally derived IgG that crossed the placenta, and elevated maternal IgG would be expected in this mother with infectious symptoms 6-7 months prior to delivery. Therefore, organism-specific newborn IgG (eg, Toxoplasma IgG) will also be elevated in the setting of a past maternal infection. - In other words: High IgG in mom, child has high IgM and IgG [high IgM in child is dx because they won't get that from mom]
Complications of Abruptio Placenta
- Maternal shock - Fetal distress/demise - *DIC* ********* - *Cortical necrosis*--> -- ischemic necrosis of renal cortex -- can cause permanent renal failure -- Presentation: --- Acute renal failure --- Anuria --- Hematuria (may be gross) --- Flank pain
What diabetic drug is a biguanide and what is its MOA?
- Metformin [increases insulin sensitivity like "glit" drugs] MOA: - Inhibit mGPD --> *inhibition of hepatic gluconeogenesis* and the action of glucagon. - *Increase glycolysis, peripheral glucose uptake (increase insulin sensitivity)*. - ↓ Hepatic glucose production ↓ Intestinal glucose absorption ↑ Peripheral glucose uptake/utilization ↓ Lipogenesis [does not increase insulin production, increases sensitivity] AE: - GI upset, lactic acidosis (use with caution in renal insufficiency), vitamin B12 deficiency. - Weight loss (often desired).
Toxic Shock syndrome pathogenesis
- Most cases are linked to prolonged tampon use or nasal wound packing, which provides a medium for localized Staphylococcus aureus proliferation and the elaboration of pyrogenic toxin superantigens (eg, toxic shock syndrome toxin-1 [TSST-1]) into the bloodstream. - These exotoxins are called superantigens because they bind to the invariant region of the MHC-II complex of antigen-presenting cells without first being internalized and processed (MHC-II antigens are normally processed by the phagolysosome). - --> The superantigen/MHC-II complex subsequently interacts with the variable part of the T-cell receptor beta chain --> nonspecific stimulation of a large percentage of T cells --> the massive release of inflammatory cytokines (eg, IL-1, IL-2, TNF-alpha & beta, interferon-gamma). - --> Cytokine release mediates the major manifestations of TSS including fever, increased capillary permeability, and hypotension.
Suicide facts
- Most common method in US is firearms; access to guns increases risk of suicide completion. - Women try more often; men complete more often. - Other risk factors include recent psychiatric hospitalization and family history of completed suicide. - Risk Factors: Sex (male) Age (young adult or elderly) Depression Previous attempt (highest risk factor) Ethanol or drug use Rational thinking loss (psychosis) Sickness (medical illness) Organized plan No spouse or other social support Stated future intent
atrial myxoma
- Most common primary cardiac tumor in adults - left sided (usually *left atrium*) [may mimic mitral valve stenosis] - can present with systemic embolization (ex: *stroke*, multiple syncope episodes) - IL-6 production by tumor --> constitutional symptoms (eg, fever, weight loss). - because of high vascularity, often see areas of hemorrhage --> brown, hemosiderin-laden macrophages - May auscultate early diastolic "tumor plop" sound. - Histology: gelatinous material, myxoma cells immersed in glycosaminoglycans. [morphous extracellular matrix with scattered stellate or globular myxoma cells within abundant mucopolysaccharide (myxoid) ground substance containing chondroitin sulfate and hyaluronic acid.]
Functions of CN 7
- Motor output to the muscles controlling movement of the face (including eye closure) [not the muscles of mastication tho (CN5)] - Somatic sensation afferents from portions of the pinna and external auditory canal - Special sensation afferents for taste from the anterior two-thirds of the tongue - Parasympathetic innervation of the submandibular and lacrimal glands - Motor innervation of the stapedius muscle, which causes sound dampening
Amyloid Light Chain (AL) is associated with which disease conditions
- Multiple Myeloma - Waldenström macroglobulinemia
Derivatives of Mesoderm
- Muscles (skeletal, cardiac & smooth) - Connective tissue, bone & cartilage - Serosal linings (eg, peritoneum) - Cardiovascular & lymphatic system - Spleen & hemopoietic cells - Kidney & ureters, internal genitalia - Adrenal cortex
Derivatives of Neural crest (ectoderm)
- Neural ganglia, - Adrenal medulla - Schwann cells; pia & arachnoid mater - Aorticopulmonary septum & endocardial cushions - Branchial arches (bones & cartilage) - Skull bones - Melanocytes
AE of ganciclovir
- Neutropenia - Anemia - Thrombocytopenia - First-line therapy for CMV colitis and retinitis is ganciclovir. - Inhibits viral synthesis by blocking CMV DNA polymerase. However, ganciclovir also blocks host DNA polymerase to a lesser degree --> AE listed above
Distinguishing non-cardiogenic pulmonary edema vs cardiogenic pulmonary edema
- Noncardiogenic pulmonary edema (eg, ARDS, high-altitude pulmonary edema) can be distinguished from cardiogenic pulmonary edema (eg, decompensated left ventricular failure, volume overload) by a normal pulmonary capillary wedge pressure (6-12 mm Hg). - Other distinguishing features include the clinical history (pneumonia/sepsis or pancreatitis suggests ARDS) and physical exam (peripheral edema and jugular venous distension suggest a cardiogenic source).
Immune Thrombocytopenia - Platelet count: - Bleeding time:
- PC: decreased - BT: increased Destruction of platelets in spleen. Anti-GpIIb/IIIa antibodies --> splenic macrophages phagocytose platelets. May be idiopathic or 2° to autoimmune disorders (eg, SLE), viral illness (eg, HIV, HCV), malignancy (eg, CLL), or drug reactions. Labs: increased megakaryocytes on bone marrow biopsy, decreased platelet count. Treatment: steroids, IVIG, rituximab, TPO receptor agonists (eg, eltrombopag, romiplostim), or splenectomy for refractory ITP.
Glanzmann Thrombasthenia - Platelet count: - Bleeding time:
- PC: normal - BT: increased
What cancers have perineural spread (spread via nerves/nerve sheaths)?
- Pancreatic ductal adenocarcinoma - Prostate cancer
Von Hippel-Lindau (VHL) disease is an autosomal dominant condition caused by a mutation in a tumor suppressor gene, which is associated with the development of
- Pheochromocytomas - Retinal and cerebellar hemangioblastomas - Renal cell carcinomas. - Because of the potential for serious complications from these tumors, patients with VHL should receive annual surveillance, including plasma metanephrines, abdominal imaging, ophthalmologic examination, and MRI of the brain and spine.
Bernard-Soulier syndrome - Platelet count: - Bleeding time:
- Platelet count: normal/decreased - BT: Increased
What is the function of M protein in Strep Pyogenes?
- Prevents phagocytosis; inactivates compliment (by binding factor H); aids in epithelial cell attachment - Involved in pathogenesis of necrotizing fascitis - shares structural homology with tropomyosin and myosin - can cross react with myosin epitopes in heart --> rheumatic carditis
______typically presents with bloody diarrhea associated with abdominal pain and tenesmus.
- Ulcerative colitis - Can lead to toxic megacolon - Fistula formation does not usually occur as inflammation is confined to the mucosa and submucosa
The only glycosylated HIV polyprotein is ______ , the product of the _____ gene
- gp160 - env - gp160 is extensively glycosylated in the rough endoplasmic reticulum and Golgi apparatus. It is then cleaved into the envelope proteins gp120, which mediates viral attachment, and gp41, which mediates viral fusion with the host cell.
Non-cardioselective beta blockers
- Propanolol - Pindolol - Sotalol - Labetolol - Timolol - Carvedilol - The alpha-1 receptor blockade outweighs beta-2 receptor blockade in vascular smooth muscle to cause peripheral vasodilation of both venules and arterioles. Venular vasodilation decreases venous return and arteriolar vasodilation decreases systemic vascular resistance (SVR); because the vasodilation is relatively balanced, blood pressure is reduced with stroke volume unchanged. - Normally, reduced blood pressure stimulates a baroreceptor reflex-mediated increase in heart rate, but the strong beta-1 receptor blockade of labetalol overrides this response, causing overall decreased heart rate. - Blocks both beta 1 + beta 2 receptors (in lungs) - Don't give to person w/ resp illness including asthma, emphysema, chronic bronchitis - If block beta 2 receptors → causes bronchoconstriction, increased airway resistance → creates bigger problem than already have if resp problem
Direct Inguinal hernia
- Protrudes through Inguinal (Hesselbach) triangle - Bulges directly through the parietal peritonium medial to the inferior epigastric vessels - Goes through the external (superficial) inguinal ring only - Covered by external spermatic fascia - Due to weakened abdominal wall musculature - Older males due to weakness of transversalis fascia
Bats can transmit __________ to humans via a bite wound.
- Rabies - can also be transmitted by racoons - Manifestations typically begin with flulike symptoms and progress to fever, hydrophobia, pharyngeal spasms, coma, and death. - Rabies is a cylindrical, enveloped RNA virus; it is not a motile, corkscrew-shaped organism.
Eighty percent of acute pancreatitis cases are caused by gallstones and chronic alcoholism. Less common causes of acute pancreatitis:
- Recent endoscopic retrograde cholangiopancreatography (ERCP) procedure - Drugs (eg, azathioprine, sulfasalazine, furosemide, valproic acid) - Infections (eg, mumps, Coxsackie virus, Mycoplasma pneumoniae) - Hypertriglyceridemia - Structural abnormalities of the pancreatic duct (strictures, cancer, pancreas divisum) or of the ampullary region (choledochal cyst, stenosis of sphincter of Oddi) - Surgery (particularly of the stomach and biliary tract and after cardiac surgery) - Hypercalcemia
What stains with Giemsa?
- Ricketsia (RMSF?) - Chlamydia - Trypanosomes (Chagas, etc.) - Plasmodium - Borelia - H pylori
The major environmental reservoir for Yersinia is
- Rodents, and transmission usually occurs via rodent flea bite. - Associated with southwest US (new mexico) - Bubonic plague is a zoonotic infection that causes febrile illness with regional inflammatory lymphadenopathy (buboes). The underlying pathogen is Yersinia pestis, a gram-negative coccobacillus that exhibits bipolar staining (resembling a closed safety pin on Giemsa or Wright).
PJ syndrome mutation
- STK11
What cancers have hematogenous spread?
- Sarcomma - Renal cell carcinoma - Hepatocellular carcinoma
______ is most common in patients with a history of sandblasting or mining.
- Silicosis - Numerous upper lobe nodular densities and eggshell calcifications of the hilar nodes are seen; pleural plaques are unexpected.
Dimorphic fungi grow as molds at 25-30ºC and as yeast at body temperature (35-37ºC). Medically important dimorphic fungi include _____ species.
- Sporothrix, - Coccidioides, - Histoplasma, - Blastomyces - Paracoccidioides
What conditions have caseating granulomas?
- TB - Cat scratch disease - leprosy - syphillis
______ is a NRTI that is generally well tolerated but may occasionally cause damage to the proximal tubule of the kidney, leading to acute kidney injury and/or proximal tubule impairment (eg, phosphoruria, glucosuria, proteinuria, water retention)
- Tenofovir - Biopsy typically reveals a normal glomerulus and renal interstitium but damage to the proximal tubule and evidence of giant mitochondria (eg, large eosinophilic inclusions)
How is airway resistance related to each level of the airway?
- The airway resistance at each level of the lower respiratory tract is inversely related to the total cross-sectional area of all the airways at that level. - Airway resistance is high in the trachea and reaches a *peak in the medium-sized bronchi, where total cross-sectional area is at a minimum*. - Airway resistance then progressively decreases as total cross-sectional area increases through the smaller bronchioles, terminal bronchioles, and alveoli. (By the time the alveoli are reached, the total cross-sectional area is massive (~5 × 105 cm2) and airway resistance is essentially zero.)
It invades the skeletal muscle and causes severe muscle pain, swelling, and tenderness. Periorbital edema and eosinophilia are often important diagnostic clues
- The roundworm Trichinella - can be transmitted via undercooked pork
Indirect Inguinal hernia
- Through internal (deep) inguinal canal/ring lateral to inferior epigastric vessels --> external (superficial) ring --> into the groin - Caused by failure of process vaginalis to close - Can form hydrocele - Infants are common - Males - Covered by all 3 layers of spermatic fascia (follows pathway of testicular descent)
First line therapy for scabies
- Topical Permethrin, which blocks mite neurotransmission by impairing voltage-gated sodium channels. - Oral ivermectin, an antiparasitic agent that binds chloride ion channels in invertebrate nerve and muscle cells, is an alternate medication for classic scabies that is used in combination with permethrin for crusted scabies.
_______ is transmitted by ingesting contaminated swine
- Trichinella, a roundworm - often associated with transient gastrointestinal symptoms followed by skeletal muscle pain, tenderness, swelling, and weakness.
________ leprosy is the least severe form and is often self-limited. _______ infection is limited by an intact __________ immune response. Mild skin plaques develop and are associated with hypopigmentation, hair follicle loss, and focally decreased sensation.
- Tuberculoid Leprosy - Mycobacterial - Cell Mediated (Th1)
________ contain a capsular antigen (Vi) that inhibits neutrophil phagocytosis, neutrophil recruitment, and macrophage-mediated destruction.
- Typhoid strains of Salmonella - Therefore, typhoid strains are able to undergo extensive replication within the intracellular space of macrophages with subsequent spread through the lymphatic and reticuloendothelial system, leading to a widespread systemic disease (typhoid fever).
Does insulin increase the secretion of LPL or Hormone sensitive Lipase?
- Upregulates lipoprotein lipase (an enzyme that hydrolyzes triglycerides in chylomicrons and VLDL) in adipose tissue capillaries; the liberated fatty acids are taken up by adipose cells, lowering serum triglyceride levels. - Reduces the activity of hormone-sensitive lipase in adipose tissue, suppressing the release of fatty acids. - Side Note: Pyruvate carboxylase catalyzes the conversion of pyruvate to oxaloacetate, which can be used to drive lipid synthesis (citrate-malate shuttle) or diverted to gluconeogenesis. Insulin downregulates (not upregulates) its activity in the liver, leading to reduced gluconeogenesis and hepatic fatty acid production.
_______ is a curved, gram-negative, free-living bacterium that grows in marine environments.
- Vibrio vulnificus - Transmission primarily occurs due to the consumption of raw seafood (eg, oysters) or wound contamination. - Manifestations are often mild [cellulitis], but individuals with liver disease or iron overload are at very high risk of severe, fulminant infection (eg, sepsis, necrotizing fascitis).
HIV-2, which is endemic to _______ .
- West Africa - HIV-2 infection is associated with lower viral loads, less risk of transmission, and a slower progression to AIDS. - The diagnosis is often suspected when HIV tests are incongruent (positive screening serology but indeterminate Western blot and negative plasma HIV-1 RNA). - Confirmation can be made using HIV-1/HIV-2 immunodifferentiation assay. - The window period occurs during early HIV infection when serologic testing and antigen testing for HIV are not yet positive
Is S. saphrophiticus urease or nitrite positive?
- Young, sexually active women --> "Honeymoon cystitis" --> presents within 24 hours of sexual activity - Urease positive [Splits urea into CO2 and NH3 --> alkaline urine pH, struvite crystals (coffin lid) --> Struvite crystals are radioopaque] - Nitrite negative
___________ is characterized by distal duodenal ulcer and high-normal gastrin levels that rise in response to secretin administration
- Zollinger-Ellison syndrome - In contrast, secretin inhibits release of gastrin from normal gastric G cells. - Secretin is a hormone released from the duodenum in response to acid and fat in the small intestine. The hormone increases pancreatic bicarbonate secretion and inhibits the release of gastrin from normal gastric G cells. - However, secretin paradoxically stimulates gastrin release from gastrinomas due to abnormal adenylate cyclase activation. As such, secretin administration can be used to differentiate ZES from other causes of hypergastrinemia (eg, atrophic gastritis).
Hormone-mediated keratinocyte and dermal fibroblast proliferation occurs in _________
- acanthosis nigricans - hormone = insulin - asymptomatic
This patient with fever, right upper quadrant pain, and leukocytosis has _________ .
- acute cholecystitis - Cholecystitis is inflammation of the gallbladder that usually occurs when gallstones obstruct the cystic duct. Gallstones form due to supersaturation of bile constituents (eg, cholesterol, bilirubin), which then crystalize out of solution with other bile components (eg, mucin, calcium, proteins) to produce stones.
In ___________ , focal areas of fat necrosis, calcium deposition and interstitial edema are seen on light microscopy.
- acute interstitial pancreatitis - pancreas is grossly edematous.
Common causes of small bowel obstruction (SBO) include
- adhesions, hernias, and tumors - Small bowel obstruction (SBO), a process in which a mechanical or functional obstruction disrupts the normal flow of intestinal intraluminal contents. SBO classically causes dilation of bowel proximal to the obstruction (eg, multiple dilated small bowel loops) and decompression of bowel distal to the obstruction (eg, decompressed distal ileum). - Patients with SBO typically have abdominal pain, nausea, vomiting (usually bilious), and abdominal distension and tenderness. - Common causes of mechanical SBO include peritoneal adhesions, hernias, and tumors. Computed tomography is the diagnostic test of choice because it usually can identify the specific site of obstruction (ie, transition point), assess obstruction severity (partial vs complete), and identify potential complications (eg, bowel necrosis, perforation). - This patient's CT scan demonstrates a small bowel loop extending outside the peritoneal cavity into the left inguinal area, indicative of an inguinal hernia that has become trapped (ie, incarcerated) as the cause of SBO. Incarceration increases the risk of bowel strangulation (ie, ischemia leading to necrosis) and should prompt urgent surgical consultation.
Angina often occurs in aortic stenosis even in the absence of obstructive coronary artery disease. It results from increased myocardial oxygen demand due to
- an increase in left ventricular mass (ie, concentric hypertrophy) - increase in ventricular wall stress. Extra: Aortic Stenosis manifestations - dyspnea --> angina --> presyncope/syncope --> overt HF - mid-systolic murmur (crescendo-decrescendo) - symptoms of severe AS usually occur with exertion, as the capacity to increase stroke volume and cardiac output is limited due to the fixed left ventricular outflow obstruction - The rise in systolic wall stress increases myocardial oxygen demand while the increased diastolic wall stress reduces the coronary perfusion pressure gradient, leading to decreased myocardial perfusion
Gerstmann syndrome results from damage to the ______ of the ______ lobe and is characterized by agraphia (inability to write), acalculia (inability to carry out mathematical calculations), finger agnosia (inability to identify individual fingers on the hand), and left-right disorientation.
- angular gyrus - dominant parietal
*Medial medullary syndrome* is an ischemic stroke syndrome caused by occlusion of the _____ artery. Patients typically present with:
- anterior spinal artery Presentation: - contralateral hemiparesis (due to damage of the lateral corticospinal tract), - contralateral hemisensory loss (dorsal column medial lemniscal pathway), - ipsilateral tongue paralysis (hypoglossal nucleus).
Sheep hides can transmit
- anthrax - characterized by a necrotic skin ulcer with extensive surrounding edema and regional lymphadenopathy. - Bacillus anthracis, the causative agent, is a gram-positive, spore-forming rod; infections are quite rare in the United States.
The fourth aortic arch on the LEFT forms the ______ between the left carotid artery and ductus arteriosus.
- arch of the aorta - Abnormalities during development can result in coarctation (narrowing) of the aorta, which can present with continuous murmurs over the back due to collateral formation.
Increased _________ are indicators of hepatocellular damage, and increased __________ indicate biliary injury.
- aspartate aminotransferase and alanine aminotransferase (AST and ALT) - alkaline phosphatase and gamma-glutamyl transpeptidase Serum albumin levels, bilirubin levels, and prothrombin time are reflective of liver function and are of greatest prognostic significance in patients with cirrhosis.
Renal infarctions are most commonly caused by
- cardioembolic disease - atrial fibrillation is the greatest risk factor. - Clinical features include flank pain, nausea, vomiting, low-grade fever, and hypertension (due to renin release from hypoxic tissue). - Gross pathology demonstrates sharply demarcated, yellow-white, wedge-shaped areas with surrounding hyperemia.
The major adverse effect of trastuzumab is a risk of _________
- cardiotoxicity - Trastuzumab is a monoclonal antibody used in the treatment of breast cancer caused by tumor cells that overexpress human epidermal growth factor receptor-2 (HER2). - HER2 signaling plays a role in minimizing oxidative stress on cardiomyocytes and preserving cardiomyocyte function. Cardiotoxicity typically manifests as a decrease in myocardial contractility (myocardial stunning) without cardiomyocyte destruction or myocardial fibrosis.
In cystic fibrosis, impairment of the cystic fibrosis transmembrane conductance regulator (CFTR) protein reduces ______ secretion and increases _______ absorption by the respiratory epithelia, resulting in dehydrated mucus.
- chloride - sodium - When saline is applied to the nasal mucosa, the increased sodium absorption in patients with CF causes a more negative nasal transepithelial potential difference, which can be used to diagnose cystic fibrosis. - Chronic cough and recurrent sinusitis in a young Caucasian patient should raise suspicion for cystic fibrosis (CF). The diagnosis of CF typically is based on elevated sweat chloride concentrations, characteristic clinical findings (recurrent sinopulmonary infections, pancreatic insufficiency), and/or a positive family history. However, patients with mild mutations of the CF transmembrane conductance regulator (CFTR) gene may have normal sweat testing. In these cases, a useful diagnostic adjunct involves measuring the nasal transepithelial potential difference. - In intestinal and respiratory epithelia, the CFTR channel secretes chloride ions into the lumen and also has a tonic inhibitory effect on the opening of the epithelial sodium channel (ENaC), which decreases sodium reabsorption into the cell. This high luminal salt content helps retain water in the lumen, forming well-hydrated mucus. During the nasal transepithelial potential difference test, a saline solution is applied to the nose. Because patients with CF have increased sodium absorption via the ENaC, sodium is absorbed intracellularly but chloride in the saline solution is retained in the lumen. The higher relative amounts of negatively charged chloride on the epithelial surface result in a more negative transepithelial voltage difference.
Tumor Marker: hcg Associations: ???
- choriocarcinoma - germ cell tumor
Quick clinical tests to assess attention and concentration include:
- counting down from 100 by intervals of 3 or 7, - reciting the months of the year in reverse order - spelling "world" backwards.
Listeria monocytogenes is a facultative intracellular, gram-positive rod that most often causes febrile gastroenteritis. Pathogenesis is mediated largely by listeriolysin O, an enzyme that
- creates pores in phagosomes, which allows the bacteria to escape lysosomal destruction. - treatment involves cell mediated immunity - Pregnant women in the third trimester are at greatest risk; infection increases the risk of fetal demise, early labor, and neonatal infection. - Actin-based transcellular spread: The organism hijacks the actin-based cellular motility mechanism of host cells, which allows it to spread to adjacent cells without reentering the extracellular space. This significantly reduces exposure of L monocytogenes to antibodies and phagocytic cells. - Treatment: Ampicillin
Increased activity of the enzyme _________ has been found in many forms of colon adenocarcinoma and in inherited polyposes syndromes.
- cyclooxygenase-2 (COX-2) - This may be due to the need for COX-induced prostaglandin production, which leads to epithelial proliferation. - Regular aspirin (a COX inhibitor) intake has been associated with lower rates of colonic adenoma and adenocarcinoma, although this must be balanced against bleeding risk. - Adenomatous polyps contain dysplastic mucosa and are premalignant. They tend to develop in patients age >50 as a result of mutations in the APC tumor suppressor gene, which regulates cell growth and adhesion. - Progression to adenocarcinoma proceeds as other mutations occur in genes such as KRAS and TP53. This accumulation of gene mutations is called the "adenoma-to-carcinoma sequence."
Gastric cancer risk factors
- dietary nitrates - ETOH and Tobacco use - H pylori
What causes Hereditary Angioedema? What levels are expected to be low?
- due to C1 inhibitor deficiency - C4 levels are low (due to uninhibited cleavage of C4 by excess activated C1)
Enterotoxin production within the intestine by _________ , whose toxins cause watery diarrhea, and ________ , whose toxins cause inflammatory/bloody diarrhea
- enterotoxigenic Escherichia coli (ETEC) and Vibrio cholera - enterohemorrhagic E coli (EHEC) and Shigella
Renal cell carcinoma causes a variety of paraneoplastic syndromes:
- erythrocytosis (due to excessive erythropoietin production) - hypercalcemia (due to parathyroid hormone-related peptide).
*Radiation-induced lung injury* typically occurs following thoracic irradiation (eg, breast cancer), which damages pneumocytes and vascular endothelial cells and initiates an inflammatory response (eg, IL-1, TNFα, TGF-β). This immune response can have both acute (eg, ________ ) and delayed (eg, _______ ) effects that typically manifest with cough and dyspnea.
- exudative alveolitis, hyaline membrane formation - dense fibrosis
AE of digoxin
- fatigue - yellow-tinted vision - Hyperkalemia (Hypokalemia can precipitate toxicity tho) - Nausea/Vomiting - Diarrhea - Confusion - Arrhythmias (at toxic levels by increasing Perkinje fiber automaticity --> ventricular tacchycardia/arrhythmia)
Severe hypoglycemia causing impaired conciousness can be treated by with injectable or intranasal ________ --> increases ________
- glucagon - hepatic glycogenolysis
Glucagon increases serum glucose by increasing ______ glucose production via ______
- hepatic - glycogenolysis (breakdown of glycogen) and gluconeogenesis (production of glucose from noncarbohydrate sources). - Glucagon increases serum glucose by increasing hepatic glycogenolysis and gluconeogenesis. Glucagon also stimulates insulin secretion from the pancreas. Unlike epinephrine, glucagon has an insignificant effect on glucose homeostasis in the skeletal muscle, adipose tissue, and renal cortex. - Glucagon functions by stimulating G protein-coupled receptors on hepatocytes, increasing intracellular cAMP concentration and activating protein kinase A. This leads to activation of the key glycogenolytic enzyme, glycogen phosphorylase. It also stimulates gluconeogenesis by activating rate-limiting gluconeogenetic enzymes (eg, pyruvate carboxylase, phosphoenolpyruvate carboxykinase) and decreasing intracellular fructose-2,6-bisphosphate levels (inhibiting glycolysis).
Infection with the _________ occurs due to the ingestion of larvae from raw freshwater fish.
- human tapeworm Diphyllobothrium latum - Disease classically results in vitamin B12 deficiency and megaloblastic anemia.
The ________ is formed by the union of the right and left common iliac veins at the level of L4-L5.
- inferior vena cava - The renal arteries and veins lie at the level of L1. - The inferior vena cava returns venous blood to the heart from the lower extremities, portal system, and abdominal and pelvic viscera.
What drugs end in "-tegravir"?
- integrase inhibitors - Inhibits HIV genome integration into host cell chromosome by reversibly inhibiting HIV integrase. - Elevated creatinine kinase* and myopathy (like daptomycin) - Integration of double-stranded HIV DNA into the host cell's chromosomes is necessary to induce viral gene expression and prevent degradation of the viral genome. - ex: Raltegravir is an integrase inhibitor that disrupts HIV genome integration, preventing synthesis of viral mRNA.
Blockade of TNF-alpha (ex: via adalimumab) increases the risk of infection with pathogens controlled by the cell-mediated immune response such as:
- intracellular bacteria (eg, Mycobacterium tuberculosis), - viruses - granulomatous fungi (histoplasmosis, blastomycosis?)
Type B dissections involving the descending aorta typically originate close to the origin of the _______ . Type A aortic dissections usually originate in the ________
- left subclavian artery - sinotubular junction
The most common outcome of hepatitis C infection without antiviral treatment is
- lifelong persistent infection (chronic hepatitis C). - Of those with chronic hepatitis C, approximately 20% develop cirrhosis, and only a minority experiences complications (eg, ascites, variceal bleeding, hepatocellular carcinoma).
Age related changes to kidneys:
- loss of renal mass - loss of functional glomeruli - loss of renal blood flow - loss of responsiveness to hormones (renin, PTH)
The most common cause of complement deficiency is *autoantibodies*, such as in SLE, which activate the classical complement system after binding host antigens. Classical complement pathway activation is marked by
- low C4 and C3 levels - normal factor B levels - CH50, a measure of functional activity of the entire classical pathway (eg, sufficient C1-C9), will also be low
Diphyllobothriasis is caused by infection with a fish tapeworm and is classically linked with _______ due to _________ . Although the eggs can be seen on stool microscopy, they are distinguished by a lid-like opening (operculum). In addition, a transient skin rash would not be a feature of this disease.
- megaloblastic anemia - vitamin B12 deficiency.
In Reye's syndrome, aspirin-induced mitochondrial dysfunction causes impaired fatty acid metabolism and __________ of the liver.
- microvesicular steatosis - Vomiting and confusion from cerebral swelling [cerebral edema] can rapidly progress to coma and potentially death.
*Dystrophic calcification* is considered a hallmark of cell injury and death, occurring in all types of ______ in the setting of normal ________
- necrosis (eg, coagulative, fat, caseous, liquefactive) - calcium levels. - Dystrophic calcification in aged (or damaged) cardiac valves is thought to be the result of endothelial and fibroblast death secondary to chronic hemodynamic stress (can be accentuated by valvular abnormalities) or atherosclerotic inflammation. - Subsequent release of cellular degradation products into the valvular interstitium then promotes calcification and thickening of the valve leaflets and annulus. - These changes are often benign in elderly adults (aortic sclerosis); however, over time, progressive valvular stiffening can lead to outflow obstruction (calcific aortic stenosis).
In __________ , chalky-white areas of fat necrosis interspersed with hemorrhage are seen on macroscopic examination.
- necrotizing (hemorrhagic) pancreatitis - due to trypsin activating other proteolytic enzymes
Functions of thyroid peroxidase include
- oxidation, - organification of iodine - coupling of monoiodotyrosine (MIT) and diiodotyrosine (DIT) [coupling reaction between 2 iodized tyrosine residues] Thyroid follicular cells take up iodide (I−), which is then transported into the thyroid follicular lumen, where it is oxidized to iodine (I2). Following oxidation, in a process referred to as organification, iodine reacts with tyrosine residues in thyroglobulin to form monoiodotyrosine (MIT) and diiodotyrosine (DIT) (iodination). While still attached to thyroglobulin, DIT and MIT participate in 2 coupling reactions: The coupling of 2 DITs results in formation of thyroxine (T4); the combination of 1 DIT and 1 MIT leads to the formation of triiodothyronine (T3). Subsequently, thyroglobulin, which is now attached to multiple iodinated tyrosine compounds (ie, MIT, DIT, T3, T4), is engulfed by the thyroid follicular cells and digested within lysosomes, releasing T3 and T4 into the circulation.
Subclavian steal syndrome occurs due to severe stenosis of the proximal __________ , which leads to reversal in blood flow from the contralateral _________ to the ipsilateral _________ . Patients may have symptoms related to arm ischemia in the affected extremity (eg, exercise-induced fatigue, pain, paresthesias) or vertebrobasilar insufficiency (eg, dizziness, vertigo).
- subclavian artery - vertebral artery - vertebral artery
Tyrosine is a precursor for ...
- thyroxine - dopamine - epinephrine - norepinephrine - melanin.
What CN are in the lateral section of the medulla?
9, 10, 11
Acute viral pericarditis (which can be caused by viral infection, such as an URTI, Coxsackie A and B, Echovirus) is commonly complicated by_______ . Classic features of __________ include tachycardia and ECG findings of low voltage QRS and electrical alternans (vary in amplitude from beat to beat). Chest x-ray classically reveals an enlarged cardiac silhouette with clear lungs.
- pericardial effusion - pericardial effusion - Viral pericarditis can be complicated by pericardial effusion due to fibrinous or serofibrinous pericardial inflammation. - Symptoms of pericardial effusion may include a sensation of chest tightness or fullness and dyspnea on exertion (due to decreased diastolic ventricular filling that leads to decreased stroke volume). In addition, pericardial effusion often causes the following clinical findings: - Tachycardia to compensate for decreased ventricular filling - Low voltage QRS on ECG and diminished heart sounds to auscultation due to pericardial fluid accumulation increasing the distance between the heart and the ECG leads or stethoscope - Electrical alternans on ECG due to the swinging motion of the heart in the fluid-filled pericardial cavity, causing a beat-to-beat variation in the QRS axis - Patients with pericardial effusion classically have an enlarged, globular cardiac silhouette on chest x-ray, which occurs when progressive pericardial stretching over days to weeks (ie, subacute course) allows large volumes (eg, up to 1-2 L) of pericardial fluid to accumulate. - Clear lung fields are typically seen because the increase in pericardial pressure (due to pericardial fluid accumulation) affects the lower pressure, right-sided heart chambers more than the left-sided heart chambers. When right-sided obstruction to blood flow is greater than left-sided obstruction, pulmonary edema is unlikely to develop.
Endomysial inflammatory infiltration is found on muscle biopsy in _______ _______ is associated with perifascicular inflammation
- polymyositis - Dermatomyositis Both diseases cause proximal muscle weakness but not distal muscle hypertrophy.
Coronary dominance is determined by the coronary artery supplying the
- posterior descending artery. - The posterior descending artery originates from the right coronary artery in approximately 70%-80% of patients (right dominant), both the right coronary and left circumflex artery in 10%-20% (codominant), and the left circumflex artery in 5%-10% (left dominant). - The dominant coronary artery supplies blood to the atrioventricular (AV) node via the AV nodal artery.
The ______ forms the rough portions of the left and right atria.
- primitive atrium - The primitive atrium receives blood from the sinus venosus in the embryonic heart and transmits it to the primitive ventricle.
*Left-sided heart failure* leads to chronically elevated pulmonary venous and capillary pressures, with resulting pulmonary edema and extravasation of ______ into the alveolar parenchyma. What does this cause
- red blood cells - The iron from red blood cells is taken up by alveolar macrophages and stored as hemosiderin, appearing as brown pigment on microscopy. - Severe left ventricular systolic dysfunction is associated with an increased risk of fatal ventricular arrhythmia (ie, ventricular tachycardia or fibrillation), which was the likely cause of death in this patient.
The right ventricle (RV) is relatively protected from myocardial infarction (MI), and contractile function of the RV usually returns to normal following MI. Factors contributing to this protection include:
- relatively small muscle mass with high capacity to increase oxygen extraction, - perfusion throughout the cardiac cycle [systole + diastole] [LV is during diastole only, and it has less developed collateral circulation --> RV has more developed collateral circulation and is more dependent on it than the LV] - heightened ischemic preconditioning. Extra: - The large muscle mass of the *LV* necessitates higher oxygen extraction at rest, with relatively little capacity to increase oxygen extraction during periods of ischemia.
Fibromuscular dysplasia can cause
- renal artery stenosis - cerebrovascular involvement (headache, stroke, hemorrhage) - extremity claudication
Symptoms of renal artery stenosis include
- resistant hypertension, - recurrent flash pulmonary edema - chronic kidney disease.
Pulmonary berylliosis closely resembles ______
- sarcoidosis (nodular infiltrates, enlarged lymph nodes, noncaseating granulomas) - Beryllium is used in the aerospace manufacturing and nuclear weapon industries.
The ductus arteriosus is derived from the
- sixth embryonic aortic arch (along with the pulmonary arteries) - A patent ductus arteriosus (PDA) causes left-to-right shunting of blood that can be heard as a continuous murmur over the left infraclavicular region. - *Indomethacin (a PGE2 synthesis inhibitor)* can be used to close a PDA in premature infants, but surgical ligation is often necessary in older patients.
AE of Finasteride
- slow onset of symptom relief - can cause gynecomastia (because less T converted to DHT --> increased T levels available to be converted to estrogen) --> can prevent with *Tamoxifen* - Androgen deficiency effects: decreased libido, erectile dysfunction, decreased ejaculatory volume
The Jarisch-Herxheimer reaction is an acute inflammatory reaction that occurs within hours of treatment for ___________ . The rapid lysis of spirochetes releases _________ into the circulation and causes acute fever, rigors, and myalgias, or rash progression in secondary syphilis
- spirochetal infections (eg, syphilis, lyme disease, leptospirosis, or bartonella) - inflammatory bacterial lipoproteins
Prognosis of colorectal adenocarcinoma is directly related to
- stage of the tumor, not to the grade! - stage = depth of invasion - grade = level of differentiation (low grade = well differentiated)
Which strep is pyrrolidonyl arylamidase (PYR) positive?
- strep pyogenes (GAS; bacitracin sensitive; can cause Post strep GN)
Bladder cancer risk factors
- tobacco smoke - Occupational exposures (rubber, plastics, aromatic amine containing dyes, textiles, leathers) - Cyclophosphamide therapy (eg, for lymphoma, autoimmune disorders) also increases the risk. - In Africa and the Middle East, infection with Schistosoma haematobium is associated with multiple cell types of bladder cancer, including UBC and squamous cell carcinoma.
Renal cancer risk factors
- tobacco smoke - obesity - HTN
Treatment for pthirus pubis
- topical permethrin cream to the affected area. Permethrin blocks parasite sodium ion conduction in nerve cell membrane channels and results in louse paralysis and death. - Other treatment: pyrethroids, malathion, or ivermectin lotion, and nit combing. - Children with head lice can be treated at home without interrupting school attendance.
The ascending aorta develops from the _________ , which also gives rise to the pulmonary trunk.
- truncus arteriosus - A portion of the aortic arch develops from the fourth branchial (pharyngeal) arch. - The pulmonary trunk is derived from the truncus arteriosus. Neural crest cell migration helps partition the truncus arteriosus into the 2 great arteries (aorta and pulmonary artery) by causing fusion and twisting of the truncal and bulbar ridges. This process results in the normal spiral relation between the aorta and pulmonary artery. Failure of this process results in transposition of the great vessels and tetralogy of Fallot.
The lepromin skin test will be positive in patients with _______ as they exhibit a strong CD4+ TH1 cell-mediated immune response to ________ . Patients with ________ will test negative due to their weak TH1 cell-mediated immune response.
- tuberculoid leprosy - Mycobacterium leprae - lepromatous leprosy
In early embryonic development, the body's veins fall into 3 main groups: umbilical, vitelline, and cardinal veins. The ______ degenerates, the ______ form the portal system, and the _______ form constituents of the systemic venous circulation.
- umbilical vein - vitelline veins - cardinal veins
Staghorn calculi are large magnesium ammonium phosphate (struvite) stones that fill the renal calyces. Although they may cause hematuria, they are typically seen in patients with recurrent urinary tract infections by ________ -producing bacteria (eg, _______ )
- urease - Proteus, Klebsiella
Severe _________ characteristically causes hypokalemic, hypochloremic metabolic alkalosis.
- vomiting - The metabolic alkalosis is initiated by loss of gastric H+ from the body, worsened by hypovolemia-induced activation of the renin-angiotensin-aldosterone system, and perpetuated by profound gastric and renal losses of Cl− that lead to hypochloremia and impaired renal HCO3− excretion [elevated bicarb, low Cl and Na] - Hypokalemia primarily results from aldosterone-mediated renal K+ losses [low K]
What is total anomylous venous return and what is the resultant O2 pattern?
- which the pulmonary veins (ie, oxygenated blood) drain into the RA rather than the LA. - increased right-sided and decreased left-sided SaO2
Besides pts age 65+ who have a work history, Medicare also covers
- younger individuals with disabilities, - end-stage renal disease, = amyotrophic lateral sclerosis (ALS)
A phase ____ trial assesses the pharmacokinetics, pharmacodynamics, and safety profile (eg, adverse events, toxicity) of a new treatment in humans. It is usually conducted on a small number of healthy subjects
1
Type ____ muscle fibers (slow-twitch or red fibers) primarily use *oxidative phosphorylation* and contain *high quantities of lipids, myoglobin, and mitochondria*. They specialize in sustained, *low force* contraction, and their function is amplified by *endurance training*.
1
HLA-A, HLA-B, and HLA-C genes encode MHC class ____ molecules, which are expressed on ______ cells
1 nucleated cells - after a cytosolic antigen has been transported into the endoplasmic reticulum and loaded onto the MHC class I molecule
Prerenal Azotemia: 1) BUN/Cr 2) Fractional Excretion of Na 3) Urine Osmolality 4) Microscopy
1 = > 20 2 = < 1 % 3= > 500 mOsm 4 = Hyalin Casts
Erythema multiforme: 1) Causes 2) Pathogenesis 3) Appearance
1) Causes: - *Herpes (MCC)* - Mycoplasma pneumonia - Sulfa drugs - NSAIDs - Phenytoin 2) Pathogenesis - Epithelial injury by skin-homing CD8+ T-lymphocytes --> attack basal cells of cutaneous and mucosal epithelia 3) Appearance: Target skin lesions
The splenic *red pulp* is important for:
1) Destroying aged and abnormal erythrocytes (eg, spherocytes) and serving as an emergency store of blood cells and platelets that can be delivered into the circulation when needed. 2) Clearance of circulating bacteria that become lodged in the cords. Macrophages then present captured antigens to the B- and T-cells residing in the splenic white pulp to generate an active immune response.
What drugs are GnRH agonists used to treat prostate cancer? What drug is used to prevent the LH/FSH surge from the GnRH agonist?
1) Leuprolide and Goserelin 2) Flutamide [competitive antagonist at androgen receptor]
Kussmaul sign is a paradoxical increase in jugular venous pressure on inspiration. It occurs because of impaired right-sided diastolic filling in conditions such as
1) constrictive pericarditis (a result of chronic pericarditis) - A pericardial knock is a brief, high-frequency, precordial sound heard in early diastole (shortly after S2) in patients with constrictive pericarditis. It occurs earlier than S3 and may be confused with the opening snap of mitral stenosis. 2) restrictive cardiomyopathy 3) tricuspid stenosis.
Fibrates (eg, ____1_____ and _____ ) work by activating ____2___ , which increases the synthesis of _____3____ (and induces synthesis of ____4__ ), which increases the CLEARANCE of ____5____ . An adverse effect is _____6____
1) fenofibrate, gemfibrozil 2) peroxisome proliferator-activated receptor-alpha (PPAR-α) 3) lipoprotein lipase 4) HDL 5) Triglycerides 6) Cholesterol gallstones [via inhibition of cholesterol 7-alpha hydroxylase] (and increases risk of myopathy with statins) - Fibrate medications (eg, fenofibrate, gemfibrozil) inhibit cholesterol 7α-hydroxylase, which catalyzes the rate-limiting step in the synthesis of bile acids. The reduced bile acid production results in decreased cholesterol solubility in bile and favors the formation of cholesterol gallstones.
RBCs that have projections of varying size at irregular intervals are called what? What conditions are they seen in?
1. Acanthocytes (spur cells) 2. - Liver disease - Abetalipoproteinemia - Vit E deficiency
Pathogenesis of Neiserria meningitis (meningococcal) infection:
1. Aerosol droplets --> Naso*pharyngeal* colonization 2. Invasion of epithelium 3. Invasion of *blood* 4. Further dissemination (ex: CSF)
Which drugs can cause QT prolongation --> torsades?
1. Class 1A (Quinidine, Procainamide, Disopyramide) 2. Class 3 (K channel blockers; Sotalol, Amiodarone, Ibutilide, Dofetilide) 3. Haloperidol, Respiridone 4. Macrolides, Fluoroquinolone 5. Methadone 6. Anti-emetics: Odansatron, Metoclopramide 7. Azoles (fluconazole, Itraconazole, etc.)
RBCs with small, uniform projections are called what? What conditions are they seen in?
1. Echinocytes (Burr cells) 2. - Liver disease - ESRD - Pyruvate kinase deficiency
What are the anti-staphylococcal penicillins (resistant to b-lactamase)?
1. oxacillin 2. nafcillin 3. dicloxacillin (PO) - used for Methicillin-Sensitive Staph Aureus - S aureus strains that are resistant to oxacillin, nafcillin, and methicillin have been historically termed MRSA, but they are also resistant to all β-lactam agents, including penicillin, cephalosporins (except ceftaroline, a fifth-generation cephalosporin), and carbapenems. Methicillin (nafcillin) resistance is typically mediated by alterations in the structure of penicillin-binding proteins (PBP)
Rheumatoid arthritis causes progressive joint destruction involving the hands, wrists, elbows, and knees. _________ involvement can lead to spinal instability and cord compression.
Cervical spine
What CN are in the medial section of the medulla?
12
Which drug is used to treat hyperthyroidism in the first trimester of pregnancy? Second and third? Why?
1st trimester: Propylthiouracil [due to teratogenic effects of Methimazole (aplasia cutis)] 2/3rd trimester: Methimazole [due to hepatotoxic effects of Propylthiouracil]
Type ____ muscle fibers (fast-twitch or white fibers) primarily use *glycolysis* and specialize in *rapid bursts* of high force contraction. Their function is amplified by *resistance training*.
2
A phase ____ clinical trial assesses treatment efficacy and adverse effects in a small number of affected subjects (ie, those with the disease of interest).
2 - The results are often compared with those of previous clinical trials (ie, historic controls) to determine the potential benefit of the new treatment.
HLA-DP, HLA-DQ, and HLA-DR genes encode MHC class _____ molecules, which are expressed on ______ cells
2 antigen-presenting cells (eg, B cells, macrophages) - after an extracellular antigen has been loaded onto the MHC class II molecule in an acidified lysosome.
By age _____ , a child is expected to play imaginatively in parallel with others, speak in simple sentences, *copy a circle, use utensils*, and ride a tricycle.
3 - 3-year-olds engage in imaginative play and play in parallel but *not cooperatively* with others (social). - Toilet training often begins at age 2 or 3.
Henoch-Schönlein purpura is an IgA-mediated type _____ hypersensitivity reaction in children that generally follows infection. Deposition of circulating IgA-containing immune complexes in small vessels results in systemic vasculitis. Common manifestations include palpable lower-extremity purpura, abdominal pain, arthralgias, and hematuria.
3
A phase ____ trial assesses the safety and effectiveness of a new treatment compared to a standard treatment (or placebo); they usually involve ≥2 groups of affected subjects that are assigned to different treatment interventions.
3 - For example, a phase III study would have a treatment arm (experimental group) receiving tandutinib in combination with bevacizumab and a control arm receiving bevacizumab alone. The effectiveness and toxicity of the treatments would then be compared to determine the superior option. In contrast, this study did not have its own control group.
What CN are in the medial section of the midbrain?
3 and 4
Adjustment disorder involves emotional or behavioral symptoms occurring within ______ of an identifiable stressor.
3 months The diagnosis is indicated when the patient has significant distress and impairment but does not meet full criteria for another mental disorder. Symptoms in an adjustment disorder must be distressing and impairing (eg, this patient seeks medical attention for insomnia and is socially isolative) but are insufficient to meet full criteria for another mental disorder. - A normal stress response is differentiated from an adjustment disorder by milder symptoms, lack of marked distress
The hepatitis C virus is genetically unstable because it lacks proofreading _____ activity in its RNA polymerase.
3' → 5' exonuclease - Its envelope glycoprotein sequences also contain a hypervariable region prone to frequent genetic mutation. - 5' → 3' exonuclease activity allows DNA polymerase I to engage in nick translation, which is important for both DNA repair and removal of RNA primers during replication. This feature is not the cause of instability in HCV.
What CN are in the lateral section of the pons?
5, 7, 8
Male neonates with ______ deficiency are born with feminized external genitalia that typically masculinize at puberty.
5α-reductase - A small phallus and hypospadias are common. - the internal genitalia develop normally under the influence of testosterone, but the external genitalia do not develop properly due to the lack of DHT, resulting in male pseudohermaphroditism. The genitalia at birth can range from a small phallus with hypospadias to ambiguous or female-type genitalia. Such children are often raised as females until they reach puberty, when high levels of testosterone and the action of 5α-reductase type 1 result in masculinization with male-pattern muscle mass, voice deepening, penile and scrotal growth, and testicular descent.
What CN are in the medial section of the Pons?
6
When is iron supplementation recommended for babies?
> 4 months
Stable angina pectoris results from myocardial oxygen demand-supply mismatch and manifests as chest pressure, tightness, or pain that is reliably produced by exertion and relieved by rest. It most commonly occurs due to a fixed atherosclerotic plaque obstructing _______ of the coronary artery lumen that limits blood flow during exertion
>70%
Gilbert Syndrome
A genetic mutation results in *reduced enzymatic activity of UDP glucuronosyltransferase* and therefore decreased bilirubin conjugation. Triggers associated with increased bilirubin production (eg, stress [febrile illness, fasting, dehydration, vigorous exercise, menstruation, surgery], illness, hemolysis) result in episodic exacerbations of indirect hyperbilirubinemia, as seen in this patient. Because bilirubin *excretion into the bile duct is normal* in Gilbert syndrome, *hepatocyte bilirubin storage* is also normal, as is liver histology - ↑ Unconjugated bilirubin (ie, indirect hyperbilirubinemia) - Normal CBC, blood smear, reticulocyte count - Normal AST, ALT, alkaline phosphatase
_______ causes secondary amenorrhea through obstruction from scarring of the uterine cavity. This is typically a sequela of uterine infection (eg, postpartum endometritis) or procedures (eg, dilation and curettage).
Asherman syndrome
_______ fibers are thin, myelinated nerve fibers whose free nerve endings detect temperature and nociceptive stimuli. They are associated with acute (sharp) pain and constitute the afferent portion of the reflex arc that mediates withdrawal from noxious stimuli (e.g., retracting the hand away from a hot stove).
A-delta
_________ is caused by reduced numbers of inhibitory ganglion cells in the esophageal wall.
Achalasia - Esophageal manometry in achalasia shows decreased amplitude of peristalsis in the mid esophagus, with increased tone and incomplete relaxation at the lower esophageal sphincter.
The best and most reliable auscultatory indicator of the degree of mitral stenosis is the
A2-OS interval - A shorter interval indicates more severe stenosis. - murmur increases leg raising (no change with hand grip) - Other auscultatory findings can include a diastolic rumbling murmur with presystolic accentuation due to left-atrial contraction.
________ often causes diarrhea and malabsorption (eg, iron deficiency anemia). The earliest histologic finding is duodenal intraepithelial lymphocytosis; crypt hyperplasia and villous blunting develop later.
Celiac disease
Treatment of congenital adrenal hyperplasia due to 21-hydroxylase deficiency involves low doses of exogenous corticosteroids to suppress excess _________ secretion, which reduces production of androgens by the adrenal cortex.
ACTH
Normal effect of ADH and how it differs in SIADH:
ADH: - secreted in volume deprivation - causes increase in water reabsorption --> low serum osmolality and hyponatremia due to increase in serum water - concentrated and high urine osmolality SIADH - ADH secreted in excess --> excess water volume in serum sensed --> release of natriuretic peptide --> Na not reabsorbed/secreted into urine --> Hypernatremia - still have high urine osmolality due to ADH and low serum osmolality (but sodium is now high in urine)
blood supply to lateral part of pons
AICA
What problem with the esophagus can Chagas cause?
Achalasia - causes secondary achalasia due to destruction of the submucosal (Meissner) and myenteric (Auerbach) plexus. - Other manifestations can include nonischemic cardiomyopathy and megacolon. In addition, patients are at higher risk for esophageal cancer
FAP gene mutation
APC [tumor suppressor gene; normally destroys beta-catenin]; Autosomal dominant - look for a ton of polyps on colon, etc. - 100% colon cancer risk
Where is the block usually seen in Mobitz type 1?
AV node
______ is located in the right atrium near the septal cusp of the tricuspid valve.
AV node
Which Nucleotide Reverse Transcriptase Inhibitor (NRTI) is contraindicated if patient has HLA-B*5701 mutation due to high risk of hypersensitivity?
Abacavir - tenofovir is the only nucleotide, rest are nucleosides [nucleosides can cause lactic acidosis]; all need to be activated by phosphorylation
________ decreased amplitude of peristalsis in the mid esophagus, and increased tone and incomplete relaxation at the LES. Patients experience dysphagia, regurgitation, and retrosternal chest pain. Barium esophagram typically shows dilation of the esophagus with distal narrowing.
Achalasia
Premature placental separation from uterus =
Abruptio placenta - Risk factors: -- Previous abruption -- Maternal HTN/pre-eclampsia -- Smoking -- Cocaine -- Abnormal uterus [bicornuate; prior c-section] -- Trauma [motor vehicle accident]
- *Sudden-onset painful* vaginal bleeding - Abdominal or back pain - High-frequency contractions - Tender, firm uterus
Abruptio placenta - posterior abruption may have little or no bleeding - occurs in 3rd trimester
________ is a diffuse increase in thickness of the stratum spinosum (prickle cell layer) between the granular cell layer and the basal layer of the epidermis
Acanthosis
What diabetic drugs are alpha-glucosidase inhibitors?
Acarbose, Meglitol - Acarbose inhibits alpha-glucosidase in the intestinal brush border, impairing the hydrolysis of polymeric carbohydrates and leading to decreased postprandial glucose absorption. - Acarbose indirectly decreases endogenous insulin (and C-peptide) secretion by reducing postprandial hyperglycemia.
______ reduce the rate of spontaneous depolarization in cardiac pacemaker cells by prolonging phase 4.
Acetylcholine and Adenosine - The phase 4 slow depolarization in cardiac pacemaker cells occurs due to the closure of repolarizing K+ channels, the slow influx of Na+ through funny channels, and the opening of T-type Ca2+ channels. - Adenosine interacts with A1 receptors on the surface of cardiac cells, activating potassium channels and increasing potassium conductance, causing the membrane potential to remain negative for a longer period. Adenosine also inhibits L-type Ca2+ channels, further prolonging the depolarization time. These actions result in a transient slowing of the sinus rate and an increase in atrioventricular (AV) nodal conduction delay. - Adenosine is useful in the termination of paroxysmal supraventricular tachycardia. - Acetylcholine behaves similarly by increasing outward K+ conductance while decreasing inward Ca2+ and Na+ currents during phase 4.
_________ are pedunculated outgrowths of normal skin. They are typically seen in areas of friction (eg, neck, axilla, inframammary, groin) of patients with obesity and diabetes mellitus.
Acrochordons (skin tags)
___________ is an acute inflammation of the gallbladder in the absence of gallstones. It typically occurs in critically ill patients (eg, those with sepsis, severe burns, trauma, immunosuppression) due to gallbladder stasis and ischemia. Clinical findings may be subtle and include fever, right upper quadrant pain, and leukocytosis
Acute acalculous cholecystitis
_______ is a life-threatening infection characterized by fever, right upper quadrant pain, and jaundice (Charcot triad);
Acute cholangitis - hypotension and altered mental status (Reynold pentad) occur in severe cases. - life-threatening infection that typically develops in the setting of biliary obstruction, which enables bacteria to proliferate within the biliary tree. Obstruction can occur in a variety of settings (eg, malignant biliary obstruction, biliary stricture) but is most commonly caused by a calculous obstruction of the common bile duct (ie, choledocholithiasis). - Acute cholangitis typically develops in the setting of biliary obstruction; common etiologies include gallstones, malignancy, and strictures
Transplant rxn: - Recipient T cells react to graft (via HLA) - Cell-mediated immune process - CD8 T cells very important* - Biopsy: infiltrates of *lymphocytes*/mononuclear cells
Acute rejection - type 2/3 HS rxn - Treatable with immunosuppression
Alveolar hyaline membranes are seen in _______
Acute respiratory distress syndrome - The pulmonary edema tends to reduce lung compliance, causing a restrictive flow-volume pattern - Acute eosinophilic pneumonia (AEP) is an idiopathic form of pneumonia caused by eosinophilic invasion of the lung tissue, often with hyaline membranes, a nonspecific finding of inflammatory fibrinous edema. ARDS also features prominent hyaline membranes, but the inflammation is driven by neutrophils rather than eosinophils.
Clinical features of Rheumatic Fever (caused by Group A Strep pharyngitis)
Acute/subacute - Migratory arthritis - Pancarditis (mitral regurgitation) - Sydenham chorea Chronic - Mitral stenosis - Prevention: Prompt treatment of streptococcal pharyngitis with penicillin - Pathogenesis: - Occurs 2-4 weeks after acute group A streptococcal pharyngitis - Molecular mimicry: Anti-streptococcal antibodies attack cardiac & neuronal antigens
Bacterial endocarditis
Acute—S aureus (high virulence). Large vegetations on previously normal valves A . Rapid onset. Subacute—viridans streptococci (low virulence). Smaller vegetations on congenitally abnormal or diseased valves. Sequela of dental procedures. Gradual onset. Associated with glomerulonephritis, septic arterial or pulmonary emboli. May be nonbacterial (marantic/thrombotic) 2° to malignancy, hypercoagulable state, or lupus FROM JANE with ♥: Fever Roth spots Osler nodes Murmur Janeway lesions Anemia Nail-bed hemorrhage Emboli Requires multiple blood cultures for diagnosis. If culture ⊝, most likely Coxiella burnetii, Bartonella spp. *Mitral valve is most frequently involved* *Tricuspid valve endocarditis is associated with IV drug abuse (don't "tri" drugs)* Associated with S aureus, Pseudomonas, and Candida. S bovis (gallolyticus) is present in colon cancer, S epidermidis on prosthetic valves. Native valve endocarditis may be due to HACEK organisms: Haemophilus Aggregatibacter [formerly Actinobacillus] Cardiobacterium Eikenella Kingella
________ is the abnormal presence of endometrial glands and stroma within the uterine myometrium.
Adenomyosis
- Woman > 40 yo - Risk factors: Multiparity and Prior uterine surgery (C-section) - *Dysmenorrhea (painful uterine bleeding)* - *Regular, heavy menses (increased uterine bleeding during cycle)* - Uniformly enlarged uterus
Adenomyosis - Treatment: Hysterectomy
_________ interacts with A1 receptors on cardiac cells and activates potassium channels, increasing potassium conductance. It causes a transient conduction delay through the atrioventricular (AV) node and is used for acute termination of paroxysmal supraventricular tachycardia (PSVT).
Adenosine - has a very brief duration of action
_________ is a polyene antifungal that binds ergosterol in the fungal cell membrane and leads to pore formation and cell lysis.
Amphotericin B [Polyenes (eg, amphotericin B, nystatin)] - supplement with K and Mg
The __________ mosquitoes can transmit the viruses that cause dengue fever and chikungunya
Aedes aegypti
Pseudomonas aeruginosa
Aeruginosa—aerobic; motile, catalase ⊕, gram ⊝ rod. Non-lactose fermenting. Oxidase ⊕. Frequently found in water. Has a grape-like odor. PSEUDOMONAS is associated with: - Pneumonia, - Sepsis, - Ecthyma gangrenosum, - UTIs (especially in pts with indwelling catheters)*** - Diabetes, - Osteomyelitis, - Mucoid polysaccharide capsule [may contribute to chronic infection in CF pts due to biofilm formation] - Otitis externa (swimmer's ear), - Nosocomial infections (eg, catheters, equipment), - Addicts (drug abusers), - Skin infections (eg, hot tub folliculitis, wound infection in burn victims). Treatments include "CAMPFIRE" drugs: - Carbapenems - Aminoglycosides - Monobactams - Polymyxins (eg, polymyxin B, colistin) - Fluoroquinolones (eg, ciprofloxacin, levofloxacin) - ThIRd- and fourth-generation cephalosporins (eg, ceftazidime, cefepime) - Extended-spectrum penicillins (eg, piperacillin, ticarcillin)
At what age do children understand gender/ can develop gender dysphoria?
Age 4 *Important:* - Although children understand the concept of gender by age 4, it is normal for them to explore activities culturally associated with the opposite gender (ex: boys playing with dolls). In contrast, gender dysphoria is diagnosed when there is marked distress associated with a prolonged and intense feeling that one is a different gender from one's birth sex. - Children usually know their gender by age 4 and understand that it is permanent by age 5-6. - Playing with dolls is consistent with normal explorative play, not gender dysphoria. Further evaluation and professional support might be warranted in this child if he had a more persistent desire to be the opposite sex or disliked his own genitalia.
The *isolated systolic* hypertension commonly seen in elderly patients results from _______ and __________
Age-related stiffening (ie, replacement of elastin with collagen) Reduced compliance of the aorta and other large arteries. - The aortic lumen slightly increases (not decreases) in diameter with age. Nonetheless, it is the compliance of the large arteries (rather than the diameter) that affects blood pressure. The diameter of the small arteries (ie, arterioles) determines systemic vascular resistance and is a primary determinant of DBP.
Treatment for Enterobius vermicularis?
Albendazole, Mebendazole, and Pyrantel pamoate
_________ directly inhibit the mineralocorticoid receptor, resulting in decreased formation and activity of epithelial sodium channels and Na+/K+-ATPase pumps
Aldosterone antagonists (ie, spironolactone, eplerenone) [K sparing diuretics]
In a patient with asymptomatic LV systolic dysfunction, what do you expect the levels of Angiotensin II, NE, and ANP to be (increased/decreased)?
All increased. HF --> increase NE and AT II --> increased Fluid volume --> ANP released (but HF still causes NE + AT II to be released)
HbA2
Alpha 2 - Delta 2
Which receptor decreases insulin secretion?
Alpha-2 (and somatostatin-2) - Beta-2, M3, Glucagon-like peptide-1, and glucagon all increase insulin secretion
_________ directly inhibit the epithelial sodium channel, preventing sodium from entering the principal cell, which reduces the electrochemical gradient (ie, negative luminal charge) that helps drive potassium secretion.
Amiloride and Triamterene [K sparring diuretics]
Which drug that prolongs the QT interval has a low incidence of torsades?
Amiodarone
Cytologic features of _______ thyroid cancer include markedly pleomorphic cells, including irregular giant cells and biphasic spindle cells
Anaplastic thyroid cancer - Anaplastic thyroid cancer is an aggressive tumor with a very poor prognosis. It is most common in older patients (age >60).
Cytologic features of ____________ include markedly pleomorphic cells, including irregular giant cells and biphasic spindle cells.
Anaplastic thyroid cancer - an aggressive tumor with a very poor prognosis. It is most common in older patients (age >60)
What drugs are aromatase inhibitors?
Anastrozole, Letrozole, Exemestane - Aromatase inhibitors decrease the synthesis of estrogen from androgens, suppressing estrogen levels and slowing progression of ER-positive tumors. - less effective in pre-menopausal women
________ typically present at birth with a female phenotype or ambiguous genitalia (and a 46,XY karyotype)
Androgen receptor defects
What hormone stimulates acne?
Androgens - high circulating levels of androgens = acne
Failure of rostral neuropore to close --> no forebrain, open calvarium. Clinical findings: polyhydramnios (no swallowing center in brain).
Anencephaly - Neural Tube defects: Neuropores fail to fuse (4th week) --> persistent connection between amniotic cavity and spinal canal. Associated with maternal diabetes and folate deficiency. Increased α-fetoprotein (AFP) in amniotic fluid and maternal serum (except spina bifida occulta = normal AFP). Increased acetylcholinesterase (AChE) in amniotic fluid is a helpful confirmatory test.
Malignant liver tumor of endothelial origin; associated with exposure to arsenic, vinyl chloride.
Angiosarcoma
Carcinogen: Vinyl chloride. thorotrast Cancer: ???
Angiosarcoma - *V*inyl chloride = Used to make P*V*C pipes (plumbers) - *Angiosarcoma tumors express CD31 [endothelial cell marker]*
Chronic lymphedema is a risk factor for the development of cutaneous ________
Angiosarcoma (also known as Stewart-Treves syndrome)
________ characterized by simultaneous erosion of bone and new bone formation.
Ankylosing spondylitis
blood supply to medial part of medulla
Anterior spinal artery (ASA)
antibody for dermatomyositis
Anti-Jo-1
Serologic markers for Sjogren syndrome
Anti-Ro (SSA) and Anti-La (SSB) - Patients typically have severe dry mouth (xerostomia) and dry eyes (keratoconjunctivitis sicca); vaginal gland involvement is also common. - Often associated with other autoimmune disorders (ex: Rheumatoid arthritis)
What antibody is found in CREST syndrome?
Anti-centromere - CREST syndrome (limited scleroderma) manifests with calcinosis, Raynaud's phenomenon, esophageal dysmotility, sclerodactyly and telangiectasias.
Normal aortic and LV pressures
Aortic = 120/80 LV = 120/10 - The hemodynamic changes in AR are evident on cardiac catheterization and include reduced aortic diastolic pressure and elevated left ventricular (LV) diastolic pressure due to backflow of blood during diastole. In addition, aortic and LV systolic pressures are increased due to high stroke volume and a compensatory increase in cardiac contractility. [aorta ~160/60; LV ~160/20]
______ classically presents with severe retrosternal pain that radiates to the back.
Aortic dissection - Develops when overwhelming hemodynamic stress leads to tearing of the aortic intima with blood subsequently dissecting through the aortic media. The resulting intramural hematoma can extend both proximally and distally and can compress major arterial branches and impair blood flow. - As the dissecting intramural hematoma spreads along the aortic wall, it can compress major arterial branches. This patient's brachial *blood pressure discrepancy* suggests compromise of the brachiocephalic trunk servicing his right arm.
_______ occurs when hemodynamic stress leads to an intimal tear
Aortic dissection - Develops when overwhelming hemodynamic stress leads to tearing of the aortic intima with blood subsequently dissecting through the aortic media. The resulting intramural hematoma can extend both proximally and distally and can compress major arterial branches and impair blood flow. ______ classically presents with severe retrosternal pain that radiates to the back. - As the dissecting intramural hematoma spreads along the aortic wall, it can compress major arterial branches. This patient's brachial *blood pressure discrepancy* suggests compromise of the brachiocephalic trunk servicing his right arm.
_______ is the most common complication of bicuspid aortic valves
Aortic stenosis
______ deficiency presents with virilization of female infants; male patients are not affected phenotypically.
Aromatase [it converts Testosterone --> Estrogen, so males won't be effected]
How are Tidal volume, Respiratory rate, and dead space related?
As Tidal volume increases, respiratory rate [minute ventilation] and dead space decrease (and vice versa)
_________ is characterized by pleural plaques (focal pleural thickening, typically with calcifications).
Asbestos-related pleural disease - Common occupational exposures include shipbuilding, insulation manufacturing and application, and drywall application. - Most affected patients remain asymptomatic for 20-30 years following initial exposure.
Histopathology of ________ demonstrates diffuse interstitial fibrosis and *ferruginous bodies*
Asbestosis - Ferruginous bodies = translucent fibers coated with a golden iron-containing material ; Asbestos fibers can be differentiated from other ferruginous bodies (eg, carbon, talc) by their translucent fiber core. - Pleural disease (eg, plaques, benign effusions) is common - Asbestosis is a pneumoconiosis that occurs with inhalation of asbestos fibers, most commonly in patients with occupational exposure (eg, insulation installation, shipbuilding, pipe work).
Occupational exposure (eg, mining, shipbuilding, insulation installation) are at increased risk for _______
Asbestosis/Mesothelioma
CD4 count < 100
Aspergillus - hemoptysis, pleuritic pain - cavitation or infiltrates on chest imaging Bartonella spp - bacillary angiomatosis - biopsy with neutrophillic inflammation Candida albicans - esophagitis CMV - CREEP: Colitis, Retinitis, Esophagitis, Encephalitis, Pneumonitis - Owl eye inclusion bodies - cotton wool spots on fundoscopy - linear ulcers on endoscopy - CD4 < 50? Cryptococcus neoformans - meningitis - encapsulated yeast on india ink Cryptosporidium - chronic, watery diarrhea EBV - B cell lymphoma [non-hodgkin, CNS) - CNS lymphoma --> ring enhancing lesion may be solitary (vs toxoplasmosis) Toxoplasmosis gondii - multiple ring enhancing lesions
_______ is a monomorphic fungus with only a mold form. It is seen in tissue as septate hyphae with acute-angle V-shaped branching.
Aspergillus fumigatus
________ occurs when a family member or other caregiver helps the patient in making a medical decision (but does not make the decision for the patient).
Assisted decision-making - Common scenarios include when patients have intellectual disability or a potentially reversible impairment in decision-making capacity (eg, fluctuating mental illness [schizophrenia]).
Fibroblasts synthesize what collagen for wound healing?
At first type 3 collagen, but that is later replaced by type 1 collagen during the maturation phase (3 weeks -1 to 2 years; involves extensive collagen cross-linking as well)
- Ataxia (cerebellar atrophy) - Telangiectasia - Repeated sinus/respiratory infections - High risk of cancer (lymphomas) - *Increased AFP* - *Low IgA*
Ataxia Telangiectasia - Repeated infections because low IgA/IgG
- cerebellar ataxia - oculocutaneous telangiectasias - repeated sinopulmonary infections - increased incidence of malignancy
Ataxia-telangiectasia
________ is an autosomal recessive disorder characterized by DNA hypersensitivity to ionizing radiation
Ataxia-telangiectasia
- Decreased or absent breath sounds - Decreased tactile fremitus - Dullness to percussion
Atelectasis
_______ is the major pathogenic contributor to atrial fibrillation.
Atrial remodeling (can occur due to normal aging) - The development of atrial fibrillation is primarily driven by both structural and electrical conduction changes in the atrial myocardium - Age and comorbidities that cause atrial dilation (eg, hypertension, heart failure, mitral valve disease) cause atrial structural changes that predispose to atrial fibrillation development. - In addition, age and previous atrial fibrillation cause atrial conduction system changes that further propagate atrial fibrillation.
Diffuse cerebral edema can result from
too-rapid correction of hypernatremia
Micturition reflex
Autonomic spinal reflex mediated by both sensory and motor fibers from nerve centers at the S2-S4 levels. Parasympathetic stimulation causes detrusor muscle contraction and internal urethral sphincter relaxation. Sympathetic fibers cause internal sphincter contraction and also help with sensing a full bladder.
Inheritance pattern of MEN syndrome
Autosomal Dominant
Amyloid transthyretin (ATTRm) (mutated) and Amyloid transthyretin (ATTRwt) (wild-type) are associated with which disease conditions?
Autosomal Dominant Inheritance / Age-related deposition
_________ is a condition characterized by multiple renal, pancreatic, and hepatic cysts.
Autosomal Dominant Polycystic Kidney Disease
Wilson Disease inheritance/Mutation
Autosomal Recessive ATP7B Gene on Chromosome 13 Change of histidine to glutamine (H1069Q) - "Wilson, look at HIS --> Gluts" Copper transporting P-type ATPase is defective
Ataxia Telangiectasia inheritance pattern/chromosome
Autosomal Recessive ; Chromosome 11
Alpha-1-anti-trypsin deficiency inheritance pattern
Autosomal co-dominant
Osteogenesis imperfecta inheritance
Autosomal dominant (with dominant negative effect)
VHL inheritance/chromosome
Autosomal dominant; chromosome 3 - pVHL ubiquitinates hypoxia- inducible factor 1a. - VHL = tumor suppressor gene
_________ presents at birth or during the first year of life with bilateral flank masses. Cysts are formed by dilated distal tubules and collecting ducts. Abdominal ultrasonography demonstrates enlarged kidneys at birth and also shows cysts if they are >1 cm in diameter.
Autosomal recessive polycystic kidney disease (ARPKD)
_______ is a maladaptive pattern of behavior characterized by social inhibition, feelings of inadequacy, and fear of embarrassment and rejection.
Avoidant personality disorder
Medicare Part ____ covers select outpatient services + medical devices
B
In ________ , ultrasound demonstrates a shrunken, fibrosed gallbladder.
Chronic cholecystitis - results from repeated mild attacks of acute cholecystitis, which leads to thickening of the gallbladder wall.
EBV has an abnormal population of which kind of cell?
B cells
Intraabdominal infections (ex: periappendiceal fluid collection) are polymicrobial, with _______ being the most prominent organisms isolated.
B. fragilis and E. coli - S. aureus is a gram-positive organism that can cause abscess formation on the skin, but is not typically isolated from an intraabdominal abscess. - Although most infections within the abdominal cavity are polymicrobial, B. fragilis is a common anaerobic gram-negative bacillus that is frequently isolated, and of the choices given, it is the most likely organism to be identified in the culture of this patient's abscess. This organism expresses unique surface polysaccharides that have been shown to favor abscess formation. In addition to B. fragilis, common bacterial isolates from intraabdominal infections include other members of the normal colonic flora such as Escherichia coli, enterococci, and streptococci
Melanoma is caused by what mutations?
BRAF gene - proto-oncogene - normally triggers cell proliferation when activated by RAS protein V600E mutation of BRAF gene CDKN2A and RAS S-100 and HMB-45 positive
Patients with V600E mutation of BRAF in Melanoma can be treated with what?
BRAF inhibitors: Vemurafenib and Dabrafenib
_________ presents with fever and hemolytic anemia; predominantly in northeastern United States; asplenia = increased risk of severe disease
Babesiosis (Blood smear: ring form , "Maltese cross"; PCR)
What is transmitted by the Ixodes tick?
Babesiosis, Borrelia burgdorferi [lyme disease] and Anaplasma spp
________ is a benign capillary skin papules. Found in AIDS patients. Caused by Bartonella infections. Frequently mistaken for Kaposi sarcoma, but has neutrophilic infiltrate.
Bacillary Angiomatosis
Spores are resistant to chemical disinfectants, irradiation, desiccation, and temperatures as high as 120 C (248 F). _______ and _______ species commonly produce spores
Bacillus and Clostridium
_________ is a large, nonmotile, nonhemolytic, gram-positive rod that forms colonies in culture with multiple curled extensions at the edges that resemble a "Medusa head."
Bacillus anthracis - Initial manifestations of infection are nonspecific (eg, myalgia, fever, malaise), but proliferation of the bacteria in the mediastinum eventually causes hemorrhagic mediastinitis (often visible on chest x-ray as a widened mediastinum). - Subsequent dissemination through the bloodstream causes shock, brain edema/hemorrhage, and death. - Although pulmonary anthrax is quite rare, it can be seen in individuals who handle contaminated hides or animal hair ("woolsorter's disease") or those exposed to aerosolized biologic weapons (eg, opening contaminated mail).
________ causes cat-scratch disease, bacillary angiomatosis, and culture-negative endocarditis. Cat-scratch disease is characterized by low fever, lymphadenopathy, and a self-limited course.
Bartonella henselae
__________ is a gram-negative bacterium transmitted to humans during a cat scratch.
Bartonella henselae - Healthy individuals can subsequently develop cat-scratch disease (regional lymphadenopathy), but patients with advanced AIDS are at risk for the more serious clinical syndrome of bacillary angiomatosis (violaceous, highly vascular skin lesions with constitutional symptoms). - However, central nervous system manifestations are uncommon. - *contrast*: Toxoplasma gondii is an intracellular parasite that is typically transmitted to humans after accidental ingestion of contaminated cat feces (eg, cat handling, litter box).
- Reabsorption defect in thick ascending loop of Henle (affects Na+/K+/2Cl- cotransporter) - Metabolic alkalosis, hypokalemia, hypercalciuria
Bartter syndrome - Autosomal Recessive - Presents similarly to chronic Loop diuretic use
______ is a large yeast with thick walls and broad-based buds
Blastomyces - Blastomyces is a large yeast with thick walls and broad-based buds that disseminates primarily to the skin (not the reticuloendothelial system - Both Blastomyces and Coccidioides are dimorphic fungi that are inhaled into the lungs and replicate within macrophages. - Coccidioides immitis appears as large, thick-walled spherules containing endospores.
Examination of tissues or respiratory fluids with ________ infection shows round yeast with thick walls and broad-based budding.
Blastomyces dermatitidis
Ohio and Mississippi River valleys, Great Lakes region. Found in soil.
Blastomyces dermatitidis - clinical presentation: Pulmonary: pneumonia. Disseminated form is common and severe. - Lab dx: Culture (25ºC): branching hyphae. Biopsy: large, round yeasts with doubly refractile wall and single broad-based bud.
Is V/Q ratio higher at the apex or base of the lung? What about blood flow?
Blood flow is greatest at the base of the lung Ventilation and Perfusion are both higher at the base; but the V/Q ratio is higher at the APEX because there is decreased perfusion (less blood flow) [therefore, V/Q ratio is lowest at the base]
______ is characterized by generalized chromosomal instability. Increased susceptibility to neoplasms is present.
Bloom syndrome
_____ is characterized by a persistent pattern of unstable relationships, mood lability, and impulsivity. Individuals with this disorder may exhibit suicidal ideation or behavior in the context of an interpersonal crisis in which they feel rejected or abandoned.
Borderline personality disorder
In pulmonary embolism, is the PaO2 and PaCO2 low, high, or normal?
Both are low - usually, with other stuff, PaCO2 is normal (including other V/Q mismatches, and causes of normal A/a gradients [high altitudes, narcotics/respiratory depression, etc.]) *Side note*: -
Blunt chest trauma --> how to differentiate cardiac tamponade from hemothorax
Both have hypotension and tachycardia (ie, hypovolemic shock) as well as tachypnea due to the mass effect on the lung But, hemothorax will have FLAT jugular veins and absent basilar breath sounds
How to differentiate between thyrotoxicosis (ex: Graves disease) and exogenous source of thyroid hormone?
Both have suppressed TSH, with elevated T4 (free thyroxine); but in exogenous source, *thyroglobulin is undetectable [low levels = suppression of thyroid activity]*
______ vein obstruction causes symptoms similar to those seen in SVC syndrome, but only on one side of the body.
Brachiocephalic - The brachiocephalic vein drains the ipsilateral jugular and subclavian veins. The bilateral brachiocephalic veins combine to form the superior vena cava (SVC). - It is important to note that the right brachiocephalic vein also drains the right lymphatic duct, which drains lymph from the right upper extremity, the right face and neck, the right hemithorax, and the right upper quadrant of the abdomen.
- Solid, pale yellow-tan tumor that appears encapsulated. - "Coffee bean" nuclei on H&E stain.
Brenner tumor
Exposure to asbestos is much more likely to lead to ________ than ________
Bronchogenic Carcinoma (from bronchial epithelium) Mesothelioma (Pleura mesothelium; less likely although this is more specific for asbestos exposure)
Maturation of pro-B cells into pre-B cells with resulting expression of B cell-specific surface markers (eg, CD19, CD40) is dependent on signal transduction by ________ . A mutation in this gene causes __________ ,
Bruton tyrosine kinases X-linked agammaglobulinemia - characterized by hypogammaglobulinemia and recurrent infections after maternal IgG is depleted (~3 months of age). - Flow cytometry would show a marked decrease in CD19+ cells.
Segmental thrombosing vasculitis extending into nerves and veins
Buerger's Disease (vasculitis) - limited involvement of the vessel wall (eg, intact internal elastic lamina, no fibrinoid necrosis)
thromboangiitis obliterans is another name for
Buerger's disease
The presence of a pseudomembrane (exudate on colonic mucosa consisting of fibrin and inflammatory cells) in colonic mucosa is highly suggestive of ______ infection
C difficile [C. diff colitis] Risk factors - Recent antibiotics - Hospitalization - PPI Pathogenesis - Disruption of intestinal flora → C difficile overgrowth - Exotoxins cause mucosal injury - Pseudomembrane formation Clinical presentation - Profuse diarrhea (most common) -Fulminant colitis/toxic megacolon Diagnosis - PCR for toxin-encoding gene - EIA [EIA = enzyme immunoassay] for bacterial toxin or glutamate dehydrogenase Treatment - Oral vancomycin or fidaxomicin
Bronchoalveolar lavage fluid in *pulmonary sarcoidosis* demonstrates a *lymphocytic* predominance with a high _____ ratio.
CD4+/CD8+ (high number of CD4 T cells)
_____-related diabetes occurs after the progressive destruction of pancreatic islet cells leads to decreased insulin production.
CF
Deficiency of _______ can lead to repeated infections from *Neisseria* and Strep pneumonia [both have polysaccharide capsule]
C5-C9 (membrane attack complex) Killing of encapsulated organisms is done via alternative pathway, which largely depends on MAC
Pancreatic adenocarcinoma tumor marker
CA 19-9
Which anti-HTN drug causes gingival hyperplasia?
CCBs
Is RLQ pain more common among UC or CD?
CD - non-bloody diarrhea may be seen - creeping fat - strictures - B12 malabsorption - worse with smoking - associated with ASCA and Jews
What cells are involved in fighting off TB?
CD4 T cells and Macrophages (form granulomas) Mycobacteria tuberculosis primarily replicates within the phagosome, leading to display of mycobacterial antigens on major histocompatibility complex class II molecules. This results in the activation of CD4 cells and subsequent control of the infection with macrophages.
Sarcoidosis is a _______ mediated disease
CD4+ T-cell - , in which large numbers of CD4+ lymphocytes release interferon-gamma and tumor necrosis factor-alpha to drive macrophage activation and granuloma formation.
What trinucleotide repeat is associated with Fragile X syndrome?
CGG - Fragile X syndrome mainly affects males and is associated with CGG trinucleotide repeats on the X chromosome. - Features include intellectual disability; a long, narrow face; large protruding ears; macrocephaly; and macroorchidism.
Cardiac output, Preload, and afterload in *pregnancy* (increase/decrease/same)?
CO: Increase Preload: Increase Afterload: Decrease - Including decreased systemic vascular resistance and increased blood volume. These changes cause increased preload and decreased afterload, resulting in increased stroke volume and cardiac output. - Heart rate also gradually increases during pregnancy and is the major contributor to increased cardiac output in late pregnancy. - The driving force behind maternal hemodynamic changes is a significant decrease in systemic vascular resistance (SVR) due to both increased release of peripheral vasodilators (eg, nitric oxide, prostacyclin) and formation of a high-flow, low-resistance uteroplacental circuit (increases blood flow to the placenta and fetus). There is also significantly increased blood volume.
*Cardiogenic Shock:* CVP [R preload]: Increased PCWP [L preload]: Increased Cardiac Index (Cardiac/LV ouput): decreased SVR (afterload): increased SvO2: decreased
CVP [R preload]: Increased PCWP [L preload]: Increased Cardiac Index (Cardiac/LV ouput): decreased SVR (afterload): increased SvO2: decreased
______- sleep apnea is due to diminished respiratory drive from a neurologic disorder.
Central - It is usually associated with significant underlying chronic illness (eg, congestive heart failure, cerebrovascular disease, renal insufficiency) and is not more common in obesity.
*Obstructive:* CVP [R preload]: PCWP [L preload]: Cardiac Index (Cardiac/LV ouput): SVR (afterload): SvO2:
CVP [R preload]: Increased PCWP [L preload]: decreased ** Cardiac Index (Cardiac/LV ouput): decreased SVR (afterload): increased SvO2: decreased ** in tamponade, L preload is decreased, but PCWP is paradoxically increased due to external compression by pericardial fluid - ex: PE *Cardiac tamponade*: Cardiac tamponade involves increased pericardial pressure that restricts diastolic filling of the right-sided heart chambers, leading to obstructive shock with *increased central venous pressure and decreased stroke volume and cardiac output*. As tamponade progresses, diastolic pressures in all 4 cardiac chambers *increase and equalize with pericardial pressure (and with one another)[ex: increased LA pressure]*, stagnating blood flow within the heart. - In tamponade, the compressed right atrium is decreased in size, and elevated right atrial pressures are transmitted backward to the vena cava, causing increased central venous pressure. With decreased right-sided filling, less blood is pumped through the pulmonary circulation to the left atrium and left ventricle, resulting in decreased stroke volume and cardiac output (and causing hypotension and shock). Although the volume of blood reaching the left atrium is reduced, left atrial pressure is increased due to external compression by the excessive pericardial fluid
*Hypovolemic Shock:* CVP [R preload]: PCWP [L preload]: Cardiac Index (Cardiac/LV ouput): SVR (afterload): SvO2:
CVP [R preload]: decreased PCWP [L preload]: decreased Cardiac Index (Cardiac/LV ouput): decreased SVR (afterload): increased SvO2: decreased - ex: GI bleeding
*Distributive:* CVP [R preload]: PCWP [L preload]: Cardiac Index (Cardiac/LV ouput): SVR (afterload): SvO2:
CVP [R preload]: decreased PCWP [L preload]: decreased Cardiac Index (Cardiac/LV ouput): increased ** SVR (afterload): decreased SvO2: increased ** **Cardiac index and SvO2 are usually decreased in *neurogenic shock* due to impaired sympathetic reflexes - *Septic shock* is a type of distributive shock
*Serum studies in Osteomalacia* Ca: Phosph: Alkaline Phosphatase: PTH:
Ca: low Phosph: low Alkaline Phosphatase: high PTH: high *contrast: Paget = normal Ca, PO, and PTH , but elevated Alkaline Phosphatase*
______ is released by the parafollicular cells of the thyroid. It inhibits osteoclast activity, leading to decreased (not increased) bone resorption.
Calcitonin - Calcitonin is regulated primarily by circulating calcium levels
What markers are ⊕ in almost all mesotheliomas?
Calretinin Cytokeratin 5/6 [negative in most cancers]
_________ presents as deep, painful ulcers with ragged borders that are associated with a grey exudate and inguinal lymphadenopathy.
Chancroid, due to Haemophilus ducreyi - painful --> you "do cry" with H ducreyi - On Gram stain, the organism appears as curved, gram-negative rods, often in a clumping pattern. - The disease is relatively uncommon in the United States but has much higher prevalence in sub-Saharan Africa, Latin America, and regions of Asia. - Don't confuse with chancre from syphilis
Which esophagitis has the following endoscopic findings: Patches of adherent, gray/white pseudomembranes on erythematous mucosa
Candida albicans Microscopic findings: Yeast cells & pseudohyphae invading mucosal cells
CD4 count < 500
Candidiasis (thrush) Kaposi Sarcoma (HHV-8) [biopsy with lymphocytic infiltration] Oral hairy leukoplakia (unscrapable white plaque on lateral tongue) Squamous cell carcinoma, commonly of anus (men who have sex with men) or cervix
_______ is an arrangement in which a payor pays a fixed, predetermined fee to provide all the services required by a patient. Payors may negotiate a capitated contract with an insurance company that then pays the providers, or a large medical group may negotiate directly with the payor.
Capitation ex: the employer would like to negotiate a contract in which the medical group would provide care to all the company's employees in exchange for a set monthly fee per employee.
- flushing, diarrhea, bronchospasm [wheezing] - Increased 5-HIAA (serotonin metabolite) in urine - Pulmonic/tricuspid valve disease (R side of heart) - Pellegra - telangiectasia
Carcinoid tumor - carcinoid syndrome once metastasize to liver/lung (because they metabolize/inactivate serotonin) - only R side of heart effected (not left side) - excess tryptophan converted to serotonin --> tryptophan deficiency --> niacin deficiency --> pallegra
_____ are neuroendocrine malignancies that appear histologically as sheets of uniform cells with dense core granules noted on electron microscopy.
Carcinoid tumors - They sometimes cause carcinoid syndrome (eg, flushing, diarrhea, wheezing), which is seen more commonly with gastrointestinal tumors. - However, they tend to involve the large bronchi; fibrosis and pleural plaques are unexpected.
_______ typically results in neck and/or arm pain associated with neurologic deficits that follow a dermatomal/myotomal pattern. *Osteophytes* that form due to _______ can progressively narrow the neural foramina leading to nerve root compression.
Cervical radiculopathy degenerative changes in the vertebral joints - Radiculopathies occur due to compression of spinal nerve roots, which is most commonly due to either: -- Spinal spondylosis: Aging leads to degeneration of the vertebral bodies, discs, and joints. Disc space decreases, and joint stress results in osteophyte (eg, bone spur) formation, which slowly narrows the neural foramina and leads to a subacute onset of symptoms (as seen in this patient). -- Vertebral disc herniation: Degeneration of ligamentous fibers can lead to a tear in the intervertebral disc annulus, resulting in herniation of the nucleus pulposus with potential nerve root compression. Disc rupture typically occurs acutely (eg, during weight lifting).
What enzymes are anti-oxidants?
Catalase Superoxide dismutase Glutathione peroxidase
*Acute hepatitis* has what effect on the liver?
Causes *hepatocyte ballooning [swelling]* degeneration and apoptosis with mononuclear cell infiltration. - the hallmark histologic findings of acute viral hepatitis include hepatocyte necrosis and apoptosis with mononuclear infiltration. Hepatocyte necrosis is characterized by cellular swelling and cytoplasmic emptying (eg, "ballooning degeneration") likely caused by ATP depletion and disruption of the intermediate filament network. In severe cases, regions of adjacent lobules are interconnected by swaths of dead hepatocytes called "bridging necrosis." - Hepatocyte apoptosis is characterized by cellular shrinkage and nuclear fragmentation with intense eosinophilia (eg, Councilman bodies) and is likely caused by mitochondrial oxidative damage. The presence of virally infected and dying hepatocytes promotes mononuclear inflammation in the sinusoids and portal tracts. - Nodular regeneration of hepatocytes is generally found in patients with cirrhosis due to chronic hepatitis. HAV does not cause chronic hepatitis, but HBV and HCV are associated with chronic hepatitis that can result in cirrhosis.
________ is due to mutation of the genes responsible for myelin synthesis. Affected patients frequently present with distal muscle weakness, sensory loss, and atrophy of the calf muscles (producing the characteristic stork leg deformity).
Charcot-Marie-Tooth disease
_______ are small, red, cutaneous papules common in aging adults.
Cherry hemangiomas - They do not regress spontaneously and typically increase in number with age. - Light microscopy of these lesions shows proliferation of capillaries and post-capillary venules in the papillary dermis.
- congenital disorders - underdevelopment of the posterior fossa --> cerebellum and medulla herniate through the foramen magnum
Chiari malformations - Chiari type I is relatively benign and presents during adulthood with occipital headache and cerebellar dysfunction. - Chiari type II is a more severe form that affects neonates and is often associated with lumbar myelomeningocele and hydrocephalus.
Craniopharyngioma
Children 10-14 yo Supracellar - these tumors occur anywhere from *pituitary gland to base of 3rd ventricle* Benign; symptoms from compression effects: - visual field defects - hormonal imbalance - behavioral changes (frontal lobe disfunction) - Can compress optic chiasm --> *bitemporal hemianopsia* Derived from *Rathkes pouch* - invagination of ectoderm - protrudes from roof of mouth - also forms Anterior pituitary May contain epithelial cells --> appearance similar to *pulp of developing teeth*
Inclusion conjunctivitis is seen with ________ infection of the newborn.
Chlamydia trachomatis
- Often clinically silent until advanced - Nausea, weight loss, RUQ pain - Jaundice, hepatomegaly, ± palpable gallbladder (Courvoisier sign) Imaging: - *dilated bile ducts in the absence of an obstructive gallstone* Labs: - Cholestatic pattern of liver injury (↑↑ alkaline phosphatase, hyperbilirubinemia)
Cholangiocarcinoma
Clonarchis senensis (liver fluke) is associated with which carcinoma?
Cholangiocarcinoma
Histology *Biopsy*: - *Adenocarcinoma* with cuboidal or columnar cells with prominent nucleoli arranged in glandular structures - + Mucin production, + desmoplasmic response
Cholangiocarcinoma
_______ is a malignancy of the bile duct epithelium that eventually obstructs biliary drainage, resulting in cholestasis (elevated alkaline phosphatase, hyperbilirubinemia) with jaundice, weight loss, pain in the right upper quadrant, and hepatomegaly.
Cholangiocarcinoma
________ are congenital dilations of the common bile duct that typically present during childhood (age <10) with recurrent abdominal pain and jaundice.
Choledochal cysts
_______ are characterized by neoplastic chondrocytes in a hyaline cartilage matrix, usually with small calcifications.
Chondrosarcomas
Hep Serologic Status: HBsAg, HBeAg, Anti-HBc IgG
Chronic Infection - Anti-HBsAg immunoglobulin G (IgG) appears after either successful HBV vaccination or HBsAg clearance and remains detectable for life (indicator of non-infectivity and immunity). Because this patient is symptomatic, he obviously has not cleared the virus and would likely not yet have anti-HBsAg IgG
_______ disease should be suspected in a child with recurrent infections by catalase-positive organisms (eg, Staphylococcus aureus, Aspergillus) who has normal immunoglobulins and no leukopenia.
Chronic granulomatous disease - Pathogenesis involves the defective intracellular killing of phagocytized organisms within neutrophils due to an impaired respiratory burst. - *NADPH oxidase deficiency*
Amyloid A (AA) is associated with which disease conditions
Chronic infection/inflammation
________ usually causes hyperphosphatemia (binds serum Ca2+) and low 1,25-dihydroxyvitamin D (decreases intestinal Ca2+ absorption and Ca2+ release from bone). The resulting hypocalcemia stimulates release of parathyroid hormone, causing secondary hyperparathyroidism.
Chronic kidney disease - In the physiologic state, parathyroid hormone (PTH) causes an overall increase in serum calcium (Ca2+) and a decrease serum phosphate (PO4) via the following effects: - Increasing osteoclastic bone resorption, releasing Ca2+ and PO4 into serum - Increasing renal calcium reabsorption and reducing phosphate reabsorption - Increasing formation of 1,25-dihydroxycholecalciferol (by upregulating renal 1-alpha-hydroxylase), which increases intestinal Ca2+ and PO4 absorption
- increased breath sounds - increased tactile fremitus - dullness to percussion
Consolidation
Postprandial epigastric pain and associated food aversion/weight loss in the setting of generalized atherosclerosis (eg, coronary and carotid artery disease) is consistent with ___________ .
Chronic mesenteric ischemia - When atherosclerosis involves the mesenteric arteries, the bowel can suffer from diminished blood supply. Intestinal hypoperfusion, which can be very painful, is especially pronounced within an hour after meals when more blood is needed for the digestion/absorption of nutrients (intestinal angina). - This is analogous to stable cardiac angina, chest pain that occurs with physical exertion due to increased myocardial oxygen demand. - The diagnosis can be made with duplex ultrasonography or angiography showing high-grade stenosis in the celiac and mesenteric arteries.
Diarrhea, weight loss, and epigastric calcifications in a patient with chronic alcohol use suggests
Chronic pancreatitis with resulting *pancreatic exocrine insufficiency and malabsorption*
Transplant Rxn: - Inflammation and *fibrosis*, esp. vessels - Kidneys: fibrosis of capillaries, glomeruli - Heart: narrowing of coronary arteries - Lungs: bronchiolitis obliterans (injury to small airways) - *Involves cell-mediated and humoral systems*
Chronic rejection - months to years after transplant
- Asthma, rhinosinositis - Eosinophils - P-ANCA (Anti-Myeloperoxidase Antibodies) - Possible wrist/foot drop, etc.
Churg-Strauss (Eosinophilic Granulomatosis with Polyangitis)
Ciliated cells are seen how far distally in the respiratory tree?
Ciliated cells continue to be present through the proximal portions of the respiratory bronchioles, but are not present in the alveolar ducts or in the alveoli themselves. This arrangement is important because cilia function to propel mucus toward the pharynx. The presence of cilia beyond the most distal mucus-producing cells (goblet cells end before the terminal bronchioles) prevents bronchiolar mucus accumulation and airflow obstruction. - The rings of hyaline cartilage that encircle the trachea are replaced by cartilaginous plates in the bronchi. These rings and plates help keep the larger airways open and end at the termination of the smallest bronchi (they are not found in bronchioles). - Goblet cells are mucus-secreting cells that are present from the trachea down to the larger bronchioles. They are not found within the terminal bronchioles, which are lined by club cells. - The submucosal mucous glands and serous glands are found from the trachea to the distal-most bronchi and produce mucinous components that help trap inhaled particles. They are not present within the bronchioles.
_________ is a phosphodiesterase inhibitor that inhibits platelet aggregation and acts as a direct arterial vasodilator.
Cilostazol - The net effect is a decrease in claudication symptoms and an increase in pain-free walking distances in patients with peripheral arterial disease (PAD).
What part of the Ig do macrophages bind to?
Constant heavy 2 and 3
What part of the Ig does complement bind to?
Constant heavy chain 2
Anemia of chronic disease Circulating iron levels, bone marrow iron levels, and TIBC?
Circulating iron: Low Bone marrow iron: high TIBC: Low [contrast with IDA] - ACD is primarily mediated by hepcidin, a small peptide released by the liver in response to inflammation. Hepcidin binds to and inactivates iron channels (ferroportin) on enterocytes and reticuloendothelial macrophages, leading to reduced iron absorption in the gut and reduced iron recycling by the reticuloendothelial system (the site of senescent erythrocyte destruction and the source of >95% of daily iron for new RBC production). - These changes significantly reduce circulating iron levels, which impairs the generation of heme for new erythrocytes. Although patients with suspected ACD do not generally require bone marrow biopsy for diagnosis, it would show increased sequestration of iron within macrophages and reduced quantities of erythrocyte precursor cells (eg, normoblasts, reticulocytes). - Patients with ACD typically develop a normocytic (or slightly microcytic) anemia with low reticulocyte count. Treatment of the underlying inflammatory condition (eg, methotrexate for RA) reduces serum inflammatory cytokine levels and generally improves the anemia.
_______ irreversibly blocks the P2Y12 component of ADP* receptors on the platelet surface and prevents platelet aggregation.
Clopidogrel, Ticlopidine, Ticagrelor - Clopidogrel, etc. is as effective as aspirin in the prevention of cardiovascular events in patients with coronary heart disease. - Contraindication: Omeprazole (also a CYP2C19 inhibitor)
Actin depolymerization is mediated by __(organism + toxin)___ , which primarily causes infectious diarrhea.
Clostridioides (formerly Clostridium) difficile cytotoxin B
Pseudomembranes composed of fibrin and inflammatory debris are seen with
Clostridium difficile infection - associated with Abx use - complication: toxic megacolon (like UC)
Rapidly progressive pain, swelling, and gas/necrosis at the site of a penetrating foot injury, raising strong suspicion for ______ infection.
Clostridium perfringens - C perfringens is an obligate anaerobic, spore-forming, gram-positive rod found in soil. Most cases develop following the introduction of spores into tissue during penetrating injury (eg, knife wound, puncture wound); significant vascular damage is generally required to create the anaerobic environment necessary for vegetative bacterial proliferation. - C perfringens classically causes gas gangrene (eg, necrosis, gas in tissue) within hours of infection. This is primarily mediated by the generation of alpha toxin (lecithinase), a potent phospholipase C mimetic that splits host phospholipids. This compound hydrolyzes lecithin-containing lipoprotein complexes in cell membranes, which causes cell lysis, tissue necrosis, and edema. It also mediates intravascular aggregations of platelets, neutrophils, and fibrin, which results in vascular occlusion and further promotes the anaerobic environment required for bacterial proliferation. - Although C perfringens produces a vast array of other cytotoxins, alpha toxin is thought to mediate its most devastating effects. - C perfringens uses carbohydrates for energy; its rapid metabolism of muscle tissue carbohydrates produces significant amounts of gas, which can be seen on plain radiographs or CT scan.
_____ are located at the bronchoalveolar alveolar junction and protect and repair the distal airway (terminal bronchioles).
Club cells (bronchiolar cells)
_____ appears as large, thick-walled spherules containing endospores.
Coccidioides immitis - Both Blastomyces and Coccidioides are dimorphic fungi that are inhaled into the lungs and replicate within macrophages. - However, Blastomyces is a large yeast with thick walls and broad-based buds that disseminates primarily to the skin (not the reticuloendothelial system)
Southwestern states (desert areas). Mold form is present in soil.
Coccidioides immitis - clinical presentation: Pulmonary form: flu-like illness, cough, erythema nodosum. Disseminated form: affects skin, bones, and lungs. - Lab dx: Culture (25ºC): forms hyphae. Biopsy: at 37º forms thick-walled spherules filled with endospores.
Most *hepatic* neoplasms are due to metastatic disease from a distant site. _________ is the most common cause of hepatic metastases due to direct blood flow from the colon (and superior rectum) to the liver via the _______ .
Colorectal cancer portal venous circulation
_______ are benign proliferations of melanocytes that involve both the dermis and epidermis. The lesions appear as slightly raised papules with uniform pigmentation and symmetrical sharp borders.
Compound nevi
______ is tested by asking the patient to follow a multistep command.
Comprehension - This usually involves relatively brief tasks such as taking a piece of paper from the examiner, folding it in half, and placing it on the floor. Due to the brevity of these actions, attention and concentration may not be tested effectively.
Vesicoureteral Reflux (VUR)
Congenital malformation in which the ureter enters the bladder at an abnormal angle, predisposing the patient to chronic pyelonephritis --> renal scarring --> - loss of nephrons and secondary *HTN* - renal scarring (most commonly at the upper and lower poles of kidney [where compound papillae are formed])
_______ is typically noted by 2 to 4 weeks of age, after which the child prefers to hold the head tilted to one side. It is most commonly the result of _______ in utero or birth trauma. A soft-tissue mass may be palpable in the inferior one-third of the affected SCM.
Congenital torticollis malposition of the head - Most cases resolve with conservative therapy and stretching exercises. - *It is most commonly caused by birth trauma (eg, breech delivery) or malposition of the head in utero (eg, due to fetal macrosomia or oligohydramnios), both of which can result in sternocleidomastoid muscle (SCM) injury and fibrosis.* - Children with congenital torticollis may have additional musculoskeletal anomalies, including hip dysplasia, metatarsus adductus (ie, adduction of the forefoot), and talipes equinovarus (ie, clubfoot).
Neonate with retinal lesions (chorioretinitis) and hydrocephalus has a placenta containing inflammatory cells, calcifications, and crescent-shaped organisms. These findings are consistent with _______
Congenital toxoplasmosis, an infection caused by the intracellular parasite Toxoplasma gondii - Can also be transmitted from oocysts from cat fecies - diffuse intracranial calcifications are the classic finding on imaging.
______ is a form of one-way DNA transfer performed by bacteria carrying a plasmid with the fertility (F) factor.
Conjugation - The process begins with the donating bacterium producing a sex pilus, which then forms a direct connection with the receiving bacterium. Next, the donating bacterium transfers a single DNA strand containing the F factor to the recipient organism, after which, complementary DNA strands are synthesized.
The zona fasciculata secretes what hormone(s)?
Cortisol (glucocorticoids)
Intracellular polyphosphate granules are characteristic of ___________ ; they can be visualized on microscopy after growing the pathogen on Loeffler medium and staining it with methylene blue.
Corynebacterium diphtheriae
Gram positive rods in blood culture
Corynebacterium species (diphtheroid) Clostridium species Nocardia species or the anaerobic Actinomyces species Listeria species
Abdominal pain (RLQ) + Diarrhea (possibly bloody if colon is involved) =
Crohn's disease - Crohn disease typically presents with prolonged diarrhea and abdominal pain. Diarrhea can be bloody if the colon is involved. - Constitutional symptoms (eg, low-grade fever, fatigue), malabsorption, and weight loss are also common. - Complications include strictures (due to bowel wall edema, fibrosis, and thickening* of the muscularis mucosae), fistulas (due to penetration of ulcers through the intestinal wall), and abscesses. - Transmural inflammation of the bowel wall may result in the formation of fistulas and fibrotic strictures, causing bowel obstruction. Fistulas can form between 2 adjacent loops of bowel (enteroenteric fistula), between the bowel and another organ (eg, bladder, vagina), or between the bowel and skin of the abdominal wall (enterocutaneous fistula). Perianal fistulas and abscesses are also often seen.
_________ Grows well in decaying wood/soil (especially soil enriched by bird droppings [birds are not vectors])
Cryptococcus neoformans (found all over US) - most cases associated with severe immunosuppression
_______ is a large yeast with a thick polysaccharide capsule. It can replicate within macrophages and cause pulmonary infection in patients with advanced AIDS.
Cryptococcus neoformans - Dissemination usually leads to meningoencephalitis (eg, slowly worsening headache, confusion, neurologic symptoms)
Colon biopsy findings (not colonoscopy): Basophilic clusters seen on the surface of intestinal mucosal cells
Cryptosporidium
_______ is a common cause of self-limited diarrhea in immunocompetent hosts, but may cause life-threatening diarrhea in immunocompromised patients (eg, advanced AIDS). Diagnosis may be made by visualizing oocysts with *modified acid-fast stain* in stool or basophilic organisms lining the brush-border in a biopsy.
Cryptosporidium
Recurrent nephrolithiasis in a young patient should raise suspicion for what?
Cystinuria (Aminoaciduria) - *Hexagonal* shaped crystals - Cystinuria = AR disorder - The sodium cyanide-nitroprusside test = detects the presence of urinary cystine. - Transporter defect also results in poor reabsorption of Cysteine, Ornithine, Lysine, Arginine (COLA) - treat with hydration and urinary alkalinization (acetylzolamide)
______ is a commonly used immunohistochemical marker of epithelial cell carcinomas (ex: Squamous cell carcinoma)
Cytokeratin
Cellular Receptor: Cellular integrins Virus: ????
Cytomegalovirus
_________ is the most common viral opportunistic infection of the gastrointestinal tract in patients with advanced AIDS
Cytomegalovirus (CMV) (HHV-5) - As with all members of the herpesvirus family, latent infection is established after resolution of the initial infection. Reactivation can occur at any time but is most common in the setting of immunosuppression. - Patients with CMV colitis have fever, anorexia, weight loss, and abdominal pain. The pain may be vague initially but becomes more localized as the disease progresses. - Colonoscopy usually shows erythema, erosions, and ulcerations; colonic biopsy typically reveals large cells with prominent basophilic intranuclear inclusions. - Histologic examination of biopsy specimens will reveal acute and chronic inflammatory changes, vasculitis, and large cells with large, ovoid nuclei containing centralized intranuclear basophilic inclusions (owl's eye appearance).
Ganciclovir is used in the treatment of
Cytomegalovirus (CMV) infection. - This medication inhibits viral synthesis by blocking CMV DNA polymerase. However, ganciclovir also blocks host DNA polymerase to a lesser degree, which can lead to hematologic side effects such as neutropenia*, anemia, and thrombocytopenia. - CMV primarily causes symptomatic disease (eg, retinitis, esophagitis, pneumonia) in the immunosuppressed. - Characteristic manifestations of central nervous system involvement include polyneuropathy, transverse myelitis, and encephalitis.
______ is particularly common in patients with lung transplants (typically occurring within the first few months after transplant). Most but not all transplant centers practice universal prophylaxis for lung transplant recipients (eg, __(treatment)___).
Cytomegalovirus (CMV) pneumonitis Valganciclovir - CMV is an enveloped double-stranded DNA virus belonging to the Herpesviridae family. - Major risk groups for infections include transplant patients, patients with HIV, and fetuses (congenital infections). - CMV pneumonitis is the most common form of tissue-invasive CMV following lung transplantation; other organ-specific disease manifestions (eg, esophagitis, colitis, and retinitis) occur more frequently in patients with HIV. - Biopsy findings consistent with CMV include enlarged cells with intranuclear and intracytoplasmic inclusions (viral particles); there is often a surrounding halo (owl's eye).
________ can occur in transplant patients and usually presents with odynophagia or dysphagia that can be accompanied by fever or burning chest pain. Endoscopy typically shows *linear and shallow ulcerations* in the lower esophagus, and histology usually shows enlarged cells with intranuclear inclusions.
Cytomegalovirus esophagitis - HSV = punched out ulcers
Classic endoscopic findings for ______ include stacked, circular, ringlike indentations; linear furrowing; and scattered, small, whitish papules
Eosinophilic esophagitis - Scattered, small whitish papules = eosinophilic microabscesses
_______ is an inherited disorder of proximal tubular transport. Glucose, bicarbonate, calcium, phosphate, and amino acids are lost, leading to a number of metabolic abnormalities.
Fanconi syndrome
Homeobox genes encode _______ that play an important role in the segmental organization of the embryo along the cranio-caudal axis.
DNA-binding transcription factors - A homeobox is a highly conserved DNA sequence that is usually about 180 nucleotides in length. A gene containing a homeobox sequence is called a homeobox or hox gene. These genes typically code for transcription factors that bind to regulatory regions on DNA, altering the expression of genes involved in the segmental organization of the embryo. - Proper morphogenesis ensures that tissues, organs, and structural elements of the body are formed in the correct position along the cranio-caudal axis. Homeobox gene mutations interrupt this developmental process, often resulting in severe abnormalities such as skeletal malformations and improperly positioned limbs and appendages.
- Agenesis of cerebellar vermis --> cystic enlargement of 4th ventricle that fills the enlarged posterior fossa. - Associated with noncommunicating hydrocephalus, spina bifida.
Dandy-Walker syndrome
_______ is ethically appropriate when only one treatment option is medically reasonable and has clearly superior evidence-based support. Patients with complete placenta previa should be counseled that cesarean delivery is medically necessary.
Directive counseling
Symptoms of Endometriosis
Dysmenorrhea Dyspareunia - painful intercourse - ectopic tissue near vagina *Infertility* - ovarian/fallopian tube lesion Dyschezia - painful defecation - ectopic tissue near rectum Dysuria - painful urination - ectopic tissue near bladder
Age-related changes to the respiratory system include
Decreased chest wall compliance - Calcification of the intercostal joints and tendon insertion sites, as well as degeneration of the spine (eg, kyphosis), reduces chest wall expansion and limits the potential increase in tidal volume. Decreased alveolar elastic recoil with resulting alveolar enlargement and air trapping - Degeneration of elastin causes increased alveolar compliance with alveolar enlargement and increased air trapping. This increases residual volume and decreases forced vital capacity, further limiting the achievable increase in tidal volume - The alveolar enlargement increases ventilation-perfusion mismatch and decreases the efficiency of O2 exchange in 2 ways. First, it decreases the percentage of alveolar surface area in contact with alveolar capillaries, effectively increasing dead space. Second, the increased air trapping decreases ventilation of highly perfused alveoli at the base of the lungs. -- These changes limit the potential increase in tidal volume and also increase the alveolar-arterial O2 gradient (ie, decrease the efficiency of alveolar-capillary gas exchange), reducing the ability to compensate for hypoxemia.
Effect of chronic glucocorticoid therapy on hormones:
Decreases CRH and ACTH --> decreased cortisol - Glucocorticoids suppress the synthesis and release of corticotropin-releasing hormone (CRH) from the hypothalamus and also block its ACTH stimulatory effect on the anterior pituitary. - Long-term suppression leads to atrophy of hypothalamic CRH-releasing neurons, pituitary corticotrophic cells, and the adrenal zona reticularis (androgen- producing inner zone) and zona fasciculata (cortisol-producing middle zone). - Chronic glucocorticoid use is characterized by low CRH, ACTH, and cortisol levels that cannot rise in response to stressful situations (eg, infections, surgery). - This lack of a stress response can result in relative glucocorticoid deficiency even when the patient's baseline glucocorticoid regimen is maintained. Because glucocorticoids help maintain normal vascular tone (eg, by increasing norepinephrine, renin, and angiotensin vasoconstrictive activity), glucocorticoid deficiency can precipitate hypotension/shock. - In such cases, a higher stress dose is needed to compensate for the increased physiologic demands and prevent the development of adrenal crisis. - *Contrast with high cortisol but low CRH and ACTH*: Excessive cortisol production from an autonomous *adrenal adenoma* suppresses CRH and ACTH production by the hypothalamus and pituitary, respectively.
Is Bernard-Soulier syndrome due to a defect in aggregation or adhesion?
Defect in adhesion. Decreased GpIb --> decreased platelet-to-vWF adhesion. Labs: abnormal ristocetin test, large platelets.
Is Glanzmann Thrombasthenia due to a defect in aggregation or adhesion?
Defect in aggregation. Decreased GpIIb/IIIa (Decreased integrin αIIbβ3) --> decreased platelet-to-platelet aggregation and defective platelet plug formation. Labs: blood smear shows no platelet clumping.
What clinical syndrome is expected based on this location of lacunar infarct: Genu/anterior limb of the internal capsule and/or Basilar Pons
Dysarthria-clumsy hand syndrome (ie, dysarthria and dysphagia with clumsiness of one hand)
________ is indicated for the treatment of Loa loa (loiasis) and Wuchereria bancrofti (lymphatic filariasis) infections.
Diethylcarbamazine
Microscopically, __________ is visible as widespread axonal swelling, most pronounced at the gray-white matter junction, with accumulation of transport proteins (eg, amyloid precursor, alpha-synuclein) at the site of injury.
Diffuse Axonal Swelling
________ is a type of traumatic brain injury that results from disruption of the white matter tracts.
Diffuse axonal injury (DAI)
________ slows AV nodal conduction speed by augmenting vagal parasympathetic tone and increases cardiac contractility by inhibiting Na+/K+-ATPase (increases intracellular calcium). It also decreases the APD and can cause QT interval shortening.
Digoxin
_________ slows conduction through the AV node via increased parasympathetic (vagal) tone
Digoxin - also inhibits Na/K ATPase pump - Digoxin increases ventricular contractility (positive inotropy) by inhibiting the sodium-potassium ATPase pump to increase intracellular sodium and consequently increase intracellular calcium. This effect can improve cardiac output and symptoms (eg, dyspnea, orthopnea) in patients with left ventricular systolic dysfunction, but it does not contribute to improved rate control.
- Most common in adolescents - Equivalent to male seminoma but rarer. - Sheets of uniform "fried egg" cells - Tumor markers: increased hCG, LDH.
Dysgerminoma - germ cell tumor
In ________ , patients develop abdominal pain (usually in the left lower quadrant), fever, nausea and vomiting, and alterations in bowel habits (eg, diarrhea, constipation).
Diverticulitis - Diverticulosis: gross pathology demonstrates multiple sac-like outpouchings from the sigmoid colon, which is consistent with diverticulosis. Diverticulosis occurs due to excessive colonic contractions that cause increased intraluminal pressure; this forces the mucosa and submucosa to herniate through the muscularis at naturally weak areas where the vasa recta penetrate.
- LLQ pain - Fever - Leukocytosis (elevated WBC)
Diverticulitis - Inflammation of diverticula with wall thickening - Pathogenesis: trapped food particles & ↑ intracolonic pressure that cause microperforation of colonic diverticula - Dx: Abdominal CT (oral or IV contrast) - Treatment: Abx Complications: - abscess, - fistula (colovesical fistula --> pneumaturia) - obstruction (inflammatory stenosis) - perforation (--> peritonitis). Diverticulitis is characterized by inflammation of colonic diverticula. Patients have abdominal pain, nausea, vomiting, and changes in bowel habits. Low-grade fever and leukocytosis are common, and physical examination may demonstrate a tender mass in the left lower quadrant.
- Age > 60 yo - Obesity - Diets low in fiber, high in total fat/red meat. - Often asymptomatic or associated with vague discomfort. - Complications include diverticular bleeding (painless hematochezia), etc.
Diverticulosis - other complications: diverticulitis - Many false diverticula of the colon, commonly sigmoid. - Common (in ~ 50% of people > 60 years). - Caused by increased intraluminal pressure and focal weakness in colonic wall. - False diverticula occur when the mucosa and submucosa herniate through areas of focal weakness in the muscularis. - Exaggerated contractions of colonic smooth muscle segments are responsible for colonic diverticulosis; the resultant increased intraluminal pressure causes herniation and false diverticula formation.
________ is a beta adrenergic agonist with predominant activity on beta-1 receptors. It causes an increase in heart rate and cardiac contractility, leading to an increase in myocardial oxygen consumption.
Dobutamine - used for management of refractory heart failure associated with severe left ventricular systolic dysfunction and cardiogenic shock. - Stimulation of beta adrenergic receptors results in increased production of cAMP in target cells
Duodenal atresia is associated with:
Down Syndrome and Polyhydramnios [double bubble sign]
Hirschsprung is associated with
Down syndrome
A complete atrioventricular (AV) canal defect is comprised of an atrial septal defect, a ventricular septal defect, and a common AV valve. It is the most common congenital cardiac anomaly associated with ________
Down syndrome - Failure of endocardial cushion fusion results in an ostium primum atrial septal defect; a ventricular septal defect; and a single AV valve. Significant left-to-right shunting and AV valve regurgitation lead to excessive pulmonary blood flow and symptoms of heart failure (eg, tachypnea, poor feeding). Auscultatory findings of AV valve regurgitation (holosystolic, best heard at apex) and increased pulmonary venous return (mid-diastolic rumble) are characteristic.
______ is effective against lyme disease/many tick born illnesses
Doxycycline
What drugs are PCSK9 inhibitors and what is their MOA?
Drugs: - Alirocumab - Evolocumab MOA: - Monoclonal Abs that bind to PCSK9 --> Stop LDL-receptor degradation --> increase LDL removal from bloodstream - high risk patients who have high LDL despite statin therapy AE: - Myalgias, delirium, dementia, other neurocognitive effects
Often seen early as microcalcifications on mammography.
Ductal carcinoma in situ
What organ secretes motilin?
Duodenal mucosa
______ , deleted in DMD/BMD, is a structural component of skeletal muscle fibers that provides mechanical stability to the sarcolemma, and it links a component of the cytoskeleton (actin) to transmembrane proteins (α- and β-dystrophiglycans) that are connected to the extracellular matrix.
Dystrophin - Maintains muscle membranes -Connects intracellular actin to transmembrane proteins - Binds alpha and beta-dystroglycan in membrane - Connected to the extracellular matrix (laminin) - Also found in cardiac and smooth muscle -> Many patients with muscular dystrophy develop heart failure and cardiac complications
Oncogenesis from HPV strains (eg, 16, 18) is attributed to viral proteins; ____ degrades p53 (tumor suppressor protein regulating the cell cycle) and ______ inhibits the retinoblastoma gene product Rb.
E6 E7 - Smoking increases the likelihood of an HPV infection developing into intraepithelial neoplasia and cancer.
Cellular Receptor: CR2 (CD21) Virus: ????
EBV
_________ are antifungal medications that inhibit synthesis of the polysaccharide glucan (1,3-beta-D-glucan), an essential component of the fungal cell wall.
Echinocandins (eg, caspofungin, micafungin) - Inhibit fungal cell wall synthesis (unique) - Most active against Candida species and Aspergillus. - It is not active against Cryptococcus neoformans and has limited activity against Mucor and Rhizopus species.
- Hydatid cyst ("egg calcification") in liver; - cyst rupture can cause anaphylaxis
Echinococcus granulosus
Ingestion of eggs in food contaminated with *dog feces* *Sheep* are intermediate hosts
Echinococcus granulosus
Dx Cushing Syndrome: - ACTH: Normal/Elevated - High Dose Dexamethasone Test: ACTH and Cortisol levels unchanged
Ectopic ACTH production (ex: small cell carcinoma of lung) Excess ACTH secretion causes identifiable clinical findings: - Hyperpigmentation: Both ACTH and alpha-melanocyte-stimulating hormone (MSH) are derived from pro-opiomelanocortin, leading to cosecretion of alpha-MSH. ACTH also directly stimulates the MC2R receptor on melanocytes. - Androgenization: ACTH stimulates production of adrenal androgens (eg, ↑DHEAS [dehydroepiandrosterone sulfate], androstenedione). This leads to hirsutism, menstrual abnormalities, and oily skin.
Hyperplastic growth of endometrial glands and stroma
Endometrial polyp - *common near menopause* - may cause *painless* uterine bleeding - due to unopposed estrogen production (chronic anovulation --> lack of progesterone) - treatment: Tamoxifen (may cause endometrial cancer)
- Inflammation of endometrium - associated with retained products of conception following delivery, miscarriage, abortion, or with foreign body (eg, IUD). - Retained material is nidus for bacteria from vagina or GI tract.
Endometritis - Chronic endometritis shows plasma cells on histology. - Treatment: gentamicin + clindamycin +/− ampicillin.
Female Reproductive organ biopsy hallmark: plasma cells
Endometritis - plasma cells indicate chronic inflammation
Bosentan
Endothelin Receptor antagonists: - Competitively antagonizes endothelin-1 receptors --> decreased pulmonary vascular resistance. - Hepatotoxic (monitor LFTs). Endothelin-1 = vasoconstrictor secreted by endothelial cells
______ in the cell membrane of gram-negative bacteria can cause rapid-onset fever and hypotension due to activation of *toll-like receptors* on cells of the *innate immune system*.
Endotoxin - Pattern recognition receptors (PRRs) are part of the innate immune response; they recognize damaged host proteins or conserved microbial molecules and trigger inflammation. - Toll-like receptors, a type of PRR on macrophages and dendritic cells, recognize lipopolysaccharide and promote the release of inflammatory cytokines (eg, IL-1/6/12, TNF-alpha) via NF-kB signaling.
What drug binds gp41, inhibiting HIV viral entry?
Enfuvirtide [fusion inhibitor] (AE: Skin rxn at injection sites) - gp41 mediates fusion of the viral cell membrane with the host cell membrane, thereby allowing the viral core to enter the cell.
Colon biopsy findings (not colonoscopy): Trophozoites containing red blood cells
Entamoeba histolytica
Indole positivity (ability to convert tryptophan to indole) of E coli distinguishes it from _______ , another lactose-fermenting gram-negative rod that is a common cause of UTIs in
Enterobacter cloacae (E coli is indole positive)
Nematode route of infection: Ingested
Enterobius Ascaris Toxocara Trichinella Trichuris "you get sick if you EATTT these"
_________ infection (enterobiasis) occurs most frequently in children and presents with perianal pruritus. Diagnosis is made by identifying eggs in the perianal region (cellulose tape test).
Enterobius vermicularis
What can grow in broth containing hypertonic saline?
Enterococci
The duodenal brush border enzyme _______ activates trypsin from its inactive precursor, trypsinogen.
Enteropeptidase - Trypsin degrades complex polypeptides to dipeptides, tripeptides, and amino acids while activating other pancreatic enzymes. - Enteropeptidase deficiency impairs both protein and fat absorption, leading to diarrhea, failure to thrive, and hypoproteinemia.
Analysis of the cerebrospinal fluid (CSF) shows normal glucose, marginally elevated protein (generally <150 mg/dL), and pleocytosis with a lymphocytic predominance. This pattern suggests aseptic meningitis, which is usually (due to these parameters) due to
Enteroviruses (eg, coxsackievirus, echovirus, poliovirus) - lumbar puncture indicates viral cause
- Infiltration of eosinophils in the esophagus often in atopic patients. - Food allergens --> dysphagia, food impaction. - Esophageal rings and linear furrows often seen on endoscopy. - Typically *unresponsive to GERD therapy*
Eosinophilic esophagitis - eosinophils seen in GERD, etc. --> eosinophilic esophagitis is characterized histologically by numerous superficially located intraepithelial eosinophils, which can help differentiate it from reflux esophagitis.
- child - pseudorosette - tumor lining 4th ventricle --> obstructive hydrocephalus - GFAP positive
Ependymoma - Also seen in NF2
Glioblastoma is associated with oncogenic mutations that increase _______ expression on the tumor cells
Epidermal Growth Factor Receptor - Also seen in non-small cell lung cancer, breast cancer, prostate cancer - Drugs that inhibit the EGFR/EGFR-ligand interaction (eg, erlotinib) are often used as part of treatment.
________ is a group of inherited disorders characterized by epithelial fragility (eg, bullae, erosions, ulcers) triggered by minor trauma
Epidermolysis bullosa - LM: intraepidermal cleavage -ex: kid who has continuous bullae on feet that constantly rupture easily
_______ causes rapidly progressive airway obstruction and classically presents with fever, dysphagia, drooling, *inspiratory stridor*, and tripod positioning [leaning forward with neck extended]. Individuals with incomplete immunization against _______ are at greatest risk
Epiglottitis Haemophilus influenzae type b - X-ray = "Thumb sign" (enlarged epiglottis) - clinical features: Distress (tripod position, sniffing position, stridor), Dysphagia, dysphonia, Drooling, High fever
______ histopathology shows inflammation in the subcutaneous fat (panniculitis) with edema, fibrinous exudate, and a variable cellular infiltrate (neutrophils, lymphocytes, histiocytes).
Erythema nodosum
The use of lactose fermentation as a source of energy is best known in ________ with the well studied lac operon, an inducible and repressible genetic sequence coding for the enzymes necessary for lactose fermentation in the absence of glucose. It is activated by a sensed glucose deficit and repressed when glucose is available again.
Escherichia coli
_______- presents with progressive solid food dysphagia. It is diagnosed with contrast imaging (eg, barium swallow) rather than manometry. However, most patients will have a long history of gastroesophageal reflux with decreased tone at the LES.
Esophageal stricture
Stress incontinence
Etiology: - ↓ Urethral sphincter tone - Urethral hypermobility Symptoms: Leakage with coughing, lifting, sneezing - Associations: Obesity, vaginal delivery, prostate surgery - Treatment: Pelvic floor muscle strengthening (Kegel) exercises, weight loss, pessaries
Overflow incontinence
Etiology: - Impaired detrusor contractility - Bladder outlet obstruction - Symptoms: Incomplete emptying & persistent involuntary dribbling - Associations: Polyuria (eg, diabetes), bladder outlet obstruction (eg, BPH), neurogenic bladder (eg, MS) - Treatment: Catheterization, relieve obstruction (eg, α-blockers for BPH)
______ is characterized by a low T3 level, normal thyroid-stimulating hormone (TSH), and normal T4.
Euthyroid sick syndrome (ESS) (also known as low T3 syndrome) - In severe illness, high levels of cortisol, inflammatory cytokines, and free fatty acids suppress deiodination of T4, resulting in lower circulating levels of T3. - Concurrently, upregulation of 5'-deiodinase type III leads to increased conversion of T4 to reverse T3 (inactive form). - ESS is thought to be a form of mild, transient central hypothyroidism, intended to decrease maladaptive catabolism in severe illness; treatment with exogenous thyroid hormone does not improve outcomes and is not indicated.
GLUT-4 is found in skeletal muscle (and adipose tissue?). What increases its expression/translocation to the cell surface?
Exercise [muscle contraction] and Increased Insulin [fed state] - Over time, regular exercise causes increased expression of GLUT4, leading to increased skeletal muscle glucose uptake at any given insulin level and therefore lower blood glucose levels. - Exercise-induced hypoglycemia is common in patients with diabetes mellitus due to the lack of physiologic insulin regulation along with insufficient carbohydrate supplementation. - In normal individuals, overt hypoglycemia does not occur with exercise because a drop in blood glucose suppresses insulin release from the beta cells, and counterregulatory hormones (eg, glucagon) increase endogenous glucose production via glycogenolysis and gluconeogenesis. However, patients taking exogenous insulin are vulnerable to exercise-induced hypoglycemia because insulin will continue to be released from the injection site despite falling glucose levels.
Seborrheic keratosis is often associated with activating mutations of
FGFR3
What hormone increases during Menopause?
FSH - During the menopausal transition, FSH levels increase due to resistant ovarian follicles and lack of feedback from inhibin. Absence of menstrual cycles with associated hypoestrogenic symptoms (eg, hot flashes, vaginal dryness) is highly suggestive of menopause. - Menopause is typically diagnosed clinically. However, if the diagnosis is unclear, an elevated serum FSH level can be used for diagnosis as it is a reliable early indicator.
_________ involves the conscious and deceptive feigning or self-production of physical or psychological symptoms to obtain attention and medical care from health care personnel.
Factitious disorder - Malingering is differentiated from factitious disorder by the intentional falsification of symptoms for personal gain (eg, financial benefits, time off from work). In contrast, factitious disorder requires the absence of obvious rewards.
Pt has increased bleeding time, with normal PT and PTT, and is classically bleeding from umbilical stump after delivery:
Factor 8 deficiency
The classic clinical presentation includes failure to thrive, polyuria, polydipsia, and rickets.
Fanconi syndrome
- Pre- and postnatal developmental retardation - microcephaly - facial abnormalities A (eg, smooth philtrum, thin vermillion border, small palpebral fissures) - limb dislocation - heart defects - Heart-lung fistulas and holoprosencephaly in most severe form.
Fetal alcohol syndrome - One mechanism is due to impaired migration of neuronal and glial cells.
- Bundles of spindle-shaped fibroblasts - Meigs syndrome—triad of ovarian fibroma, ascites, pleural effusion. - "Pulling" sensation in groin.
Fibroma (benign) - sex cord stromal tumor
Most common in women 20-50 years old. Chronic, widespread musculoskeletal pain associated with "tender points," stiffness, paresthesias, poor sleep, fatigue, cognitive disturbance
Fibromyalgia - cognitive disturbance = "fibro fog" - diffuse musculoskeletal pain that worsens with weather changes, psychological stress, or reduced sleep. It does not cause joint deformities. - The etiology of fibromyalgia is unknown, but it likely involves abnormal central processing of painful stimuli. - Treatment: regular exercise, antidepressants (TCAs, SNRIs), neuropathic pain agents (eg, gabapentin). -- Although initially painful, aerobic exercise helps to improve pain and functioning in these patients.
!!! What is the main drug used to treat BPH? What is its MOA?
Finasteride - Prostate growth is driven by DHT --> Finasteride is a 5-alpha reductase inhibitor - reduces prostate volume - acts on epithelium [hyperplasia on stroma and epithelium in BPH]
What is the treatment for Candida esophagitis/vaginitis?
Fluconazole
_______ causes nephrotic syndrome due to direct (eg, cytotoxic drugs) or indirect (eg, glomerular hyperfiltration) podocyte injury.
Focal Segmental Glomerular Sclerosis
Which type of thyroid carcinoma invades capsules and lymph nodes?
Follicular - Follicular neoplasms typically present as slowly enlarging, painless thyroid nodules. Differentiation between a follicular adenoma and follicular thyroid carcinoma is not possible using only fine-needle aspiration results. Histologic evidence of invasion of the tumor capsule and/or surrounding blood vessels is needed to diagnose follicular thyroid carcinoma. - This propensity of follicular thyroid carcinomas to invade surrounding blood vessels accounts for their tendency to metastasize via hematogenous spread to distant tissues (eg, bone, lung).
- Distention of unruptured Graafian follicle. - May be associated with hyperestrogenism/endometrial hyperplasia. - Most common ovarian mass in young women.
Follicular Ovarian cyst
The presence of colloid-containing microfollicles suggests a benign
Follicular adenoma
Microdeletion is the loss of genetic material too small to be visible via light microscopy. Whats an example?
For example, microdeletion of 22q11 is responsible for DiGeorge syndrome.
Duchenne muscular dystrophy type of mutation
Frameshift --> disrupts reading frame --> early stop codon
Frataxin gene mutation
Friedreich ataxia
_______ is an autosomal recessive trinucleotide repeat disorder that presents during childhood with ataxia, loss of vibration/proprioception sense, and skeletal abnormalities (eg, kyphoscoliosis, pes cavus)
Friedreich ataxia
Rb gene blocks what part of cell cycle?
G1 --> S
________ are characterized by aggregates of nevus cells limited to the dermoepidermal junction (Choice C). They typically appear as flat, black- to brown-pigmented macules with darker coloration in the center than the periphery and preserved skin markings.
Junctional nevi
Do GLP-1 agonists or DPP-4 antagonists cause weight loss?
GLP-1 does, DPP-4 is weight neutral
______ is found primarily in the liver and pancreatic beta cells, where it facilitates insulin-independent glucose uptake.
GLUT2 - It is not expressed significantly in muscle or translocated in response to muscle contraction.
_______ occurs when a large gallstone erodes into the intestinal lumen and becomes impacted (eg, at the ileocecal valve), causing mechanical obstruction.
Gallstone ileus - CT scan commonly shows obstructing gallstones or pneumobilia due to retrograde passage of intestinal gas into the biliary tract. - Gallstone ileus is a mechanical bowel obstruction caused when a large gallstone erodes into the intestinal lumen. - *Pneumobilia (air in the biliary tract) is a common finding.* - Typical symptoms of gallstone ileus include crampy pain, vomiting, and bloating. Examination will show signs of small bowel obstruction, such as abdominal distension, tenderness, and high-pitched (tinkling) bowel sounds. Abdominal radiographs may reveal dilated bowel loops with air-fluid levels. Careful inspection may also reveal air in the biliary tree (pneumobilia) due to retrograde passage of intestinal gas through the fistula.
- Connective tissue outpouching arising from tendon sheaths and joint structures (herniation of dense connective tissue) - Round, firm, well-circumscribed - Transilluminates on penlight examination - Wrist (most common), dorsal foot, knee
Ganglion Cyst [most resolve spontaneously]
______ are benign, fluid-filled masses that occur due to mucoid degeneration of periarticular tissue.
Ganglion cysts - They present as painless, smooth, rubbery, round structures that overlie joints (eg, wrist) or tendons and transilluminate with a penlight. - However, some patients may experience mild aching, and significant compression can occasionally result in paresthesia or weakness. Physical examination reveals a smooth, rubbery, round structure that overlies a joint or tendon and transilluminates with a penlight. Most ganglion cysts resolve spontaneously without intervention. - Most resolve spontaneously without intervention.
______ present as painless, smooth, rubbery, round structures that overlie joints (eg, wrist) or tendons and transilluminate with a penlight.
Ganglion cysts - benign, fluid-filled masses that occur due to mucoid degeneration of periarticular tissue. - However, some patients may experience mild aching, and significant compression can occasionally result in paresthesia or weakness. Physical examination reveals a smooth, rubbery, round structure that overlies a joint or tendon and transilluminates with a penlight. Most ganglion cysts resolve spontaneously without intervention. - Most resolve spontaneously without intervention.
Leser-Trélat sign = rapid onset of multiple Seborrheic Keratoses --> indicates which possible malignacy?
Gastric adenocarcinoma - Microscopic examination shows small cells resembling *basal cells*, with pigmentation, hyperkeratosis, and keratin-containing cysts.
Tumor Marker: Carcinoembryonic antigen (CEA) Associations: ???
Gastrointestinal (ex: colorectal) - Carcinoembryonic antigen is a serum marker that is primarily used to monitor response to treatment in patients with colorectal cancer.
Endometritis treatment
Gentamicin + Clindamycin +/- ampicillin
- Elderly female - pain on chewing - high ESR - possible vision loss - possible pain and stiffness in proximal muscles (shoulders/hips)
Giant Cell Arteritis - granulomatous inflammation of the media with fragmentation of the internal elastic lamina Possible pain and stiffness in proximal muscles (shoulders/hips) = polymyalgia rheumatica - fever, malaise, weight loss - no muscular weakness
Stool inspection for ova and parasites can identify infectious causes of malabsorption such as ...
Giardia and Cryptosporidium
- Reabsorption defect of NaCl in DCT - Metabolic alkalosis, hypomagnesemia, hypokalemia, hypocalciuria
Gitelman Syndrome - Autosomal Recessive - Presents similarly to lifelong thiazide diuretic use - Less severe than Bartter syndrome
In _________ , blood smear will show no platelet clumping
Glanzmann Thrombasthenia
What are the long acting insulin analogues?
Glargine Degludec Detemir
_______ is an arrangement in which an insurer pays a provider a single payment to cover all the expenses associated with an incident of care.
Global payment - This is most commonly done for elective surgeries, in which the global payment covers the surgery as well as any pre- and post-operative visits needed.
A benign ________ can produce a very tender, small , red-blue lesion under the nail bed. This type of tumor originates from the modified smooth muscle cells that control the _________ functions of dermal glomus bodies.
Glomus tumor (Glomangioma) thermoregulatory *[may also be subungal melanoma which is involved in pigmentation]*
_______ presents with hyperglycemia (often as newly diagnosed diabetes mellitus) and necrolytic migratory erythema (blistering erythematous plaques with central clearing) affecting the groin, face, and extremities.
Glucagonoma - Can also get GI symptoms (diarrhea, anorexia, abdominal pain) - A characteristic skin finding is necrolytic migratory erythema, an elevated painful and pruritic rash typically affecting the face, groin, and extremities. Over time, small erythematous papules coalesce to form large, indurated plaques with a central clearing that often appears brown or bronze-colored - The diagnosis is made by detecting elevated glucagon levels. - Glucagon acts on the liver to promote amino acid oxidation and gluconeogenesis from amino acids. Circulating levels of amino acids are low in glucagonoma and thought to contribute to development of necrolytic migratory erythema.
_______ is a precursor for the inhibitory neurotransmitter GABA
Glutamic acid
What is the VAP for RSV?
Glycoprotein is the VAP Fusion protein is for fusion to host membrane
Intermittent anovulatory cycles are common in the first few years after menarche due to an immature hypothalamic-pituitary-ovarian axis producing *low and irregular ______ pulses*. As a result, adolescent girls may have menstrual cycle variability with intermenstrual spotting and heavier menstrual bleeding.
GnRH - Adolescent girls typically have an immature hypothalamic-pituitary-ovarian axis for several years following menarche because the hypothalamus' pulsatile release of GnRH is low and irregular. This results in decreased gonadotropin (FSH, LH) levels with an inability to mount an LH surge, leading to anovulation and cycles without progesterone secretion. - Without progesterone, the endometrium remains in the proliferative phase and can become disorganized and fragile with unstable vasculature, resulting in longer menstrual cycles with irregular bleeding and intermittent spotting
In Kallmann syndrome, there is an absence of _______ secretory neurons in the hypothalamus due to defective migration from the olfactory placode.
GnRH - These patients have central hypogonadism and anosmia, and often present with delayed puberty. - Mutation in the KAL-1 gene or the fibroblast growth factor receptor-1 gene, which normally codes for proteins required in this migration.
What drugs can cause membranous nephropathy?
Gold NSAIDs Penicillamine
Linear deposits of IgG and C3 along GBM =
Goodpasture syndrome
Risk factors for uric acid stone formation
Gout Myeloproliferative disorders
Depletion of donor CD3+ T cells prior to transplant decreases the risk of ______
Graft vs Host Disease - but also decreases the beneficial graft versus tumor effect, increasing the likelihood of cancer relapse. Etiology - Most commonly occurs after allogeneic hematopoietic cell transplant - Donor CD3+ T cells recognize host cells as foreign → widespread, multisystem inflammatory response - Increased risk with:HLA mismatch - Lack of pretransplant CD3+ T-cell depletion Clinical manifestations - Skin: maculopapular rash, which can progress to bullous lesions - Liver: abnormal function tests (eg, increased bilirubin & alkaline phosphatase) - Gastrointestinal tract: diarrhea, abdominal pain, nausea & vomiting
Transplant Reaction: - Rash (maculopapular, may desquamate) - Diarrhea, abdominal plain - Increase Liver Function Tests - Increased bilirubin
Graft vs Host Disease - mostly a complication of bone marrow transplant - Donated (graft) CD8 T cells react to recipient cells
Strep pneumonia shape
Gram positive dipplococci
Listeria genome
Gram positive rod tumbling motility Anaerobic (facultative) beta hemolytic
Salmonella shape? Oxidase positive or negative?
Gram-negative oxidase-negative rod - Patients with sickle cell disease are at increased risk of septic arthritis due to salmonella.
- Unilateral and large - Predominantly women in their 50s. - Often produces *estrogen* and/or progesterone - Presents with postmenopausal bleeding, endometrial hyperplasia, sexual precocity (in pre- adolescents), breast tenderness. -Histology shows Call-Exner bodies - In young patients, excessive estrogen levels may cause precocious sexual development.
Granulosa cell tumors - Most common malignant sex cord stromal tumor. - Secretes estrogen and can present with endometrial hyperplasia (eg, postmenopausal bleeding with thickened endometrium on ultrasound). The unopposed estrogen leads to hyperplasia of the endometrial cells and glands, and the increased cellular division of the hyperplastic cells in turn increases the risk of cellular atypia and endometrial carcinoma. In young patients, excessive estrogen levels may cause precocious sexual development. - Call-Exner bodies = granulosa cells arranged haphazardly around collections of eosinophilic fluid, resembling primordial follicles --> "Give Granny a Call!" - On gross pathology, the tumor appears yellow due to the lipid content in theca cells. - The granulosa cells are small and cuboidal in shape, grow in cords or sheets, and form follicle- or rosette-like structures (Call-Exner bodies) that have a gland-like appearance with a pink eosinophilic center and coffee bean nuclei. - Theca cells are plump with lipid contents, which give the mass a yellow color on gross inspection.
Pretibial myxedema and ophthalmopathy are specific features of ________ disease.
Graves - They are caused by an autoimmune response directed against the TSH receptor that results in the accumulation of glycosaminoglycans within the affected tissues.
Hyperplastic follicles with tall, crowded cells forming intrafollicular projections can be seen in ____________ , often with hyperactive resorption of colloid leading to scalloping of the colloid edges
Graves disease
In _________ , microscopy shows hyperplastic follicles with tall, crowded follicular epithelial cells projecting into the follicular lumen; hyperactive reabsorption causes scalloping around the edges of the colloid.
Graves disease
Renal papillary necrosis classically presents with
Gross hematuria, Acute flank pain, Passage of tissue fragments in urine. - It is most commonly seen in patients with sickle cell disease or trait, diabetes mellitus, analgesic nephropathy, or severe obstructive pyelonephritis.
_____ antagonists block gastric acid secretion by parietal cells.
H2 - H2 receptors are found on parietal cells in the gastric mucosa.
The presence of ___________ in the mother greatly increases the risk of vertical transmission of the Hep B virus
HBeAg (a marker of viral replication and increased infectivity) - Hepatic injury from hepatitis B is due to the cellular immune response, not by the virus itself. Therefore, infants with HBV infection enter an immune-tolerant phase due to their immature T-cell responses, which limits hepatocyte damage. As a result, laboratory markers of liver injury (eg, liver function tests, direct bilirubinemia) are usually normal or only mildly elevated in HBV-infected neonates. - Side note: HBcAg is not detectable in serum - Side note: HBsAg is the first virological marker detected in the serum after inoculation, preceding both the elevation of serum aminotransferases and the onset of clinical symptoms. It remains detectable during the entire symptomatic phase of acute hepatitis B and suggests infectivity.
_____ is a non-immune-mediated condition caused by platelet clumping. Most cases arise within 2 days of heparin administration.
HIT type 1 - Thrombocytopenia is typically mild (nadir ~100,000/mm3) - It does not cause thrombosis and is not considered clinically significant; therefore, *heparin can be continued.*
Crohn Disease HLA
HLA DR7 and DQ4
Ulcerative colitis HLA
HLA DRB1 - better with smoking - p-ANCA
Type 1 DM is associated with which HLAs?
HLA-DR3 and DR4
Rheumatoid Arthritis HLA
HLA-DR4 (4-walled rheum)
- Multiple, painful, superficial vesicles or ulcerations with erythematous base - Initial infections also have systemic symptoms (eg, fever, headache, myalgia) and tender lymphadenopathy.
HSV
Which esophagitis has the following microscopic findings: Small vesicles →"punched-out" ulcers
HSV-1 Microscopic findings: Eosinophilic intranuclear inclusions (Cowdry type A) in multinuclear squamous cells at ulcer margins
- painful genital ulcers with an erythematous base - matted/suppurative lymphadenitis - typically begin as papules or pustules and evolve into an ulcer
Haemophilus ducreyi - small gram-negative rod - causes chancroid
- Child - URI - Melena - abdominal pain - palpable purpura - possible kidney problems
Henoch-Schonlein Purpura - tissue biopsy = best test (will show IgA deposition)
Lichen planus is associated with what?
Hep C
Interferons α and β are produced by most human cells in response to viral infections. The production of α and β interferons helps suppress viral replication by
Halting protein synthesis Promoting apoptosis of infected cells, limiting the ability of viruses to spread through the tissues. - *Interferons α and β* induce MHC class I expression on all cells and stimulate the activity of natural killer (NK) and cytotoxic T cells. These processes act to increase the proportion of virally infected cells that undergo apoptosis. - *Interferon γ* is a type II interferon produced mainly by T cells and NK cells. It promotes TH1 differentiation, increases expression of class II MHC molecules on antigen-presenting cells, and improves the intracellular killing ability of macrophages. However, virally infected respiratory epithelial cells would secrete interferons α and β, not interferon γ.
Does Hb levels go up or down during pregnancy? What about plasma volume and RBC mass?
Hb levels go down Plasma volume and RBC mass go up (but Plasma volume goes up greater than RBC mass) [platelet count does not increase though] - *However*: Gestational thrombocytopenia is common in the third trimester and is typically mild, asymptomatic, and not associated with other laboratory abnormalities. It occurs due to hemodilution (ie, maternal plasma volume expansion) and increased sequestration/consumption of platelets in the placenta.
Traveller's diarrhea is caused by enterotoxigenic e coli, which has what plasma encoded toxins (plus what are there effects)?
Heat labile toxin (LT) - similar to cholera toxin (vibrio cholera) and anthrax toxin (anthrax toxin = mimics adenyl cyclase) - also similar to 1 of 2 toxins from B pertussis -- Adenylate cyclase toxin: Functions as an adenylate cyclase, increasing cAMP levels; causes edema & phagocyte dysfunction -- *contrast*: Pertussis toxin: B. pertussis permanently disables Gi --> increases cAMP --> edema/phagocyte disfunction --> whooping cough - Activates *Gs* - Over-activates Adenylyl cyclase via ribosylation of Gs by adenosine diphosphate (ADP) --> increases cAMP --> increases Cl efflux (Na and H20 follow) Heat Stabile toxin (ST) - Not inactivated by heat - similar to Y enterolytica (enterotoxin) - Overactivates guanylate cyclase --> increases cGMP --> decrease resorption of NaCl and H20 in gut
What is the VAP for parainfluenza virus?
Hemagglutinin-Neuramidase (HN)
What is the VAP for influenza virus (and what does it bind to)?
Hemagluttinin (a surface glycoprotein)is for viral entry (binds to sialic acid) Neuramidase is for virion release - increases IFN-alpha - Poor proofreading of viral RNA-dependent RNA polymerase, which results in the introduction of genetic mutations during replication (*antigenic drift*). - Reassortment of the *segmented* genome when 2 influenza viruses infect the same cell, which results in dramatic alterations to the genome (*antigenic shift*) [genetic reassortment]. - Antigenic changes to hemagglutinin can alter the tissue tropism of the virus and allow strains that previously only affected livestock (eg, avian, swine) to infect human cells.
______ is secreted by Staph aureus and it destroys RBCs, neutrophils, and platelets
Hemolysin
Hereditary spherocytosis causes what kind of anemia?
Hemolytic anemia (but not autoimmune --> so will have negative coombs test) Pt will have: - Increased reticulocytes: Reticulocytes are larger than mature red blood cells (RBCs), lack central pallor, and have a bluish coloration (polychromatic RBCs) due to the presence of ribosomes, which are not found in mature RBCs. Increased reticulocytes in the peripheral blood is a nonspecific finding that indicates the bone marrow is responding appropriately to anemia by increasing production of new erythrocytes. - Spherocytes: Spherocytes are erythrocytes with reduced cell membrane, which makes the cell spherical rather than biconcave. In otherwise healthy individuals, spherocytes generally arise in the setting of immune-mediated hemolytic anemia; in this condition, IgG-coated erythrocytes are partially phagocytized by splenic macrophages, which reduces the surface area of the erythrocyte cell membrane, thereby causing the erythrocyte to assume a spherical shape. - Nucleated erythrocytes: Nucleated erythrocytes are very immature RBCs. The presence of nucleated RBCs in the peripheral blood indicates a strong bone marrow response to compensate for the anemia.
- Rare, benign liver tumor - often related to oral contraceptive or anabolic steroid use - may regress spontaneously or rupture (abdominal pain and shock).
Hepatic adenoma - Jaundice and weight loss are unexpected - An abdominal CT scan usually demonstrates a solitary lesion in the hepatic parenchyma. - Histology reveals relatively uniform hepatocytes arranged in thin cell plates without atypia.
_______ infection is associated with porphyria cutanea tarda, which presents with skin fragility and a blistering rash in sun-exposed areas, and mixed cryoglobulinemic vasculitis, which presents with nonblanching palpable purpura.
Hepatitis C
Carcinogen: Aflatoxins Cancer: ???
Hepatocellular carcinoma (liver) Exposure: stored grains and nuts
- Hyperpigmentation - Arthritis (particularly 2nd & 3rd MCP joints) - Chondrocalcinosis - Elevated liver enzymes, hepatomegaly (early) - Cirrhosis & hepatocellular carcinoma (late) - Diabetes mellitus - Hypopituitarism (eg, secondary hypogonadism, hypothyroidism; sexual disfunction) - Restrictive or dilated cardiomyopathy - Conduction abnormalities
Hereditary Hemochromatosis
_________ is characterized by recurrent episodes of cutaneous and/or mucosal swelling due to C1 inhibitor deficiency.
Hereditary angioedema - Attacks are often precipitated by minor trauma (eg, dental procedure) or emotional stress and are *not associated* with itching or urticaria. - Poor C1 inhibitor function leads to elevated bradykinin, a peptide that causes vasodilation and increased vascular permeability, resulting in edema. - C4 levels are low due to uninhibited cleavage of C4 by excess activated C1.
______ occurs due to a defect in DNA mismatch-repair enzymes. It leads to increased susceptibility to colon cancer.
Hereditary nonpolyposis colorectal cancer (HNPCC)
______ describes the presence of different mitochondrial genomes (eg, mutated and wild type) within a single cell.
Heteroplasmy - The severity of mitochondrial diseases is often related to the proportion of abnormal to normal mitochondria.
_______ is characterized by painful, deep-seated nodules and scar formation in the axillae, groin, and medial thighs. The pathogenesis of HS begins with the occlusion of ______ caused by keratinocyte hyperproliferation and abnormal keratinocyte differentiation.
Hidradenitis suppurativa (HS) folliculopilosebaceous units - Mechanical stress (eg, friction in intertriginous areas) then leads to follicular rupture and the release of proinflammatory contents. - Contributing factors include tobacco use, immune dysregulation, hormonal factors (eg, excessive androgen effect), and bacterial colonization/infection. - HS is a chronic, recurring condition with progressive formation of draining abscesses, sinus tracts (formed by epithelial stem cells released from follicular rupture), comedones (from significant follicular damage), and extensive fibrosis. In contrast to common furuncles and carbuncles, which usually resolve completely with drainage and antibacterial therapy, HS may persist and recur despite months of antibiotic therapy.
Loss of function of RET is seen in
Hirschprung
Where is the block usually seen in Mobitz Type 2?
His-Purkinje system - like 3rd degree (complete) AV block [His is most likely pacing the ventricles; will cause narrow QRS; Purkinje automaticity = tachycardia + wide QRS]
Where is the block usually in 3rd degree complete AV block?
His-Purkinje system [His is most likely pacing the ventricles; will cause narrow QRS; Purkinje automaticity will cause wide QRS + tachycardia]
Exposure to bats (eg, during cave exploration) or to bird droppings in the Ohio and Mississippi River Valley areas is associated with __________ infection, which typically causes lung disease resembling tuberculosis.
Histoplasma capsulatum
_______ is a dimorphic fungus that exists as a small, ovoid yeast at tissue temperatures. It replicates within macrophages and spreads through the lymphatic and reticuloendothelial system. Immunocompetent patients usually have an asymptomatic pulmonary infection, but those who are immunocompromised (eg, advanced AIDS) can develop *disseminated disease to the liver, spleen, and bone marrow*.
Histoplasma capsulatum - Disseminated infection is often diagnosed when histopathology shows oval or round *yeasts within macrophages*. - Culture on Sabouraud agar grows hyphae (Histoplasma is a mold at cooler temperatures). Histoplasma antigen in blood and urine can also be detected by immunoassay.
Ohio and Mississippi River valleys. Soil, bird and bat droppings (chicken coops, caves).
Histoplasma capsulatum - clinical presentation: Pulmonary: similar to tuberculosis (lung granulomas with calcifications). Disseminated: lungs, spleen, liver - Lab dx: Culture (25ºC): branching hyphae. Biopsy: oval yeast cells within macrophages.
__________ Histoplasma capsulatum is grows well in acidic soil with high nitrogen content [enriched with bird or bat droppings]
Histoplasma capsulatum grows well in acidic soil with high nitrogen content [enriched with bird or bat droppings] - Birds/bat roosts (contrasts with cryptococcus) - Old/decaying buildings Demolition/ reconstruction - Rotting trees Nonencapsulated yeast, thick walled and narrow base/small budding yeasts in alveolar macrophages Microconidia and hyphae are inhaled and phagocytosed by alveolar macrophages, which travel to local lymph nodes through the blood to other body locations Hilar lymphadenopathy Oval yeasts in macrophages Positive urine antigen test, also seen in: Legionella Strep pneumoniae Xray of lungs: Calcified coin lesions [oval yeasts [aerial hyphae] in macrophages?) Other signs/symptoms: - Tb-like pulmonary lung disease - Palatal/tongue ulcers - Splenomegaly - Pancytopenia - Erythema nodosum
______ is due to failure of the primitive forebrain (prosencephalon) to divide into the right and left hemispheres, resulting in a spectrum of brain and midface abnormalities (eg, facial clefts, cyclopia). ______ is the most commonly associated etiology.
Holoprosencephaly Trisomy 13 (patau syndrome) - Fetal brain development begins at week 3, when the ectodermal cells thicken and invaginate to form the neural tube, which differentiates into the primitive forebrain (prosencephalon), midbrain (mesencephalon), and hindbrain (rhombencephalon). - The prosencephalon gives rise to the diencephalon, which develops into the thalamus and third ventricle, and telencephalon, which develops into the cerebral hemispheres and lateral ventricles.
_________ infections are transmitted via direct contact between human skin and contaminated soil/sand (eg, walking barefoot). Dermal penetration is often characterized by an intensely pruritic papule that may form serpiginous tracks due to the subcutaneous migration of larvae.
Hookworm - Deeper spread may occur, depending on the species of infecting hookworm, as follows: - Human hookworms (eg, Necator americanus, A duodenale) penetrate the basement membrane and spread from the dermis to the bloodstream. They rupture into the alveoli and are coughed up and swallowed into the small intestine. There, larvae mature into adult hookworms that feed on blood from the duodenal mucosa (often causing iron deficiency anemia) and shed up to 10,000 eggs/day, thereby spreading the infection to others. - Cat and dog hookworms (eg, Ancylostoma braziliense, A caninum) cause a dermal eruption in humans but are unable to penetrate the cutaneous basement membrane and spread to deeper tissues. Therefore, larvae do not mature into adult hookworms or spread from human-to-human (humans are incidental hosts).
- chronic atopic dermatitis (eczema) - recurrent sinopulmonary infections - Non-inflammatory (*cold*) abscesses
Hyper IgE syndrome - caused by impaired neutrophil activation and migration due to a defect in T-helper cell type 17 cells - decreased IFN-gamma - increased IgE, other Ig levels normal
Transplant Rxn: - preformed host antibodies against donor ABO or HLA (major histocompatibility complexes). - Histology generally shows fibrinoid necrosis with hemorrhage and ischemia ("white graft" reaction).
Hyperacute rejection
Risk factors for Calcium stone formation:
Hypercalciuria (eg, hyperparathyroidism) Hyperoxaluria (eg, malabsorption,low-calcium diet) Hypocitraturia (eg, distal RTA) Diet: ↑ sodium, ↑ protein, ↑ oxalate, ↓ calcium
________ is a refractive error characterized by a reduced anterior-posterior diameter of the eye, causing the focal point of the refracted image to be positioned posterior to the retina.
Hyperopia (farsightedness) - In contrast to myopia, hyperopia causes blurred vision of nearby objects and is corrected by a converging (convex) lens.
_______ occurs from global interruption of the cerebral blood supply (eg, due to cardiac arrest).
Hypoxic encephalopathy - It commonly presents with decreased consciousness (eg, coma, vegetative state) as opposed to focal neurologic deficits. - Cerebral imaging may show watershed infarcts at the border of perfusion zones between the major cerebral arteries.
Hypomagnasemia's effect on PTH?
Hypoparathyroidism can be caused by severe hypomagnesemia, which can be seen with prolonged diarrhea In hypoparathyroidism, low serum PTH is accompanied by hypocalcemia and an increase in serum phosphorus
_______ myopathy presents with myalgias, proximal muscle weakness, elevated creatine kinase levels, and delayed relaxation of deep tendon reflexes.
Hypothyroid - The diagnosis can be confirmed with an elevated TSH level. - Myoedema (focal muscle contraction at the site of percussion) and delayed relaxation of deep tendon reflexes are characteristic findings that are caused by impaired reuptake of calcium by the sarcoplasmic reticulum. - Other common causes of myopathy with elevated creatine kinase levels include inflammatory myopathies, muscular dystrophies, and HMG-CoA reductase inhibitors.
Which cytokines plays a role in reducing the immune response?
IL-10 (anti-inflammatory) and TGF-beta (anti-inflammatory and pro-fibrotic)
Patients with uncontrolled DM typically have non-healing wounds due to high blood glucose releasing ROS and pro-inflammatory cytokines from neutrophils, while inhibiting GF needed for fibroblast proliferation and re-epithelialization. Upregulation of what can fix this?
IL-10 production by macrophages
Induces differentiation of T cells into Th1 cells, and Activates NK cells.
IL-12 [secreted by macrophages]
The pathogenesis of ankylosing spondylitis likely originates with defects in the intestinal mucosal barrier and exposure to the gut microbiome that lead to an enhanced _____-mediated inflammatory response, which stimulates production of additional inflammatory factors, primarily ______ and ______, which have synergistic proinflammatory effects and induce bony erosions and abnormal bone regrowth in the skeleton.
IL-17 tumor necrosis factor-alpha and prostaglandins
_______ , stimulated by all T cells, Stimulates growth of helper, cytotoxic, and regulatory T cells, and NK cells.
IL-2
_______ , secreted by all T cells, supports growth and differentiation of bone marrow stem cells. Functions like GM-CSF.
IL-3
Eosinophil proliferation and activation during multicellular parasitic infection is stimulated by _____ produced by TH2 and mast cells
IL-5
_____ contributes to B cell differentiation in addition to its role in stimulating IgA production and eosinophil activity (eg, host defense against parasitic infections).
IL-5
Major chemotactic factor for neutrophils.
IL-8 [secreted by macrophages]
A Th2 cytokine profile consists of...
IL4, IL5, and IL10 ex: Lepromatous leprosy accumulates acid-fast bacilli in macrophages and activates a Th2 response [humoral response; no granuloma because granuloma is from Th1 response]
_________ nephropathy frequently presents as *recurrent*, self-limited, painless hematuria
IgA nephropathy (Berger disease) - Episodes occur with URTI (ex: flu like illness) - In contrast, poststreptococcal glomerulonephritis is seen 1-3 weeks after streptococcal pharyngitis and is usually not recurrent.
Immune complex deposit in mesangium =
IgA nephropathy (Berger disease) - occurs with respiratory or GI infection
- Contains fetal tissue, neuroectoderm. - Commonly diagnosed before age 20. - Typically represented by immature/embryonic-like neural tissue.
Immature teratoma (malignant, aggressive) - germ cell tumor
- Adolescent - Primary amenorrhea - Normal secondary sexual characteristics - cyclic abdominal or pelvic pain
Imperforate hymen - Imperforate hymen is caused by incomplete degeneration of the central portion of the fibrous tissue band connecting the walls of the vagina. - Adolescent patients typically present with primary amenorrhea, normal secondary sexual characteristics, and cyclic abdominal or pelvic pain due to accumulation of menstrual blood in the vagina and uterus (eg, hematocolpos).
COPD causes increased pulmonary arterial pressure --> R heart failure (cor pulmonale). But initially, peripheral edema does not develop. Why is that?
In chronic heart failure, *increased lymphatic drainage* initially offsets factors favoring edema, whereas acute changes (eg, venous thrombosis, heart failure decompensation) are more likely to produce edema. - Severe COPD may cause polycythemia due to hypoxia, but erythrocyte concentration does not affect plasma oncotic pressure (oncotic pressure pulls fluid in, hydrostatic pushes fluid out)
where does blood accumulate in subarachnoid hemorrhage
In the cerebral sulci and basal cisterns
TSH, T3, and T4 levels in primary hypothyroidism
Increased TSH, decreased T4 T3 levels fluctuate rapidly due to its short half life in serum --> therefore, T3 levels may appear normal in primary hypothyroidism
Vasovagal syncope typically involves a trigger (eg, prolonged standing), a prodrome (eg, warmth, light-headedness), and rapid recovery (eg, within 1-2 min). It results from...
Increased parasympathetic output to the heart - a transient, autonomic nervous system-mediated cardioinhibitory and vasodepressor response.
- Age <12 months - Constipation, - poor feeding, - hypotonia - Oculobulbar palsies (eg, absent gag reflex, ptosis) - Symmetric, descending flaccid paralysis
Infant botulism - Ingestion of Clostridium botulinum spores (eg, environmental dust/soil, *honey*) - Spores colonize gastrointestinal tract & produce botulinum toxin - Botulinum toxin inhibits presynaptic acetylcholine release - Confirmation by identification of stool C botulinum spores or toxins
______ runs superiorly and medially up the abdomen, it provides blood supply to the lower anterior abdominal wall. The other main branch off the external iliac artery is the deep circumflex iliac artery, which branches more laterally but also supplies blood to the lower abdominal wall.
Inferior epigastric artery
Colon biopsy findings (not colonoscopy): Spindle-shaped tumor cells with small-vessel proliferation
Kaposi Sarcoma - Skin involvement is characteristic, but extracutaneous spread of KS to the lungs and gastrointestinal tract is also common. - KS lesions are easily distinguished endoscopically. They vary from reddish/violet flat maculopapular lesions to raised hemorrhagic nodules or polypoid masses. - On biopsy, KS lesions will typically show spindle cells with cytologic atypia, blood vessel proliferation, and extravasated red blood cells with hemosiderin deposition.
What is the pathophysiology behind exudative pleural effusion?
Inflammatory increase in vascular membrane permeability (ex: infection [pneumonia, TB], malignancy, rheumatologic disease [connective tissue problem?]) Criteria: Pleural protein/serum protein >0.5 OR Pleural LDH/serum LDH >0.6 OR Pleural LDH >2/3 upper limit of normal of serum LDH
_______ viruses have positive RBC agglutination test
Influenza and Parainfluenza - RSV has a negative test
What have positive RBC agglutination tests?
Influenza and Parainfluenza viruses
What are 2 examples of viruses with segmented genomes?
Influenza virus (orthomyxoviridae) Rotavirus (reoviridae)
_______ refers to the patient's refusal of a recommended medical treatment following an informed consent discussion (including full disclosure of the risks of refusing treatment).
Informed refusal
_______ intoxication is characterized by immediate onset of euphoria, lethargy, ataxia, and/or loss of consciousness followed by rapid recovery within 45 minutes.
Inhalant - Perioral and perinasal dermatitis (ie, "glue sniffer's rash") may be seen in chronic users.
Decreased nasal nitric oxide = used as screening test for ...
Kartagener syndrome
________ occurs when one virus inhibits replication and/or release of a second virus that is infecting the same cell.
Interference
_______ increases expression of MHC class I & II, improving antigen presentation in all cells.
Interferon-gamma
________ is an antiviral cytokine that also decreases inflammatory cell movement across the blood-brain barrier --> analogs can be used to treat multiple sclerosis.
Interferon-β
_______ is characterized by recurrent episodes of explosive verbal or physical aggression. The aggressive behaviors are impulsive and grossly out of proportion to the provocation.
Intermittent explosive disorder - Treatment: Cognitive-behavioral therapy and SSRI
_____ occlusion may occur due to thrombosis or embolism, leading to a transient ischemic attack (TIA) or ischemic stroke. Patients typically have profound neurologic deficits (eg, contralateral homonymous hemianopsia, hemiparesis, hemisensory loss), including cortical signs (eg, aphasia, agnosia, neglect).
Internal carotid artery
Esophageal Varices -> Hematemesis involves which blood supply?
Left gastric (portal system) + azygous and hemiazygous veins
Which TB drug is associated with peripheral neuropathy, which is due to the drug's interference with pyridoxine metabolism and can be prevented by pyridoxine administration?
Isoniazid
________ is an antimycobacterial agent that specifically inhibits the synthesis of mycolic acids, which are essential components of the unique mycobacterial peptidoglycan cell wall.
Isoniazid - Without mycolic acids, the mycobacteria lose their acid-fastness and become unable to synthesize new cell walls or multiply.
Mycobacterial resistance to _______ could be accomplished through non-expression of the catalase-peroxidase enzyme
Isoniazid - or through genetic modification of the INH binding site on the mycolic acid synthesis enzyme
Is DLco decreased or increased in emphysema?
It is decreased (*opposite of other obstructive lung diseases*; *same as restrictive lung disease*) - in other *obstructive*, DLco may be *normal or increased*
How can C diff cause colonic perforation?
It may cause a nonobstructive colonic dilation known as *toxic megacolon*, which can lead to colonic perforation - Clostridioides (formerly Clostridium) difficile infection is associated with yellow-white, patchy pseudomembranes on the bowel mucosa. These pseudomembranes consist of a neutrophil-predominant inflammatory infiltrate, fibrin, bacteria, and necrotic epithelium.
Broca's aphasia involves a stroke of which part of the brain?
Left posterior inferior *frontal* gyrus
Cremaster reflex (testicles move)
L1-L2
_______ has autoantibodies against presynaptic voltage-gated calcium channels
Lamber-Eaton syndrome - causes decreased ACh release and muscle weakness that improves with use
________ = proximal muscle weakness and decreased deep tendon reflexes that improve with exercise
Lambert-Eaton myasthenic syndrome (LEMS) - pt may have autonomic symptoms (dry mouth, impotence)
________ is caused by fibrosis, characterized histologically by homogenization of dermal collagen and is characterized grossly by pigment changes, telangiectasias, and chronic ulceration
Late-stage radiation dermatitis - due to fibroblast activation by transforming growth factor-beta from damaged tissue and responding immune cells - occurs months to years after radiation exposure
Essential HTN causes hypertrophy/thickening of which ventricle?
Left
Wernicke's aphasia involves which artery
Left *inferior* and posterior MCA stroke
Broca's aphasia involves which artery?
Left *superior* MCA stroke
Colon cancers located where tend to infiltrate the intestinal wall and encircle the lumen, causing constipation and symptoms of intestinal obstruction (abdominal pain, distention, nausea)?
Left sided (descending colon) - Right-sided lesions are more likely to bleed and cause iron deficiency anemia; left-sided lesions tend to present with obstructing symptoms (eg, altered bowel habits, constipation, abdominal distension, nausea and vomiting).
________ is a disease of young children that results in isolated idiopathic osteonecrosis of the hip
Legg-Calvé-Perthes disease
________ is a ___(bacteria shape, etc.)____ that can cause *pneumonia* with high fever, cough, *confusion, hyponatremia, and diarrhea*.
Legionella pneumophila facultative intracellular gram-negative bacillus - The most common laboratory abnormality seen with Legionella pneumonia is hyponatremia, and sputum Gram stain often shows many neutrophils but few or no organisms. - The hyponatremia may be related to inappropriate antidiuretic hormone secretion and/or renal tubulointerstitial disease impairing sodium reabsorption - Legionella is often diagnosed by urinary antigen testing; it grows on selective medium (*buffered charcoal yeast extract [BCYE]*).
Arise from uterine myometrium that occur due to monoclonal proliferation of myocytes and fibroblasts.
Leiomyoma (uterine fibroid) - Grossly, fibroids appear as discrete, yellow-gray tumors with a thin pseudocapsule that separates the fibroid from the normal uterine myometrium. - Diagnosis is confirmed with microscopy, which typically reveals monoclonal proliferation of myocytes and fibroblasts because each fibroid arises from a single progenitor smooth muscle cell. - Due to their benign nature, fibroid myocytes are uniform in size and shape and have minimal mitotic figures.
- Often presents with multiple discrete tumors - Increased incidence in *African Americans* - Benign smooth muscle tumor. - *Estrogen sensitive; tumor size increase with pregnancy and decrease with menopause* - Peak occurrence at 20-40 years of age. - May be asymptomatic, cause *abnormal uterine bleeding (heavy menses), pelvic pain, or result in miscarriage* - Severe bleeding may lead to iron deficiency anemia. - Whorled pattern of smooth muscle bundles with well- demarcated borders on histology.
Leiomyoma aka Uterine Fibroid - malignant transformation to leiomyosarcoma is rare - Grossly, fibroids appear as discrete, yellow-gray tumors with a thin pseudocapsule that separates the fibroid from the normal uterine myometrium. - Diagnosis is confirmed with microscopy, which typically reveals monoclonal proliferation of myocytes and fibroblasts because each fibroid arises from a single progenitor smooth muscle cell. - Due to their benign nature, fibroid myocytes are uniform in size and shape and have minimal mitotic figures. *Leiomyosarcoma* - Malignant smooth muscle tumor of uterus - Arise de novo (not from fibroids) - Occur in post-menopausal women - Usually a single large mass
- Usually in *postmenopausal women* - Exam shows single lesion with areas of necrosis - Malignant proliferation of smooth muscle arising from myometrium
Leiomyosarcoma - arises de novo (not from leiomyomas)
_______ is produced primarily by fat cells in response to short-term food intake and long-term adequacy of fat stores. It acts on the hypothalamus to decrease appetite (obesity blunts this action).
Leptin - During fasting states, leptin levels fall.
Specialized culture media can often identify the corkscrew-shaped organism. What is the organism?
Leptospirosis (motile spirochete)
Carcinogen: Alkylating agents Cancer: ???
Leukemia/lymphoma (blood) Exposure: oncologic chemotherapy
Do patients with LAD have leukopenia or leukocytosis?
Leukocytosis - Leukocyte adhesion deficiency is due to the absence of CD18 antigens, which are necessary for the formation of integrins. Failure of leukocyte adhesion and migration results in recurrent skin and mucosal infections *without purulence*, delayed umbilical cord separation, and peripheral leukocytosis.
_______ demonstrates a sawtooth infiltrate of lymphocytes at dermal-epidermal junction
Lichen planus - Pruritic, Purple, Polygonal Planar Papules and Plaques are the 6 P's of lichen Planus. - Mucosal involvement manifests as Wickham striae (reticular white lines) and hypergranulosis. - (CD8+) T cell-mediated response against cells along the dermal-epidermal junction
- Gain of function mutation--> decreased Na+ channel degradation --> increased Na+ reabsorption in collecting tubules - Metabolic alkalosis, hypokalemia, hypertension, decreased aldosterone
Liddle syndrome - autosomal dominant - Presents similarly to hyperaldosteronism, but aldosterone is nearly undetectable - Treatment: amiloride
Lesions affecting the cerebellar hemispheres cause
Limb dysmetria (overshoot/undershoot during targeted movement) - due to involvement of the lateral descending motor systems (eg, lateral corticospinal tract, rubrospinal tract). Hemispheric cerebellar lesions may also cause tremor during goal-directed activity (intention tremor).
______ histopathology shows well-differentiated, mature adipocytes with a fibrous capsule.
Lipoma
________ are common, benign tumors that arise from the subcutaneous fat and present as soft, mobile masses that are stable or enlarge slowly over time.
Lipomas - the epidermis is normal
Neisseria meningitidis can cause sepsis and circulatory collapse in previously healthy young individuals. ______ , a virulence factor in the pathogens outer membrane, is the major underlying cause of disease severity.
Lipooligosaccharide - The capsular polysaccharide of N meningitidis is an important virulence factor that helps the bacteria resist phagocytosis and complement activation. N meningitidis also releases IgA protease, which aids in nasopharyngeal epithelial colonization. However, these virulence factors are not the direct cause of meningococcal septic shock.
What are the rapid acting insulins?
Lispro, Aspart, Glulisine
Failure of neuronal migration resulting in a "smooth brain" that lacks sulci and gyri. May be associated with microcephaly, ventriculomegaly.
Lissencephaly
What organ is least susceptible to infarction? What is most susceptible?
Liver Brain - The presence of a dual and/or collateral blood supply (as seen in the liver, which is supplied by the hepatic artery and portal vein) enables an organ to tolerate arterial occlusion better than those with end-arterial circulations. Organ susceptibility to infarction after occlusion of a feeding artery is ranked from *greatest to least* as follows: - central nervous system, - myocardium, - kidney, - spleen - liver - Infarcts in an otherwise normal liver are rare because it has a dual blood supply: the portal vein and hepatic artery. Should the hepatic artery become occluded, the portal venous supply and retrograde arterial flow through accessory vessels (e.g., from the inferior phrenic, adrenal, intercostal arteries, etc.) is typically sufficient to sustain the liver parenchyma. - *The notable exception is when a transplanted liver undergoes hepatic artery thrombosis. In this case, the liver can develop biliary tree infarction and organ failure because the collateral blood supply is severed during transplantation*.
________ presents acutely with fever, right upper quadrant pain, jaundice, and eosinophilia.
Liver fluke infection - usually affects individuals from endemic areas (eg, Southeast Asia) - Infection of the biliary tree is associated with the formation of brown pigment gallstones
Nematode route of infection: bite
Loa Loa Onchocerca volvulus Wuchereria bancrofti "Lay LOW to avoid getting bit by them"
Decreased E-cadherin expression. No mass or calcifications --> incidental biopsy finding.
Lobular carcinoma in situ
___(low/high)____-calcium diets are associated with increased risk of stone formation.
Low - Dietary calcium binds oxalate in the gut to form unabsorbable calcium oxalate. Low-calcium diets lead to increased absorption of free oxalate, which is then excreted in the urine; the resulting hyperoxaluria promotes the formation of calcium oxalate stones. Low-calcium diets are therefore paradoxically associated with increased risk of stone formation.
Lab values in exogenous thyrotoxicosis:
Low: - TSH - radioactive iodine uptake - serum thyroglobulin (indicating suppression of endogenous thyroid activity) High - T4 and often T3
PPD skin test pathogenesis
M tuberculosis is primarily countered by the cell-mediated immune response (CMIR), previously infected patients have primed, antigen-specific *CD4 T lymphocytes* that rapidly replicate and mature in response to tuberculin antigen re-exposure. - T lymphocytes with specific T cell receptors recognize antigens presented on class II major histocompatibility complexes on the surface of dendritic cells (eg, antigen-presenting cells [APCs]) - A costimulatory interaction between CD28 on the T lymphocyte and CD80/86 on the dendritic cell then allows for activation - Activated CD4 T lymphocytes release inflammatory cytokines (eg, IL-1, IL-6, TNF alpha) that stimulate/recruit other immune cells and increase vascular permeability, forming an indurated wheal of inflammation following TST exposure. [Side note: CTLA-4 is inhibitory by binding to CD80/86 instead of CD28; PD-1 is also involved in terminating immune response]
MCC and location of osteomyelitis in children
MCC = Staph aureus Location = long bones - Osteomyelitis is an infection of bone and bone marrow that occurs by 1 of 3 mechanisms: 1. Hematogenous seeding due to an episode of bacteremia 2. Spread from a contiguous focus of infection, as occurs in an infected diabetic foot wound 3. Direct inoculation of bone, such as with a compound fracture - Hematogenous osteomyelitis occurs predominantly in children (particularly boys) and most frequently affects the long bones. The tibia, fibula, and femur are most often involved. Adults who develop the condition are more likely to have vertebral involvement and frequently have a predisposition to bacteremia due to risk factors such as IV drug abuse or indwelling vascular catheters. - The presenting symptoms of hematogenous osteomyelitis are vague, and a high index of suspicion is required to make the diagnosis. Initial symptoms such as malaise and fevers are non-specific. As the infection progresses, infants and younger children may refuse to move the affected extremity. Older children often complain of pain over a long bone. Bone pain develops as the abscess expands within the bone, leading to bone necrosis, periosteal disruption, and swelling of the surrounding soft tissue. - Staphylococcus aureus is implicated in most cases of acute hematogenous osteomyelitis in otherwise healthy children.
Gain of function of RET is seen in
MEN 2
Transporter associated with antigen processing (TAP) proteins are necessary for loading of cytoplasmic (eg, viral) proteins onto _________ molecules.
MHC 1 - Genetic mutations (eg, TAP1) affecting MHC class I-peptide complex expression (eg, bare lymphocyte syndrome type I) are rare but can cause ulcerative, granulomatous skin lesions and frequent respiratory infections despite normal lymphocyte and immunoglobulin levels.
What is the drug of choice for increasing HDL levels
Niacin - Adverese effects: Flushed face (via prostaglandin release; decreased by NSAIDs or long-term use); Hyperglycemia Hyperuricemia - Activates Gi --> decreases adenyl cyclase --> decrease cAMP
Which HIV drug binds CCR-5 on surface of T cells/monocytes, inhibiting interaction with gp120?
Maraviroc (essentially inhibits docking/entry)
fibrillin-1 gene mutation
Marfan's syndrome
The classic triad of findings for congenital rubella syndrome includes cataracts, sensorineural hearing loss, and patent ductus arteriosus. Prevention consists of ...
Maternal *preconception* immunization with the *live attenuated* rubella vaccine. - n contrast to killed vaccines that induce only humoral immunity, the rubella vaccine is a live attenuated vaccine and therefore induces both humoral and cell-mediated immunity. Vaccination should be administered prior to conception because live attenuated vaccines carry the potential risk of viral transmission to the fetus if given during pregnancy.
What is the effect of maternal hyperglycemia (ex: uncontrolled gestational diabetes) on the fetus/newborn?
Maternal hyperglycemia causes increased transplacental glucose delivery to the infant, fetal hyperglycemia, and, ultimately, *beta cell hyperplasia*. The resulting hyperinsulinemia caused by islet cell hyperplasia is associated with fetal macrosomia and hypoglycemia after delivery. - Chronic stimulation of the fetal beta cells leads to beta cell hyperplasia and hyperinsulinism. Elevated insulin levels contribute to increased fat deposition and enhanced fetal growth, resulting in macrosomia.
- Most common ovarian tumor in young females - Cystic mass with elements from all 3 germ layers (eg, teeth, hair, sebum) - May be painful 2 ̊ to ovarian enlargement or torsion - Monodermal form with thyroid tissue (struma ovarii) --> may present with *hyperthyroidism*. - Malignant transformation rare (usually to squamous cell carcinoma).
Mature Cystic Teratoma (benign) - Also called dermoid cyst. - germ cell tumor
_______ is due to Gs-activating [cAMP, adenyl cyclase] somatic *MOSAIC* mutation
McCune-Albright Syndrome
- Café-au-lait spots (unilateral), - Polyostotic fibrous dysplasia (multiple, unilateral osteolytic-appearing lesions of the hip and pelvis) - Precocious puberty (puberty < 8 yo) - Multiple endocrine abnormalities
McCune-Albright syndrome
examples of live attenuated vaccines
Measles, Mumps, Polio (sabin), Rubella, Varicella (herpes shingles), Yellow fever
Volar dislocation of the lunate from its normal position within the floor of the carpal tunnel can cause _______ nerve compression and/or injury.
Median - Median nerve injury at the level of the carpal tunnel may result in weakness of thumb abduction, flexion, and opposition.
_____ thyroid cancer appears histologically as polygonal or spindle-shaped cells with a slightly granular cytoplasm that stains for _____ .
Medullary calcitonin - Extracellular amyloid deposits consisting of calcitonin polypeptide may also be seen. - Medullary thyroid cancer is a component of multiple endocrine neoplasia types 2A and 2B.
- child - Homer Wright rosettes (groupings of cells surrounding the neuropil) - only in cerebellum - solid lesion can compress 4th ventricle --> hydrocephalus
Medulloblastoma
______ can spread via CSF and cause nodules in dura of spinal cord --> back pain, focal neuro deficits
Medulloblastoma
Diffuse capillary wall thickening on LM =
Membranous GN
"spike and dome" appearance of subepithelial deposits when stained with a silver stain =
Membranous nephropathy
_________ causes a nephrotic syndrome and is often associated with viral hepatitis, solid tumors, or lupus. LM reveals diffuse GBM thickening, which is due to the granular deposition of immune complexes (IgG and C3); EM demonstrates subepithelial deposits.
Membranous nephropathy
Uniform, diffuse capillary wall thickening is seen on light microscopy.
Membrenous nephropathy - In membranous nephropathy, which causes a nephrotic syndrome, immunofluorescence demonstrates granular deposits of IgG and C3 along the GBM
- Adults - psammoma body - arise from arachnoid cells - dural attachment - express *estrogen* receptors - prior radiation to head possible - often asymptomatic, possible *seizures*
Meningioma
Meninges (but no neural tissue) herniate through bony defect.
Meningocele - Neural Tube defects: Neuropores fail to fuse (4th week) --> persistent connection between amniotic cavity and spinal canal. Associated with maternal diabetes and folate deficiency. Increased α-fetoprotein (AFP) in amniotic fluid and maternal serum (except spina bifida occulta = normal AFP). Increased acetylcholinesterase (AChE) in amniotic fluid is a helpful confirmatory test.
________ stain positive for cytokeratins and many also stain positive for calretinin (immunohistochemistry)
Mesotheliomas - Non-smoking patient with dyspnea, cough, weight loss - Asbestos exposure is the primary risk factor; individuals with occupational exposure (eg, mining, shipbuilding, insulation installation) are at increased risk. - Mesothelioma is a neoplasm arising from mesothelial cells and is strongly associated with asbestos exposure. In early mesothelioma, multiple nodules form on the parietal pleura and gradually encase the lung parenchyma. Immunohistochemistry is important for diagnosis - Electron microscopy usually shows polygonal tumor cells with numerous long, slender microvilli and abundant tonofilaments.
Fanconi syndrome effects
Metabolic acidosis (proximal RTA) Hypophosphatemia Osteopenia
______- challenge testing is a highly sensitive but nonspecific measure that can help exclude a diagnosis of asthma
Methacholine
- Kidneys - Lungs - p-ANCA (myeloperoxidase antibodies)
Microscopic polyangitis
Aortic stenosis is loudest when?
Mid-murmur (half way between opening and closing)
_______ is a phosphodiesterase-3 inhibitor that reduces the degradation of cAMP
Milrinone 2 beneficial effects for treating systolic heart failure: - Calcium influx into cardiomyocytes is increased, which increases cardiac contractility - Calcium-myosin light chain kinase interaction is reduced, which causes vasodilation and reduces cardiac preload and afterload.
MOA of anthrax toxin in B anthrax
Mimics adenylate cyclase (increases cAMP) --> increased fluid secretion - Likely responsible for characteristic edematous borders of black eschar in cutaneous anthrax
Blastomyces dermatitidis location and manifestations
Mississippi and Ohio river vallies Immunocompetent hosts: pulmonary infection with *granulomatous* inflammation Immunocompromised host: extrapulmonary disease (skin, bone, genitourinary systems) - skin = grayish-white plaques
What murmurs increase in intensity in abrupt standing, nitroglycerine administration, or valsalva strain phase?
Mitral Valve Prolapse and HOCM [decrease preload and LV volume] [these 2 decrease in intensity with *squatting and passive leg raise*]
Presystolic murmur that disappears with afib
Mitral or tricuspid valve stenosis can cause a diastolic murmur with presystolic accentuation due to atrial contraction. With mild stenosis, the murmur may only be audible during the accentuation phase in late diastole; atrial fibrillation may cause the murmur to disappear completely.
________ is associated with IgM deposition in the glomerulus, leading to basement membrane thickening and cellular proliferation. Renal disease typically presents as membranoproliferative glomerulonephritis with hematuria and red blood cell casts. It is most common in patients with chronic hepatitis C infection.
Mixed cryoglobulinemia
_____ direct attachment of the placental villi onto the myometrium, typically presents after delivery of the fetus with postpartum hemorrhage and inability to remove the placenta.
Placenta accreta
______ is a form of arteriosclerosis characterized by calcific deposits in the medial layer of muscular arteries.
Monckeberg sclerosis (medial calcific sclerosis) - These lesions generally occur in patients age >50 and are thought to cause isolated systolic hypertension due to arterial hardening.
What is the first step in converting acyclovir to its active form?
Monophosphorylation of acyclovir (a guanosine analogue) by a viral* thymidine kinase is the first (and rate-limiting) step in conversion of acyclovir to its active triphosphate form. - The drug will impair viral DNA-polymerase mediated replication of HSV
Polysaccharides must be degraded to monosaccharides by pancreatic and brush border amylases before they can be absorbed. _________ , such as __________ , can be absorbed directly.
Monosaccharides Galactose, Glucose, D-xylose - D-xylose is a monosaccharide whose absorption is not affected by exocrine pancreatic insufficiency, and can be used to differentiate between pancreatic versus mucosal causes of malabsorption. - The stool neutral fat (triglyceride) content is increased after pancreatic resection due to deficiency of pancreatic lipase.
acute tubular necrosis
Most common cause of acute kidney injury in hospitalized patients. Spontaneously resolves in many cases. Can be fatal, especially during initial oliguric phase. IncreasedFENa. Key finding: granular casts (often muddy brown in appearance). 3 stages: 1. Inciting event 2. Maintenance phase—oliguric; lasts 1-3 weeks; risk of hyperkalemia, metabolic acidosis, uremia 3. Recovery phase—polyuric; BUN and serum creatinine fall; risk of hypokalemia and renal wasting of other electrolytes and minerals. Can be caused by ischemic or nephrotoxic injury: - Ischemic—2° to decreased renal blood flow (eg, hypotension, shock, sepsis, hemorrhage, HF). *Results in death of tubular cells that may slough into tubular lumen B (PCT and thick ascending limb are highly susceptible to injury).* - Nephrotoxic—2° to injury resulting from toxic substances (eg, aminoglycosides, *radiocontrast agents*, lead, cisplatin, ethylene glycol), crush injury (myoglobinuria), hemoglobinuria. *Proximal tubules are particularly susceptible to injury.*
In hemolytic disease of the newborn, is the mother Rh-positive or negative? What about the baby? What kind of HS rxn is it?
Mother = Rh-negative Baby = Rh-positive Type 2 HS rxn (like acute hemolytic transfusion rxns) - Rhesus (Rh) antigens are a group of nonglycosylated, transmembrane proteins found on the surface of red blood cells. The D antigen is the most immunogenic of the group and is present on the erythrocytes of Rh-positive individuals. When an Rh-negative mother becomes pregnant with an Rh-positive fetus, fetal red blood cells can enter the maternal circulation and elicit a maternal antibody response with the formation of memory B lymphocytes (Rh alloimmunization). After Rh alloimmunization occurs, subsequent pregnancies with Rh-positive fetuses will be at risk for hemolytic disease of the newborn. - To avoid maternal Rh alloimmunization, Rh-negative mothers must be prevented from mounting an immune response against the D antigen. Anti-Rh(D) immunoglobulin is a polyclonal antibody product consisting of IgG anti-D antibodies collected from pooled donor plasma. It is administered to Rh-negative women during gestation and in the immediate postpartum period. Once given, anti-Rh(D) antibodies bind to Rh-positive fetal erythrocytes that enter the maternal circulation, preventing their interaction with the maternal immune system by promoting sequestration and elimination in the mother's spleen (ie, the mononuclear phagocyte system). - Although IgG antibodies can cross the placenta, anti-Rh(D) IgG antibodies do not cause significant transplacental fetal hemolysis because the amount of antibody administered is negligible compared with the amount produced in a typical immune hemolytic reaction.
- Rare - May be metastatic from appendiceal or GI tumors - Can result in pseudomyxoma peritonei (intraperitoneal accumulation of mucinous material).
Mucinous cystadenocarcinoma
______ species infect the paranasal sinuses in patients with neutropenia, burns, or diabetes mellitus.
Mucor - Mucormycosis is strongly associated with diabetic ketoacidosis.
- Hypercalcemia - Renal insufficiency - Anemia (low hemoglobin) - Bone lytic lesions (radiolucent [appear dark] on x-ray)
Multiple Myeloma - elevated protein levels too maybe - Multiple myeloma is a plasma cell malignancy associated with purely radiolucent (osteolytic) bone lesions due to the stimulation of osteoclasts and the inhibition of osteoblasts. Myeloma cells stimulate osteoclast development by secreting RANK-ligand and destroying osteoprotegerin, which increases RANK activity and results in osteoclast differentiation. Multiple myemoma cells also uniquely inhibit osteoblast activity by secreting cytokines that block osteoblast function (eg, IL-3, IL-7, Wnt pathway inhibitors). - *Decreased Vit D and PTH levels [PTH-related protein levels = normal]* ; *contrast*: granulomatous disease (sarcoidosis, TB) cause increased Ca via increased vit D [which causes suppressed PTH]
_____ inhibits lipolysis (hormone- sensitive lipase) in adipose tissue; reduces hepatic VLDL synthesis
Niacin - also raises HDL levels - Adverese effects: Flushed face (via prostaglandin release; decreased by NSAIDs or long-term use); Hyperglycemia Hyperuricemia
Promotion of intracellular survival is accomplished by inhibition of phagosome-lysosome fusion or resistance to lysosomal enzymes. These properties are expressed by
Mycobacterium tuberculosis, M leprae, Legionella, and Ehrlichia.
_______ binds an oligosaccharide on the respiratory epithelium that is also present on erythrocytes, leading to the generation of cross-reacting IgM antibodies (cold agglutinins). Patients often develop mild, transient *hemolytic anemia* that resolves as IgM antibody titers decline (6-8 weeks after infection begins).
Mycoplasma pneumoniae
Meninges and neural tissue (eg, cauda equina) herniate through bony defect.
Myelomeningocele - Neural Tube defects: Neuropores fail to fuse (4th week) --> persistent connection between amniotic cavity and spinal canal. Associated with maternal diabetes and folate deficiency. Increased α-fetoprotein (AFP) in amniotic fluid and maternal serum (except spina bifida occulta = normal AFP). Increased acetylcholinesterase (AChE) in amniotic fluid is a helpful confirmatory test.
Exposed, unfused neural tissue without skin/meningeal covering.
Myeloschisis - Also called rachischisis. - Neural Tube defects: Neuropores fail to fuse (4th week) --> persistent connection between amniotic cavity and spinal canal. Associated with maternal diabetes and folate deficiency. Increased α-fetoprotein (AFP) in amniotic fluid and maternal serum (except spina bifida occulta = normal AFP). Increased acetylcholinesterase (AChE) in amniotic fluid is a helpful confirmatory test.
_______ is a refractive error in which the focal point of an image falls anterior to the retina due to an increased anterior-posterior diameter of the eyes.
Myopia (nearsightedness) - Patients have difficulty seeing objects at a distance and have normal near vision.
Von Recklinghausen's disease is another name for
NF1
Conn's Syndrome (Primary Hyperaldosteronism) Lab values:
Na: Normal (equalizes out eventually due to aldosterone escape [excess volume from aldosterone causes increased renal blood flow and ANP to be released --> natriuresis]) K+: Low H+ : Low HCO3- : High (Pt is in metabolic Alkalosis) - Primary hyperaldosteronism causes increased Na+ reabsorption in the renal collecting tubules, leading to increased urinary excretion of K+ and H+. Patients typically have secondary hypertension as well as hypokalemia and metabolic alkalosis. The serum Na+ concentration remains normal due to aldosterone escape.
Primary amebic meningoencephalitis (PAM) is caused by _________ , a free-living, motile, protozoan parasite that lives in warm water and soil worldwide. Exposure primarily occurs when humans inadvertently inhale the organism during recreational water activities such as swimming, diving, or using hot springs.
Naegleria fowleri - Characterized by acute fever, headache, confusion, and neck stiffness. - Suspicion is usually raised when CSF testing is negative for bacterial, viral, or fungal pathogens. - The diagnosis is confirmed when wet mount of the CSF reveals motile trophozoites. - Antibiotics (eg, amphotericin B) are often administered, but PAM is almost always fatal. - Lumbar puncture opening pressures are often markedly elevated, and CSF analysis typically reveals neutrophilic pleocytosis, high protein, and low glucose.
______- is a first-line pharmacotherapy for moderate-to-severe alcohol use disorder, and works by preventing the reinforcing effects of alcohol use.
Naltrexone (Mu opioid antagonist )
Human hookworm infection is caused by
Necator americanus and Ancylostoma duodenale. - Most cases occur in tropical and subtropical regions where sanitation is poor. Transmission occurs when egg-containing human feces is deposited into shady, warm, moist soil, which allows the eggs to hatch into larvae. Spread occurs when larvae come into direct contact with human skin (eg, when walking barefoot). - Dermal penetration often results in a transient, pruritic, maculopapular or serpiginous rash at the entry site. The larvae then spread through the bloodstream to the lungs, where they rupture into the alveoli and are subsequently coughed up and swallowed. - In the small intestine, the larvae mature into adults, attach to the gastrointestinal mucosa, and feed on human blood by lacerating capillaries. Because these organisms can live in the gastrointestinal tract for up to 14 years, total blood loss can be substantial. Therefore, the biggest risk of hookworm infection is iron-deficiency anemia (microcytic anemia) due to chronic blood loss. - Although many patients with hookworm infection are asymptomatic for months or years, some individuals develop transient pulmonary symptoms (eg, cough) during pulmonary migration or gastrointestinal symptoms (eg, nausea, vomiting, diarrhea) during gastrointestinal migration. - Diagnosis is generally made when smooth, thin-walled hookworm eggs are identified by stool microscopy. Peripheral eosinophilia is also an important diagnostic clue.
Is Staph epidermidis *coagulase* positive or negative?
Negative (it does have catalase though)
triad of arthritis, dermatitis, and tenosynovitis in a sexually active woman is likely due to
Neisseria gonorrhoeae
Patients with disseminated __________ disease typically present with the triad of polyarthralgia, tenosynovitis, and dermatitis or purulent arthritis.
Neisseria gonorrhoeae - diagnosis is confirmed when the organism is isolated on Thayer-Martin media, chocolate agar infused with antibiotics.
IgA protease is produced by __________ . This enzyme cleaves secretory IgA at its hinge region, rendering it ineffective. Secretory IgA exists on mucosal surfaces and in secretions and acts to bind and inhibit the action of pili as well as other cell surface antigens that normally mediate mucosal adherence and subsequent penetration.
Neisseria meningitidis, N gonorrhoeae, Streptococcus pneumoniae, and Haemophilus influenzae
- abdominal mass - elevated catecholamine breakdown products - small round blue cells + Homer Wright Rosettes (like medulloblastoma) - multi-directional eye movements (opsoclonus), quick, involuntary muscle jerks (myoclonus),
Neuroblastoma
_________ is a common cause of adult-onset seizures in patients from rural developing regions. Suspicion should be raised when brain imaging in these individuals shows cystic or calcified lesions.
Neurocysticercosis - transmitted via infected stool - Taenia solium (pork tapeworm) eggs
Displaced point of apical impulse is a sign of decompensated HF. What will this cause?
Neuroendocrine compensatory mechanisms in an effort to restore organ perfusion: - Increased sympathetic output: Baroreceptors sense decreased perfusion and stimulate epinephrine and norepinephrine release to increase heart rate and contractility. Vasoconstriction is also triggered, increasing arteriolar resistance and raising afterload. - Renin-angiotensin-aldosterone system (RAAS) activation: *Decreased renal perfusion* leads to increased secretion of renin and increased circulating levels of angiotensin II, a potent vasoconstrictor that further increases afterload. Adrenal secretion of aldosterone also increases, which stimulates sodium and water retention and increases circulating blood volume (preload).
_______ is due to mutations that inactivate the merlin tumor suppressor protein.
Neurofibromatosis type 2
_______ are involved in the posttranslational processing and stabilization of oxytocin and vasopressin within neurosecretory vesicles during transport *to* the posterior pituitary.
Neurophysins
In ARDS, the inflammation is driven by what leukocyte?
Neutrophils - Acute respiratory distress syndrome involves acute *neutrophilic* lung inflammation with widespread alveolar damage due to *proteases and reactive oxygen species*, leading to *failure of the vascular barrier and exudative pulmonary edema*.
Does ductal carcinoma in situ produce a mass?
No Contrast: Invasive ductal carcinoma - Firm, fibrous, "rock-hard" mass with sharp margins and small, glandular, duct-like cells in desmoplastic stroma.
Hypercalciuria is the number 1 reason for calcium kidneys stones. But are the blood calcium levels high too?
No, the blood calcium levels are usually normal because they are maintained by vit D and PTH - Hypercalciuria is the most common risk factor for calcium (calcium oxalate and calcium phosphate) kidney stones in adults; contributing factors may include increased gastrointestinal absorption, increased mobilization of calcium from bone, or decreased renal tubular calcium reabsorption. However, most patients remain normocalcemic due to regulation of plasma calcium levels by vitamin D and parathyroid hormone. - Hyperuricosuria with hyperuricemia can occur with myeloproliferative disorders, tumor lysis syndrome, gout, and Lesch-Nyhan syndrome. - High-protein diets typically cause hyperuricosuria with normouricemia. - Hyperuricosuria can cause uric acid stone formation and also predisposes to calcium nephrolithiasis (uric acid precipitation acts as a nidus for calcium deposition). - Hyperoxaluria can result from a diet high in oxalate (found in foods such as chocolate, nuts, and spinach). Low-calcium diets and intestinal malabsorption syndromes such as *Crohn disease* can also cause hyperoxaluria as both cause less calcium to be available to bind and trap oxalate in the gut. Hyperoxaluria is a less common risk factor for calcium stone formation than hypercalciuria.
Do contraceptives cause acne?
No, they often decrease the risk for acne because they lower androgen levels [tight fitting sports clothing can cause acne]
In case lumbar puncture can't be performed, what test can be used?
Non-contrast CT - if that is negative, do a lumbar puncture anyway? [def *won't* do MRI though because redundancy]
Which anti-HTN drug causes constipation?
Non-dihydropyridine CCBs (Verapimil, Diltiazem) AE: - Dihydropyridine: peripheral edema, flushing, dizziness. - Non-dihydropyridine: cardiac depression, AV block, hyperprolactinemia (verapamil), constipation.
Becker muscular dystrophy type of mutation
Non-frameshift
Protective equipment for patient with C diff
Non-sterol gloves and a gown
________ sleep apnea is due to relaxation of oropharyngeal muscle tone with occlusion of the upper airway.
Obstructive - Symptoms include daytime sleepiness, *headaches*, and *depression*. - Complications include systemic and pulmonary hypertension, right heart failure, and an increased risk for cardiac events.
______ apnea, the most common sleep-related breathing disorder, is characterized by recurrent obstruction of the upper airways. Relaxation of the oropharyngeal and/or soft palate musculature during sleep results in a functional collapse of the airway, producing periods of reduced (hypopnea) or absent (apnea) airflow despite continued breathing efforts.
Obstructive sleep - Patients may not be aware of apnea, but bed partners commonly report loud snoring with intermittent episodes of silence. This pattern occurs hundreds of times per night, leading to poor sleep quality and chronic fatigue. Risk factors for OSA include obesity, large neck circumference, and reduced oropharyngeal diameter (eg, enlarged tonsils or tongue, retro- or micrognathia).
- Adults - calcified, well-circumscribed mass in FRONTAL LOBE - uniform cells with fried egg appearance
Oligodendroglioma
Treatment for pseudomonas aeruginosa
Only a few specific penicillins (eg, ticarcillin, piperacillin) and cephalosporins (eg, ceftazidime, cefepime) have activity against it. Certain aminoglycosides, fluoroquinolones (eg, ciprofloxacin, levofloxacin), and carbapenems (eg, imipenem, meropenem) are also effective.
If untreated, Giant Cell Arteritis/Temporal Arteritis can cause blindness due to...
Ophthalmic artery occlusion (ischemic optic neuropathy)
_________ is a behavioral disorder of childhood characterized by argumentative and defiant behavior toward authority figures. It does not involve the more severe violations of the basic rights of others seen in conduct disorder.
Oppositional defiant disorder
______ involves a pattern of angry/irritable mood and argumentative/defiant behavior toward authority figures, but does not include physical aggression, stealing, or destruction of property, etc.
Oppositional defiant disorder (ODD)
- autosomal dominant mutations of genes involved in angiogenesis (eg, ENG, ACVRL1) - mucocutaneous telangiectasias, - epistaxis, - visceral arteriovenous malformations (AVMs) (eg, liver, lung, brain). Lung involvement includes: - pulmonary AVMs (eg, digital clubbing, platypnea) - pulmonary hypertension (eg, a loud P2) [due to high-output heart failure from underlying systemic AVMs]
Osler-Weber-Rendu syndrome (hereditary hemorrhagic telangiectasia) presence of telangiectasias --> rupture of these telangiectasias may cause epistaxis, gastrointestinal bleeding, or hematuria.
______ is a small, benign, bone-forming tumor that typically occurs in adolescent boys. Histopathology shows irregular patterns of woven bone lined by a single layer of benign-appearing osteoblasts.
Osteoid osteoma
Is passive range of motion normal in osteomyelitis or septic arthritis?
Osteomyelitis
Chronic hip pain that is worse with weight bearing and decreased range of motion in multiple axes. X-ray reveals flattening and patchy sclerosis of the femoral head consistent with ____
Osteonecrosis (avascular necrosis)
- Males < 20 yo (also in elderly, but less common and Secondary) - Metaphysis of long bones (often in knee region) - Slowly worsening pain + soft tissue swelling - X-ray: a lytic bone lesion - Biopsy: pleomorphic, spindle-shaped tumor cells that generate osteoid and thin trabeculae of neoplastic bone.
Osteosarcoma Molecular Pathology: - Rb gene (chromosome 13): sporadic and inherited retinoblastoma - P53: sporadic and Li Fraumeni syndrome - CDKN2a, CDK4, and MDM2: sporadic Characteristics: - Pleomorphic osteoid-producing cells (malignant osteoblasts). - Presents as painful enlarging mass or pathologic fractures. - Codman triangle (from elevation of periosteum) or sunburst pattern on x-ray (think of an osteocod (bone fish) swimming in the sun). - Aggressive. 1° usually responsive to treatment (surgery, chemotherapy), poor prognosis for 2°.
________ histopathology shows pleomorphic malignant cells with hyperchromatic nuclei forming neoplastic osteoid or bone
Osteosarcoma [excess production of mineralized bone]
Ear pain Fever Bulging or ruptured TM with purulence in middle ear
Otitis media Caused by: S pneumoniae H influenza (non-typeable)* Moraxella cataralis - nontypeable strains do not form a polysaccharide capsule, immunity is not conferred by vaccination with the H influenzae type b vaccine. - Vaccination against H influenzae is with the protein-conjugated Hib vaccine, which confers immunity only to the more invasive type b strain. The vaccine is recommended in all children to prevent Hib-associated bacteremia, pneumonia, epiglottitis, and meningitis.
What cancers have a transcoelemic spread (spread throughout a body cavity)?
Ovarian tumor --> surface of the liver
Tumor Marker: CA125 Associations: ???
Ovarian tumor/cancer - It may also be elevated in other malignancies (eg, endometrial) and certain benign conditions (eg, endometriosis).
_______ incontinence = Incomplete emptying (detrusor underactivity or outlet obstruction)--> leak with overfilling, increased post-void residual on catheterization or ultrasound. This is seen in which conditions?
Overflow - Polyuria (Diabetes) - Bladder outlet obstruction (BPH) - Neurogenic bladder (MS)
_______ refers to provision of services that are not expected to improve patient outcomes or meaningfully change management. Patient-centered health care requires care to be delivered with respect to patients' concerns, preferences, and priorities, but does not require unnecessary testing or treatment if patient input is otherwise solicited and respected when appropriate.
Overutilization
What strains of malaria have a dormant hepatic phase (hypnozoite) that may reactivate several months after return from an endemic region (if not treated with primaquine)?
P ovale and P vivax - In contrast, P falciparum does not have a dormant hepatic phase; it matures in (and is released from) the liver over 8-30 days.
SCC of skin is associated with what mutations?
P53 (CDKN2A less frequently)
______ presents with weeks or months of nonspecific constitutional symptoms (eg, weight loss, fatigue, low-grade fever, arthralgias) and signs of tissue ischemia in the kidneys (eg, renal infarction), gastrointestinal tract (eg, small-bowel infarction, mesenteric ischemia), peripheral nerves, and/or skin.
PAN - associated with Hep B - Spares the lungs - Segmental, transmural inflammation of the medium sized muscular arterial wall with invasion of neutrophils and monocytes
SKIN NODULES Neuropathy is usually not bilateral Lungs are spared GI pain (melena is possible) Ex: problems with gall bladder
PAN - type 3 HS - Associated with Hep B - spares lungs - Rosary sign; can lead to aneurysm and constrictions
In tetralogy of fallot, if pulmonary stenosis is severe, the patient will require __________ to survive
PDA - a structure that connects the Pulmonary artery to the Aorta [normally maintained in utero by circulating prostaglandin; can maintain after birth via Prostaglandin E1 administration]
blood supply to lateral part of medulla
PICA
Granular deposits of IgG and C3 along GBM =
PSGN
basal cell carcinoma is associated with what mutations
PTCH and P53
_____ causes bone formation (by direct effect on osteoblasts) and bone resorption (by *paracrine* effect on osteoclasts).
PTH - Bone turnover is normally balanced, with bone formation proportionate to resorption. - In hyperparathyroid states, continuous exposure to high PTH levels cause increased RANK-L expression along with suppression of osteoprotegerin (a counterregulatory decoy receptor). This leads to *greater bone resorption* than formation and net bone loss.
_____ is characterized by excessive and disordered bone formation, with focal *thickening of trabecular and cortical bone*. Features include bone pain, fractures, and arthritis of adjacent joints.
Paget disease of the bone [Osteoclastic--> mixed --> osteoblastic phase (jigsaw puzzle)] - commonly affects the skull, long bones, and vertebral column - Normal Ca, PO, and PTH, but *ELEVATED Alkaline Phosphatase [due to increase in new bone formation]*
Pain in arm/shoulder + cough/hemoptysis =
Pancoast tumor - Also, Horner Syndrome, muscle atrophy in arm, upper extremity edema, etc.
Superior sulcus tumor =
Pancoast tumor - arise at the lung apex and can also cause SVC syndrome. However, shoulder pain is typically present due to tumor invasion into the brachial plexus or nearby chest wall. Horner syndrome (ptosis, miosis, and anhidrosis) also is common due to cervical sympathetic ganglia involvement. Neurologic deficits (eg, hand weakness) also can occur.
symptoms in MEN 1 (Wermer's syndrome)
Pancreatic Adenoma Pituitary Adenoma Parathyroid Adenoma
What is the most common pancreatic malignancy?
Pancreatic ductal adenocarcinoma - typically presents with epigastric pain, weight loss, jaundice (more common if in the pancreatic head), or back pain (more common if in the pancreatic body/tail). - It appears radiographically as an ill-defined hypoattenuating lesion within the pancreatic parenchyma. - It is characterized microscopically by haphazardly arranged pleomorphic glandular cells surrounded by dense stromal fibrosis (eg, desmoplasia).
Tumor Marker: CA 19-9 Associations: ???
Pancreatic tumor
Caput Medusa [dilated superficial epigastric veins around the umbilicus] involves which blood supply?
Para-umbilical veins (portal system) + Superficial epigastric vein (superior and inferior epigastric vein)
Fungi in Central and South America - clinical presentation: Mucocutaneous: chronic mucocutaneous or cutaneous ulcers, can progress to lymph nodes and lungs
Paracoccidioides brasiliensis - clinical presentation: Mucocutaneous: chronic mucocutaneous or cutaneous ulcers, can progress to lymph nodes and lungs - Lab dx: Culture (25ºC): multiple blastoconidia. Biopsy: cells covered in budding blastoconidia
Oxytocin is secreted by what part of the hypothalamus
Paraventricular nucleus (later stored in the post pituitary)
Cardiac autonomic neuropathy, which can develop in patients with ________ , typically leads to an impaired sympathetic cardiac response. This often results in exercise intolerance and orthostasis but does not significantly contribute to cardiac arrhythmia.
Parkinson disease or poorly controlled diabetes mellitus
_________ is a single-stranded DNA virus that infects and destroys erythroid progenitor cells and can result in fetal hydrops when the infection is contracted during pregnancy.
Parvovirus B19
_______ can mimic rheumatoid arthritis but is usually self-resolving.
Parvovirus arthritis - Parvovirus B19 = non-enveloped, linear ssDNA - Erythema infectiosum (fifth disease), found primarily in children: This disease manifests as a bright red rash on the cheeks with circumoral pallor and fever. Patients may also have a generalized reticular rash on the arms, legs, and trunk. - Acute arthropathy, found primarily in adults: This symmetric polyarthritis involves the proximal interphalangeal, metacarpal, knee, and ankle joints. The arthritis is self-limited and nondestructive.
_______ is a cause of soft-tissue infection that develops within 24 hours following a dog or cat bite.
Pasteurella multocida - "mouse like odor"
Regarding Pemphigus vulgaris and Bullous pemphigoid, which is itchy and which is painful?
Pemphigus vulgaris = painful - 40-60 yo Bullous pemphigoid = itchy - +60 yo
______ sense changes in carbon dioxide, oxygen, and pH levels and trigger the _______ to modify respiration.
Peripheral chemoreceptors (eg, carotid bodies, aortic body) central respiratory center
Prostate cancer is in what zones and lobes?
Peripheral zone and posterior zone
In B pertussis, __________ an AB toxin that enters cells and activates adenylate cyclase, leading to alterations in cellular signaling that *inhibit phagocyte activity* and can cause lymphocytosis.
Pertussis toxin
_______ refers to coinfection of a host cell by 2 viral strains, resulting in progeny virions that contain nucleocapsid proteins from one strain and the unchanged parental genome of the other strain.
Phenotypic mixing - Because there is no change in the underlying viral genomes (no genetic exchange), the next generation of virions revert to their original, unmixed phenotypes.
___________ is an irreversible α1 and α2 receptor antagonist and is primarily used in the treatment of pheochromocytoma
Phenoxybenzamine
_________ is a reversible, competitive α-adrenergic antagonist used in the management of catecholamine-induced hypertensive crises (eg, pheochromocytoma, monoamine oxidase inhibitor toxicity, cocaine intoxication)
Phentolamine
What disorder arises from Adrenal MEDULLARY (not cortical) hyperplasia?
Pheochromocytoma
Microscopic examination of the ________ tumor cells shows electron-dense, membrane-bound secretory granules, and immunohistochemistry is positive for synaptophysin, chromogranin, and neuron-specific enolase.
Pheochromocytoma - Histopathology shows a highly vascular tumor with nests of spindle-shaped or polygonal cells
______ is a tumor arising from the chromaffin cells of the adrenal medulla
Pheochromocytoma - characterized by excess production of catecholamines. - Clinical features include episodic hypertension, diaphoresis, and palpitations.
Pressure ([possibly episodic] increased BP) Pain (episodic headache) Perspiration Palpitations (tachycardia) Pallor Anxiety Excessive sweating (excessive diaphoresis) Cardiac arrhythmias Feeling of impending doom
Pheochromocytoma - Adrenal medulla tumor in adults - from chromaffin cells (which comes from neural crest cells) - because Dopamine, NE, and E --> stains with silver stain
______ are blood-sucking lice that cause INTENSE PRURITIS with associated excoriations - commonly on scalp and neck (head lice), waistband and axilla (body lice), or pubic and perianal regions (pubic lice).
Phthirus pubis - condoms DON'T prevent transmission
Stress-related mucosal disease is usually caused by local ischemia in the setting of severe ________ . Ulcers arising in the setting of severe trauma/burns are called _____ ulcers. Ulcers arising from intracranial injury are caused by direct vagal stimulation and are called ______ ulcers.
Physiologic stress (eg, shock, extensive burns, sepsis, severe trauma) Curling Cushing
_____ is the compulsive consumption of a non-nutritive and/or nonstaple food.
Pica - ex: ice, dirt It is common in pregnancy and is often associated with iron deficiency anemia and other forms of nutritional deficiency.
- child - posterior fossa (ex: cerebellum) - cystic and solid components on imaging - Rosenthal fibers - GFAP positive
Pilocytic astrocytoma - Glioblastoma, etc. are GFAP positive too - Medulloblastoma only has solid (no cystic) component
Dx Cushing Syndrome: - ACTH: Normal/Elevated - High Dose Dexamethasone Test: Suppression of ACTH and Cortisol levels
Pituitary Adenoma Excess ACTH secretion causes identifiable clinical findings: - Hyperpigmentation: Both ACTH and alpha-melanocyte-stimulating hormone (MSH) are derived from pro-opiomelanocortin, leading to cosecretion of alpha-MSH. ACTH also directly stimulates the MC2R receptor on melanocytes. - Androgenization: ACTH stimulates production of adrenal androgens (eg, ↑DHEAS [dehydroepiandrosterone sulfate], androstenedione). This leads to hirsutism, menstrual abnormalities, and oily skin.
CD4 count < 200
Pneumocystis Jerovicii (PCP) - pneumocystis pneumonia --> ground glass opacities on chest imaging Histoplasmosis - oval yeast cells within macrophages - fever, weight loss, fatigue, cough, dyspnea, nausea, vomiting, diarrhea Coccidioidomycosis Progressive Multifocal Leukoencephalopathy (PML) -JC virus - non-enhancing areas of demyelination of MRI HIV dementia (cerebral atrophy on neuroimaging)
Co-trimoxazole is the DOC for
Pneumocystis jiroveci, Toxoplasma gondii, Nocardia, Stenotrophomonas maltophilia
Histopathologic and cytologic findings in _______ include eosinophilic foamy alveolar material and cystic and trophic forms that can be stained with Giemsa or silver stain (producing a cup-in-saucer appearance).
Pneumocystis jirovecii pneumonia (PCP) - In addition, PCP is more common in patients with advanced HIV than in transplant patients and would be unlikely in this patient on PCP prophylaxis with trimethoprim-sulfamethoxazole.
- Decreased or absent breath sounds - Decreased tactile fremitus - Hyperresonance to percussion
Pneumothorax - Traumatic pneumothorax: can involve puncture of either the chest wall (eg, penetrating chest trauma) or the lung (eg, by fractured ribs), allowing air to enter the pleural space. Disruption of the skin or parietal pleura during the initial injury often allows air to enter the subcutaneous tissues of the chest wall, which is detected as *subcutaneous crepitus* (ie, crackling during palpation) - *Contrast*: Dullness to percussion over the chest is expected with conditions that cause increased density (eg, hemothorax, pleural effusion, alveolar consolidation) compared to normal lung tissue. - Tactile fremitus represents airway vibrations generated by vocalized sound (eg, saying "ninety-nine") and is measured by the examiner placing hands on the patient's back. Because air in the chest cavity insulates and dampens airway vibrations before they reach the patient's back, decreased tactile fremitus is expected. - Breath sounds are caused by air movement within the airways, and the intensity varies by lung location. Vesicular breath sounds are normal over the periphery; bronchial breath sounds are higher-intensity sounds that are normal over the hilum but indicate pathology (eg, lobar consolidation) over the periphery. Because the lung is partially collapsed, leading to less air movement, decreased breath sound intensity is expected. - Resonance refers to the frequency of sound generated by percussion, and it varies with density. Because air alone is less dense than a composite of lung parenchyma and air (ie, normal lung), higher-than-normal sound frequency to percussion (ie, hyperresonance) is expected.
- Dyspnea, - uneven chest expansion. - Chest pain, - decreased tactile fremitus - hyperresonance, - diminished breath sounds - ALL ON THE EFFECTED SIDE
Pneumothorax - accumulation of air in the pleural space
________ plans require patients to have a primary care provider and obtain referrals for specialty consultations. They differ from HMO plans in that they allow patients to see providers outside the network, albeit at higher out-of-pocket costs (copays and deductibles).
Point-of-service
________ plans require patients to have a primary care provider and obtain referrals for specialty consultations. However, patients may also see out-of-network providers.
Point-of-service (POS) - POS plans typically have higher premiums than HMOs and significant costs if patients choose to see out-of-network specialists.
- Progressive symmetric proximal muscle weakness, - endomysial inflammation with CD8+ T cells. - Most often involves shoulders.
Polymyositis
Sub-epithelial humps on EM=
Post-Strep GN
In _________ , LM demonstrates hypercellular glomeruli, whereas IF shows a "lumpy-bumpy" pattern of granular IgG and C3 deposition on the GBM. EM also demonstrates subepithelial immune complex deposits.
Poststreptococcal glomerulonephritis
_______ plans usually offer the most flexible choices for both in-network and out-of-network providers.
Preferred provider organization (PPO) - However, PPOs typically have higher premiums and deductibles than HMO plans.
Pregnancy is a pro-thrombotic or anti-thrombotic state?
Pregnancy is a prothrombotic state due to increased procoagulant factors (eg, fibrinogen), decreased anticoagulant factors (eg, protein S), and reduced fibrinolysis. These physiologic changes protect against maternal hemorrhage with delivery but increase the risk of peripartum venous thromboembolism. - Increased procoagulant factors: coagulation factors involved in the intrinsic (eg, factor XII), extrinsic (eg, factor VII), and final common (eg, fibrinogen) pathways of clotting are increased by up to 200%, which promotes the formation of cross-linked fibrin clots. - Decreased anticoagulant factors: protein S levels decrease and resistance to activated protein C increases, leading to reduced clotting factor proteolysis. - Reduced fibrinolysis: activity of fibrinolytic inhibitors (eg, plasminogen activator inhibitor-1 derived from the placenta) increases significantly, which reduces the breakdown of fibrin clots.
______ is a nonrefractive error that increases with age due to the *loss of accommodating power of the lens from decreased elasticity.*
Presbyopia - Blurry vision of nearby objects typically develops in patients age >40
!!! DPP-4 (-glips) inhibitors MOA
Prevent GLP-1 degradation --> decrease glucagon release --> increase glucose dependent insulin secretion
What is the MOA of ezetimibe?
Prevents cholesterol absorption at the SI brush border - decreases: LDL and TG (fibrates best for lowering TG; Statin best for LDL) - increases: HDL (slightly) (Niacin best for this)
_______ is associated with IgG4 antibodies to the phospholipase A2 receptor, which might play a role in development of the disease. Antibody titers are useful for diagnosis and correlate with disease activity.
Primary (idiopathic) Membranous nephropathy
- Single, painless genital ulcer with a clean base and raised indurated margins - enlarged inguinal lymph nodes
Primary syphillis
Preeclampsia is new-onset hypertension (systolic ≥140 mm Hg or diastolic ≥90 mm Hg) with proteinuria and/or signs of end-organ damage (eg, renal insufficiency). Preeclampsia is associated with widespread maternal endothelial dysfunction, which occurs due to increased antiangiogenic factor release and decreased ________
Proangiogenic factor activity (eg, vascular endothelial growth factor). - Endothelin and thromboxane A2 (TXA2) are potent vasoconstrictors. Therefore, their activity is typically increased, not decreased, in preeclampsia due to increased endothelin and TXA2 production by dysfunctional endothelial cells. - In patients who develop preeclampsia, early cytotrophoblast invasion is abnormal; as a result, the maternal spiral arteries that supply blood to the fetoplacental unit are abnormally underdeveloped and become high resistance, low perfusion vessels. This decrease in perfusion leads to chronic placental ischemia, which triggers increased release of antiangiogenic factors throughout the maternal circulation. These antiangiogenic factors bind and decrease proangiogenic factors such as vascular endothelial growth factor (VEGF) and placental growth factor. - The overall effect is inhibited angiogenesis and widespread maternal endothelial cell dysfunction, resulting in dysregulated vascular tone --> vasospasm ( hypertension, decreased end-organ perfusion [eg, renal insufficiency]), and abnormally increased vascular permeability (eg, proteinuria). - Decreased human chorionic gonadotropin and prolactin levels are associated with first-trimester pregnancy loss (ie, spontaneous abortion); however, activity levels of *neither hormone are related to preeclampsia*.
How are Prolactin levels related to GnRH?
Prolactin decreases GnRH secretion (which will cause a decrease in LH and FSH)
______ develop from lactotroph cells in the *anterior pituitary (adenohypophysis)*
Prolactinomas
What drugs block TPO and are used to treat Hyperthyroidism?
Propylthiouracil and Methimazole - Beta-blockers are used for fast symptom relief of Hyperthyroidism
What keeps the ductus arteriosus open?
Prostaglandin E2 (indomethicin inhibits this)
BRCA mutations are seen in what cancers?
Prostate and Breast
Tumor Marker: Prostate specific antigen Associations: ???
Prostate cancer
What kind of drug ends in "-navir"?
Protease inhibitors Common side effects include: - metabolic abnormalities (hyperglycemia), - gastrointestinal symptoms, - lipodystrophy.
Which HIV drugs cause Cushing like syndrome?
Protease inhibitors ("-navir")
S aureus uses ________ to bind to the Fc region of Immunoglobulins and to inhibit opsonization and phagocytic engulfment.
Protein A
______ is a natural anticoagulant protein, and deficiency results in a procoagulant state that most commonly manifests with recurrent deep venous thromboses.
Protein C
- Accumulation of calcium pyrophosphate crystals in the synovial fluid - knee joint - Pain, joint swelling, erythema, warmth - Synovial fluid has elevated WBC with neutrophil predominance - Rhomboid-shaped calcium pyrophosphate crystals --> positively befringent under polarized light
Pseudogout, or calcium pyrophosphate deposition disease (CPPD) - normal gout = negative befringent; first metatarsophalangeal joint is more frequently involved
Patients with cystic fibrosis have thick, viscous mucus that accumulates in the airways and promotes colonization of bacteria, particularly _______
Pseudomonas - This gram-negative rod can produce biofilms, which act as a protective matrix that allows bacterial macrocolonies to develop, causing persistent infection. - The abnormal airway secretions in patients with CF impair mucociliary clearance and allow colonization of bacteria such as Haemophilus influenzae, Staph aureus, and, over time, gram-negative rods such as Pseudomonas aeruginosa and Burkholderia cepacia complex. - Bacterial colonization in the lungs of patients with CF induces a massive infiltration of neutrophils, which results in the release of elastase, a protease that promotes *bronchiectasis*
_______ is a rare condition characterized by progressive respiratory dysfunction due to the accumulation of surfactant (periodic acid-Schiff positive material forming lamellar bodies) within the alveolar spaces. The condition occurs most often due to ...
Pulmonary alveolar proteinosis Impaired clearance of surfactant by alveolar macrophages (eg, decreased granulocyte-monocyte colony-stimulating factor signaling). - Surfactant is a lipoproteinaceous material that appears pink with periodic acid-Schiff staining; it forms concentrically laminated structures (ie, lamellar bodies) that can be seen on electron microscopy. - PAP is caused by an imbalance between surfactant production and clearance. In healthy lungs, surfactant is secreted by type 2 pneumocytes and eventually cleared by alveolar macrophages. - In PAP, surfactant removal is impaired due to compromised alveolar macrophage function (eg, usually because of defects in granulocyte-monocyte colony-stimulating factor [GM-CSF] signaling). - Treatment involves therapeutic whole-lung lavage to wash away surfactant and inhaled GM-CSF replacement therapy.
Uncorrected ASD can lead to irreversible medial hypertrophy of the ______ with _______ and ________ .
Pulmonary arteries Pulmonary hypertension and Reversal to right-to-left shunting (ie, Eisenmenger syndrome) - Atrial septal defects cause wide, fixed splitting of the second heart sound due to right-sided volume overload from left-to-right shunting. - ASD causes right atrial dilation. However, these changes are mostly reversible because, *unlike in the pulmonary arteries and often the right ventricle*, significant muscular hypertrophy of the right atrium does not take place. - The pulmonary vascular remodeling is irreversible. Once Eisenmenger syndrome is present, closure of the ASD is not possible because it can increase right-sided pressures even further and lead to acute right-sided heart failure. Therefore, early closure of a hemodynamically significant ASD is needed to avoid irreversible changes to the pulmonary vessels. - Eisenmenger syndrome allows blood to bypass the pulmonary circulation and can cause adult-onset cyanosis, clubbing, and polycythemia.
_______ should be suspected in young and otherwise healthy patients with fatigue, progressive dyspnea, atypical chest pain, or unexplained syncope.
Pulmonary hypertension - Long-standing pulmonary hypertension leads to hypertrophy and/or dilation of the right ventricle (cor pulmonale).
________ can be recognized on physical examination by a loud pulmonic component of S2 and an accentuated, palpable impulse at the left sternal border (left parasternal lift due to right ventricular heave).
Pulmonary hypertension - The disease most commonly presents with progressive dyspnea, and patients may also experience exertional angina or syncope. - In addition, the right ventricle becomes enlarged due to increased pressure load (ie, *concentric right ventricular hypertrophy*), which can create an accentuated impulse palpated at the left sternal border (left parasternal lift due to right ventricular heave). - Right-sided heart failure eventually develops, but because left ventricular function remains intact, there is an *absence of pulmonary edema* in pulmonary arterial hypertension. - Pulmonary arterial hypertension describes pulmonary hypertension directly caused by vascular remodeling of the small pulmonary arteries/arterioles; relatively young women are most commonly affected
What is the MCC of finger clubbing in adults?
Pulmonary malignancy (esp. lung adenocarcinoma) Other causes: Cardiopulmonary disease with hypoxemia - Cyanotic congenital heart disease (R -> L shunting) - Pulmonary arteriovenous malformations - Interstitial lung disease Other causes: Chronic cardiopulmonary infections - Chronic lung abscess - Chronic empyema - Subacute/chronic bacterial endocarditis - Bronchiectasis (CF) - Cavitary infections (fungal, mycobacterial) - for it to be something like bronchitis, etc., there needs to be hypoxemia. No hypoxemia needed for pulmonary malignancy tho
_______ leads to a softer intensity of P2
Pulmonic valve stenosis
What clinical syndrome is expected based on this location of lacunar infarct: Posterior limb of Internal capsule and/or Basilar Pons
Pure motor hemiparesis or Ataxia hemiplagia syndrome (ie, ipsilateral limb ataxia out of proportion to motor deficit)
What clinical syndrome is expected based on this location of lacunar infarct: Ventroposterolateral or Ventroposteromedial stroke
Pure sensory stroke
- Fever, chills, fatigue, chest pain - Examination: pericardial friction rub - Echocardiogram: pericardial effusion - Pericardiocentesis: high number of *leukocytes*/*frank pus*
Purulent pericarditis Pathogenesis - Hematologic spread from a distant source - Direct extension from a heart or lung infection - Complication of penetrating injury or chest wall trauma Common pathogens: - Staphylococcus aureus (portal from skin) - Streptococcus pneumoniae (adjacent pneumonia) - Candida albicans (TPN, severe immunosuppression) [TPN = total parenteral nutrition] - *contrast*: Although single-stranded RNA viruses such as Coxsackievirus can cause pericarditis, the pericardial fluid is usually lymphocyte (not neutrophil) predominant.
Where is insulin cleaved from preproinsulin to proinsulin?
RER
What has a negative RBC agglutination test?
RSV
A massive PE can cause obstructive shock. What changes may be seen in the heart?
RV cavity dilation
Cellular Receptor: Nicotinic Acetylcholine receptor Virus: ????
Rabies Virus - The virus contains a bullet-shaped envelope with knob-like glycoproteins that allow it to attach to the nicotinic acetylcholine receptor at the neuromuscular junction. - The virus replicates locally within the muscle tissue of the bite wound for several days or weeks and then travels in a retrograde fashion through peripheral nerve axons to the dorsal root ganglia. - From there, it rapidly ascends the spinal cord and infects the diencephalon, hippocampus, and brain stem. - Patients initially develop a nonspecific flu-like prodrome (fever, malaise, myalgias); paresthesias radiating proximally from a known wound site can be an important clue. - When the virus enters the CNS, the infection typically evolves into rabies encephalitis, which is characterized by painful pharyngeal spasms leading to avoidance of water (hydrophobia), mental status changes, muscular rigidity, and autonomic dysfunction (pupil dilation, hypersalivation).
The anterior pituitary is formed from an out-pouching of the pharyngeal roof and is called _____ . The posterior pituitary gland arises from an extension of the ______ .
Rathke's pouch hypothalamic neurons - Together, the anterior and posterior pituitary glands lie in the *sella tursica* at the skull base
_______ disorder occurs in children exposed to neglect and abuse and is characterized by decreased emotional responsiveness and lack of response to adult comfort
Reactive attachment disorder
_______ may be defined as the exchange of genes between 2 chromosomes (*double-stranded DNA molecules*) by crossing over within homologous regions.
Recombination - contrast: reassortment requires 2 segmented genomes
Behcet syndrome
Recurrent aphthous ulcers, genital ulcerations, uveitis, erythema nodosum. [Immune complex vasculitis] - High incidence in people of Turkish and eastern Mediterranean descent. - Can be precipitated by HSV or parvovirus. Flares last 1-4 weeks. - Associated with HLA-B51
Risk factors for magnesium ammonium phosphate (struvite) stone formation
Recurrent upper urinary infection (eg, Klebsiella, Proteus)
_________ , often caused by excessive chronic analgesic use, demonstrates cortical atrophy with necrotic, sloughing papillae
Renal Papillary necrosis
______ is a benign tumor composed of blood vessels, smooth muscle, and fat. If bilateral, it is associated with_____ , an autosomal dominant condition.
Renal angiomyolipoma tuberous sclerosis (TSC) - Angiomyolipomas are associated with tuberous sclerosis. In patients with bilateral renal angiomyolipomas, the incidence of tuberous sclerosis is 80%-90%. Tuberous sclerosis is an autosomal dominant condition characterized by cortical tubers and subependymal hamartomas in the brain, with consequent seizures and cognitive disability. Cardiac rhabdomyomas, facial angiofibromas, and leaf-shaped patches of skin lacking pigment (ash-leaf patches) can also occur. - These brain hamartomas are composed of atypical glial and neuronal elements and often calcify. The first dermatologic manifestation of TSC is usually ash-leaf spots (ie, hypopigmented macules). Other classic cutaneous findings usually develop later and can include facial angiofibromas (ie, adenoma sebaceum), periungual fibromas, and hamartomatous plaques of connective tissue (ie, shagreen patches).
_________ classically causes hematuria, flank pain, polycythemia, and a palpable mass
Renal cell carcinoma - Polycythemia due to EPO release
Rotavirus genome
Reoviridae - dsRNA, non-enveloped, segmented
_______ causes *arrested brain development* around 6-18 months of age
Rett syndrome
Symptoms of ________ usually appear between ages 1-4 and are characterized by regression in motor, verbal, and cognitive abilities; ataxia; seizures; growth failure; and stereotyped hand- wringing.
Rett syndrome - It affects mainly girls and is associated with mutations in the MECP2 gene.
- immune-mediated complication of streptococcal infections - migratory arthritis - carditis - subcutaneous nodules - rash (erythema marginatum) - chorea. - age 5-15
Rheumatic fever -age 5-15 and presents acutely 2-4 weeks after an episode of untreated pharyngitis. J♥NES (major criteria): - Joint (migratory polyarthritis) - ♥ (carditis) - Nodules in skin (subcutaneous) - Erythema marginatum (evanescent rash with ring margin) - Sydenham chorea mitral > aortic >> tricuspid (high-pressure valves affected most). - Early lesion is mitral valve regurgitation; late lesion is mitral stenosis. Associated with: - Aschoff bodies (granuloma with giant cells [blue arrows in A ]), - Anitschkow cells (enlarged macrophages with ovoid,wavy, rod-like nucleus [red arrow in A ]) - Increased anti-streptolysin O (ASO) and increased anti-DNase B titers. - Immune mediated (type II hypersensitivity) - not a direct effect of bacteria. Antibodies to M protein cross-react with self antigens, often myosin (molecular mimicry). - Treatment/prophylaxis: penicillin.
_______ can cause a variety of pulmonary manifestations; the most common is a form of interstitial lung disease similar to idiopathic interstitial pneumonia. In addition, multiple agents used to treat this condition (eg, ________ ) can cause fibrotic lung disease.
Rheumatoid arthritis (RA) methotrexate, cyclophosphamide, sulfasalazine - Auscultation may have *end-inspiratory crackles*
Cellular Receptor: ICAM1 (CD54) Virus: ????
Rhinovirus
____ , _____ , and _____ are the saprophytic fungi that cause mucormycosis in immunosuppressed patients. Mold forms of _____ and _____ are found with nonseptate hyphae and wide angle branching (90º). *The typical presentation is a paranasal infection in diabetic ketoacidosis patients.*
Rhizopus, Mucor, and Absidia Rhizopus and Mucor - Broad non-septate hyphae are seen in tissue specimens.
Mucormycosis is an opportunistic infection caused by_________ . The classic clinical picture is paranasal sinus involvement in a diabetic or immunosuppressed patient. The fungi form broad non-septate hyphae that branch at right angles.
Rhizopus, Mucor, and Absidia species - Mostly in ketoacidotic diabetic and/or neutropenic patients (eg, leukemia). Inhalation of spores --> fungi proliferate in blood vessel walls, penetrate cribriform plate, and enter brain. - Rhinocerebral, frontal lobe abscess; cavernous sinus thrombosis. Headache, facial pain, black necrotic eschar on face; may have cranial nerve involvement. - Treatment: surgical debridement, amphotericin B or isavuconazole. - Invasive aspergillosis involving the paranasal sinuses can show close clinical resemblance to mucormycosis. However, light microscopy of the affected tissue will differentiate these two diagnoses: unlike Mucor and Rhizopus, Aspergillus has septate hyphae that branch at 45° angles (V-shaped branching).
______ is characterized by extensive fibrosis of the thyroid extending into the surrounding structures. The fibrotic gland is typically hard and fixed, often resembling a malignancy.
Riedel thyroiditis
Resistance to ________ in M tuberculosis is primarily due to a mutation in the gene that codes for a DNA-dependent RNA polymerase necessary for transcription and RNA prolongation.
Rifampin
Colon cancers located where usually grow as exophytic masses and present with occult bleeding and symptoms of iron deficiency anemia (weight loss, progressive fatigue, etc.)?
Right-sided - liver and lung are common sites of metastasis
_________ is due to Rickettsia rickettsii, which is transmitted by ticks
Rocky Mountain spotted fever
________ infects villous enterocytes in the duodenum and proximal jejunum and results in villous blunting, proliferation of secretory crypt cells, and a loss of brush border enzymes; this results in watery diarrhea without fecal leukocytes.
Rotavirus
________ is a surgical emergency that usually presents with the acute onset of severe abdominal and back pain in patients with appropriate risk factors (eg, advanced age, smoking, atherosclerosis).
Ruptured abdominal aortic aneurysm - Accompanying syncope, hypotension, and shock may occur quickly (intraperitoneal rupture) or may be delayed (retroperitoneal rupture). - *contrast*: Colonic perforation can be due to diverticulitis, malignancy, or complications from colonoscopy. Patients can develop hypotension due to sepsis, but signs of infection (eg, fever) and peritonitis (eg, rebound, guarding) are also expected. - *contrast*: Acute mesenteric ischemia has similar risk factors to AAA. Patients typically describe severe abdominal pain but have few findings on physical examination (eg, minimal tenderness) and hypotension and syncope are not usually seen.
_____- is the most common cause of meningitis in neonates.
S agalactiae (group B Streptococcus)
Cause of otitis media
S pneumoniae H influenza (non-typeable) Moraxella cataralis Pathophysiology: - Viral URI → obstructs eustachian tube - Middle ear secretions → bacterial overgrowth of respiratory colonizers - Immune response with suppurative fluid accumulation
When is S3 heard?
S3 is often heard in pathologic settings causing high ventricular filling pressures and/or volume overload, particularly aortic or mitral regurgitation and dilated cardiomyopathy. [systolic HF; may see accompanied R sided HF with distended neck veins, etc.] [normal if age < 40 or in pregnancy]
Anal wink reflex
S3-S4 "winks galore"
Alpha 1 anti-trypsin deficiency gene/chromosome defect
SERPINA1 gene on chromosome 14 and PiMM gene on chromosome 14
Is an osteoblastic lesion described as lucent or sclerotic?
Sclerotic - Osteolytic (lucent): Due to osteoclast stimulation, tend to represent aggressive cancer - Osteoblastic (sclerotic): Due to osteoblasts, indicates a more indolent course
Bacterial invasion of the intestinal mucosa by _______ causes inflammatory/bloody diarrhea
Salmonella, Enteroinvasive E coli (EIEC) Campylobacter jejuni
_________ , which can present acutely as swimmer's itch (organism penetration into skin) or Katayama fever (fever, urticaria, angioedema, eosinophilia), can affect the bladder (causing terminal hematuria, fibrosis); chronic infection is a risk factor for bladder cancer.
Schistosomia haematobium
- adults - biphasic pattern of cellularity (Antoni A and B areas) - S-100 positivity (indicating neural crest origin)
Schwannoma
- Dyspnea, - uneven chest expansion. - Chest pain, - decreased tactile fremitus - hyperresonance, - diminished breath sounds - ALL ON THE EFFECTED SIDE Due to diseased lung (eg, bullae in emphysema, infections), mechanical ventilation with use of high pressures --> barotrauma.
Secondary spontaneous pneumothorax
_______ is produced by S cells of the small intestine. It increases bicarbonate production by the pancreas and leads to the secretion of watery, alkaline pancreatic juice.
Secretin - This substance also inhibits gastric acid secretion and stimulates pyloric sphincter contraction.
______ is produced by S cells in duodenal mucosa
Secretin - in response to stimulation by intraluminal acidity. - Secretin stimulates the release of bicarbonate-rich secretions from the exocrine pancreas, which is the major source of acid-neutralizing bicarbonate entering the duodenum. - The chloride content of pancreatic secretions *decreases* in proportion to bicarbonate concentration increases (inversely proportional)
A high synovial fluid leukocyte count (>100,000/mm3) and absent crystals on microscopic examination strongly suggest _______ , which requires _______ treatment
Septic arthritis [bacterial joint infection; often due to gonococcus if patient is young] Antibiotic [to prevent joint destruction, osteomyelitis, and sepsis.]
- Most common malignant ovarian neoplasm - Psammoma bodies.
Serous cystadenocarcinoma
- Small, grey to yellow-brown mass - Resembles testicular histology with tubules/ cords lined by pink Sertoli cells. - May produce androgens --> virilization (eg, hirsutism, male pattern baldness, clitoral enlargement).
Sertoli-Leydig cell tumor (benign) - sex cord stromal tumor
________ are reflective of liver function and are of greatest prognostic significance in patients with cirrhosis.
Serum albumin levels, bilirubin levels, and prothrombin time - contrast: Fibrinogen is a coagulation factor and an acute phase protein. Liver fibrinogen synthesis is increased in response to infection or acute inflammation and diminished in liver failure. Therefore, low fibrinogen levels would be expected in liver failure.
______ is an immune complex-mediated type III hypersensitivity reaction that typically forms 5-14 days after exposure to foreign proteins in an antitoxin, antivenom, monoclonal antibody, or vaccine. Patients typically develop fever, urticarial rash, and arthralgia that resolve spontaneously over days as the immune complexes are cleared by the _______ .
Serum sickness mononuclear phagocyte system - in serum sickness, most of the inflammatory response is due to C3a and C5a (anaphylatoxins) --> C3a and C5a are potent chemoattractants that dramatically increase phagocyte recruitment (eg, neutrophils, macrophages) to areas of IC deposition due to effects on the vasculature (eg, vasodilation, increased permeability) and immune cells (eg, increased adhesion molecule expression). This leads to development of local (eg, skin rash, joint pain/effusion, neutrophilic joint effusion) and systemic (eg, high fever, elevated erythrocyte sedimentation rate) inflammatory manifestations that resolve spontaneously over a few days as the ICs are processed/removed by phagocytes. [increase synovial membrane permeability, etc.]
_________ is an immune complex-mediated ________ hypersensitivity reaction that occurs 1-2 weeks after exposure to nonhuman protein in antitoxins (eg, antivenom), monoclonal antibodies (eg, rituximab), or vaccines (eg, rabies antigens). Deposition of immune complexes in tissue leads to complement activation and subsequent self-limited fever, arthralgia, and urticarial rash.
Serum sickness type III
The zona reticularis secretes what hormone(s)?
Sex steroids (androgens and estrogens)
The ________ cause inactivation of the 60S ribosomal subunit
Shiga toxin of Shigella and the shiga-like toxin of Enterohemorrhagic Escherichia coli (EHEC)
Mucosal invasion of the M cells that overlie Peyer's patches is an essential pathogenic mechanism for ______ infection.
Shigella - Shigella then escapes the phagosome and spreads laterally to other epithelial cells via actin polymerization.
HER-2 is normally involved in
Signal transduction (tyrosine kinase specifically) - therefore, mutation causes aberrant signal transduction --> accelerated cell proliferation --> cancer
Histology for __________ demonstrates nodules composed of whorled collagen fibers and dust-laden macrophages. Imaging demonstrates innumerable upper lobe-predominant nodes within the pulmonary parenchyma.
Silicosis
Lambert-Eaton Syndrome is associated with which cancer?
Small cell carcinoma of the lung
What does a tumor of somatotrophs cause?
Somatotroph (cell type) secretes GH --> gigantism or acromegaly - Acromegaly can affect the joints in both the axial and the appendicular skeleton. Excessive growth hormone and insulin-like growth factor-1 cause *hyperplasia of articular chondrocytes and synovial hypertrophy*, leading to later *degeneration of articular cartilage and periarticular bone*.
Antibodies for Dermatomyositis and Polymyositis
Specific: - ⊕ anti-Jo-1 (histidyl-tRNA synthetase), - ⊕ anti-SRP (signal recognition particle), - ⊕ anti-Mi-2 (helicase).
Failure of caudal neuropore to close, but no herniation. Usually seen at lower vertebral levels. Dura is intact. Associated with tuft of hair or skin dimple at level of bony defect.
Spina bifida oculta - Neural Tube defects: Neuropores fail to fuse (4th week) --> persistent connection between amniotic cavity and spinal canal. Associated with maternal diabetes and folate deficiency. Increased α-fetoprotein (AFP) in amniotic fluid and maternal serum (except spina bifida occulta = normal AFP). Increased acetylcholinesterase (AChE) in amniotic fluid is a helpful confirmatory test.
Weakness raising arm over 100° + shoulder droop = injury to what nerve/muscle?
Spinal accessory nerve (CN11) + Trapezius muscle - no shoulder droop = long thoracic nerve + Serratus anterior (winged scapula may be seen)
Hemodynamic changes in portal HTN (ex alcoholic liver cirrhosis)
Splanchnic vasodilation --> decreased splanchnic vascular resistance and lowers effective arterial blood volume --> causes activation of RAAS --> Na and H2O retention - Additionally, low oncotic pressure (ie, hypoalbuminemia due to impaired hepatic function) reduces fluid resorption from the interstitium - Ascites develops
_______ is intercellular epidermal edema that histologically appears as an increase in the width of spaces between cells
Spongiosis
_________ is common in cystic fibrosis and involves alveolar rupture, leading to loss of intrapleural negative pressure. Patients have sudden-onset shortness of breath, unilaterally decreased breath sounds, and, sometimes, subcutaneous crepitus.
Spontaneous pneumothorax - Hypotension and tachycardia suggest the development of tension pathophysiology. - In cystic fibrosis, chronic lung damage, combined with mucus plugging and large alveolar pressure surges (eg, coughing), predisposes to spontaneous alveolar rupture.
What allows Clostridium botulinum to survive adverse conditions?
Spore formation - Clostridium botulinum is a spore-forming, gram-positive, anaerobic bacillus that synthesizes botulinum toxin, which prevents the presynaptic release of acetylcholine from the nerve terminal at the neuromuscular junction. Botulinum toxin can be used to treat focal dystonia and other disorders of abnormal muscle contraction. - Spore formation, which occurs in the subterminal location (between the terminal end and center of the bacteria), allows the bacteria to survive adverse conditions (eg, heat, high-oxygen environment). - Torticollis is a common manifestation of dystonia and is due to involvement of the sternocleidomastoid muscle. Injection of botulinum toxin type B into the dystonic muscle results in muscular relaxation and relief of symptoms. Botulinum toxin can also be used to treat the muscle spasms of multiple sclerosis and Parkinson disease, to relax the lower esophageal sphincter in achalasia, and to reduce the appearance of facial wrinkles. The localized anticholinergic effect also makes it useful in the treatment of hyperhydrosis. The effects are temporary (approximately 3 months), due to the regeneration of the nerve terminal with time.
Achalasia increases the risk of which carcinoma?
Squamous cell carcinoma
Patients with chronic granulomatous disease (CGD), a condition that results in recurrent bacterial and fungal infections due to impaired intracellular killing by phagocytes becacuse of a genetic defect in the *NADPH oxidase* complex, are susceptible to catalase-positive organisms, particularly:
Staphylococcus aureus Burkholderia cepacia Aspergillus Nocardia Serratia marcescens [SBANS]
Haemophilus influenzae is a "blood-loving" organism that requires X (hematin) and V (NAD+) factors for growth. This can be accomplished by growing H influenzae in the presence of ____________
Staphylococcus aureus (can provide NAD+ to H influenza)
Which bacteria produces golden yellow pigments?
Staphylococcus aureus produces golden yellow pigments. - Other bacteria producing pigments include Pseudomonas aeruginosa (blue-green) and Serratia marcescens (red).
__________ , a coagulase-negative Staphylococcus species, causes virulence via synthesis of extracellular polysaccharide matrix (biofilm)
Staphylococcus epidermidis - biofilm functions as a barrier to antibiotic penetration and interferes with host defenses, including opsonization, neutrophil migration, and even T lymphocyte activation
When does stranger anxiety develop and resolve?
Starts around 6 months Resolves on its own by 2 years old
The non-NRTIs efavirenz and nevirapine may cause what as AE?
Stevens-Johnson syndrome and toxic epidermal necrolysis
_________ is a benign capillary hemangioma of infancy. Appears in first few weeks of life (1/200 births); grows rapidly and regresses spontaneously by 5-8 years old.
Strawberry hemangioma
What is the number 1 cause of meningitis in adults? What is its shape/genome?
Strep pneumoniae Lancet shaped, Gram positive cocci in pairs - Streptococcus pneumoniae is a leading cause of community-acquired pneumonia, otitis media, and meningitis in adults
__________ , one of the most common causes of early neonatal sepsis, is typically identified by the presence of a narrow zone of beta-hemolysis when plated on blood agar
Streptococcus agalactiae (group B Streptococcus) - It is also identified by the production of CAMP factor, which enhances beta-hemolysis by particular strains of Staphylococcus aureus.
The most common cause of both otitis media and community-acquired pneumonia in adults is ____________
Streptococcus pneumoniae
Asplenic patients (ex: patients with Sickle cell) are more susceptible to encapsulated organisms, such as:
Streptococcus pneumoniae (leading pathogen) Neisseria meningitidis Haemophilus influenzae
__________ produce IgA proteases that cause cleavage of IgA antibodies, preventing them from interfering with bacterial adhesion to mucous membranes.
Streptococcus pneumoniae and Neisseria gonorrhoeae
_______ is due to loss of pelvic floor support and *incompetence of the urethral sphincter*. Increased abdominal pressure (eg, coughing, sneezing, or vigorous effort) greater than the urethral sphincter pressure can cause brief involuntary urine loss, which is virtually diagnostic.
Stress incontinence
_______ in the lung trigger cessation of inspiration when the lung is approaching total lung capacity.
Stretch receptors
Nematode route of infection: cutaneous
Strongyloides Ancylostoma Necator
Rhabditiform larvae are seen in feces under microscope for
Strongyloides stercoralis (threadworm) [larvae in soil penetrate skin] *Sxs*: GI (eg, duodenitis), pulmonary (eg, dry cough, hemoptysis), and cutaneous (eg, pruritus) symptoms. Hyperinfection syndrome caused by autoinfection (larvae enter bloodstream).
- congenital neurocutaneous disorder - cutaneous facial angiomas + leptomeningeal angiomas. - mental retardation, - seizures, hemiplegia, and skull radiopacities. - Skull radiographs may show characteristic "tram-track" calcifications.
Sturge-Weber syndrome (encephalotrigeminal angiomatosis)
_____ thyroiditis is characterized by the disruption of follicles and a mixed cellular infiltrate with occasional multinucleated giant cells.
Subacute granulomatous (de Quervain/postviral) thyroiditis - It typically presents after a viral upper respiratory infection with fever and a painful, tender thyroid.
______ herniation occurs when the cingulate gyrus is displaced under the falx cerebri. This herniation may compress the ipsilateral anterior cerebral artery, resulting in ischemia and _______ .
Subfalcine contralateral leg weakness - No pupillary involvement, consciousness often preserved
______ occurs when a surrogate decision-maker makes a health care decision for an incapacitated patient based on the surrogate's knowledge of the patient's wishes and values.
Substituted judgment
What drugs have the following MOA: ↑ Insulin secretion by inhibiting β-cell K-ATP channels (membrane ion channels)?
Sulfonylureas 1st gen: [disulfuram-like rxns] - Chlorpropamide, - tolbutamide Sulfonylureas 2nd gen: - Glipizide, - Glyburide - Glimepiride Meglitinides ("-glin") [less potent; faster onset, shorter duration] - Nateglinide, - Repaglinide
Which diabetes drugs can cause weight gain?
Sulfonylureas and Meglitinides ("-glins")
Hemorrhoids (piles) involves which blood supply?
Superior rectal vein (portal) + inferior and middle rectal vein -> internal illiac vein
ADH is secreted by what part of the hypothalamus
Supraoptic nucleus (later stored in posterior pituitary)
An increase in what causes "Target cells" to form?
Surface area-to-volume ratio
Ectopic pregnancy symptoms + Treatment
Symptoms: - 1st trimester symtpoms - Vaginal bleeding - Abdominal pain (may mimic appendicitis) - Abnormal increase in hcg based on date - May see adnexal mass Diagnosis: ultrasound Treatment: *Methotrexate* or Surgery *Risk factors*: - Damage to fallopian tube - Prior ectopic pregnancy - *Tubal disorders* -- Tubal ligation (rarely pregnancy occurs) -- Tubal surgery (tumor) -- *Pelvic inflammatory disease (chlamydia, neisseria)* -- infertile women -- Kartagener syndrome (1° ciliary diskinesia; fallopian tubes have ciliated epithelium)
Anti-dsDNA antibodies are specific for _____
Systemic lupus erythematosus (SLE) (also maybe Anti-Sm antibodies) - Anti-phospholipid antibodies are found in patients with SLE and in antiphospholipid antibody syndrome. - Antiphospholipid antibody syndrome causes a hypercoagulable state and patients may suffer recurrent miscarriages. Partial thromboplastin time (PTT) is paradoxically increased in these patients despite the propensity toward thrombosis.
In Wiskott-Aldrich syndrome, there is defective WAS gene/protein. What is it necessary for normally?
T cell *cytoskeleton* maintenance - forms "immunologic synapse" --> T cells cannot properly react to APCs
Local defense against Candida is performed by _____ , whereas systemic infection is prevented by ______ .
T cells Neutrophils - For this reason, localized candidiasis is common in patients who have HIV, but neutropenic individuals are more likely to have the systemic form of the disease.
Interferon-gamma (IFN-γ) release assays test for latent tuberculosis infection by measuring the amount of IFN-γ released by _______ when exposed to antigens unique to Mycobacterium tuberculosis.
T lymphocytes
Sensitization to aeroallergens occurs when inhaled antigens induce ...
T-helper (Th) cells to differentiate into Th2 cells. Th2 cells then promote B-cell maturation and isotype class switching to IgE.
- thick, gelatinous exudate in the base of the brain - cerebral vasculitis - hydrocephalus
TB meningitis - Frequently presents with subacute, slowly progressive nausea, vomiting, fever, cranial nerve deficits, and strokes.
Which thyroid hormone can stimulate lactotrophs (which secretes prolactin)?
TRH - In patients with primary hypothyroidism (ex: Hashimotos), the increased production of TRH by the hypothalamus can lead to hyperprolactinemia.
In Hashimotos (hypothyroidism) or even Post-Partum thyroiditis, are the TSH levels elevated, normal, or decreased?
TSH is elevated, and T4 is decreased - decreased TSH = secondary hypothyroidism (like Sheehan syndrome, etc.)
Besides finasteride and TURP, what can be used to treat BPH?
Tadalafil - PDE-5 inhibitor - Causes smooth muscle relaxation - Can cause visual reflects Tamsulosin - causes *smooth muscle* relaxation - Uroselective *Alpha-1a blocker* --> no hypotension (b/c doesn't block alpha-1b)
_________ has an estrogenic effect on the uterus and can cause endometrial hyperplasia and cancer.
Tamoxifen - Tamoxifen and Raloxifine [SERMs] can increase bone density - Tamoxifen has a favorable effect on serum lipids, with a decrease in total and LDL cholesterol and no significant change in HDL. Serum triglycerides may increase in some patients.
______ cortex injury can cause disturbances in language, sensory interpretation, and impaired memory. These patients can also exhibit behavioral changes, such as apathy, hyperorality, hypersexuality, and visual agnosia as seen in Klüver-Bucy syndrome. Nondominant (usually right-sided) lesions can affect nonverbal memory, including musical ability; dominant left-sided lesions can affect verbal memory, such as word recognition
Temporal
- Dyspnea, - uneven chest expansion. - Chest pain, - decreased tactile fremitus - hyperresonance, - diminished breath sounds - ALL ON THE EFFECTED SIDE Air enters pleural space but cannot exit. Increasing trapped air *Trachea deviates away from affected lung* - - *unilateral* breath sounds are present
Tension pneumothorax - can be from anytime of pneumothorax May lead to increased intrathoracic pressure --> mediastinal displacement --> kinking of IVC --> decreased venous return --> decreased cardiac output. Needs immediate needle decompression and chest tube placement. - Hypotension, tachycardia, and obstructive shock develop due to *decreased venous return to the heart*.
_________ is an alpha-1 adrenergic antagonist used in the treatment of benign prostatic hyperplasia and hypertension.
Terazosin - Major adverse effects include lightheadedness and orthostatic hypotension.
__________- inhibits the fungal enzyme squalene epoxidase, which ultimately results in decreased ergosterol synthesis.
Terbinafine - accumulates in skin and nails and is used to treat dermatophytosis.
Bile salt malabsorption typically occurs with conditions affecting what area?
Terminal ileum (eg, ileal resection, Crohn ileitis). - Patients may have diarrhea as a result of excessive bile salt accumulation in the colon (cholerheic enteropathy).
_________ (due to contaminated ________ ingestion) leads to inhibition of sodium influx into nerve cells. Manifestations include weakness, paresthesias (face, extremities), loss of reflexes, and sometimes severe hypotension. Patients commonly remain conscious, although paralyzed.
Tetrodotoxin poisoning puffer fish
Granuloma formation involves what cells?
Th1 [produce IFN-gamma* and IL2] and Macrophages - Activated antigen-presenting cells produce *IL-12*, which stimulates the differentiation of Th1-type CD4+ cells. - Th1 cells produce IL-2 and interferon-γ, which stimulate Th1 cell proliferation and macrophage activation, respectively.
Which T cells are involved in the pathogenesis of UC?
Th2 cells (produce IL5 and 13) [Th1 = Crohns disease (think granuloma)]
What secreted Brain Natriuretic peptide and under what circumstances?
The *ventricular myocardium* does in response to stretch/strain that comes from *volume overload* [Atrial myocardium releases Atrial Natriuretic Peptide in response to atrial stretching] - BNP and ANP stimulate both venous and arterial vasodilation to decrease cardiac preload and afterload and reduce strain on the myocardium. In addition, ANP and BNP stimulate salt and water excretion by the kidneys to facilitate diuresis.
______ is secreted by inflammatory cells (ex: *Macrophages*) and results in the recruitment of fibroblasts and the deposition of connective tissue.
Transforming growth factor-beta (TGF-beta) - This cytokine contributes to scar formation after injury and plays a role in the fibrosis seen with chronic inflammation.
How does the Hep B vaccine give the patient immunity?
The the HBV vaccine helps generate anti-HBs antibodies, which bind to circulating viral particles and *prevent attachment to and penetration of hepatocytes*. - The immunity conferred by the hepatitis B vaccination is mediated by protective antibodies against HBsAg; the protective effects are not due to activation of cytotoxic T cells. However, in patients exposed to HBV, the resolution of acute infection is mediated primarily by a vigorous, polyclonal cytotoxic T-cell response that destroys infected hepatocytes.
___________ run in close proximity to the pelvic lymph nodes and the uterine artery in the female pelvis, which predisposes them to injury during pelvic surgery.
The ureters
- Often bilateral/multiple - Due to gonadotropin stimulation - Associated with choriocarcinoma and hydatidiform moles.
Theca-lutein cyst
- May produce estrogen - Usually presents as abnormal uterine bleeding in a postmenopausal woman.
Thecoma (benign) - sex cord stromal tumor
_______ is generally defined as naked DNA uptake by a prokaryotic or eukaryotic cell. In virology, this term may also describe incorporation of viral DNA into a host cell chromosome.
Transformation - Transformation alters the genetic composition of the host cell but typically causes no genomic change in progeny virions.
Patients with chronic gastritis have a high association with developing:
They are at increased risk for, due to chronic inflammation, gastric ulcers and malignancy, particularly: - gastric lymphoma (ie, mucosa-associated lymphoid tissue [MALT] lymphoma) - gastric adenocarcinoma. - Patients with chronic gastritis are less likely to develop duodenal ulcers
Where are the renal juxtaglomerular cells that release renin?
They are modified smooth muscle cells in the walls of afferent glomerular arterioles - A markedly narrowed renal artery (eg, due to an atherosclerotic plaque or external clip) cannot supply the kidney with enough blood to maintain a normal glomerular filtration rate. The reduced blood flow is sensed by the juxtaglomerular (JG) apparatus, which consists of the macula densa, extraglomerular mesangial cells (ie, Lacis cells), and JG cells. Macula densa cells are tall, narrow cells located in the distal tubule that monitor salt content and tubular flow rate. This information is transmitted to nearby JG cells that are located mainly in the wall of the afferent arteriole. JG cells are modified smooth muscle cells with renin-containing zymogen granules. - Significant renal hypoperfusion leads to a compensatory increase in renin secretion by JG cells. This activates the renin-angiotensin-aldosterone system, leading to increased levels of angiotensin II and aldosterone. Long-term renal hypoperfusion, such as caused by renal artery stenosis, leads the JG cells of the affected kidney(s) to undergo hyperplasia as a result of chronic stimulation. - If the renal artery stenosis is unilateral, then chronic kidney disease does NOT occur
_______ deficiency is a benign disorder characterized by low total thyroxine (T4) and normal free T4 and TSH levels. Patients are euthyroid and do not require treatment.
Thyroxine-binding globulin - In general, the majority of circulating T4 is bound to TBG, which then serves as a storage pool to replenish the biologically active free T4 that is continuously cleared by the kidneys. Therefore, TBG helps maintain a constant free T4 level. - When TBG is deficient, less T4 is bound and a greater proportion is allowed to freely circulate. Total T4 is low due to the decrease in bound T4 fraction. However, since physiologic feedback is intact, TSH and free T4 levels remain normal. Because the levels of active (free) thyroid hormone are normal, patients are clinically euthyroid and asymptomatic, so no treatment is required.
Pancreatic cancer risk factors
Tobacco smoking Obesity
_________ is used for the treatment of impetigo, a superficial bacterial infection caused by Staphylococcus aureus and Streptococcus pyogenes. The condition typically presents as a localized papulovesicular rash with surrounding erythema and adherent golden crusts involving the face or extremities.
Topical mupirocin
________ is caused by infection with dog or cat roundworms. Migrating larva cause a significant eosinophilic granulomatous response that can result in ocular (endophthalmitis) and organ damage. Diagnosis is made by serology; the organism does not shed eggs in the gastrointestinal tract.
Toxocariasis
___________ is critical for fibroblast migration, proliferation, and connective tissue synthesis. Increased _________ activity is responsible for the hypertrophic/keloid scarring and fibrosis of the lung, liver, and kidney that occur with chronic inflammation.
Transforming growth factor-β (TGF-β)
Carcinogen: Aromatic amines (ex: benzidine, 2-napthylamine) Cancer: ???
Transitional cell carcinoma (bladder) Exposure: textile industry (dyes), cigarette smoke (2-naphthylamine)
BPH is in what zones?
Transitional zone (and central) and Peri-urethral zone - may get hematuria due to friable new blood vessels in prostate - may get overflow incontinence
______ is incompatible with life unless there is another coexisting connection, such as a patent foramen ovale, septal defect, or patent ductus arteriosus (PDA), to allow mixing of oxygenated pulmonary circulation blood with the systemic circulation.
Transposition of Great Arteries - Patients may be normal on initial presentation but will become cyanotic, tachypneic, and tachycardic as the PDA (machine-like murmur) begins to close, which typically occurs at age 1-3 days. Elevated lactate in this patient signifies anaerobic metabolism in the presence of poorly oxygenated blood. - An echocardiogram showing an aorta lying anterior to the pulmonary artery is diagnostic of transposition of the great arteries (TGA). This life-threatening cyanotic condition results from failure of the fetal aorticopulmonary septum to spiral normally during septation of the truncus arteriosus. - The etiology of TGA is due to linear (rather than spiral) development of the aorticopulmonary septum in utero, resulting in an anteriorly positioned aorta connected to the right ventricle and a posteriorly positioned pulmonary artery connected to the left ventricle. Therefore, pulmonary and systemic circulations are abnormally separated and exist as 2 parallel circulations.
Alternate names for Flexor Retinaculum
Transverse carpal ligament Anterior annular ligament
- Dyspnea, - uneven chest expansion. - Chest pain, - decreased tactile fremitus - hyperresonance, - diminished breath sounds - ALL ON THE EFFECTED SIDE Caused by blunt (eg, rib fracture), penetrating (eg, gunshot), or iatrogenic (eg, central line placement, lung biopsy, barotrauma due to mechanical ventilation) trauma.
Traumatic pneumothorax
__________ antifungals inhibit ergosterol synthesis by inhibiting the demethylation of lanosterol into ergosterol
Triazoles (eg, ketoconazole, fluconazole, itraconazole, voriconazole) - monitor liver function tests with azoles --> inhibit liver cytochrome P450 [drug interactions] - For this reason, medications such as warfarin, cyclosporine, tacrolimus, and oral hypoglycemics should be avoided (or have their use carefully monitored) in patients who are receiving azole therapy. - Cytochrome oxidase inducers (eg, rifampin, phenytoin, carbamazepine, phenobarbital) increase azole metabolism, thereby lowering azole concentration in serum.
Patients with ______ classically have a cervix with punctate hemorrhage (ie, strawberry cervix).
Trichomonas cervicitis
_______ is a sexually transmitted infection that often presents with a malodorous, thin, frothy, yellow-green vaginal discharge. The trichomonads infect the squamous epithelium of the vagina, resulting in vulvovaginal inflammation and subsequent vulvar pruritus, dyspareunia, vulvovaginal erythema, and discharge. ______ of trichomoniasis typically shows characteristic motile, flagellated protozoans.
Trichomonas vaginalis Wet mount saline microscopy - Trichomonas vaginalis is a *flagellated protozoan* that causes trichomoniasis - *Nucleic acid amplification testing can also be performed and is the gold standard.* - Treatment of the patient and the patient's sexual partners is with metronidazole.
_______ is a dermatophyte that causes tinea capitis, which presents as a scaly, erythematous patch of hair loss. There are often small, black dots that represent broken hair shafts.
Trichophyton tonsurans
Easy way to differentiate mitral and tricuspid regurg.?
Tricuspid increases with inspiration
T/F: the physician should neither confirm nor deny whether the person of interest is, in fact, a patient.
True
_________ is relatively specific to mast cells and can be used as a marker for mast cell activation.
Tryptase Anaphylaxis is the result of widespread mast cell and basophil degranulation and the release of preformed inflammatory mediators, including histamine and tryptase.
What AA is the precursor for serotonin?
Tryptophan
- Autosomal dominant disorder - Abnormal tuberin and hamartin.
Tuberous sclerosis
Benign tumors in: - the skin (eg, ash-leaf lesions, angiofibromas), - central nervous system (eg, subependymal giant cell astrocytomas [SEGA]) - other tissues. - SEGA commonly presents as an intraventricular mass composed of large cells with abundant eosinophilic cytoplasm; necrosis and microvascular proliferation would be atypical.
Tuberous sclerosis
Mutations in tuberin and harmartin are seen in_______
Tuberous sclerosis - These patients may develop cardiac rhabdomyomas in ventricular walls and AV valves, cutaneous angiofibromas (adenoma sebaceum), central nervous system hamartomas, and renal cysts. However, septal defects are not characteristic. - AD, variable expression. Mutation in tumor suppressor genes TSC1 on chromosome 9 (hamartin), TSC2 on chromosome 16 (tuberin). - increased incidence of Subependymal giant cell astrocytomas and ungual fibromas.
Manifestations of ________ , a gram negative bacterium that frequently infects rabits, typically include flulike symptoms followed by lymphadenopathy and a papulo-ulcerative eschar at the site of inoculation.
Tularemia - Tularemia is caused by the gram-negative bacterium Francisella tularensis, which frequently infects rabbits.
______ is the most important prognostic determinant for colorectal cancer.
Tumor stage (degree of invasion/spread) - Tumors confined to the basement membrane and lamina propria are early stage and have the best prognosis. - Outcomes generally deteriorate as the stage advances: spread of tumor into the muscularis propria → regional lymph nodes → distant sites.
Congenital hypertrophic pyloric stenosis is associated with:
Turner Syndrome Trisomy 18 (Edwards syndrome) - every prenatal marker is decreased in this condition Esophageal atresia
What type of collagen is defective in Osteogenesis imperfecta?
Type 1 (type 2 = cartilage/hyaline/vitreous humor/nucleus pulpus) (Type 3 = Ehler Danlos) (Type 4 = basement membrane) - Mutation in genes encoding α1 and α2 chains of type 1 collagen --> Glycine residue replaced by another amino acid --> Triple helix not formed properly--> Misfolding of collagen polypeptides and defective assembly
___________ presents with escalating fever, followed by abdominal pain, formation of rose spots on the chest/abdomen, and hemorrhagic enteritis with possible bowel perforation
Typhoid fever is caused by Salmonella Typhi or Paratyphi and - Humans are the only reservoir; transmission is fecal-oral and primarily occurs due to ingestion of food or water contaminated with feces.
______ pass through enterocytes and invade macrophages in the intestinal submucosa and Peyer patches. Inflammation and necrosis of Peyer patches can lead to life-threatening gastrointestinal bleeding and perforation.
Typhoid strains of Salmonella
Post-partum depression
Typically within 4-6 weeks (can be up to 1 year)
What is a precursor for dopamine?
Tyrosine
What are the 3 stop codons
UAA UGA UAG "U Are Annoying, U Go Away, U Are Gone"
_______ is characterized by numbness of the fourth and fifth digits, pain, and weakness. It is most commonly caused by compressive injury, leading to tissue ischemia and demyelination ( _____ injury).
Ulnar neuropathy Schwann cell - A nerve conduction study can help differentiate demyelinating versus axonal neuropathies; demyelination causes slowed or blocked nerve conduction velocity whereas axonal injury leads to a reduction in signal strength.
O2 administration in a patient with COPD can lead to
V/Q mismatch - Supplemental oxygen administration in patients with chronic obstructive pulmonary disease can lead to increased CO2 retention (oxygen-induced hypercapnia), resulting in confusion and depressed consciousness. The major cause is reversal of hypoxic pulmonary vasoconstriction, which increases physiologic dead space as blood is shunted away from well-ventilated alveoli. - Several mechanisms contribute to oxygen-induced hypercapnia, but the major cause is increased ventilation-perfusion mismatch. Hypoxia causes vasoconstriction of the pulmonary arterioles, which acts to shunt blood toward alveoli with the highest ventilation, thereby minimizing physiologic dead space. Providing high-concentration supplemental oxygen allows lung regions with relatively poor ventilation to have higher oxygen levels, reversing pulmonary vasoconstriction. The redistribution of blood flow away from well-ventilated alveoli leads to an increase in physiologic dead space (well-ventilated alveoli are less perfused) with a corresponding reduction in CO2 excretion.
What is the mechanism of hypoxemia is a pulmonary embolism?
V/Q mismatch - only type of increased A/a gradient that is not fixed by O2 administration is shunt - normal A/a gradients fixed with O2 supplementation too
______ is the persistence of glandular columnar epithelium in the vagina and is a precursor for clear cell adenocarcinoma of the vagina. Who is at increased risk for it?
Vaginal adenosis Female offspring exposed to diethylstilbestrol in utero are at increased risk and may present with vaginal discharge or vaginal cysts/fleshy colored lesions.
What part of the Ig do antigens bind to?
Variable heavy and light chain (between them?)
________ causes smallpox, which is characterized by a vesiculopustular rash with lesions at the same stage of development. Moreover, smallpox has been eradicated due to vaccination.
Variola virus
-complication of vaccine administration in adolescents - skin findings (pallor vs urticaria) -absence of respiratory symptoms (eg, upper airway edema, bronchospasm) - presence of bradycardia (vs tachycardia).
Vasovagal syncope - stress-induced cardio-inhibitory and vasodepressor response - anaphylaxis = urticaria, tachycardia, and has respiratory symptoms
______ should be suspected in patients with new or worsening back pain, fever, and recent endocarditis or bacteremia (especially Staphylococcus aureus). It should also be suspected if there are new neurologic findings and fever with or without back pain. ______ is preferred for diagnosis.
Vertebral osteomyelitis MRI of the spine - CT myelogram, which can diagnose spinal stenosis or other vertebral pathology (including osteomyelitis), is performed by injecting contrast into the lumbar spine prior to CT imaging. However, it is more invasive than MRI and usually reserved for patients who cannot undergo MRI (eg, those with pacemaker, metallic implants).
_________- can be a complication of prostatectomy or bladder surgery. It predisposes to pyelonephritis and hydroureteronephrosis.
Vesicoureteral reflux
Patients with hemochromatosis are at increased risk for fulminant ______ infections (the organism is dependent on free iron for growth).
Vibrio vulnificus [also Listeria and Yersinia] - Although V vulnificus can cause rapid-onset sepsis and bullous skin lesions, it is a gram-negative bacterium. In addition, most infections occur due to shellfish consumption or wound contamination with seawater.
___________ produce dextrans that aid them in colonizing host surfaces, such as dental enamel and heart valves. These organisms cause subacute bacterial endocarditis, classically in patients with preexisting cardiac valvular defects after dental manipulation.
Viridans streptococci
Exclusively breast fed infants should receive what supplementation?
Vitamin D (to prevent rickets) - The breast milk content of vitamins D and K is typically insufficient for the nutritional needs of the newborn. Vitamin K is given parenterally to all newborns at birth to prevent hemorrhagic disease of the newborn. Exclusively breastfed infants require vitamin D supplementation due to lack of sunlight exposure and to prevent rickets.
________ is a common condition characterized by the loss of epidermal melanocytes. It occurs more commonly in patients with___________ and results in well-defined, variably sized patches of hypopigmentation.
Vitiligo autoimmune disorders (eg, autoimmune thyroiditis, type I diabetes)
_________ is an autosomal dominant condition characterized by the presence of capillary hemangioblastomas in the retina and/or cerebellum, as well as congenital cysts and/or neoplasms in the kidney, liver, and pancreas.
Von Hippel-Lindau disease
- Sinus (perforation of nasal septa, sinusitis, otitis media, mastoiditis) - Kidneys (hematuria, RBC casts) - Lungs (hemoptysis, cough, dyspnea) - c-ANCA
Wegeners
The presence of acute-onset asymmetric flaccid paralysis, particularly if the patient demonstrates concurrent parkinsonian features (eg, rigidity, bradykinesia, tremor, postural instability), is highly suggestive of _________ .
West Nile Virus - Diagnosis can be made when compatible clinical findings are associated with positive cerebrospinal fluid anti-WNV antibodies (polymerase chain reaction testing often not needed). - WNV is a positive-sense, single-strand RNA flavivirus transmitted by female mosquitoes (Culex spp), most commonly in the summer in warmer regions (eg, southern United States, Latin America, Africa). - Most WNV infections are asymptomatic or present with a flu-like illness (ie, West Nile fever: fever, headache, myalgias), often with a maculopapular or morbilliform rash on the back and chest.
________ is harbored in birds and transmitted to humans by mosquitos. Most patients are asymptomatic, but the virus can cause an influenza-like illness or neuroinvasive disease with meningitis, encephalitis, and flaccid paralysis.
West Nile virus - *contrast*: Nonpolio enteroviruses (eg, Coxsackievirus, echovirus) often cause aseptic (viral) meningitis and can occasionally cause encephalitis. However, these viruses are not associated with bird vectors and do not typically cause lower-motor neuron signs.
Diagnostic for candida vaginitis?
Wet mount examination with potassium hydroxide (KOH) preparation is diagnostic and reveals budding yeast and pseudohyphae. - In addition to "thick, white" vaginal discharge, patient will have vulvovaginal erythema and pruritus; and pseudohyphae on wet mount microscopy. - Treatment is with an antifungal medication (eg, fluconazole). - Vaginal pH is typically unchanged. - Elevated pH of vaginal secretions (>4.5) is associated with bacterial vaginosis and Trichomonas vaginitis
Mitral stenosis is loudest when?
When the mitral valve opens
When does the snap in mitral stenosis [rumbling diastolic murmur] occur (what part of the cardiac cycle)?
When the mitral valve opens "opening snap"
Melanoma lesions often have multiple color variations. The different colors represent different activities within the tumor. ____ areas occur when cytotoxic T cells recognize tumor antigens and destroy malignant cells, leading to *melanocyte regression*. ____ areas arise due to *vessel ectasia and local inflammation* _____ areas are generally due to *advancing malignant melanocytes*
Whitish/gray Red Brown or Black
_______ can present in childhood or adolescence with abnormal liver function tests and/or neuropsychiatric symptoms.
Wilson disease - Psychiatric symptoms may predate other manifestations and include personality changes, depression, mania, and/or psychosis. - *Contrast*: Prodromal schizophrenia often presents with personality changes and social withdrawal prior to the onset of overt psychosis. However, because primary psychotic disorders in children and adolescents are rare, a thorough workup of substance-induced and other etiologies is necessary.
Hep Serologic Status: Anti-HBe, Anti-Hbc IgM
Window period
- Male infant - recurrent infections - Eczema - Thrombocytopenia - low or abnormal platelets (bleeding, petachiae)
Wiskott-Aldrich Syndrome
Ventricular pre-excitation is seen in which condition
Wolff-Parkinson-White syndrome
Lymphatic filariasis is a mosquito-borne illness caused by roundworms (eg, _______ ). Most patients are infected in childhood and remain asymptomatic, but a minority develops chronic lymphedema, which may result in elephantiasis. Eggs are not present in stool; diagnosis is made by serology or by identifying worms in the lymphatic system.
Wuchereria bancrofti
Rett syndrome inheritance and gene mutation
X-linked dominant or Sporadic X-linked disorder MECP2 gene
Duchenne and Becker Muscular Dystrophy inheritance
X-linked recessive
Wiskott-Aldrich syndrome inheritance pattern/whats effected
X-linked recessive (male infants common) WAS gene/protein
Since Ankylosing Spondylitis doesn't have rheumatoid factor, what can be used to confirm the diagnosis?
X-rays - there are no serologic tests to confirm the diagnosis. Although most cases are associated with human leukocyte antigen B27 (HLA-B27), most patients with HLA-B27 never develop AS, so this marker does not confirm the diagnosis - X-ray of the pelvis shows inflammatory arthritis of the sacroiliac joints (ie, sacroiliitis), visible as joint erosions with subchondral sclerosis. These findings are relatively specific for spondylarthritis (including AS) and, in association with typical symptoms, are often adequate for diagnosis. As the disorder progresses, the joint space is obliterated, leading to bony fusion (ankylosis). - Spinal x-ray may show heterotopic ossification affecting the margins of the vertebral bodies, which are visible as bridging syndesmophytes. Advanced and continuous syndesmophyte formation is termed bamboo spine. - AS is characterized by bony erosions and excessive formation of new bone in the axial skeleton, primarily around the vertebral margins.
__________ , a bacteria transmitted by animal (eg, rodent) fleas, can cause bubonic plague, which typically presents with sudden-onset, flulike symptoms followed by intense pain and regional lymphadenopathy (eg, inguinal).
Yersinia - Yersinia grows well on traditional culture media; it appears on Gram stain as a gram-negative coccobacillus. What
Fibromuscular dysplasia causes renal artery stenosis, resulting in refractory hypertension. It typically occurs in ________
Younger women (age <50) - histology characteristically shows fibromuscular ridges alternating with areas of aneurysmal dilation affecting the main renal artery. - Over time, renal atrophy may occur due to chronic oxygen and nutrient deprivation. Histologic examination may show crowded glomeruli, tubulointerstitial atrophy and fibrosis, and focal inflammatory infiltrates.
Which NRTI can cause anemia?
Zidovudine
_____ deficiency causes erythematous skin lesions (mainly around body orifices) that are predominantly vesicular and pustular. Other features include hypogonadism, impaired taste and smell, night blindness, and impaired wound healing.
Zinc
Dubin-Johnson syndrome is
a benign, inherited disorder of bilirubin metabolism characterized by defective hepatic excretion of bilirubin into the biliary system. Bilirubin conjugation is normal, but defective excretion results in increased hepatocyte storage of bilirubin, resulting in dense liver pigmentation. Although patients often have recurrent episodes of scleral icterus, elevated direct bilirubin is expected due to reflux of conjugated bilirubin back into the plasma.
The primary virulence factor of Streptococcus pneumoniae is _____ that _______ .
a polysaccharide capsule inhibits opsonization and phagocytosis - The polysaccharide capsule of the most virulent strains is targeted by the pneumococcal vaccine, which confers immunity against those subtypes. - *Other virulence factors of S pneumoniae include IgA protease (inactivates secretory IgA), adhesins (necessary for adhesion to epithelial cells), and pneumolysin (cytotoxin that causes pores in cell membranes and cell lysis).* - S pneumoniae is a gram-positive diplococci that exhibits partial (α) hemolysis on blood agar (green colonies) and is bile-soluble and Optochin-sensitive. Its major virulence factor is a thick polysaccharide capsule that encases the organism and prevents phagocytosis and complement binding. Under the microscope, the capsule swells and appears as a halo around the blue-stained bacterial cells when specific anti-capsular antibodies and methylene blue dye are added ("quellung reaction").
Carpal tunnel syndrome is a peripheral neuropathy characterized by pain/paresthesias in a median nerve distribution (palmar surface of the first 3 digits and radial half of the 4th digit), weakness on thumb __________ , thenar atrophy, and a positive Tinel and/or Phalen test.
abduction/opposition
What is tricuspid atresia and what is the resultant O2 pattern?
absent communication between the RA and the RV - an atrial septal defect (ASD) is always present, allowing deoxygenated blood to flow from the RA to the LA. - --> This decreases SaO2 in the LA, LV, and systemic circulation, causing neonatal cyanosis. The little blood that reaches the lungs usually does so through a VSD, causing a relative increase in RV SaO2. [*therefore increased RV O2, but decreased O2 everywhere else*]
________ is an autosomal dominant disorder characterized by severely restricted chondrocyte proliferation in growth plate cartilage and decreased endochondral ossification.
achondroplasia [inhibition of cartilagenous growth due to decreased endochondral ossification]
fever, dysuria, and prostatic tenderness, consistent with ________
acute bacterial prostatitis (ABP) - Most commonly caused by reflux of urine and organisms from the bladder and urethra into the prostatic ducts, although it can occasionally be caused by direct inoculation (eg, prostate biopsy) or hematogenous seeding from remote infection (eg, endocarditis). - The risk of developing ABP is greater in patients with diabetes mellitus, anatomic abnormalities (eg, strictures), or bladder catheterization. - As with other urinary tract infections, the most common organisms in ABP include enteric gram-negative bacilli, predominantly *Escherichia coli*, because of virulence factors (eg, adhesins on bacterial fimbriae) that allow it to adhere onto mucosal or urothelial cells. - The other bacteria (also gram-negative bacilli) that commonly cause ABP include Proteus, Klebsiella, Pseudomonas.
Both dermatomyositis and polymyositis may occur alone or as a paraneoplastic syndrome associated with an underlying _______
adenocarcinoma (eg, ovary, lung, pancreas) - Dermatomyositis is characterized by proximal muscle weakness resembling polymyositis, with additional inflammatory features involving the skin (heliotrope rash, Gottron papules).
Enlarged uterus is seen in
adenomyosis (normal size = endometriosis)
Replacement of one type of epithelium with another type not typical for location is called metaplasia. Unlike ectopia, which is the result of congenital malformation, metaplasia occurs during ______ and is initially a compensatory process. Metaplasia increases cancer risk in varying degrees.
adult life - if child, think ectopia - A number of ectopic tissues are found in Meckel diverticulum−most commonly, gastric epithelium. Gastric mucosa is present in 80% of cases of symptomatic Meckel diverticulum. Gastric acid production leads to ulceration and subsequent bleeding.
Histologic findings in _________ include lobular *neutrophilic* infiltrates, steatosis, *ballooning of hepatocytes*, and formation of *Mallory-Denk bodies (eg, cytoplasmic eosinophilic inclusions within hepatocytes)*.
alcohol-induced liver disease - aminotransferase elevations are modest and rarely exceed 300 U/L, usually with an AST/ALT ratio >2:1
C perfringens classically causes gas gangrene (eg, necrosis, gas in tissue) within hours of infection. This is primarily mediated by the generation of ______ , a potent ______ mimetic that splits host _______ .
alpha toxin (lecithinase) phospholipase C phospholipids - This compound hydrolyzes lecithin-containing lipoprotein complexes in cell membranes, which causes cell lysis, tissue necrosis, and edema. It also mediates intravascular aggregations of platelets, neutrophils, and fibrin, which results in vascular occlusion and further promotes the anaerobic environment required for bacterial proliferation. - C perfringens is an obligate anaerobic, spore-forming, gram-positive rod found in soil. Most cases develop following the introduction of spores into tissue during penetrating injury (eg, knife wound, puncture wound); significant vascular damage is generally required to create the anaerobic environment necessary for vegetative bacterial proliferation.
Fetal hemoblobin
alpha-2 - gamma 2
*Autoactivation of C3b* triggers the ______ complement pathway, which is marked by
alternative - normal C4, - low C3 and factor B levels - AH50, a measure of functional activity of the alternative pathway, will also be low.
Respiratory distress syndrome classically presents in premature infants with increased work of breathing and hypoxia at birth due to surfactant deficiency. Poor ______ leads to widespread atelectasis and decreased _______ . Airway resistance is often __(increased/decreased)__ due to lung inflammation and edema.
alveolar compliance functional residual capacity increased - Without surfactant, the alveoli have increased surface tension and therefore decreased compliance. These poorly compliant alveoli are prone to collapse, resulting in widespread atelectasis that lowers functional residual capacity and total lung capacity. Surfactant deficiency also results in pneumocyte injury and lung inflammation; the resulting edema can narrow the airways and increase airway resistance
Antibiotic-modifying enzymes add chemical groups (eg, acetyl, adenyl, phosphate) to a target drug and are the most common mechanisms of _________ resistance.
aminoglycoside (eg, gentamicin)
Paradoxical embolism occurs when a thrombus from the venous system crosses into the arterial circulation via
an abnormal connection between the right and left cardiac chambers (eg, patent foramen ovale, atrial septal defect, or ventricular septal defect).
Patients with ________ are genetically male but have a female phenotype due to resistance to testosterone. In adolescence, breast development results from peripheral conversion of testosterone to estrogen, but axillary and pubic hair is absent. Primary amenorrhea occurs due to a complete absence of Müllerian structures.
androgen insensitivity syndrome
In patients with undiagnosed pheochromocytoma, induction of _______ can precipitate a catecholamine surge, leading to hypertensive crisis, flash pulmonary edema, and atrial fibrillation.
anesthesia (eg, preparation for thyroidectomy)
Leptospirosis is a zoonotic infection caused by the motile spirochete and transmission primarily occurs when humans come into contact with water contaminated with _________ during outdoor recreational or occupational activities.
animal urine
Epistaxis is commonly caused by irritation of the highly vascular mucosa at the _______ , which contains the Kiesselbach plexus.
anterior nasal septum - The anterior ethmoidal, sphenopalatine, and superior labial arteries anastomose in this region.
What antibody is specific for systemic sclerosis?
anti-topoisomerase (Scl-70) [and anti-RNA polymerase 3?]
In N gonorrhea, through _________ , each gonococcus can modify the pilus protein expressed, thereby avoiding host defenses (to some degree) and making vaccination directed against the pilus protein difficult.
antigenic variation
The brachiocephalic artery branches from the _______ , then divides into the _______ arteries.
aortic arch right subclavian and right common carotid
decrescendo diastolic murmur
aortic regurg
Where is type 2 collagen found?
articular and hyalin cartilage
Defect in filagrin is seen in
atopic dermatitis (eczema)
The area around the opening of the pulmonary veins in the left atrium is frequently involved in the pathogenesis of _______
atrial fibrillation
pH and whiff tests can be used to diagnose ______ , which typically presents with *thin, off-white, malodorous discharge with no associated vaginitis*.
bacterial vaginosis - Bacterial vaginosis is associated with a grayish-white, malodorous vaginal discharge due to an overgrowth of Gardnerella vaginalis, a facultative anaerobic, gram-variable rod. *Clue cells* (squamous *epithelial cells covered with bacterial organisms*) are seen on wet mount microscopy or cytology. - In bacterial vaginosis, the addition of potassium hydroxide (KOH) to the vaginal discharge releases amines, causing a characteristic odor (eg, positive whiff test). - Vaginal pH is elevated in both bacterial vaginosis and trichomonas infection; therefore, pH testing is not specific for diagnosis.
blood supply to medial part of pons
basilar artery
What drug is used for immediate symptom relief in Hyperthyroidism?
beta blockers (doesn't treat exophthalmos)
where does blood accumulate in subdural hematoma
between dura and arachnoid membrains
where does blood accumulate in epidural hematoma
between dura and skull
In Wilsons Disease, there is defective hepatocyte transport of copper into ______ for excretion
bile - Defective incorporation of copper into apo-ceruloplasmin to form ceruloplasmin (binding protein for copper in blood) - The excess copper promotes free radical formation that results in oxidation of lipids and proteins - In general, dietary copper is absorbed in the stomach and duodenum and bound to circulating albumin. It is then transported to the liver and taken up by hepatocytes. - Excessive intracellular copper levels normally cause ATP7B to transfer the excess copper into the bile canaliculi. This process is essential for biliary excretion of copper, which accounts for the majority of total body copper excretion. - In Wilson disease, defective ATP7B results in impaired biliary excretion of copper. The accumulation of hepatocellular copper results in oxidative stress and apoptosis. - Upon cell death, free copper is released into the bloodstream and deposited into extrahepatic tissues (eg, basal ganglia, cornea), causing the classic triad of hepatic, neurologic, and psychiatric (eg, depression) symptoms.
Risk factors for pancreatitis include
biliary disease, chronic alcohol use, and hypertriglyceridemia.
A hypertensive patient's kidneys receive less _______ at any given BP relative to those of a healthy patient without hypertension.
blood flow - Quickly lowering the BP to normal (eg, 231/135 --> 145/95 mm Hg) causes a steep drop in blood flow, leading to ischemic ATN; as a result, BP should be lowered gently, targeting above-normal values (eg, 25% reduction over several hours). - Normally in High BP: high arterial pressure causes hyperfiltration (↑ glomerular filtration rate), increasing sodium and chloride delivery to the macula densa, which secretes vasoactive mediators (eg, adenosine) to constrict the afferent arterioles. Also, Afferent glomerular arterioles reflexively constrict when they sense greater stretch forces (high BP) [myogenic response]
Erythropoiesis occurs in what part of the bone?
bone marrow [elderly have increased bone marrow fat and decreased bone marrow mass --> decreased erythropoiesis] - Patients with advanced age generally have *increased (not decreased) medullary cavity* size due to loss of endosteal cortical bone. This increases the risk of *fractures*.
Conduction system fibrosis (often age-related) is a primary contributor to
bradyarrhythmias, including sinus bradycardia (eg, sick sinus syndrome) and atrioventricular block.
the most common cancers (excluding basal and squamous cell skin cancer) in *women* by order of incidence are
breast, lung, and colorectal cancer. - In terms of mortality, lung cancer claims the most lives, followed by breast and colorectal cancer.
The ______ forms the beginning of the ventricular outflow tract in the embryonic heart. This structure forms the smooth portions of the left and right ventricles adjacent to the aorta and pulmonary artery, respectively.
bulbus cordis
The most common eye-related complication of congenital cytomegalovirus infection is _______ .
chorioretinitis
Individuals on a vegan diet are commonly deficient in _____ , _____ , ______ , and _____ and may require supplementation.
calcium, vitamin D, vitamin B12, and iron
Episodes of presyncope (eg, lightheadedness, feeling of impending loss of consciousness) that occur when he adjusts his shirt collar or necktie most likely has _______.
carotid sinus hypersensitivity (CSH) - The condition results from overly sensitive carotid baroreceptors that stimulate an excessive vasovagal response to tactile stimulation. --> *decreased systemic vascular resistance* - Most commonly seen in *elderly men*; *underlying carotid atherosclerotic disease and prior neck surgery (eg, thyroidectomy)* are risk factors. - The baroreceptor response in CSH mimics the normal response to increased blood pressure but is more exaggerated; increased parasympathetic output leads to a *prolonged sinus pause* (eg, 3-5 seconds) and decreased sympathetic outflow causes marked peripheral vasodilation. - --> The resulting delay in ventricular contraction and decreased systemic vascular resistance leads to a profound reduction in blood pressure and transient loss of cerebral perfusion that manifests as presyncope or syncope.
CSF flows from the third ventricle to the fourth ventricle via the _______ . Obstruction at this level can cause dilated lateral and third ventricles with a *normal-sized fourth ventricle*
cerebral aqueduct of Sylvius
intussusception is most common in what age group
children less than 2 - may have electrolyte derangement - Clinical presentation is colicky, intermittent abdominal pain, nausea, vomiting, and "currant jelly" stools (that contain blood and mucus). - A tubular mass may be palpable in the lower right abdominal quadrant. - Barium enema is diagnostic and may be therapeutic. If the intussusception does not resolve with barium enema, surgical intervention is mandated. - In patients older than 2 years of age, a lead point, such as Meckel diverticulum, foreign body, or intestinal tumor, should be sought.
Total body ______ depletion is often important in the pathophysiology of *metabolic alkalosis*.
chloride - Measurement of urine chloride can be helpful in determining the underlying etiology.
Hemosiderin-laden macrophages ("heart failure cells") form as macrophages digest red blood cells that leak from alveolar capillaries damaged by high intravascular pressure. They are a sign of __________
chronic lung congestion - would not be present acutely (i.e. acute heart failure) - *contrast*: Acute pulmonary edema is a common consequence of acute myocardial infarction affecting the left ventricle. Elevated hydrostatic pressure in the pulmonary venous system leads to engorged alveolar capillaries with transudation of fluid into the alveoli, appearing as acellular pink material on microscopy.
Disruption of the thoracic lymphatic duct is an occasional cause of malignant effusion that leads to a _______ . This mechanism is most commonly seen with _______
chylothorax (milky white pleural fluid with high triglyceride content) lymphoma
Adults with ________ often have chronic hypertension and are at increased risk of developing life-threatening aneurysms of the aorta (eg, dissection, rupture) and cerebral vessels (ie, intracranial hemorrhage).
coarctation of the aorta - can be associated with Turner syndrome or bicuspid aortic valve (which is also associated with Turner syndrome) - Coarctation of the aorta is a narrowing of the aortic arch near the ligamentum arteriosum (remnant of ductus arteriosus) with localized medial and intimal hyperplasia. Critical coarctation (severe narrowing) often presents in the neonatal period with heart failure and cardiogenic shock. However, less severe narrowing allows for distal (but decreased) perfusion to the lower extremities and may present with only asymptomatic upper extremity hypertension in children or adults. Additional symptoms due to this differential in blood pressure include headache, epistaxis, chest pain, and lower extremity claudication. - Complications of aortic coarctation include cerebral and aortic aneurysm. Cerebral aneurysm with life-threatening rupture causing subarachnoid hemorrhage is likely due to chronic hypertension. Aortic aneurysms usually develop near the site of coarctation due to embryologic vessel wall abnormalities and may lead to dissection or fatal rupture.
The hepatitis B surface antigen of hepatitis B virus must _____ the hepatitis D antigen of hepatitis D virus before it can infect hepatocytes and multiply.
coat
Constipation is common during pregnancy and results from the inhibitory effect of progesterone on ...
colonic smooth muscle contractions/contractions (and the fasting migrating myoelectric complex)
The _________ is the continuation of the external iliac artery as it crosses the inguinal ligament
common femoral artery - The optimal site for obtaining vascular access in the lower extremity during cardiac catheterization is the common femoral artery below the inguinal ligament. Cannulation above the inguinal ligament can significantly increase the risk of retroperitoneal hemorrhage.
Hypertensive damage to kidneys can result in hyperplastic arteriosclerosis, which can be described as
concentric layers of collagen and proliferating smooth muscle --> onion skin appearance --> reduced RPF and filtration --> activation of RAAS --> further increase in BP
Pneumococcal ______ vaccines are strongly immunogenic in infancy due to both B and T cell recruitment. They provide higher, longer-lasting antibody titers relative to pneumococcal ______ vaccines.
conjugate polysaccharide - The pneumococcal polysaccharide vaccine is poorly immunogenic in infants due to their relatively immature humoral antibody response. - Conjugate < 55 yo - Polysaccharide > 2 yo
In pathology, increased breath sounds are only seen in _______ In pathology, increased tactile fremitus is only seen in ______
consolidation consolidation [consolidation = dullness to percussion; resonance = normal; hyper-resonance = pneumothorax only] [normal breath sounds only seen in normal lung]
What part of the immunoglobulin binds to phagocytes to help initiate the classical complement cascade?
constant region of the heavy chain
Non-typhoidal Salmonella, a motile gram-negative bacillus, is often transmitted via the ingestion of
contaminated poultry
What is used to treat Graves ophthalmoplagia?
corticosteroids/glucocorticoids
What kind of cells secrete ACTH?
corticotrophs
Stress-induced hyperglycemia and insulin resistance can occur in times of acutely increased metabolic demand (eg, trauma, burn, sepsis) due to the release of
cortisol, epinephrine, and glucagon.
The absence of normal enteral stimulation in patients receiving total parenteral nutrition leads to
decreased cholecystokinin release, biliary stasis, and increased risk of gallstones. - Resection of the ileum can also increase the risk of gallstones due to disruption of normal enterohepatic circulation of bile acids. - Cholesterol is secreted in bile, where it is solubilized by bile salts and phosphatidylcholine. If there is more cholesterol than can be dissolved by the bile salts, the cholesterol will precipitate into insoluble crystals, leading to the formation of gallstones. - Risk factors for gallstone formation include obesity or rapid weight loss, female sex, glucose intolerance, and hypomotility of the gallbladder (eg, pregnancy, prolonged fasting). - A prolonged course of total parenteral nutrition (TPN) is often complicated by gallstones. In normal individuals, enteral passage of fat and amino acids into the duodenum triggers release of cholecystokinin (CCK), leading to contraction of the gallbladder. The absence of normal enteral stimulation in patients receiving TPN leads to decreased CCK release and subsequent biliary stasis. - In addition, patients with extensive resection of the ileum can have disruption to the normal enterohepatic circulation of bile acids, leading to inadequate solubilization of biliary cholesterol and formation of cholesterol crystals.
In patients with advanced chronic kidney disease and diabetes mellitus, ________ can lead to symptomatic hypoglycemia...
decreased renal clearance of insulin ... if exogenous insulin doses are not adjusted based on the change in renal function - Insulin has both renal and hepatic clearance.
What cells produce somatostatin?
delta cells - Somatostatin (growth hormone-inhibiting hormone) is secreted by D cells of pancreatic islets and GI mucosa. It has multiple inhibitory effects over the GI tract, including decreasing motility, gastrin secretion, pancreatic endocrine/exocrine secretion, and absorption of nutrients.
Urticaria causes ______ edema
dermal - *lesions are transient and migratory*
In _________, there are deposits of IgA at the tips of dermal papillae/dermo-epidermal junction
dermatitis herpetiformis - associated with Celiac disease - erythematous pruritic papules, vesicles, and bullae that appear symmetrically on extensor surfaces
An individual with a point mutation affecting the gene responsible for *neurophysin* synthesis is most likely to suffer from _______
diabetes insipidus - Neurophysins are carrier proteins for oxytocin and vasopressin (antidiuretic hormone, ADH), hormones produced within the paraventricular and supraoptic nuclei, respectively, and released from the posterior pituitary. - Neurophysin II has a binding site specific for vasopressin and is thought to be involved in the transport and packaging of vasopressin through the endoplasmic reticulum (ER) and Golgi apparatus into neurosecretory granules. A point mutation in neurophysin II could result in abnormal protein folding and removal from the ER along with bound vasopressin, thereby decreasing availability of vasopressin for neurosecretory release.
Nodular glomerulosclerosis and mesangial expansion are seen on light microscopy in _______
diabetic nephropathy - which presents as a nephrotic syndrome. There are no immune deposits on immunofluorescence. - Nodular glomerulosclerosis = Kimmelstiel-Wilson lesion
C diff. causes disease by releasing 2 toxins that damage the mucosal lining of the large intestine, leading to _____ (toxin A) and ______ (toxin B) with pseudomembrane formation.
diarrhea necrosis [Toxigenic strains (Toxins A and B)] Secreted Exotoxins: TcdA and TcdB --> Effects: (multidomain structure) --> - A: Biologic Activity --Transfer glucose onto GTPases involved in regulation of cytoskeleton -> GTPase inactivation ---Cytopathic effect: *cytoskeletal breakdown* ---Cytotoxic effect: induction of cell death - B: Binding - C: Cutting Proteolytic cleavage of toxin - D: Delivery --...For endocytosis and translocation
With persistent tachycardia, ventricular ______ shortens
diastole - allowing less time for ventricular relaxation and filling. - Stroke volume and cardiac output decrease, leading to hypotension and poor peripheral perfusion. - Infants may become altered (eg, lethargic, poor feeding) and develop signs of heart failure (eg, tachypnea, crackles, hepatomegaly). - A large left-to-right intracardiac shunt (eg, ventricular septal defect [VSD]) can cause hypotension and tachycardia, but signs of heart failure (eg, crackles, hepatomegaly) would be expected. In addition, depending on the size of VSD, ECG may show left or biventricular hypertrophy, not narrow QRS complexes with absent P waves.
Pancreatitis is an important side effect of the HIV medication __________ , a nucleoside reverse transcriptase inhibitor.
didanosine
Hypersensitivity pneumonitis due to inhalation of agricultural dusts or bacteria (eg, farmer's lung) tends to result in ________
diffuse, nodular interstitial infiltrates
Carbon dioxide is a potent vaso_____ of cerebral vasculature.
dilator - Tachypnea (rapid respiratory rate) causes hypocapnia and cerebral vasoconstriction, thereby decreasing cerebral blood volume and intracranial pressure.
The primary treatment for diphtheria is
diphtheria antitoxin (passive immunization), which inactivates circulating toxin.
The left common carotid and left subclavian arteries branch from what?
directly from the aortic arch
In _________ , patients present with irritable mood + repetitive temper outbursts (verbal or physical) that are out of proportion to the stimulus and inconsistent with developmental level. Symptoms should manifest *prior to age 10*.
disruptive mood dysregulation disorder
Alcohol-based disinfectants, which are composed of ethyl or isopropyl alcohol (at concentrations of 60%-90%) in water, are often used for hand hygiene. These solutions kill vegetative bacteria (but not spores), fungus, and enveloped viruses (eg, influenza, HIV, herpes) by ________ and subsequently denaturing their proteins*.
dissolving their lipid bilayer membranes* - Nonenveloped viruses such as adenovirus, rhinovirus, enterovirus, and poliovirus are less susceptible to some alcohol-based disinfectants (particularly isopropyl-based solutions) because they do not have a lipid bilayer envelope.
Sharp pain and bright red rectal bleeding on defecation, suggesting an anal fissure. Anal fissures are due to stretching of the mucosa and are characterized by longitudinal tears in the anal canal where?
distal to the dentate line - Most fissures are related to chronic constipation with high anal pressures and passage of hard stools. - They can also be seen with frequent diarrhea or anal sexual intercourse. In some cases, the pain may be so severe that patients withhold bowel movements, thereby exacerbating the constipation. - Anterior midline fissures are less common, but may occur due to mechanical stresses related to the alignment of muscular fibers in the external sphincter
Wallenberg syndrome is due to ischemic injury to the _______ , which is supplied by the ______ artery, can result in what symptoms?
dorsolateral medulla posterior inferior cerebellar Symptoms: - Loss of pain/temperature over the ipsilateral face and contralateral body (due to damage of the spinal trigeminal [CN5] and spinothalamic tracts) - Ipsilateral bulbar muscle weakness (nucleus ambiguus; *hoarseness, dysphagia, decreased gag reflex*), vertigo (vestibular nuclei) - Ipsilateral limb ataxia (inferior cerebellar peduncle) - Horner syndrome (descending sympathetic fibers).
Anti-histone antibodies are found in ______
drug-induced lupus - It has been linked to drugs metabolized by N-*acetylation in the liver* (eg, procainamide, hydralazine, isoniazid). - Genetically predisposed individuals who are slow acetylators are at greater risk for developing DILE.
Adenovirus genome
dsDNA non-enveloped
Entamoeba histolytica is an ameba that causes ______ . Histopathology generally reveals flask-shaped colonic ulcers with _____
dysentery (bloody diarrhea) "foamy" trophozoites that resemble macrophages.
Xeroderma pigmentosum is an autosomal recessive disorder characterized by defective nucleotide excision repair often caused by a deficiency in UV-specific ______ .
endonuclease - Affected children usually have severe photosensitivity, hyperpigmentation in sun-exposed areas, and a greatly increased risk for skin cancer. - This boy with severe photosensitivity, poikiloderma, hyperpigmentation in sun-exposed areas, and squamous cell carcinoma of the skin has xeroderma pigmentosum, an autosomal recessive disorder characterized by defects in nucleotide excision repair. DNA can be damaged by ultraviolet rays, leading to formation of thymine dimers between 2 adjacent thymine residues. - These thymine dimers are repaired by UV-specific endonuclease, an enzyme that is frequently deficient in patients with xeroderma pigmentosum. This enzyme recognizes distortions in the structure of DNA caused by thymine dimers and subsequently excises stretches of single-stranded DNA that contain these defects. The gap created following this excision is then filled by DNA polymerase, which uses the opposite DNA strand as a template. The new strand of DNA is then joined on both ends to the existing DNA by the enzyme ligase.
Infantile hemangiomas are benign vascular tumors composed of proliferating _____ cells that most frequently affect the head or neck region.
endothelial - Natural history of these lesions involves rapid growth of a red, cutaneous plaque followed by spontaneous regression.
Vasospastic angina (Prinzmetal) is the result of intermittent coronary vasospasm caused by _____ dysfunction and autonomic imbalance.
endothelial - leads to intermittent coronary vasospasm and myocardial ischemia. - Affected patients are usually young (eg, age <50) and lack typical risk factors for coronary artery disease (CAD) (eg, hypertension, diabetes mellitus); however, *smoking is a strong risk factor*, likely because it contributes to endothelial dysfunction. - Symptoms of vasospastic angina are thought to be triggered by excess vagal tone, and they occur most commonly at night when vagal tone is at a peak. - Because of the pathophysiology of the disorder, both acetylcholine and ergot alkaloids (eg, dihydroergotamine) provoke symptoms and may also aid in diagnosis as follows: -- Acetylcholine normally stimulates endothelial muscarinic receptors to cause vasodilation via increased release of nitric oxide. However, a deficiency of endothelial nitric oxide in affected patients causes increased vagal tone to instead trigger vasoconstriction and precipitate vasospastic symptoms. -- Ergot alkaloids activate 5-HT2 serotonergic receptors to cause vasoconstriction. Normally, the vasoconstriction is somewhat offset by endothelial release of vasodilatory prostaglandins, but this response is lacking in affected patients due to endothelial dysfunction.
Mutations of the HIV _____ gene enable escape from host-neutralizing antibodies.
env
Rupture of middle meningeal artery
epidural hematoma (lens shaped; biconvex) - pt may get transtentorial (uncal) herniation
Linear growth stops when the
epiphyseal growth plate closes, - i.e. when the epiphysis fuses with the metaphysis. - Sex steroids initially increase linear growth, but they also encourage closure of epiphyseal growth plates. - Sex hormones promote both growth and epiphyseal plate closure; hence, precocious puberty may result in a shorter stature, despite an initial growth spurt. Gigantism is caused by excessive pituitary production of growth hormone; these patients achieve enormous heights because, unlike excessive sex steroids, excessive IGF-1 does not lead to premature closure of the epiphysis.
Scarlet fever is caused by the body's response to an _______ released by group A Streptococcus.
erythrogenic (pyrogenic) toxin - It presents with a diffuse, erythematous, "sandpaper"-textured rash most notable in the skin folds (eg, inguinal, axillary, antecubital areas). - Scarlet fever can occur with pharyngitis and can lead to acute rheumatic fever if untreated. Strep super antigen = pyrogenic exotoxin - Inhibits production of Abs - Stimulate T cells to increase inflammatory cytokines - Seen in Scarlet fever and Strep Toxic Shock Syndrome
Erythema infectiosum (fifth disease) is caused by parvovirus B19 and presents with a nonspecific prodrome (eg, malaise, fever, congestion) followed by a classic "slapped-cheek" facial rash and a lacy, reticular body rash. Parvovirus is highly tropic for ________ and replicates predominantly in the ________ .
erythroid precursor cells [erythrocyte P receptor] bone marrow
Wolff-Chaik*off* effect—
excess iodine temporarily turns *off* thyroid peroxidase--> decreased T3/T4 production (protective autoregulatory effect).
Primary herpes simplex virus type 1 (HSV-1) infection in children causes _______
gingivostomatitis --> vesicular lesions on the lips, gums and hard palate
What lipid lowering agent can increase Liver Function Tests?
ezetimibe
Failure of the PT to correct with vitamin K supplementation indicates _______ , which is often due to underlying liver disease.
factor VII deficiency - Vitamin K-dependent coagulation factors (II, VII, IX, and X) are synthesized in the liver. Factor VII has the shortest half-life of the coagulation factors.
Fat globules and bone marrow cells in the pulmonary arterioles occur with ________
fat embolism syndrome - not a complication of MI but is typically associated with long bone (eg, femur) or pelvic fracture.
Viridans streptococci are normal inhabitants of the oral cavity and are a cause of transient bacteremia after dental procedures in healthy and diseased individuals. In patients with pre-existing valvular lesions, viridans streptococci can adhere to ________ and establish infection that leads to endocarditis.
fibrin-platelet aggregates
Characteristic pathology findings of fibromuscular webs alternating with aneurysmal dilation and loss of the internal elastic lamina, is consistent with __________
fibromuscular dysplasia (FMD) - abnormal tissue growth within arterial walls, leading to arterial stenosis, tortuosity, aneurysms, or dissections. - Women age <55. - Angiography (ie, percutaneous, CT, MRI) is diagnostic and typically demonstrates a *string-of-beads* appearance in multifocal disease.
Patients with Renal Cell Carcinoma classically have a triad of
flank pain, palpable mass, and hematuria - Can invade the renal vein and IVC
Obstruction at the _______ causes enlargement of all 4 ventricles
foramen of Magendie and Luschka
Obstruction at the ______ would cause enlargement of only the affected lateral ventricle
foramen of Monro
Type 2 diabetes mellitus is due to insulin resistance and relative insulin deficiency. Chronically elevated _______ levels contribute to insulin resistance by impairing insulin-dependent glucose uptake and increasing hepatic gluconeogenesis.
free fatty acid - Other factors that contribute to insulin resistance include obesity and a sedentary lifestyle - elevated LDL and HDL levels do not contribute to insulin resistance or acanthosis nigricans [a sign of insulin resistance]
*Positive end-expiratory pressure* helps treat *acute respiratory distress syndrome* by opening collapsed alveoli to *reduce intrapulmonary shunting* and increase ___________.
functional residual capacity (FRC) - The increased FRC decreases ventilation-perfusion mismatching and increases the oxygen reserves in the lungs. - Mechanical ventilation is typically needed for the management of ARDS because it allows for the application of positive end-expiratory pressure (PEEP). PEEP helps treat ARDS by opening collapsed alveoli to reduce intrapulmonary shunting and increase FRC back to near-normal levels. - PEEP increases, rather than decreases, alveolar pressure - Intrapleural pressure is normally negative throughout the respiratory cycle due to the opposing elasticity of the lungs (tend to collapse) and chest wall (tends to expand). Increased end-expiratory airway pressure during PEEP reduces the collapsing force of the lungs, causing the intrapleural pressure to increase. - Prone positioning may be used to improve arterial oxygenation in patients with severe acute respiratory distress syndrome. The improvement likely results from reduced compression of the posterior lung segments, where the majority of alveoli are located. This leads to more evenly distributed ventilation throughout the lungs with reduced intrapulmonary shunting and *improved ventilation-perfusion matching*.
Diagnose with ultrasound or cholescintigraphy (HIDA scan). Failure to visualize _______ on HIDA scan suggests _________
gallbladder obstruction or acute cholecystitis - Acute cholecystitis is most often caused by gallstones obstructing the cystic duct. The diagnosis can be made by identifying signs of gallbladder inflammation (eg, wall thickening, pericholecystic fluid) on ultrasonography. When ultrasound is inconclusive, nuclear medicine hepatobiliary scanning (ie, cholescintigraphy) can be used to assess cystic duct patency and make the diagnosis. - Acute cholecystitis is caused by gallstone obstruction of the cystic duct in more than 90% of cases. Ingestion of fatty foods then stimulates contraction of the gallbladder against the impacted stone, resulting in severe colicky pain. - Mechanical disruption of the gallbladder mucosa and release of inflammatory mediators (eg, lysolecithin, prostaglandins) cause the obstructed gallbladder to become inflamed and edematous. As blood supply to the distended organ becomes compromised, secondary bacterial infection frequently develops. Potential complications include gangrene and perforation, with subsequent formation of a pericholecystic abscess or generalized peritonitis.
In diabetic nephropathy, early adaptive changes in the kidney cause a transient increase in _______ . As diabetic nephropathy progresses, glomerular filtration falls, with a concurrent increase in urine _____ loss.
glomerular filtration (hyperfiltration) albumin
What is the first functional change of diabetic nephropathy?
glomerular hyperfiltration [comes before the albuminuria]
Helicobacter pylori is a common cause of peptic ulcers. *Duodenal ulcers* are associated with heavy colonization in the _______ , whereas colonization in the ________ is associated with *gastric ulcers*.
gastric antrum gastric corpus - Colonization of H pylori in the gastric antrum is associated with decreased somatostatin formation and increased gastrin secretion, which stimulate the parietal cells to produce excess acid. This results in an increased acid load emptying into the proximal duodenum, leading to duodenal ulcer (DU) formation. Biopsy of the antrum can confirm H pylori infection in patients with a DU, which characteristically presents with upper abdominal pain that improves with eating. - In contrast, gastric ulcers (GUs) are associated with colonization in the gastric corpus (body). The etiology of GUs is not acid related, as these patients typically have normal or reduced acid levels, but is thought to be due to direct mucosal damage and chronic inflammation. Unlike DU pain, GU pain often worsens with eating.
In patients with Zollinger-Ellison syndrome, _____ hypersecretion induces parietal cell hyperplasia, causing visible enlargement of gastric folds on endoscopy.
gastrin - The increased gastric acid secretion induced by excess gastrin also causes peptic ulcer disease, heartburn, and diarrhea. - Histamine, acetylcholine, and gastrin increase gastric acid secretion, but prostaglandins inhibit it. - Gastrin not only stimulates HCl secretion, but it also has a trophic effect on parietal cells. - Acetylcholine stimulates parietal cell acid secretion but is *not* typically associated with parietal cell hyperplasia or gastric fold enlargement.
Peptic ulcers involving the posterior duodenal bulb can erode into the ______ artery and cause bleeding.
gastroduodenal
The right paracolic gutter is a peritoneal recess found between the ascending colon and abdominal wall. Fluid (bile, pus, or blood) typically accumulates there from pathology involving the
gastrointestinal organs, particularly the appendix and gall bladder
The carotid sinus is a dilation of the internal carotid artery located just above the bifurcation of the common carotid artery. The carotid sinus reflex has an *afferent limb* that arises from the baroreceptors in the carotid sinus and travels to the vagal nucleus and medullary centers *via* the _______ nerve; the *efferent limb* carries parasympathetic impulses *via* the _________ nerve.
glossopharyngeal nerve (CN IX) vagus nerve (CN X)
Patients with type 1 diabetes mellitus are at increased risk of hypoglycemia because exogenous insulin will continue to be absorbed from the injection site despite falling glucose levels. Those with long-standing diabetes may also have decreased ________ secretion and therefore have an even greater risk of rapid hypoglycemia.
glucagon - Those with long-standing diabetes (ie, >5 years) frequently also have alpha cell failure with decreased glucagon secretion and therefore have an even greater risk of rapid hypoglycemia.
The ______ of the actinomycete Tropheryma whippelii colors magenta with PAS and is diastase-resistant, making this stain an excellent choice in evaluating tissue for Whipple disease.
glycoprotein in the cell walls - Diastase can be used in conjunction with PAS to demonstrate glycogen, which is found in skin, liver, parathyroid, and skeletal/cardiac muscle. The diastase works by digesting glycogen to form maltose and glucose, two sugars that are easily washed from sections during processing (therefore giving a negative reaction). - The glycoprotein present in the cell walls of the gram-positive actinomycete Tropheryma whippelii appears magenta with PAS and is diastase-resistant, which makes this stain an excellent choice when microscopically evaluating small bowel mucosa for Whipple disease. *Contrast*: - Calcium appears as a dark purple deposit on hematoxylin and eosin stain. - Iron appears blue with stains such as Prussian blue. - Neutral lipids can be identified with a multitude of stains, including Nile red or Sudan black (with the latter being useful for frozen sections).
The dimorphic fungus Sporothrix schenckii histologically appears as
granulomatous and neutrophilic inflammation - Stains for fungal organisms may highlight rare, cigar-shaped yeast
Secretion of _____ by testicular germ cell tumors impairs testosterone production in Leydig cells while increasing aromatase activity and conversion of androgens to estrogens.
hCG - The resulting increase in the estrogen/androgen ratio can cause gynecomastia.
Interferon-α is used for the treatment of
hairy cell leukemia, condyloma acuminata, hepatitis B virus infection Kaposi sarcoma. renal cell carcinoma Chronic Hep C (not preferred)
A ________ is an insurance plan with low monthly premiums, low copayments and deductibles, and low total cost for the patient.
health maintenance organization (HMO) - HMOs reduce utilization by confining patients to a limited panel of providers, requiring referral from a primary care provider prior to specialist consultations, and denying payment for services that do not meet established guidelines.
Metformin is contraindicated in patients with
heart failure (hypoxia) liver failure, alcohol abuse, renal insufficiency (check serum creatinine before prescribing) - More prone to lactic acid build up in blood - Side note: Metformin can cause B12 deficiency with long term use
rectosigmoid involvement in colon cancer causes
hematochezia (fever is UNCOMMON)
Aflatoxin exposure, which can occur after exposure to contaminated crops (eg, peanuts, corn), is a chemical risk factor associated with _________
hepatocellular cancer - although viral hepatitis, cirrhosis, and alcohol abuse are more common risk factors
Tzanck smear is used to diagnose
herpes simplex or varicella zoster virus infection - The epithelial cells scraped from the ulcer base are prepared with a Wright-Giemsa stain and examined for multinucleated giant cells and intranuclear inclusions.
Inactivated (killed or component) viral vaccines primarily generate a __(humoral/cell-mediated)__ immune response against extracellular viral antigens, preventing _______-. In contrast, live attenuated viral vaccines can generate a strong __(humoral/cell-mediated)__ immune response that can kill virally-infected cells, in addition to providing ______ immunity.
humoral viral entry into the cell cell-mediated humoral
Impaired CD40L expression can result in
hyperimmunoglobulin M syndrome (ie, high IgM levels and low/absent circulating IgG, IgA, and IgE).
The most common cause of ventricular fibrillation at age <30 is
hypertrophic cardiomyopathy
Mutations involving sarcomere proteins are responsible for
hypertrophic cardiomyopathy and certain forms of familial dilated cardiomyopathy.
Manifestations of ______ may include Chvostek sign (facial muscle contraction elicited by tapping on the facial nerve anterior to the ear) and Trousseau sign (carpopedal spasm triggered by prolonged inflation of a blood pressure cuff around the arm).
hypocalcemia
Distal RTA can cause what kind of nephrolithiasis
hypocitrituria
Most patients who have *narcolepsy with cataplexy* have undetectable levels of ________ in their cerebrospinal fluid.
hypocretin-1 (orexin-A) - Hypocretin-1 (orexin-A) and hypocretin-2 (orexin-B) are neuropeptides produced in the lateral hypothalamus that promote wakefulness and inhibit REM sleep-related phenomena. Clinical Features - Recurrent lapses into sleep or naps (≥3 times/week for 3 months) - ≥1 of the following:Cataplexy: -- Brief loss of muscle tone precipitated by strong emotion (eg, laughter, excitement) -- Low cerebrospinal fluid levels of hypocretin-1 -- Shortened REM sleep latency Associated Features: - Hypnagogic or hypnopompic hallucinations - Sleep paralysis
Howell-Jolly bodies are clusters of DNA remnants in erythrocytes due to _______ . They appear as peripheral, round, dark purple, blue, or red inclusions.
hyposplenism or asplenism (the spleen usually removes the DNA remnants) - Howell-Jolly bodies on peripheral smear reflect splenic dysfunction, which occurs in sickle cell disease due to recurrent infarction of the splenic vasculature. Functional asplenia increases the risk of invasive infection with encapsulated organisms. - Because splenic macrophages are critical in the immune response against encapsulated bacteria (eg, Streptococcus pneumoniae, Haemophilus influenzae, Neisseria meningitidis), patients with SCD are at increased risk of potentially fatal infection. Therefore, fever (with or without leukocytosis) in the setting of SCD warrants hospitalization and empiric antibiotic therapy.
The histologic findings of patchy lymphoplasmacytic infiltrates, focal fibroblastic proliferation, areas of dense fibrosis and honeycombing, and hyperplasia of type 2 pneumocytes are highly suggestive of _______
idiopathic pulmonary fibrosis (IPF) - Pirfenidone is an antifibrotic agent that inhibits TGF-β; another treatment option is nintedanib, a tyrosine kinase inhibitor that inhibits PDGF, FGF, and VEGF. Although neither drug is curative, these therapies have been shown to slow progressive fibrosis in patients with IPF.
Neuropathy of the _______ nerve presents with pain and allodynia in the anterior scrotum (labia majora in women), base of the penis (mons pubis), and medial thigh.
ilioinguinal - The nerve enters the inguinal canal anterior to the internal ring and follows the spermatic cord (round ligament in women) to the superficial ring; can be damaged/entrapped during repair of hernia - Postherniorrhaphy neuropathy refers to groin pain following hernia repair due to injury involving the cutaneous nerves of the lower abdomen/groin.
Presbyopia and skin wrinkles are age-related changes. Presbyopia occurs due to denaturation of structural proteins within the lens, leading to loss of lens elasticity which can result in _______ vision in patients with *mild myopia*. Decreased synthesis and increased breakdown of collagen and elastin contribute to the development of skin wrinkles.
improved - Presbyopia is a nonrefractive error that increases with age due to the *loss of accommodating power of the lens from decreased elasticity.* Blurry vision of nearby objects typically develops in patients age >40
What type of vaccine is the rabies vaccine?
inactivated - Postexposure prophylaxis (a medical emergency) generally includes rabies immune globulin and vaccination; it is not effective after symptom onset
Does systolic failure cause increased or decreased LV end-diastolic pressure?
increased - eventually, will increase pressure on R side as well (atrium and ventricle)
Reactive lymphocytosis is a diagnostic feature of ________
infectious mononucleosis. - lymphocytes secrete perforin
Horizontal transection of the rectus abdominis muscle must be performed with great caution as the ______ arteries enter this muscle at the level of the arcuate line.
inferior epigastric - The inferior epigastric arteries below the arcuate line are susceptible to injury (eg, hematoma) due to lack of a supporting posterior rectus sheath.
Obstruction of the _________ produces symmetric bilateral lower extremity edema, often associated with prominent development of venous collaterals in the abdominal wall.
inferior vena cava (IVC)
*Pili* are the primary virulence factor that allow Neisseria meningitidis to ...
initially attach to and colonize the nasopharyngeal epithelial surface - Pili undergo significant antigenic variation, which makes them a difficult vaccination target. - Other prominent N meningitidis virulence factors include IgA protease (destroys mucosal antibodies that would otherwise inhibit epithelial colonization), capsular polysaccharides (prevent phagocytosis and phagolysosome destruction), lipo-oligosaccharide (an endotoxin that is the major source of toxicity), and Opa-proteins (aid in endothelial attachment and invasion). - Most existing meningococcal vaccines target capsular polysaccharides. Capsular polysaccharides prevent phagocytosis and allow the pathogen to replicate and disseminate within the bloodstream. They also promote bacterial survival within phagocytes by inhibiting phagolysosome destruction.
Although GH has direct effects on target tissue (eg, chondrogenesis, myocyte protein synthesis), its growth-promoting effects are primarily mediated by ________
insulin-like growth factor-1 (IGF-1) - which is released from the liver following stimulation of hepatic GH receptors. - IGF-1 binds to a specific receptor tyrosine kinase and stimulates cell growth and proliferation in bone, cartilage, skeletal muscle, and other soft tissues.
In addition to causing lytic bone lesions, multiple myeloma causes diffuse bone loss due to _________-induced uncoupling of bone resorption and formation (ie, increased osteoclast activity without a restorative osteoblast action).
interleukin-1
Lymph from the prostate drains primarily into the ______ lymph nodes
internal iliac
The _____ artery supplies most of the structures of the pelvis, gluteal region, and medial thigh.
internal iliac
the cremaster muscle originates from the ______ muscle itself
internal oblique - The internal oblique muscle aponeurosis contributes to the formation of the conjoint tendon and rectus muscle sheath. - The conjoint tendon is the common tendon of the transversus abdominis and internal oblique muscles. It forms part of the posterior wall of the inguinal canal.
Constipation that alternates with diarrhea is characteristic of
irritable bowel syndrome
Decreased activity of hepatic N-acetyltransferase results in a diminished ability to metabolize drugs such as ______ , leading to an increased likelihood of toxicity.
isoniazid and sulfonamides
The virulence of Streptococcus pneumoniae is predominantly due to ___________ , which impedes phagocytosis and complement binding.
its polysaccharide capsule
______ mutations are responsible for the most common form of Epidermolysis bullosa
keratin - It is caused by mutations affecting proteins in the intraepidermal and dermoepidermal adhesion complexes
HIV ____ gene mutations are responsible for acquired resistance to reverse transcriptase inhibitors, protease inhibitors, and integrase strand transfer inhibitors.
pol
This patient has pure motor hemiparesis and a small cavitary lesion in the internal capsule, characteristic of a _______ .
lacunar infarct - This type of stroke affects the small penetrating arterioles - Associated with chronic HTN - In the acute setting, CT imaging may not reveal the expected hypodensity of ischemic stroke due to the small infarct size (usually <15 mm). After several weeks, these necrotic lesions turn into cavitary spaces filled with cerebrospinal fluid and surrounded by scar tissue called lacunas.
The ________ of type II pneumocytes store and release pulmonary surfactant into the fluid layer lining the inner surfaces of alveoli.
lamellar bodies - The major function of surfactant is to reduce surface tension in this fluid layer, and so a surfactant deficiency can cause alveolar atelectasis, as seen in neonatal respiratory distress syndrome.
The ASIS serves as the superior attachment of the inguinal ligament, and a penetrating injury to the region below the ASIS could damage the ________ of the thigh.
lateral cutaneous nerve
The ________ cortex is involved in executive functioning, which includes motivation, organization, planning, and purposeful action. Damage may result in dysexecutive syndrome, a syndrome characterized by significant difficulties performing these functions.
lateral prefrontal
The ______ muscles are the only muscles of mastication that aid in depressing the mandible (ie, opening the jaw). Spasm prevents spontaneous reduction of an anterior dislocation of the temporomandibular joint.
lateral pterygoid - This patient has an anterior dislocation of the temporomandibular joint (TMJ), the synovial joint that opens and closes the jaw. The joint is formed by the mandibular condyle that sits in the glenoid fossa of the squamous portion of the temporal bone. - TMJ opening involves a complex movement that has both hinge and sliding components: -- The initial movement is rotational (ie, hinge) and driven by the lateral pterygoid muscles, which are the only muscles of mastication that aid in depressing the mandible (ie, opening the jaw). -- As the jaw opens, the ligaments become taut, stopping further rotation. -- Further action by the lateral pterygoids results in translational movement (ie, condyle slides anteriorly) that opens the jaw fully. - TMJ dislocation occurs when translational movement is exaggerated due to extreme jaw opening (eg, yawning, orotracheal intubation, seizure) that causes displacement of the condyle anteriorly out of the glenoid fossa. Stretching of the ligaments causes significant pain and spasm of the muscles of mastication. This muscle spasm (specifically of the lateral pterygoids that aid jaw opening) prevents spontaneous resolution of the dislocation; manual reduction is usually necessary.
The speed of conduction down an axon depends on 2 constants: the length constant and the time constant (ie, velocity = length/time). Myelination increases the ______ constant and decreases the ______ constant, both of which *improve* axonal conduction speed.
length (aka space constant) time Demyelination thus impairs stimulus transmission. Therefore, demyelination decreases neuronal signaling velocity both by decreasing the length constant and increasing the time constant (ie, ↓ velocity = ↓ length / ↑ time) - The length constant, also known as the space constant, is a measure of how far along an axon an electrical impulse can propagate without requiring active regeneration by ion channels. It is based on the relative resistance of conduction along the axon (within the cytoplasm) compared to the resistance across the membrane. Myelin increases the length constant by reducing charge dissipation across the membrane (increasing membrane resistance). This allows the electrical impulse from individual sodium channels to travel farther, allowing activation of more distant channels. As such, demyelination will decrease the length constant and result in shorter impulse conduction. - The time constant is a measure of the time it takes for the membrane potential to respond to a change in membrane permeability (ie, sodium channel activation) and is based on membrane resistance and capacitance. Myelin decreases membrane capacitance (reduces the amount of charge stored by the membrane) and increases membrane resistance (reduces charge leakage through the membrane) in axon segments between the nodes of Ranvier; this reduces the time constant and allows the membrane potential to change faster. Demyelination would increase the time constant and result in slower changes in membrane voltage.
Produced primarily by fat cells in response to short-term food intake and long-term adequacy of fat stores, ______ acts on the hypothalamus to decrease appetite (obesity blunts this action).
leptin - During fasting states, leptin levels fall.
Patients with cleft palate are at increased risk of chronic or recurrent acute otitis media, partly because of dysfunction of the muscles (eg, _______ ) that contract against the soft palate to open the eustachian tube.
levator veli palatini
Two genetic loci are said to be in _________ when their respective alleles are inherited together in the same gamete (haplotype) more or less often than expected by chance alone given their corresponding allele frequencies.
linkage disequilibrium - Although linkage disequilibrium is often the result of physical proximity of genes on the same chromosome, it does not always imply physical linkage between the allelic loci. - In this example, the observed frequency of both alleles being inherited together is 0.2, which is greater than the expected frequency of 0.06; therefore, the population is said to be in linkage disequilibrium. This disequilibrium is explained by the close proximity of the HLA-DQA1 and HLA-DQB1 loci that code for α and β chains of class II major histocompatibility complex.
Estrogen is cleared primarily in the ___________
liver - Patients with cirrhosis commonly develop gynecomastia due to decreased clearance of estrogen along with increased production and aromatization of estrogen precursors.
Stress hyperglycemia is transiently elevated blood glucose levels in the context of severe illness (eg, sepsis, burns, major hemorrhage) in patients without preexisting diabetes mellitus. Cortisol and catecholamines released in response to severe metabolic stress act on the ______ to increase glycogenolysis and gluconeogenesis.
liver - Stress hyperglycemia is a transiently elevated blood glucose level in the context of severe illness in patients without preexisting diabetes mellitus. It is common in the intensive care unit and is typically seen in those with sepsis and other severe infections, burns, trauma, or major hemorrhage. - Severe metabolic stress is associated with increased production of cortisol, catecholamines (primarily epinephrine and norepinephrine), glucagon, and proinflammatory cytokines (eg, IL-1, IL-6, tumor necrosis factor-alpha). Cortisol, catecholamines, and glucagon act on the liver to increase glycogenolysis and gluconeogenesis, stimulating release of glucose from the liver into the blood. - In addition, the release of proinflammatory cytokines is associated with increased expression of glucose transporter (GLUT) 1 in the CNS and macrophages, along with decreased expression of GLUT4 (which mediates insulin-induced glucose uptake in peripheral tissues). This facilitates increased glucose uptake by the brain and immune cells responsible for fighting infection.
The _______ houses norepinephrine-secreting neurons that participate in activation of the "fight or flight" response to physical and emotional stressors. It is located in the dorsal pons.
locus ceruleus
Proliferative retinopathy (ie, neovascularization of the retina) is most commonly due to
longstanding, uncontrolled diabetes (a lot of other eye problems caused by DM too)
The intercostal vein, artery, and nerve lie in the subcostal groove along the ______ border of the rib and therefore provide a straightforward target for a nerve block.
lower
Clear cell carcinoma is the most common subtype of renal cell carcinoma and is composed of large, rounded, or polygonal cells with clear cytoplasm. These tumors are often detected incidentally at an advanced stage; the_______ is the most common site for metastasis, followed by osteolytic bone and liver.
lung
Silicosis is associated with increased risk of mycobacterial infections, particularly Mycobacterium tuberculosis, due to impaired _______ function.
macrophage
Patients experiencing a major depressive episode should be carefully screened for past _______ to rule out ________ .
manic episodes bipolar disorder - Antidepressant monotherapy should be avoided in patients with bipolar disorder due to the risk of precipitating mania.
In the lower extremities, the superficial lymphatic system is divided into medial and lateral tracks. The ______ track runs along the long saphenous vein up to the superficial inguinal lymph nodes, bypassing the popliteal nodes. Consequently, lesions on the ______ foot cause inguinal lymphadenopathy. In contrast, ______ lesions, which communicate with the popliteal and inguinal nodes, are more likely to cause lymphadenopathy in *both the popliteal and inguinal areas*.
medial medial lateral (lateral tract)
Is the femoral vein medial or lateral to the femoral artery?
medial (the femoral nerve is lateral) - Remember VAN --> Medial to Lateral --> Vein, Artery, Nerve
Leukocytoclastic vasculitis (Cutaneous small vessel vasculitis) is associated with ________ and typically presents with palpable purpura in the lower extremities.
medication (eg, penicillins, cephalosporins) use and infections (Hep B and C) - Drugs known to cause this condition include penicillins, cephalosporins, sulfonamides, phenytoin, and allopurinol. - On skin examination, nonblanching palpable purpura is usually present and often involves the lower extremities. - When biopsied, these skin lesions histologically demonstrate markedly inflamed small blood vessels with fibrinoid necrosis.
The RET proto-onco gene codes for what?
membrane bound Tyrosine-kinase involved in the cell-cycle - Gain of Function mutations seen in MEN 2A and B and Medullary Thyroid carcinoma (involved in MEN 2A and B too) - Loss of function: Hirschprung
In HIV, the _____ gene encodes for reverse transcriptase, integrase, and protease
pol
Osteomyelitis infection in children classically occurs in the _____ of long bones (eg, femur, tibia)
metaphyses - because this region is highly vascular yet contains *slow-flowing sinusoids* that are conducive to bacterial seeding - *Fever and refusal to bear weight are common manifestations in young children who are unable to localize the pain.* - The most common cause of osteomyelitis in children is hematogenous spread of bacteria, which may be introduced by minor (often unnoticed) trauma to a distant site.
Most common heart tumor is a __________
metastasis (eg, melanoma)
Administration of ________- will cause a decrease in cortisol synthesis via inhibition of 11-β-hydroxylase.
metyrapone - In patients with an intact hypothalamic-pituitary-adrenal axis, this will cause a reactive increase in ACTH, 11-deoxycortisol, and urinary 17-hydroxycorticosteroid levels.
What is the biochemical sign of diabetic nephropathy?
micro-albuminuria [comes after glomerular hyperfiltration] - One of the earliest derangements that contributes to the pathogenesis of diabetic nephropathy is an increase in the filtered glucose load. This increases sodium resorption in the proximal tubule by the sodium glucose cotransporter, leading to decreased sodium and fluid delivery to the macula densa and subsequent activation of the tubuloglomerular autoregulation system. Subsequent dilation of the afferent arterioles and constriction of the efferent arterioles increases intraglomerular capillary pressure, resulting in an increased glomerular filtration rate (hyperfiltration) and glomerular hypertrophy. - Although the increased filtration rate appropriately counteracts the excessive sodium reabsorption and prevents fluid retention, over a prolonged period, chronically elevated intraglomerular capillary pressures contribute to glomerular structural changes. These include basement membrane thickening, mesangial expansion, and broadening of the podocyte foot processes, which result in the loss of small amounts of albumin in the urine (30-300 mg/day, or moderately increased albuminuria). Albuminuria is the earliest clinical sign of diabetic nephropathy and typically occurs before any appreciable rise in serum creatinine. Later in the disease process, there is widespread glomerulosclerosis and a decline in glomerular filtration.
In ____________ disease, loss of negative charge leads to selective loss of albumin in the urine
minimal change disease
Sepsis is a host inflammatory response to infection that can lead to multiple organ dysfunction due to defective ________ , resulting in a widespread dissociation between oxygen delivery and extraction.
mitochondrial oxidative respiration - This manifests as elevated central venous oxygen saturation (elevated O2 in Superior Vena Cava) Septic organ dysfunction is driven mainly by poor tissue oxygen use. This cellular dysoxia is caused by 3 major mechanisms: - Bacterial components (eg, endotoxin) and acute phase cytokines (eg, IL-1-beta) trigger production of free radicals that damage mitochondria and interfere with the electron transport chain. Immediate postmortem analysis of patients with sepsis reveals surprisingly minimal tissue necrosis but, often, extensive mitochondrial damage. This mitochondrial dysfunction leads to decreased oxidative phosphorylation with loss of ATP production. A compensatory bioenergetic shift toward glycolysis often results in lactic acidosis. - Widespread microcirculatory failure with vasodilation causes blood to shunt rapidly through organs, decreasing the opportunity for oxygen extraction. - Increased capillary permeability causes tissue edema (third spacing), which increases the diffusion distance for oxygen to reach mitochondria of target cells.
The anterior two-thirds of the posterior limb of the internal capsule is mainly composed of _____ fibers (eg, corticospinal tract), and the posterior one-third contains ____ fibers (eg, thalamocortical tract).
motor sensory - Although very small lesions to the posterior limb may cause contralateral pure sensory deficits, most lesions result in pure motor or combined sensorimotor deficits.
Treatment of localized impetigo is with topical antibiotics (eg, _____ )
mupirocin - If impetigo is caused by Group A strep (usually caused by Staph aureus), a minority of patients may develop poststreptococcal glomerulonephritis (PSGN) several weeks after impetigo caused by GAS (as indicated by this patient's Gram stain showing gram-positive cocci in chains). - Renal damage is caused by immune complex deposition as well as complement activation, leading to a massive inflammatory response that damages the glomerular basement membrane. - Symptoms of PSGN range from asymptomatic, microscopic hematuria to gross hematuria and nephrotic-range proteinuria. In addition to tea- or cola-colored urine, patients may develop periorbital/facial swelling, generalized edema, and hypertension. - Laboratory evaluation typically reveals elevated creatinine and decreased complement C3 level.
Activation of ______ receptors by acetylcholine or cholinergic agonists results in peripheral vasodilation due to synthesis of nitric oxide in endothelial cells, which leads to vascular smooth muscle relaxation (eg, hypotension). ______ receptor activation in other sites causes smooth muscle _______ .
muscarinic Muscarinic contraction - In contrast, activation of M3 receptors in other sites leads to a G-protein-coupled increase in intracellular calcium, resulting in smooth muscle contraction. Clinically, this contraction manifests as detrusor bladder muscle contraction, pupillary constriction or miosis, and exocrine gland secretion (eg, salivation) - M2 receptors are predominantly found in cardiac muscle. Activation of M2 receptors leads to a G-protein-coupled decrease in intracellular cyclic-AMP and opens potassium channels to slow depolarization. This combination results in decreased inotropy (less contractility) and chronotropy (decreased heart rate).
The green discoloration of pus or sputum seen during common bacterial infections is due to the presence of _______
myeloperoxidase - a blue-green heme-based enzyme that is released from neutrophil azurophilic granules and forms hypochlorous acid (bleach).
The contractile mechanism in skeletal muscle depends on proteins ( _____ ) as well as calcium ions.
myosin II, actin, tropomyosin, and troponin
Cancer immunotherapy often includes the administration of monoclonal antibodies against a target overexpressed on the cancer cell surface. The Fc portion of the bound antibody is identified by _______ , leading to antibody-dependent cellular cytotoxicity via the release of *granzymes and perforin*
natural killer cells via CD16
Is E. coli oxidase positive or negative?
negative - it does ferment lactose tho
Embryonic origin of neuroblastoma + Genetic component
neural crest cells of adrenal medulla N-myc gene amplification
Abscess formation (ex: air abscess in lung) is largely driven by _______ recruitment and activation leading to the release of cytotoxic granules that kill bacteria but also cause liquefying necrosis of surrounding tissue.
neutrophil
Neurocysticercosis is common in developing regions and usually presents years after infection with
new-onset seizure - Physical examination, laboratory evaluation, and cerebrospinal fluid analysis are generally normal. - However, brain imaging typically shows ≥1 cysts [calcifications; not ring-enhancing lesions] in various stages of viability.
Pulmonary function testing in cystic fibrosis reveals an __(obstructive/restrictive)__ pattern
obstructive - Decreased: FEV1/FVC ratio - Increased: total lung capacity and residual volume.
The ______ artery is a branch of the internal iliac artery that runs inferiorly to supply blood to the bladder and medial compartment of the thigh
obturator artery
Petroleum processing can result in exposure to sulfur oxides and aromatic hydrocarbons; these can cause ________
occupational asthma and (rarely) bronchiolitis obliterans --> which result in air trapping and bronchial wall thickening - as opposed to the pleural thickening seen in asbestos exposure
Primary amebic encephalitis occurs when the free-living, motile protozoan *Naegleria fowleri* penetrates the _______ mucosa and migrates in a retrograde fashion through the _______ to the brain. This rare, deadly infection primarily occurs after exposure to *warm, fresh water* during recreational activities.
olfactory olfactory nerve
Patients with ______ cortex injury often experience personality changes, disinhibition, and irritability secondary to impairment of the behavioral and emotional modulatory systems.
orbitofrontal
Impaired bone remodeling leads to _______
osteopetrosis - Mutation in carbonic anhydride II prevents the proper acidification needed to initiate bone resorption
Turner syndrome (45, XO) and Klinefelter syndrome (47, XXY) increase the risk of ______ tumors and ______ tumors, *respectively*
ovarian germ cell extragonadal germ cell
Crohn disease is associated with ________ kidney stones
oxalate - In the healthy bowel, dietary calcium binds to dietary oxalate, producing insoluble calcium oxalate salts that are eliminated in the feces. But in malabsorptive syndromes such as Crohn disease, calcium forms soap complexes with the excess fat in the intestinal lumen and is unavailable for complexing with oxalate. As a result, free oxalate absorption is increased and subsequently filtered into the urine, promoting the formation of oxalate kidney stones (enteric oxaluria).
Where is proinsulin cleaved into insulin + c peptide?
pancreatic beta *secretory cells* - via the enzyme endopeptidase - stored here in granules until secreted (in equimolar amounts)
Bleeding into the _______ is frequently due to trauma (eg, pelvic fracture) or gynecologic hemorrhage (eg, ruptured ectopic pregnancy).
pelvic cavity
The ______ nerves provide *parasympathetic* innervation to the bowel and bladder, and their impairment in cauda equina syndrome can cause constipation and difficulty urinating.
pelvic splanchnic nerves (S2-S4) - Other signs of cauda equina syndrome include radicular low back pain and leg weakness (sciatic nerve) as well as saddle anesthesia (pudendal, ilioinguinal nerves).
Porin mutations can confer ________ resistance and are particularly important in gram-negative organisms such as Pseudomonas.
penicillin and aminoglycoside
What is the most specific physical exam finding for myocarditis/pericarditis?
pericardial friction rub
Elevated cholesterol concentrations increase the likelihood of cholesterol precipitation and gallstone formation. High levels of bile salts and _________ increase cholesterol solubility and decrease the risk of gallstones.
phosphatidylcholine - Removal of excess cholesterol from the body occurs via 2 mechanisms: excretion of free cholesterol into bile and conversion of cholesterol into bile acids. In the *liver*, free cholesterol is converted into *cholic and chenodeoxycholic acids* through a series of chemical reactions beginning with *cholesterol 7α-hydroxylase (rate-limiting step in bile acid synthesis)*. These bile acids are then conjugated to either *glycine or taurine (improving solubility and emulsifying ability)* to create the bile salts that are actively secreted into the bile canaliculi. As *water-insoluble cholesterol* is secreted in bile, it is rendered soluble in small amounts by the detergent action of these amphipathic (eg, hydrophobic and hydrophilic) *bile salts and phosphatidylcholine (a phospholipid)*. When there is more cholesterol than can be made soluble, it *precipitates into crystals* that eventually grow and merge to form *gallstones*. - Gallbladder hypomotility further promotes cholesterol nucleation and gallstone formation.
The ________- is the primary source of ATP at the beginning (eg, first 10 sec) of exercise.
phosphocreatine shuttle - Phosphocreatine supplies a brief burst of energy before being quickly depleted. - Increased dietary intake of creatine can enhance this phase of ATP production by increasing sarcoplasmic phosphocreatine stores.
The *right* _______ courses along the pericardium overlying the right side of the heart and is at risk for injury during procedures in or near the right atrium (eg, radiofrequency ablation).
phrenic nerve - Right phrenic nerve injury is typically recognized by elevation of the right hemidiaphragm.
Extended-spectrum beta-lactamases (ESBL) can be produced by gram-negative bacteria, rendering cephalosporins and other beta-lactam antibiotics inactive. These genes can be transmitted between organisms through __________ .
plasmid conjugation - Carbapenems (eg, imipenem) are the treatment of choice for ESBL-producing organisms (although unfortunately, organisms with carbapenem resistance have emerged). - Cilastatin must be given with imipenem only due to its nephrotoxicity
Sometimes, one gene mutation leads to multiple, seemingly unrelated phenotypic abnormalities, a genetic phenomenon termed ________ .
pleiotropy
Once malignant cells have metastasized to the pleural space, they can occlude the _______ located on the parietal surface and prevent pleural fluid reabsorption.
pleural lymphatic stoma - This is likely the primary mechanism of malignant pleural effusion in this patient with evidence of pleural metastasis (ie, atypical mucin cells in pleural fluid).
Group B Streptococcus is a common cause of neonatal meningitis. Its major virulence factor is a ________ , which dramatically reduces the effectiveness of host defense mechanisms due to molecular mimicry.
polysaccharide capsule (with abundant sialic acid [inhibits C3b and C5a (anaphylatoxin)]) - gram positive cocci in short chains
The _______ respiratory centers coordinate normal respiratory drive. Immaturity of these *central* respiratory centers causes apnea of prematurity, which is common in *extremely preterm newborns*.
pontine and medullary
blood supply to midbrain
posterior cerebral artery (PCA)
Excess Radioactive iodine can be taken up by the thyroid gland and cause hypothyroidism, tissue damage, and thyroid carcinoma. In the event of a nuclear accident, _________ is given prophylactically to protect the thyroid from excessive accumulation of radioactive Iodine.
potassium iodide - it competitively inhibits the radioactive iodines uptake into cells
Infections caused by Schistosoma (schistosomiasis), Clonorchis sinensis (clonorchiasis), and Paragonimus westermani (paragonimiasis) are treated with
praziquantel.
Cholangiocarcinoma is associated with ______
primary sclerosing cholangitis
- Dyspnea, - uneven chest expansion. - Chest pain, - decreased tactile fremitus - hyperresonance, - diminished breath sounds - ALL ON THE EFFECTED SIDE Due to rupture of subpleural bleb or cyst
primary spontaneous pneumothorax - occurs most frequently in tall, thin young male
Non-selective beta blockers
propranolol, timolol, nadolol
Frothy, foamy urine may be caused by ________ in the urine
proteinuria or bile salts
Clear cell carcinoma is the most common type of renal cell carcinoma and originates from the epithelial cells of the ______
proximal renal tubules - Gross pathology typically demonstrates a sphere-like mass composed of golden-yellow cells (due to high lipid content) with areas of necrosis and hemorrhage.
IL-12 and IL-23 are produced by activated T cells and play a prominent role in the pathogenesis of _______
psoriasis
Immediately after birth, decreased ________ vascular resistance (due to oxygenation and ventilation of the lungs) and increased _______ vascular resistance (due to removal of the placenta from circulation) reverse the flow across the ductus arteriosus to left-to-right.
pulmonary systemic
Elevated ________ is the cause of pleural effusion in decompensated heart failure. Reduced ________ contributes to pleural effusion in conditions that cause hypoalbuminemia (eg, malnutrition, nephrotic syndrome).
pulmonary capillary hydrostatic pressure pleural capillary oncotic pressure - The pleural fluid/serum lactate dehydrogenase ratio is *<0.6* with transudative effusions.
Serotonin-releasing neurons in the central nervous system (CNS) are located in the ______ .
raphe nuclei
Hyperthyroidism causes upregulation of beta-adrenergic receptor expression, leading to increased catecholamine effect. Beta blockers are used to blunt the adrenergic manifestations of hyperthyroidism. In addition, lipid-soluble beta blockers ...
reduce conversion of T4 to T3 by inhibiting 5'-monodeiodinase in peripheral tissues.
Is staph saprophyticus novobiocin sensitive or resistant? Is it coagulase positive or negative?
resistant negative - staph epidermidis is sensitive to novobiocin and also coagulase negative - does not cause hemolysis
Obesity, particularly morbid, central obesity, can cause a pattern of extrinsic _______ pulmonary function tests.
restrictive - Decreased: FEV1, FVC, ERV, FRC, TLC - Normal: RV (abdominal obesity causes greater impairment)
Daptomycin can cause what AE
rhabdomyolysis --> elevated creatinine phosphokinase (like HIV integrase inhibitors) - MOA: disrupts the bacterial membrane by creating transmembrane channels that cause intracellular ion leakage and cellular membrane depolarization
The coronary sinus communicates freely with the right atrium and will become dilated secondary to any factor that causes increased ________
right atrial pressure. - The most common cause is pulmonary hypertension, leading to elevated right heart pressures. - The CS runs transversely in the left atrioventricular groove on the posterior aspect of the heart, and opens into the right atrium between the inferior vena cava and tricuspid valve at the CS orifice. Because the CS communicates freely with the right atrium, it will become dilated by any factor that causes dilation of the right atrium. - The most common cause of coronary sinus dilation evident on echocardiography is elevated right-sided heart pressure secondary to pulmonary hypertension. CS dilation also occurs in patients with anomalous venous drainage into the CS, including persistent left superior vena cava and total anomalous pulmonary venous return. - The presence of asymptomatic coronary artery disease usually does not change the size of the CS. Long-standing left ventricular systolic dysfunction due to prior myocardial infarction and ischemic cardiomyopathy can lead to secondary pulmonary hypertension, with the possibility of CS dilation over time.
The sinoatrial node consists of specialized pacemaker cells located at the junction of the _________ . It is the site of earliest electrical activation in patients with sinus rhythm.
right atrium and superior vena cava
Increased R atrial pressure with normal or decreased LV end-diastolic pressure suggests...
right-sided heart failure in the absence of left-sided heart failure - as can occur with pulmonary arterial hypertension or hypoxic lung disease (eg, interstitial lung disease).
Cyanotic congenital heart disease, characterized by _________ , should be considered in neonates with severe cyanosis that does not improve with oxygen administration.
right-to-left shunting - In transposition of the great arteries (abnormal origination of the aorta from the right ventricle and the pulmonary artery from the left ventricle), deoxygenated blood from the right ventricle is delivered to the systemic circulation while oxygenated blood cycles through the pulmonary circulation. --> The abnormal position of the aorta directly on top of the pulmonary artery results in a *narrow-appearing mediastinum*.
Characteristic features of congenital ___________ include hearing loss, cataracts (cloudy cornea), and cardiac defects (eg, patent ductus arteriosus)
rubella
Congenital cataract can be seen with in-utero _____ infection.
rubella - CMV-related complications observed in infants exposed to the virus in utero include chorioretinitis (most common eye-related problem), sensorineural deafness, seizures, jaundice, hepatomegaly, splenomegaly, and microcephaly. - Enveloped , (+ve) ssRNA, icosahedral nucleocapsid - Contrast: Measles (rubeola) is (-ve) ssRNA
The Papanicolaou test is used to
screen cervical cytology specimens for dysplasia caused by oncogenic strains of human papillomavirus.
Rapid onset of numerous _______ (pigmented macules or plaques with a greasy surface and well-demarcated borders) is a classic indicator of internal malignancy (Leser-Trélat sign), particularly *gastric adenocarcinoma*
seborrheic keratoses - It is thought to occur in response to increased tumor production of cytokines or growth factors (eg, IGF-1, fibroblast growth factor).
Somatostatin secreted from pancreatic "delta cells" decreases the secretion of
secretin cholecystokinin glucagon insulin gastrin. - Somatostatinomas are rare pancreatic islet cell tumors that arise from delta cells. - Patients with somatostatinomas present with hyperglycemia or hypoglycemia, steatorrhea (excessive fat in the feces), and gallbladder stones. - Gallbladder stones form because of poor gallbladder contractility, which is secondary to inhibition of *cholecystokinin* release.
Pregnant women with severe preeclampsia can develop HELLP (Hemolysis, Elevated Liver enzymes, Low Platelet count) syndrome. Nausea/vomiting and right upper quadrant pain occur due to liver ischemia and/or hemorrhage (eg, subcapsular hematoma). These patients are also at risk for ______ , *renal insufficiency, and disseminated intravascular coagulation* due to widespread endothelial dysfunction.
seizure - Bleeding esophageal varices typically occur in patients with liver cirrhosis due to venous portal hypertension. In contrast, HELLP syndrome and preeclampsia cause arterial hypertension.
MOA of Esmolol
selective beta-1 receptor blocker, decreases left ventricular contraction velocity and heart rate to reduce blood pressure per time
Is staph epidermidis novobiocin sensitive or resistant? Is it coagulase positive or negative?
sensitive - staph saprophyticus is resistant, and also coagulase negative - does not cause hemolysis
Is Staph epidermidis sensitive or resistant to novobiocin
sensitive (contrast with staph saprophiticus)
Alpha-1 antitrypsin (AAT) is a _______ protease inhibitor that regulates the activity of elastase in the lung.
serine - Histologically, AAT deficiency can demonstrate reddish-pink globules on periodic acid-Schiff stain; these globules represent unsecreted, polymerized AAT in the periportal hepatocytes.
Tumor necrosis factor alpha (TNF-α) is a proinflammatory cytokine that induces insulin resistance through the activation of _________
serine kinases ... which then phosphorylate serine residues on the beta subunits of IR and IRS-1. - This inhibits tyrosine phosphorylation of IRS-1 by IR and subsequently hinders downstream signaling, resulting in resistance to the normal actions of insulin. - Phosphorylation of *threonine residues has similar effects* - Catecholamines, glucocorticoids, and glucagon can also induce insulin resistance by this same mechanism.
A chest tube for drainage of pleural effusion is placed through the skin and subcutaneous fat into the 4th or 5th intercostal space in the anterior axillary or midaxillary line. The tube traverses through the _______ muscle, intercostal muscles, and parietal pleura.
serratus anterior
Exertional dyspnea, pneumonia resulting in life-threatening acute chest syndrome, and recurrent abdominal and bone pain are clinical features of _______ .
sickle cell anemia
Pappenheimer bodies are aggregated iron deposits in erythrocytes that are often seen in patients with ______ . They appear as dark blue inclusions.
sideroblastic anemia
Children with watery diarrhea should be treated with oral rehydration solutions containing hypotonic, equimolar concentrations of _______ to help prevent dehydration and electrolyte abnormalities.
sodium and glucose
The ventral posterior lateral nucleus (receives input from the _______ and the _____ ) and ventral posterior medial nucleus (receives input from the _____ ) of the thalamus send somatosensory projections to the cortex via thalamocortical fibers.
spinothalamic tract and dorsal columns trigeminal pathway - Damage to these nuclei (eg, due to ischemia, hemorrhage) may result in complete contralateral sensory loss (eg, touch, pain/temperature, vibration/proprioception). Severe proprioceptive defects may cause unsteady gait.
Coxsackie virus genome
ssRNA (+)ve sense
West Nile Virus genome + Mode of Transmission
ssRNA (+)ve sense Culex spp (female mosquito) - most commonly in the summer in warmer regions [Southern US, Latin America, Africa]
Ghrelin is produced in the ______ in response to fasting
stomach - *Ghrelin stimulates appetite and promotes weight gain. Leptin and insulin act in the CNS to decrease appetite*. - *Caloric restriction leads to increased ghrelin levels along with decreased insulin and leptin levels, causing an increase in appetite that can make it difficult to maintain weight loss.* - levels surge leading up to meals and fall after eating. Ghrelin stimulates appetite and promotes weight gain. Patients who have undergone gastrectomy have reduced ghrelin levels, leading to weight loss.
Which strep is bile soluble and optochin sensitive?
strep pneumniae (group B; alpha hemolytic)
Eccentric hypertrophy in Aortic regurg eventually leads to increased ________ to help maintain cardiac output
stroke volume
rupture of bridging veins
subdural hematoma (crescent shaped)
In Hirschsprung Disease, the ________ of the narrowed area is the most superficial layer where the absence of ganglion cells can be confirmed during biopsy procedures.
submucosa
The third part of the duodenum courses horizontally across the abdominal aorta and inferior vena cava at the level of the third lumbar vertebra. The _______ lie *anterior* to the duodenum at this location.
superior mesenteric vessels
The common cardinal veins of the developing embryo drain directly into the sinus venosus. These cardinal veins ultimately give rise to the _______ and other constituents of the systemic venous circulation.
superior vena cava
Extrinsic compression of the superior vena cava by a mediastinal mass (eg, malignancy) can cause _____ , with impaired venous return from the upper body. Signs and symptoms include *facial swelling, distended collateral veins, headache, and dyspnea*.
superior vena cava syndrome
Enlargement of the ________ lymph nodes, which drain the chest and abdomen, is unlikely to be caused by common childhood infections and is concerning for malignancy.
supraclavicular
Mutations to viral ______ can alter tissue tropism and cause noninfective viruses to become infectious.
surface glycoproteins - The tissue tropism of viruses is primarily mediated by viral surface glycoproteins that bind to specific host cell receptors.
This patient most likely has appendicitis, which is usually treated by removing the appendix. During the procedure, the ______ can be used as a surgical landmark.
teniae coli
The _____ ligament of the ovary (ie, infundibulopelvic ligament) contains the ovarian artery, ovarian vein, lymphatics, and nerves. The ovarian artery is the major blood supply to the ovary. Therefore, this ligament must be ligated during an oophorectomy to prevent heavy bleeding.
suspensory
Translocation for Ewings sarcoma?
t(11;22) [FLI1 and EWSR1]
Resistance to ___________ is due at least in part to a decrease in the levels of drug accumulation due to decreased uptake and/or increased efflux.
tetracycline and sulfonamides
Head and neck squamous cell carcinomas typically spread first to
the anterior cervical lymph nodes via the lymphatics. - The involvement of anterior cervical lymph nodes affects the staging of the disease.
Duodenal ulcer results from H pylori colonizing _______
the gastric antrum - Can also result from NSAID use - Chronic inflammation due to H pylori colonization in the gastric antrum leads to depletion of somatostatin-producing cells (delta cells), which are located mostly in the antrum. - Somatostatin inhibits gastrin release from G-cells. In its absence, elevated gastrin levels act directly (via cholecystokinin B receptors) and indirectly (via histamine release by enterochromaffin-like cells) to increase acid secretion by parietal cells. - In addition, H pylori releases cytotoxins that inhibit duodenal production of bicarbonate. The resultant increased acid load is emptied into the under-protected duodenum, leading to duodenal ulcer formation.
Gastric ulcer results from H pylori colonizing ________
the gastric body (corpus) - Chronic inflammation leads to multifocal atrophic gastritis and a reduction in the number of acid-producing parietal cells, which are located mostly in the gastric body. - Delta cells in the antrum are not markedly reduced, therefore acid secretion is often low to normal. Gastric ulcer formation results from direct mucosal damage caused by bacterial products (eg, ammonia, cytotoxins) and the resultant inflammatory response.
Neonatal hypoglycemia is common in infants of diabetic mothers. The pathophysiology involves maternal hyperglycemia, which in turn causes fetal hyperglycemia and compensatory hyperfunctioning of ________ .
the pancreas (ie, hyperinsulinemia) - After birth, persistently elevated insulin levels lead to transient hypoglycemia.
PDA is an abnormal connection between
the pulmonary artery and the aorta [usually closes shortly after birth due to increasing SVR]
Clearance of particles that lodge distal to __________ is dependent on phagocytosis by alveolar macrophages.
the terminal bronchioles - The terminal bronchioles are covered by ciliated cuboidal epithelium and club cells, which help with mucociliary clearance in this region. - Submucosal mucous and mucoserous glands help form the mucous layer in the larger airways. They are found within the trachea and bronchi but not in the bronchioles.
Acoustic neuromas are Schwann cell-derived tumors that typically arise from _______ and are commonly located at the cerebellopontine angle (between the cerebellum and lateral pons). Patients usually present with unilateral sensorineural hearing loss and tinnitus.
the vestibular portion of the vestibulocochlear nerve (CN8) - This patient's clinical presentation is suggestive of acoustic neuroma, a Schwann cell-derived tumor that typically arises from the vestibular portion of the vestibulocochlear nerve (CN VIII). The vestibulocochlear nerve exits the brainstem from the pontomedullary junction, lateral to the facial nerve, and enters the cerebellopontine angle (between the cerebellum and lateral pons). Patients with acoustic neuroma usually have ipsilateral sensorineural hearing loss and tinnitus (ear ringing/buzzing) due to impairment of the cochlear portion of the nerve. Damage to the vestibular component may also result in vertigo, dysequilibrium, and nystagmus. Most cases present unilaterally, but bilateral acoustic neuromas are frequently seen in patients with neurofibromatosis type 2.
Non-selective beta blockers are contraindicated in which patients
those with COPD or asthma because they can trigger bronchospasm due to beta-2 blockade
Median nerve injury at the level of the carpal tunnel may result in weakness of
thumb abduction, flexion, and opposition. - Median nerve injury at the level of the carpal tunnel may result in both sensory and motor deficits in the distribution of the median nerve's distal branches: - Palmar digital branches: numbness, pain, and/or paresthesia in the palmar surface of the first 3½ digits; weakness of the first and second lumbrical muscles (interphalangeal joint extension) - Recurrent branch of the median nerve to the thenar muscles: weakness of the abductor pollicis brevis (thumb abduction), flexor pollicis brevis (thumb flexion), and opponens pollicis (thumb opposition)
In B pertussis, _________ directly damages and *destroys ciliated epithelial cells*, leading to a loss of airway protection, subsequent microaspiration, and development of the characteristic paroxysmal cough.
tracheal cytotoxin
FEV1, FVC, and TLC may be increased in
trained athletes
In _______ , a bacteriophage (virus) transfers DNA from one bacterial cell to another.
transduction - By this mechanism, bacteria can acquire genes for virulence and antibiotic resistance.
Hyperthyroidism causes increased bone turnover with net bone loss, potentially leading to osteoporosis. The bone loss is driven by ________ , which _______ , increased bone resorption, and release of calcium.
triiodothyronine (T3) stimulates osteoclast differentiation
Besides the cervix and anus, HPV can infect what structure of the body?
true vocal cords
Acute lesions to the cerebellar vermis typically cause *add other cerebellar lesions to notecards
truncal and gait ataxia [due to impaired modulation of the medial-descending motor systems.] - Involvement of the lower vermis and the flocculonodular lobe also causes vertigo/nystagmus due to dysregulation of the vestibular nuclear complex.
Failure of conotruncal septation results in persistent ______ , which can present with cyanosis and respiratory distress, although an echocardiogram will show a single arterial trunk overriding a large VSD
truncus arteriosus
Neisseria gonorrhoeae and Chlamydia trachomatis can cause acute cervicitis (eg, purulent cervical discharge, friable cervix). Untreated, cervicitis can progress to pelvic inflammatory disease and long-term complications such as _______ and ________
tubal factor infertility and ectopic pregnancy - Acute cervicitis classically presents with purulent cervical discharge and a friable cervix that bleeds easily with contact (ie, postcoital bleeding). - Microscopy showing inflammation (eg, neutrophils) without a visible pathogen is classic for cervicitis due to Chlamydia trachomatis or Neisseria gonorrhoeae, which are often identified by nucleic acid amplification testing. - If left untreated, cervicitis can compromise the endocervical barrier, allowing polymicrobial vaginal flora to ascend into the normally sterile uterus and fallopian tubes. In contrast to cervicitis, infection involving the upper genital tract (ie, pelvic inflammatory disease [PID]) can cause fever, abdominal pain, and cervical motion/uterine/adnexal tenderness due to increased bacterial load and spread. - When the infection extends to the fallopian tube, it creates an inflammatory exudate (ie, salpingitis) that causes the tubal walls to adhere. With prolonged infection, the exudate may be replaced by scar tissue, causing permanent tubal scarring and obstruction that impedes the fertilization and/or implantation of future pregnancies. Therefore, common complications of PID include tubal factor infertility and ectopic pregnancy.
Urinary tract obstruction causes reflux of urine into the renal tubules and increased _______ pressure.
tubular hydrostatic - This patient has a kidney stone in the left ureter; the hydroureter and hydronephrosis suggest acute urinary tract obstruction. The resultant reflux of urine backward into the relatively noncompliant renal tubules results in increased renal tubular hydrostatic pressure - The intraglomerular capillary hydrostatic pressure is unchanged, resulting in a decreased hydrostatic pressure gradient across the glomerular capillary wall and a *reduction in glomerular filtration*. - Oncotic pressure is maintained by large plasma proteins which are not filtered across the glomerular capillary basement membrane; it is unaffected by a urinary tract obstruction.
In cancer-related cachexia, high levels of pro-inflammatory cytokines lead to increased _________ , which in turn leads to extensive skeletal muscle loss.
ubiquitination of sarcomeric muscle proteins - The ubiquitin-proteasome pathway mediates targeted protein degradation, which allows for rapid disposal of unneeded intracellular proteins.
The subclavian vein is the continuation of the axillary vein. Both drain blood from the upper extremity. Blockage at any of these 2 sites would cause
unilateral arm swelling without associated facial swelling
The _____ can be injured during pelvic surgery due to its proximity to major pelvic ligaments and vessels such as the uterine artery within the cardinal ligament.
ureter - Unintentional suturing of the ureter can present postoperatively with unilateral back pain (ie, hydronephrosis) due to ureteral obstruction.
Flank pain radiating to the groin with a ballotable (ie, palpatable between both hands) flank mass that develops within a week of pelvic surgery suggests ___________
ureteric obstruction --> hydronephrosis - The ureter runs in close proximity to the pelvic vessels. It courses anterior to the iliac vessels (area of resection of the pelvic nodes, which drain the uterus and cervix) and just posterior to the uterine artery near the lateral fornix of the vagina. - It is vulnerable to injury during pelvic surgery, such as that involved in hysterectomy with pelvic lymphadenectomy. - Unintentional ureteral ligation causes obstruction with hydronephrosis and flank pain due to distension of the ureter and renal pelvis. Urine output and serum creatinine remain within normal limits in most individuals with unilateral obstruction because the contralateral kidney functions normally and compensates for decreased functioning of the affected kidney.
Benign prostatic hyperplasia can increase resistance to urine flow in the urethra and lead to incomplete bladder emptying during micturition. The residual urine can act as a growth medium for pathogenic bacteria and increase the risk for ____________ .
urinary tract infection
The ______ nerve stimulates gastric parietal cell production of hydrochloric acid; injury may therefore lead to decreased gastric acid secretion (ie, hypochlorhydria), not increased secretion.
vagus
Pregnant women > 20 weeks gestation can experience compression of the inferior cava by the gravid uterus while in the supine position. This reduces ________, which can result in hypotension and syncope.
venous return and cardiac output
Branches of the _______ pass through the esophageal hiatus. Damage to these branches, which can occur during esophageal hiatal hernia repair (eg, fundoplication), may result in *delayed gastric emptying and gastric hypochlorhydria*
vagus nerve (ie, anterior and posterior vagal trunks) - the anterior and posterior vagal trunks (branches of the vagus nerve) also pass through the esophageal hiatus and are vulnerable to injury during fundoplication. These nerves supply parasympathetic innervation to the gastrointestinal tract and stimulate gastric muscle contraction and motility. Injury to the vagal trunks can lead to delayed gastric emptying (ie, gastroparesis), manifesting with abdominal pain, early satiety, and postprandial emesis.
In homozygous sickle cell disease (sickle cell anemia), there are point mutations in both beta globulin genes that substitute _____ for _____ at position 6
valine --> glutamine - patients will have HbS, HbF, and HbA2 (not HbA) - hydroxyurea, which increases HbF production, is often administered to limit symptoms and complications of the disease. Contrast: Patients with hemoglobin SC disease (not referring to sickle cell disease or sickle cell trait) - have 1 beta globulin with the sickle mutation and 1 beta globulin with a mutation that *substitutes lysine for glutamine at position 6.* - They produce two predominant hemoglobins: HbS and Hemoglobin C, the latter of which is not seen in sickle cell anemia as there is no hemoglobin C mutation.
Mononuclear interstitial pulmonary infiltrates are found in _________
various interstitial lung diseases (eg, idiopathic pulmonary fibrosis).
Endothelin-1 (ET-1) is a potent endogenous ___(vasodilator/vasoconstrictor)___ , mainly secreted by endothelial cells.
vasoconstrictor Endothelin Receptor antagonists: - Competitively antagonizes endothelin-1 receptors --> decreased pulmonary vascular resistance. - Hepatotoxic (monitor LFTs). - Example: bosentan.
Septic shock is a dysfunctional host response to an infectious pathogen resulting from massive *upregulation of vasodilators*. A ________ deficit contributes to unbalanced vasodilation and refractory hypotension.
vasopressin - In septic shock, vasopressin is suppressed, possibly due to impaired baroreceptor reflexes and/or depletion of endogenous stores. - Sepsis is a florid host inflammatory response to an infectious pathogen that can lead to widespread dysfunction of multiple organ systems. Cardiovascular manifestations include profound vasodilation resulting in low systemic vascular resistance and hypotension. Refractory hypotension (ie, vasoplegia) despite adequate intravascular volume (ie, normal jugular venous pressure), as in this patient, indicates progression to septic shock. - Septic shock is an extreme manifestation of sepsis, in which vasodilatory mediators overwhelm endogenous vasoconstrictor mechanisms. Key vasodilators include nitric oxide and prostaglandins; their production is upregulated by acute-phase cytokines such as tumor necrosis factor-α, IL-1, and IL-6 released from innate immune cells and endothelium exposed to bacterial cell wall glycoproteins and endotoxins
Decreased coronary blood supply due to vasospasm is seen in patients with
vasospastic (Prinzmetal) angina - Coronary vasospasm typically affects relatively young patients (age <50)
Ischemic injury to the bilateral _______ can lead to locked-in syndrome, a condition in which patients are unable to move or speak (due to interruption of the corticospinal and corticobulbar tracts) but retain consciousness, sensation, eye opening, and vertical eye movements.
ventral pons
How does rabies get to the brain?
via the brainstem Rabies migrates centrally through peripheral nerves to the spinal cord and then rapidly ascends to the brain. Patients with rabies usually have preceding history of animal bite; furthermore, rabies is a virus, not an amoeba, and it generally presents with several days of constitutional symptoms followed by fever, hydrophobia, and pharyngeal spasm.
Malabsorption caused by celiac disease can lead to _______ deficiency. Patients have what lab values?
vitamin D --> can present as rickets or osteomalacia (depending on age) - Normal functions of vit D: increase intestinal absorption of Ca and PO; inhibit release of PTH Lab values: - decreased serum phosphorus - increased serum parathyroid hormone (secondary hyperparathyroidism) - low (or normal) serum calcium. - increased alkaline phosphatase due to increased bone turnover
Patients with ________ often present with a lifelong history of mucosal bleeding, including gingival bleeding, epistaxis, and/or menorrhagia. These patients have normal platelet levels but typically have a prolonged bleeding time due to impaired platelet functioning.
von Willebrand disease
Failure of aggregation with ristocetin assay occurs in
von Willebrand disease Bernard-Soulier syndrome. - Ristocetin activates vWF to bind GpIb. - Following endothelial damage, von Willebrand factor (vWF) binds glycoprotein Ib receptors on platelets to mediate platelet adherence. The ristocetin cofactor assay measures platelet agglutination via binding of glycoprotein Ib receptors to vWF; it will be abnormal in vWF deficiency but will correct with the addition of normal (vWF-containing) plasma.
In _________ , DNA is hypersensitive to UV radiation, causing premature skin aging and increased risk of skin cancer (malignant melanoma and squamous cell carcinoma).
xeroderma pigmentosum
The syncytiotrophoblast is the outer layer of chorionic villi that synthesizes and secretes hormones, such as hCG. What is the function of hcg in pregnancy?
β-hCG [structurally similar to LH] is a hormone secreted by the placental syncytiotrophoblast after uterine invasion --> signals the ovary to maintain the corpus luteum, which produces progesterone in early pregnancy.
A moderately elevated alkaline phosphatase of unclear etiology should be followed up with __________
γ-glutamyl transpeptidase (GGTP) - Bone and liver are the primary sources of alkaline phosphatase - GGTP is not present to a significant extent in bone. It is therefore particularly useful in determining whether an elevated alkaline phosphatase is of hepatic or bony origin
In Antisocial personality disorder, individuals must be age _____ for diagnosis and have a history of ______ prior to age 15.
≥18 conduct disorder *DDx:* - Borderline personality disorder (exploitative behaviors related to abandonment fears) - Conduct disorder (pattern of violating societal norms & rights of others; age <18) - Narcissistic personality disorder (no pattern of violence or criminal activity)