UWorld Review - Part 1
Attack rate
# of people who became ill / # of individuals at risk for contracting that illness
Keratin contains which AAs?
Alanine, glycine --> small, form lots of H bonds. Cysteine - disulfide bonds give rigidity and toughness
1° biliary cirrhosis (florid duct lesion)
Autoimmune destruction of bile ducts, middle aged women, pruritis is first sx followed by fatigue, hepatosplenomegaly, xanthelasmas, jaundice, portal HTN, osteopenia
What is the major difference b/n rubeola (measles) and rubella?
Both have rash starting on face and descending, but only rubella has postauricular lymphadenopathy and tenderness.
Paneth cells
Both phagocytic and secretory, in small groups at base of intestinal crypts, secrete lysozyme (dissolves bact cell walls) and defensins, first line of defense against microorganisms
CMV-rel complications in infants exposed to CMV in utero
Chorioretinitis, sensorineural deafness, sz, jaundice, hepatomegaly, splenomegaly, microcephaly
von-Hippel Lindau dz
Chrom 3, mutation of VHL. Sx: renal cysts, renal cell carcinomas, hemangioblastomas of the cerebellum and retina
How do chronic anemia and anaphylaxis affect CO/VR curves?
Chronic anemia - inc CO to meet metabolic demand, slight inc in VR due to dec viscosity. Anaphylaxis - third spacing causes dec VR, inc CO to maintain BP
Inc CO, dec TPR (inc slope of cardiac fcn and VR curves), inc SBP
Chronic arteriovenous fistula
Prolonged pruritis and fatigue, later acholic stools and ADEK malabsorption from reduced bile flow to small intestine
Chronic cholestatic processes (1° biliary cirrhosis, 1° sclerosing cholangitis)
Effect of chronic diarrhea on kidney stones
Chronic diarrhea impairs bicarb reabsorption from gut --> chronic metabolic acidosis --> inc bicarb resorption in kidney, H+ secretion --> inc tubular acidity causes uric acid precipitation
Why does alcohol w/d from chronic etoh use cause sz/DTs?
Chronic ethanol use causes downreg of GABA-R and upreg excitatory NMDA-R in brain. Most common initial finding is tremors
Postprandial epigastric pain and assoc food aversion/wt loss
Chronic mesenteric ischemia (diminished blood supply esp prominent 1 h after meals)
Cirrhosis
Chronic methotrexate ingestion for RA
Pseudodementia
Cognitive impairment assoc w/ depression
Treatments to minimize s/e of chemo
Dexrazoxane ~ doxorubicin-induced cardiotox, MESNA ~ ifosfamide, leucovorin ~ MTX, ondansetron ~ N/V, filgrastim ~ neutropenia
Young patient develops ADHF after sxatic viral prodrome (fever, sinus congestion, myalgias)
Dilated cardiomyopathy due to viral myocarditis (may be coxsackie, influenza, adenovirus). Inadequate immune response allows virus to persist inside cardiomyocytes, resulting in damage
Where is coarct of aorta most common?
Distal to L subclavian a (juxtaductal)
Mechanism of N/V in levodopa use
Dopamine stimulates emetic center in brainstem
Double bubble sign
Duodenal atresia, assoc w/ Down's
Melanoma vs atypical (dysplastic nevi)
Dysplastic nevi resemble melanoma but have less extreme features, form coalescing nests and fuse into continuous layer at DEJ
Sx of acute transplant rejection
Dyspnea on exertion, PND (like those found in heart failure from systolic dysfunction)
Superior vena cava syndrome
Dyspnea, cough, swelling of face, neck, and UE, HA, dizziness, elev ICP, dilated collateral vv. Due to mediastinal mass (lung cancer)
Aortic valve calcifications
Dystrophic calcifications ~ cell necrosis, due to endothelial and fibroblast death, NORMAL CA. Elev Ca assoc w/ metastatic calcification
Action of dystrophin
Dystrophin links with actin fibers and reinforces glycoprotein complexes in PM of SMCs. Dysfcn leads to sarcolemmal breakdown, muscle fiber degen
Appearance of granulomas in Churg-Strauss
Eosinophilic infiltration and prominent areas of necrosis
Steps in hepatic processing of bilirubin
1) Carrier med uptake of bilirubin at sinusoidal memb, 2) conjugation to glucuronic acid by UGT in ER, 3) biliary excretion of water soluble bilirubin glucuronides
Muscles used when sitting up from supine pos
Ext abdominal obliques, rectus abdominis, psoas major, iliacus
What enzyme in the TCA/ETC requires riboflavin?
FMN is component of Complex I, FAD is component of complex II (succinate dehydrogenase). Also succinate to fumarate in TCA requires FAD
Mechanism of Factor V Leiden
Factor Va Leiden has reduced susceptibility to cleavage and inactivation by APC --> inc thrombin
Truncus arteriosus is due to what?
Failure of conotruncal septation
Duodenal atresia
Failure of recanalization of the intestinal lumen, assoc w/ Down's
How do different antihypertensives affect PRA?
ACE-I and ARB block RAAS --> should cause feedback inc in renin. Diuretics induce hypovol --> dec RBF --> feedback inc in renin. Beta blockers and clonidine dec symp stim --> dec renin.
Which antihypertensive is CI in pregnancy and causes Potter's?
ACE-I or ARB --> low ATII can result in fetal renal maldevelopment --> reduced diuresis and oligohydramnios --> Potter sequence. Also causes dec cranial vascularization and hypocalvaria
Which drug causes transient inc in Cr and serum K when started?
ACE-I. Efferent arteriolar dilation --> dec GFR. Not a problem unless Cr inc by more than 30%
Which meds improve long-term mortality in HFpEF?
ACE-I/ARBs
After Breakfast Lunch, Please Forgive Me (ABL PFM)
ACL inserts laterally, prevents backward motion of femur on tibia; PCL inserts medially, prevents forward motion of femur on tibia (in other words, prevents backward motion of tibia on femur). Or, LAMP (lateral ACL, medial PCL)
Osler-Weber-Rendu syndrome (hereditary hemorrhagic telangectasia)
AD, congenital telangectasias. Rupture leads to epistaxis, GI bleeding, hematuria
Causes of Vit K def
Fat malabsorption, taking broad-spectrum abx
Cystatin C
Filtered in glom, no active reabsorption, metabolized by renal tubular cells --> variable urinary excretion
Lanugo
Fine hair assoc w/ inadequate nutritional intake. In anorexia, dec adipose tissue/fat reserves leads to dec leptin and dec GnRH release from hypo
Cause of presyncope starting ACE-I in pt on HCTZ
First dose hypotension
Hemoglobin types
First few weeks of embryogenesis - zeta and epsilon, HbF at 8 weeks gestation (a2g2). HbF declines at birth, gradually replaced by a2b2 by 6 mo.
Capillary hemangioma course
First grow rapidly, and spontaneously regress by 5-8 yrs
Dengue fever
Flavivirus - high-grade fever, HA, retro-orbital pain, bleeding, diffuse macular rash, muscle and jt pain, thrombocytopenia, elev LFTs. Many serotypes, 2° infection is worse
PPO
Flexible for in-network and out-of-network providers, but high premiums and deductibles compared to HMO
ZES
Gastrinomas are in small intestine or pancreas. Multiple peptic ulcers beyond the duod bulb (duod ulcers are rarely malig), refractory to therapy, abd pain and acid reflux, diarrhea (as gastric acid damages intestinal epith cells and inactivates panc enzymes)
Location of carcinoid tumors
Gastrointestinal tract (small intestine, rectum, appendix), followed by bronchopulm system. Cells of uniform size and shape in islands.
Which zone is missing in patients w/ XLA?
Germinal centers
Brain regions suppled by ant choroidal a
Post limb of int capsule, optic tract, lat geniculate body, choroid plexus, uncus, hippocampus, amygdala
What medication is given after nuclear reactor accident (131I)?
Potassium iodide --> prophylactically protect the thyroid from excessive accum of radioactive 131I (competitive inhibition).
Relationship b/n potency and MAC
Potency = 1/MAC. MAC is %age of anesthetic in the inspired gas mixture that renders 50% of pts unresponsive to painful stimuli (intrinsic prop of anesthetic, dec w/ age)
Characteristics of anesthetics
Potency ~ MAC, solubility ~ blood/gas partition coef ~ CamvX. High blood/gas partition coef --> absorbed to greater extent by blood --> slower onset of action. High CamvX --> more extraction into tissues --> slower onset of action
1 h old full-term, flattened nose (Potter facies), bilat club feet, tachypnea, variable decelerations from compression of umbilical cord during labor
Potter sequence
Factors that decrease PRA
Primary hyperaldosteronism, high sodium diet
Gracilis vs cuneatus
GraciLis - lower body, legs; cUneatus - upper body, arms
Diseases that cauase nephrolithiasis
Primary hyperparathyroidism ~ hypercalciuria, Crohn's dz ~ hyperoxaluria, Type I RTA ~ hypocitraturia, gout ~ hyperuricosuria
Primary vs secondary pulm HTN difference
Primary is due to intrinsic inc in resistance of pulm vasc (PAH), secondary is due to L-sided heart failure, chronic lung hypoxia etc.
Five CDC steps to reduce central venous catheter infections
Hand hygiene, maximal barrier precautions (surgical mask), chlorhexidine antiseptic preparation of site, use subclavian/IJV instead of femoral, prompt catheter removal
Which hemoglobin moves slowest?
HbS
Maple syrup urine dz (branched chain alpha-ketoacid dehydrog def)
I Love Vermont maple syrup from maple trees with b1ranches (isoleucine, leucine, valine)
Neonatal tetanus (tetanus neonatorum)
Introduction of C tetani spores to infant from unhygenic deliveries or cord care, seen in developing countries. Sx start 5-7d after birth: difficulty feeding, trismus, spasms and hypertonicity, clenched hands, dorsiflexed feet, opisthonotus, eventual resp failure (100% mortality w/o tx). Tx: supportive care, abx and tetanus Ig. Prevention: immunization of pregnant women, hygenic delivery and cord care
Neuropeptide Y
Involved in appetite and pain perception, potential antiobesity drugs
BRCA1/2
Involved in dsDNA break repairs, AD, 70-80% lifetime risk of breast cancer, also ovarian and prostate cancer risk
Failure of hindgut descent
Imperforate anus
Funtions of patella
Improves knee extension (quadriceps tendon inserts on it), protects from direct injury, and nourishes distal femur articular cartilage
Severe R sided eye pain after meds for inf MI
Inf MI --> blockage of RCA, which feeds SAN and AVN --> bradycardia, tx is atropine --> atropine can cause acute closed-angle glaucoma
Branches of ext iliac a
Inf epigastric a (supplies lower abd wall) and deep circumflex iliac a
Why are pts not protected from reinfection by N gonorrheae?
Infection leads to formation of IgA and IgG Abs, but high variability of gonococcal surface Ags (porins, Opa prots, LOS) limits effectiveness of Ab response. Previous Neisseria infection results in no protective immunity against future infections
Brain regions supplied by ACA
Inferior frontal, medial frontal, superior medial parietal lobes; ant 4/5th of corpus callosum; olfactory bulb and tract; ant portion of basal ganglia; int capsule
Fitz-Hugh-Curtis syndrome
Inflam of peritoneal cavity due to PID
Pathology of endometritis
Inflammatory infiltration of endometrial glands. Tenderness, fever, tachycardia
Alpha-amanitin, found in Amanita phalloides
Inhibits RNA pol II, causes severe hepatotoxicity if ingested.
Keloids vs hypertrophic scars
Keloids - fibroblasts, myofibroblasts, and Col fibers are disorganized; hypertrophic - parallel. Keloids produce TGFbeta excessively w/o regulation
Reserpine
Inhibits dopamine entry into presynaptic vesicles, causing chemical sympathectomy. Reduces BP and HR
Cycloserine
Inhibits incorporation of D-alanine into UDP-MUrNAc-oligopeptide during bacterial cell wall syn, has high level of ototox
Innervation of int vs ext hemorrhoids
Int - covered by columnar epith, innerv by inf hypogastric plexus (stretch and not pain), ext - modified squamous epith, innerv by pudendal (inf rectal)
Inc in Staph bloodstream infections is due to what?
Intravascular devices/catheters (normal skin flora bacteria such as S aureus and coag-neg Staph). Before 1980s, Gram-neg aerobes were most common cause of healthcare-assoc bloodstream infections
Germinal matrix fragility
Intraventricular hemorrhage in premature infants. Germinal matrix begins to involute at 28 weeks gestation and disappears by full term
Apoptosis
Intrinsic - cells damaged by UV light, heat etc. display intrinsic apoptotic signals (phosphatidylserine, thrombospondin) on cell memb. Dec BCL-2 --> mito permeability transition (MPT), release of cytochrome c into cytoplasm
Low dose vs high dose epi (epi b1=b2>a1)
Low dose: b2 > a1 --> diastolic BP dec, high dose: a1 > b2
Presentation of severe coarctation of the aorta
Lower extremity cyanosis
Cauda equinal syndrome
Massive rupture of IVD that compresses two or more of the 18 spinal roots of the cauda equina (low back pain radiating to legs, saddle anesthesia, loss of anal wink reflex)
Causes of angioedema
Mast cell activation (associated pruritis and urticaria) vs excess bradykinin (ACE-I, C1 esterase inhibitor def, no pruritis or urticaria)
Childhood rash that causes encephalitis
Measles (SSPE)
Methionine and homocystinuria
Methionine --> SAM (methyl donor) --> S-adenosyl-homocysteine --> adenosine + homocysteine --> (cystathionine synthase, serine, B6) --> cystathionine --> (cystathionase, B6) --> cysteine
Which medications are first line antihypertensives in pregnancy?
Methyldopa (alpha-2 agonist) and labetalol (beta-adrenergic antagonist)
Tx of migraines
Metoclopramide and sumitriptan to abort acute migraines, topiramate is effective tx for prevention of chronic migraines
Histology of dermatitis herpetiformis
Microabscesses containing fibrin and neutrophils at the dermal papillae tips --> blisters form at tips of involved papillae
Triad of HUS (E coli O157:H7)
Microangiopathic hemolytic anemia, thrombocytopenia, renal insuff
Triad of hemochromatosis (body Fe levels > 20 g)
Micronodular cirrhosis, diabetes mellitus, bronze diabetes (skin pigmentation) --> inc risk of HCC, CHF, testicular atrophy/hypogonadism
Hemoglobin C
Mutation in beta-globin chain causing glutamate to be replaced by lysine, forms hexagonal crystals and promotes RBC dehydration --> chronic hemolytic anemia
Hereditary pancreatitis
Mutations involving trypsinogen or SPINK1. Most common mut leads to prod of abnml trypsin that is not susceptible to inactivating cleavage by trypsin
Postpartum woman w/ worsening dyspnea, normal phrenic n
Myasthenia gravis (progressive attenuation of intrapleural pres change on deep inspiration, b/c ACh stores are depleted)
Resistance to ethambutol
Mycobacteria inc production of arabinosyl transferase (enzyme in synthesis pathway of mycobacterial cell wall)
PATHOPHYSIOLOGY OF COLD AGGLUTININS IN MYCOPLASMA
Mycoplasma attacks the respiratory epithelium by binding to an oligosaccharide (I-antigen) that is also present on the surface of RBCs. This leads to formation of cross-reacting IgM Abs that attach to RBCs, activate complement, and cause RBC lysis --> intravascular hemolytic anemia. Anemia resolves when IgM titers disappear (fall 4 wks after infection, gone by 8 wks)
What do SCLC stain for
NCAM (CD56) b/c small cell has neuroendocrine origin. Also neuron-specific enolase, chromogranin, synaptophysin.
What is the primary mediator of COPD?
Neutrophils (think neutrophil elastase). Also macrophages and CD8+ T lymphocytes
Atypical/silent GERD
Nocturnal cough, hoarseness, asthma, laryngitis, chest pain, globus, dental erosions IN ABSENCE of heartburn
Carbamoyl transferase def
OTC def results in excess carbamoyl phosphate, increasing urinary orotic acid hyperammonemia
Imperforate hymen (hematocolpos)
Obstructive lesion caused by incomplete degen of hymen. At birth, vaginal secretions stim by mother's estrogen cause mucocolpos (accum of mucus in vaginal canal) --> bulging introitus. Should be dx at tha time.
Effect potentiation
One drug's ability to inc the pharmacologic effect of another agent (e.g., beta blockers and nitrates co-prescribed)
Extra effect of PTU over methimazole
PTU decreases the peripheral conversion of T4 to active T3, methimazole does not
Seat belt, steering wheel, MVA injuries
Pancreatic injury. Retroperitoneal = SAD PUCKER
Migratory superficial thrombophlebitis (Trousseau syndrome)
Paraneoplastic syndrome seen in visceral adenocarcinomas of the panc, colon, and lung. Hypercoag b/c adenocarcinomas prod thromboplastin-like subsance
Filariasis
Parasitic dz caused by infection w/ roundworms, spread by black flies and mosquitos, causes lymphatic obstruction
Insulin secretion and receptors
Parasymp stim of muscarinic M3 promotes insulin secretion (induced by smell/sight of food), histamine H2 stim inc insulin secretion, beta2-stim promotes insulin secretion, alpha2-stim inhibits insulin release (a2 > b2, so epi inhibits insulin secretion)
MOA of varenicline
Partial agonist of a4b2-nAChR --> competes w/ nicotine, reduces w/d cravings and attenuates reward effects of nicotine
Holoprosencephaly
Patau (trisomy 13). Myelomeningocele ~ trisomy 18, omphalocele ~ trisomy 13 and 18
Contraindications to bupropion
Patients with bulimia nervosa, anorexia nervosa, sz d/o due to its lowering of the sz threshold
Capitation
Payor (individual, gov't entity, employer) pays a fixed, predetermined fee to cover all medical services required by a patient
Induration and swelling over one breast
Peau d' orange, inflam breast cancer, obstruction of lymphatic drainage. Can be mistaken for mastitis, but former has no fever or generalized sx
Mutated porin protein is resistance mechanism against which abx
Pencillins and aminoglycosides
Ansa cervicalis is frequently injured when?
Penetrating trauma to neck above cricoid cartilage
TTP-HUS
Pentad of fever, neurologic manifestations, acute renal failure, thrombocytopenia, microangiopathic hemolytic anemia. TTP - adults, neuro sx. HUS - children, kidney. Isolated activation of platelets, coag factors normal. No bleeding
Intense itching after hot shower
Polycythemia vera. Also p/w erythromelalgia (severe, burning pain and red-blue discoloration)
Causes of 2° TB and miliary TB
Former - Acquired immunosupression (HIV, TNF-a inhibitors), p/w wt loss, cough, fever, apical cavitary lesions. Latter - ineffective immunity (extremes of age, immunosuppression), hematogenous spread (Potts, meningitis)
Howell-Jowell bodies and Pappenheimer bodies
Former - DNA, splenectomy; latter - iron, sideroblastic anemia
Why is fructosuria benign, and hereditary fructose intolerance bad?
Former - Fructokinase deficient, so hexokinase can convert fructose to F-6-P and shunt down glycolysis. Fructose is also excreted unchanged in urine. Latter - aldolase B deficient, and fructose-1-P accumulates (toxic) --> liver failure
HIV drugs assoc w/ myelosuppression
Ganciclovir, TMP/SMX, zidovudine
Rett syndrome
X-linked dominant, affected males die in utero, prog neurodegen, deceleration of head growth, stereotypical hand movements
Macula
Yellow spot in center of retina, contains densely packed cones, few overlying cells, no BVs. Each macular cone synapses to single bipolar cell. Visual acuity of macula and fovea is highest in all of retina
Most common cause of orchitis
Young adults - Chlamydia trachomatis and N gonorrhoeae, old - E coli
Pseudotumor cerebri
Young obese women w/ daily HA, bilat symmetric papilledema, transient visual disturbances. Due to impaired cerebral venous outflow, and elev ICP. Impaired axoplasmic flow w/in optic nerves
Rugal thickening w/ acid hypersecretion
ZES
Zero-order vs first-order kinetics
Zero-order ~ same amt metabolized (20 mg dose is 10-10, 40 mg dose is 30-10). First order ~ same proportion metabolized (20 mg dose is 10-10, 40 mg dose is 20-20)
Example of lipooxygenase inhibitor
Zileuton - dec prod of pro-inflam LTs in asthma
Which layer of the adrenal is not ACTH dependent?
Zona glomerulosa (controlled by ATII). Hence, Cushing's does not cause glomerulosa hyperplasia!!
What happens to tubular [inulin] along tubular sys?
[Tubulin] inc although amount stays the same, due to net water reabsorption
Causes of Ehlers-Danlos
Problem with proteolytic processing (N-terminal propeptide removal) or crosslinking of staggered tropocollagen to make collagen fibrils
Which drugs are metabolized by phase II acetylation in liver?
Procainamide, hydralazine, isoniazid
TNF-alpha
Produced by Mo and T cells, maintains granuloma formation, imp for host defenses against TB
Androgen-binding protein
Produced by Sertoli cells in response to FSH, found locally, responsible for high local T concentration and is different from SHBG (found in blood)
Causes and jugular venous findings of constrictive pericarditis
Radiation therapy to the chest, cardiac surgery, TB. Rapid y-descent
Tx of insonmia IN ELDERLY PT
Ramelteon (melatonin receptor agonist), few s/e and safe in geriatric pts. Benzos are CI in elderly due to inc risk of delirium, falls, fractures
Two examples of tachyphylaxis
Rebound rhinorrhea from nasal decongestants (alpha agonists), and nitroglycerin
Tenesmus and small-caliber stool
Rectal adenocarcinoma
Carbidopa
Reduces peripheral conversion of levodopa to dopamine and minimizes systemic s/e
Atrial flutter
Reentrant current rotating around the tricuspid annulus
What are the 3 phases of ATN?
Refer to FA p.587. Recovery phase characterized by re-epithelization of tubules, tubular cells recover gradually, resulting in transient polyuria and loss of electrolytes. Complete restoration of fcn in most pts
Mechanism of lac operon action
Repressor prots bound to operator prevent binding of RNA pol to promoter region, thus dec transcription of structural genes
Common presentations of sup sulcal tumor (Pancoast)
Shoulder pain (compression of brachial plexus), Horner's (involvement of cervical symp ganglia), SVC syndrome
Wedge-shaped, capsule-based splenic infarcts
Sickle cell anemia, infective endocarditis, cardiac mural thrombosis
Scurvy
Skin and mucosal hemorrhaging, intraarticular bleeding, gingival swelling, impaired wound healing, weakened immune sys, perifollicular hemorrhages, coiled (corkscrew) hairs
Where do DHP CCB act?
Small arteries and arterioles in peripheral and coronary circ
Patellar ligament
Spans from patella to tibial tuberosity - continuation of quadriceps femoris tendon
Fibroids located in which location are most likely to bleed?
Submucosal - prolonged or heavy menstrual bleeding
Meissner and Auerbach
Submucosal and myenteric, respectively
In exercise, why do you get overall dec in SVR?
Substantial arteriolar vasodil in skel muscle due to adenosine, K, ATP, lactate, CO2 release locally. Everywhere else, symp stim causes vasoconstriction to shunt blood to active skel muscle
Walls of the orbit
Sup - thick orbital plate of frontal bone, lat - zygoma and greater and lesser sphenoid wings, floor - air-filled maxillary sinus, med - ethmoid and lacrimal bones (ethmoid air cells)
Herring bodies
Termination of hypothalamic axons in the posterior pit (neurohypophysis), specialized nerve terminals that act as a storage site for secretory vesicles
Exceptions to superficial inguinal drainage (from umbilicus to feet)
Testes to para-aortic LNs, glans penis and cutaneous portion of post calf to deep inguinal LNs
Empty can test (abduct humerus, thumbs pointed to floor)
Testing supraspinatus (most commonly affected muscle in rotator cuff syndrome)
Pill-induced esophagitis is due to what?
Tetracycline abx, KCl, bisphosphonates
S/e of linezolid
Thrombocytopenia, optic neuritis, inc risk of serotonin syndrome
S/e of EPO stimulating agents
Thromboembolic events (vasc graft thrombosis, stroke), hypertension
Crichothyrotomy
Thru skin, superficial cervical fascia, pretracheal layers of deep cerv fascia, cricothyroid membrane
Condition most commonly assoc w/ MG
Thymoma and thymic hyperplasia
Anterior mediastinal masses
Thymoma, teratoma, thyroid cancer, (terrible) lymphoma. The Terrible T's
Iodine acquiration by thyroid
Thyroid follicular cells take up inorganic iodide using Na/I symporter --> ioidide released into thyroid follicular lumen, oxidized to iodine radical by TPO --> iodine is organified in thyroglobulin to form MIT and DIT --> form T3/T4 by coupling --> thyroid follicular cells engulf thyroglobulin by pinocytosis
Other diseases that can have +ve anti-cardiolipin
Treponemal ~ yaws, pinta, bejal, non-treponemal ~ TB, lupus
Cushing triad
Triad of HTN, bradycardia, and resp depression. Mechanism in FA
Ataxia-telangectasia
Triad of cerebellar ataxia, spider angiomas (telangectasias), inc risk of sinopulm infections. ATM gene mutation results in inability to perform DNA break repair
Renal cell carcinoma
Triad of flank pain, hematuria, and palpable abdominal mass. Spreads to lungs and bone by invasion of IVC. May cause paraneoplastic erythrocytosis/polycythemia (inc EPO) or hyperCa (inc PTHrP)
True ribs vs false ribs
True - ribs 1-7 (costal cartilage attaches directly to sternum), false - ribs 8-12, floating ribs - ribs 11 and 12
Sx of L cerebellar vermis lesion
Truncal ataxia (wide-based, unsteady gait), vertigo/nystamus - disruption of inf vermis and F-N lobe
Renal angiomyolipoma assoc w/ what
Tuberous sclerosis: cortical tubers, subependymal hamartomasi in brain (sz, cog disability), Ash-leaf patches
Acute serum sickness
Type III hypersensitivity, sx incl fever, pruritic skin rash, arthralgias that begin 7-14 d after exposure to Ag. Fibrinoid necrosis, intense neutrophil inflam, C depletion, neutropenia due to neutrophilic tissue infiltration
Allergic contact dermatitis
Type IV hypersensitivity
Leukocytes w/ monocytic predominance in stool
Typhoid fever, caused by Salmonella typhi
Which heparin (UFH, LWMH, or fonda) has most activity for thrombin?
UFH - 18 saccharide units can form ternary complex w/ AT III and thrombin, whereas LMWH cannot (only 5 saccharide units)
Negatively charged chemical found in mast cells used for DVT proph
UFH and LMWH
UMN vs LMN signs
UMN - spastic paralysis, clasp-knife rigidity, hyperreflexia, Babinski. LMN - flaccid paralysis, hypotonia, hyporeflexia, muscle atrophy and fasciculations
Causes of MCD
URTI, immunization, insect bite in children --> systemic T cell dysfcn leads to prod of glom permeability factor
Septic shock in old pt, blood cultures +ve for E coli
UTI (2° to BPH, catheter, etc.). Septic shock is due to body's reaction to LPS endotoxin
Nucleotide excision repair (removal of thymine dimers) done by what enzyme?
UV-specific endonuclease
UVA vs UVB
UVB wavelengths are absorbed in upper dermis --> sunburn, inc risk of malig. UVA - penetrate deeper into skin, photoaging. UVA prod ROS --> dec Col fibril prod and inc MMR --> degrade Col and elastin
Fall on hand, dec sensation over 5th digit, flat hypothenar eminence
Ulnar neuropathy due to fracture of hook of hamate w/ fall on outstretched hand
Presentation of Bell's palsy
Unilat facial paralysis, dec tearing, hyperacusis, loss of taste sensation over ant 2/3rds of tongue
Presentation of mesothelioma
Unilat pleural thickening or mass w/ a large pleural effusion. Asbestos exposure. Tumor cells w/ long slender microvilli and abundant tonofilaments
Temporomandibular disorder
Unilateral facial pain that worsens w/ jaw movement, HA, ear discomfort
Ground coffee emesis
Upper GI bleeding from PUD
Fatigue, weakness, itching in pt w/ ESRD
Uremia
DNA binding proteins detected by Southwestern blot
c-Jun and c-Fos, bind to DNA via leucine zipper motif
APML
t(15:17), formation of PML/RARalpha --> promyelocytic leukemia (PML) gene can't signal differentiation of myeloid precursors at physiologic doses of retinoic acid
Protein elevated in CSF of Crutzfeld-Jakob
14-3-3 protein
Febrile neutropenia
ANC < 500
Acyl CoA synthetase
Activates FAs in the cytoplasm to undergo beta-ox in mito
Function of hepcidin
Acute phase reactant. Dec iron absorption (by degrading ferroportin) and dec iron release from Mo --> anemia of chronic dz.
Epistasis
Allele of one gene affects the phenotypic expression of alleles in another gene
What causes serum sickness?
Antigenic heterologous proteins (chimeric mAbs - rituximab and infliximab), venom antitoxin, penicillin, TMP/SMX
Anti-SMC Abs
Autoimmune hepatitis
Ipsilateral hyperacusis
Common finding in Bell's palsy
Where does pleural exudate accumulate?
Costodiaphragmatic recess
S/e of ACE-I
Cough, angioedema, hyperK
Homeobox genes code for what?
DNA binding transcription factors that determine craniocaudal axis
BPPV
Due to otoliths in the semicircular canals. Brief episodes brought on by head movement, no auditory sx
Leukoplakia vs Candida albicans
Former cannot be easily scraped off
Aldose reductase functions
Glucose --> sorbitol, galactose --> galactitol
Methemoglobinemia
Grey or blue-colored skin, SOB, chocolate-covered blood. Tx: methylene blue
S/e of protease inhibitors
Hyperglycemia, GI sx, lipodystrophy
Most important opsonizing proteins
IgG and C3b
When do you first see b-HCG in serum? In urine?
In 7 d in serum, in 14 d in urine
Headache that worsens w/ Valsalva
Inc ICP
Hydroxyurea and SCD
Increases HbF synthesis
Subluxation of radial head
Injures deep branch of radial nerve, weakness during finger and thumb extension (finger drop)
Medium-chain acyl-CoA dehydrog def
Lethargy, sz, hypoketotic hypoglycemia after fasting
Basement membrane splitting in nephritic syndrome
MPGN (tram tracking)
Multiple sclerosis and urinary incontinence
MS causes overactive/spastic bladder due to presence of UMN lesion in SC --> bladder cannot relax/distend properly due to loss of descending inhibitory control, no PVR
Intermittent posturing episodes in 4 d old infant, carmelizing sugar diapers
MSUD, I Love Vermont maple syrup (with B1ranches) --> give thiamine
Congenital hydrocephalus
Macrocephaly, poor feeding, muscle hypertonicity, hyperreflexia
Immune response to mycobacteria
Macrophages (imp for elim intracell infections) infected w/ mycobacteria produce IL-12 --> stimulates T cells to prod IFN-g --> IFN-g binds to receptor on Mo, JAK/STAT signaling
Candida skin test mechanism
Macrophages present Candida Ag to CD4 T cells --> CD4 recruit CD8, and both produce IFN-g prompting Mo to phagocytose Candida. Anergy to candida suggests SCID
ALS (middle aged people, progressive course, resp complications cause death, die w/in 5 yrs of dx)
Macroscopic ~ thin ant roots, mild atrophy of precentral gyrus; microscopic ~ loss of ant horn neurons (LMN), degen and atrophy of lat corticospinal tracts (UMN), genetic ~ mut of copper-zinc SDM (SOD1), tx: riluzole (dec glutamate release)
Trehalose dimycolate
Major virulence factor of M tb
Asymmetric IUGR
Maternal HTN (normal head size w/ reduced abdominal circumference)
Vit A def predisposes to what dz
Measles
Vasa vasorum narrowing in chronic HTN
Medial ischemia of aorta and aneurysm formation
Cystic dilation of CDs
Medullary sponge kidney, w/ medullary cysts seen
Rugal hypertrophy w/ parietal cell atrophy and dec acid secretion
Menetrier disease
Obturator nerve injury
Pelvic trauma, surgery, tumors (bladder cancer)
Which drugs dec peripheral conversion of T4 to T3?
Propranolol, glucocorticoids, PTU
Loud P2
Pulmonary hypertension
Cryptococcal meningitis
Slowly worsening HA, fever, confusion
Tx of Conn's syndrome and s/e of drug
Spironolactone/epleronone. S/e is gynecomastia
Saccular aneurysm rupture
Subarachnoid hemorrhage
Where do the intercostal v, a, and n run?
Subcostal groove on the lower border of the rib. Thus, perform thoracocentesis just above upper border of rib
Which structure must be ligated to prevent heavy bleeding in oophorectomy?
Suspensory ligament of ovary (contains ovarian a, v, lymphatics, and n)
Brain areas most affected by AD
Temporoparietal lobes, esp hippocampus
Tx of nephrogenic DI
Thiazide diuretics (induce mild hypovolemia, inc prox tubular Na and water reabsorption), indomethacin (dec syn of PGs, which inhibit ADH)
Which antihypertensive improves BMD and prevents osteoporosis?
Thiazides - inc Ca reabsorption
Pectineal (Cooper's) ligament
Thickened part of pectineal fascia, overlies pectineal ridge of pubic bone and post to femoral canal
Thoracic outlet syndrome (occurs in scalene triangle)
Thoracic outlet is the space above the first rib and behind the clavicle. Compression of lower trunk of brachial plexus --> UE numbness, tingling, weakness, compression of subclavian v ~ UE swelling, compression of subclavian a ~ exertional arm pain
Triad of Wiskott-Aldrich
Thrombocytopenia, immunodeficiency, eczema
Troponin binding
Troponin I - binds to actin, Troponin T - binds to tropomyosin, Troponin C - binds Ca. Troponin binds tropomyosin to actin
What happens in first few weeks of M tb infection?
Uncheck replication w/in phagosome of alv Mo, alv Mo cannot degrade b/c of virulence factors (cord factor)
Sx of Crigler-Najjar
Unconj bilirubin can't be filtered by kidney --> builds up in tissues. Muscle rigidity, lethargy, sz, jaundice, neuro impairement, kernicterus (bilirubin encephalopathy)
When do children develop gender identity?
Understanding of concept of gender by age 3-4, and have sense of permanency of gender by age 5-6
Sentinel event
Unexpected occurrence involving death or serious physical or psych injury (inpt suicide, death of full-term infant) that requires immediate investigation
Pancreas divisum
Ventral and dorsal parts fail to fuse at 8 wks. Normally, prox part of accessory duct degen and remainder fuses w/ ventral duct to form main duct of Wirsung. In divisum, dominant duct (of Santorini) drains majority of panc via minor duod papilla, and smaller ventral duct (of Wirsung) opens via major duod papilla. Mostly asxatic, may cause chronic abd pain and/or pancreatitis
Which Vitamin deficiency is associated w/ measles?
Vitamin A
Squamous metaplasia in panc ducts of CF pt due to what?
Vitamin A deficiency (CF --> fibrosis of panc, panc insuff --> malabsorption of ADEK). Vit A needed to maintain orderly differentiation of specialized epithelia
Which dz causes cystic degeneration of the putamen?
Wilson's disease
Straight leg raise
Worsens radicular pain when sxatic leg is extended at the knee and hip is passively flexed. Sciatica = L4-S3 roots, commonly L5-S1
Thymidylate synthase function
Converts dUMP to dTMP, requires THF. Deficiency results in inc dUMP/dTMP ratio --> incorporation of uracil into DNA by erythrocytes --> excessive action of DNA repair, apoptosis of hematopoietic stem cells and megaloblastic anemia
Ribonucleotide reductase
Converts ribose sugars to their deoxyribose forms for use in DNA syn
Copper excretion
Copper is incorporated into a2-globulin to form ceruloplasmin --> resecreted into plasma. Ingested, unabsorbed copper is secreted into bile and into stool
Consequences of cystinuria in intestine
Defective transporter results in absent intestinal absorption of COLA AAs, but AA deficiencies do not develop b/c they are absorbed in suff quantities via oligpeptides
Type III hyperlipoproteinemia
Defects in ApoE3 and E4 (cannot remove chylomicron and VLDL remnants)
Which enzyme's activity is inc in Lesch-Nyhan?
Deficiency of HGPRT (purine salvage pathway to convert hypoxanthine back to IMP, and guanine into GMP) --> inc demand for de novo purine syn --> inc PRPP amidotransferase activity
Hartnup disease
Deficiency of neutral amino acid transporter in PCT (tryptophan, precursor for niacin and serotonin) --> pellagra like sx, cerebellar ataxia, neutral aminoaciduria. Treat with niacin supplementation
Functions of deep vs superficial peroneal n
Deep - ant compartment (dorsiflex foot and toes), sensation to webspace b/n 1st and 2nd toes. Superficial - lat compartment (eversion), sensory to dorsum of foot and lat shin
Kussmaul breathing
Deep and labored breathing pattern. Ketones (DKA), uremia, sepsis, salicylates, methanol aldehydes, U, lactic acidosis
Midshaft humeral fracture in setting of radial nerve deficits
Deep brachial a
Areas most affected by Charcot-Bouchard aneurysms
Deep brain structures: Basal ganglia (putamen), cerebellar nuclei, thalamus, pons. Aneurysm leads to intraparechymal hemorrhage, HYPERDENSITY on CT (vs hypodensity of ischemic stroke)
Tuberous sclerosis
Defect TSG hamartin (TSC1) and tuberin (TSC2), characterized by cutaneous angiofibromas, brain hamartomas, cardiac rhabdomyomas
Hemoglobin H and Barts
Defect in syn of alpha chains results in alpha thal, characterized by formation of beta-globin and gamma-globin tetramers, respectively. Extremely high oxygen affinity (resembling myoglobin), ineffective at O2 delivery to tissues
Pathophysiology of Patau
Defect in the fusion of the prechordal mesoderm (integral structure affecting growth of midface, eyes, and forebrain)
Zellweger syndrome
Defective peroxisomal biogenesis; presents in early infancy, craniofacial abnormalities (widened sutures, large ant fontanelle), hepatomegaly, neuro defects (hypotonia, sz)
Presentation of glucagonoma
Dermatitis (NECROLYTIC MIGRATORY ERYTHEMA - elev, painful and pruritic rash that coalesces to form indurated brown plaques), diabetes (hyperglycemia), DVT, declining wt, depression. Tx: octreotide, surgery
Pyroxidone deficiency sx
Dermatitis, stomatitis, neuropathy, confusion
Structures that drain into inf mesenteric LNs
Descending and sigmoid colon, upper part of rectum
Pressure tracings of AR
Descrescendo diastolic murmur, loss of aortic dicrotic notch (immediate backflow of blood into LV), steep diastolic decline of aortic pres, wide pulse pres (LV compensates for regurgitant backflow by inc SV)
Glutathione-S-transferase
Detoxification of some chemical carcinogens, converts toxic substances into active metabolites
Aspergilloma (mycetoma)
Develop in old lung cavities (TB, emphysema, sarcoid) --> Aspergillus colonizes the cavity and forms a fungus ball w/o lung tissue invasion --> hemoptysis, shifts on CXR when the pt moves
Beck triad of tamponade
Distant heart sounds, elev JVP, hypotension. On Echo, tamponade shows pericardial fluid accum w/ late diastolic collapse of R atrium (due to displacement of pericardial fluid by vent expansion)
RAS gene
Family of small G-prots involved in MAPK/Ras pathway, inactive GDP bound or active GTP bound. RTK --> activated Ras --> MAPK --> gene transcription. Ras has intrinsic GTPase activity that prevents accum of active Ras; cancers mutate and dec GTPase activity
NF-kB (self-limiting, stimulates transcription of more IkB to rebind free NF-kB)
Family of transcription factors in immune response to infection and inflam. Normally inactive and bound to IkB. EC signal (binding of bacteria to TLR) --> activation of IkB kinase --> ubiquitination of IkB, free NF-kB enters nuc and synthesizes cytokines, acute phase reactants etc.
Extrinsic pathway of apoptosis
Fas-R has cytoplasmic death domain, found on T-lymphocytes --> binds FasL, receptors trimerize --> caspases 8 and 10 initiated
RFs for cholelithiasis
Fat, fertile, female, forty, feathers. Estrogen - inc chol syn by upreg HMG-CoA reductase, prog - reduces bile acid secretion, slows gallbladder emptying
Liver findings
Fatty change ~ alcohol abuse, hepatic centrilobular necrosis ~ ischemic injury, drugs, toxins, poral inflam ~ alcoholic hepatitis, viral hepatitis, periportal hepatic fibrosis ~ chronic viral hepatitis
Sx of pudendal n injury
Fecal incontinence, urinary incontinence, perineal pain, sexual dysfcn
Campylobacter facts
Fecal-oral transmission, "corkscrew" movement, enteric pathogen transmitted from domestic animals (cattle, sheep, dogs, chickens) to humans
Which hemoglobin is predominant in pts w/ beta-thal?
Fetal Hb (a2g2), also some A2 (a2d2) to compensate for impaired beta globin fcn
Deformations
Fetal structural anomalies that occur due to extrinsic mechanical forces. E.g., uterine constraint on fetus causes DDH
FEVER VS HEAT STROKE
Fever - elev hypothalamic set pt, febrile sz (benign), tx: supportive care (NO ACTIVE COOLING). Heat stroke - heat prod exceeds heat dissipation, normal hypo set pt, permanent end-organ damage, tx: rapid external cooling
Acute hemolytic transfusion reaction
Fever and chills, hypotension, hemoglobinuria, Type II hypersensitivity. Another type of Type II is Rh incompatibility, also warm/cold agglutinin disease
West Nile virus (acute confusion, fever, acute-onset asymmetric paralysis is pathognomonic)
Fever, HA, rash (maculopapular/morbiliform), neuroinvasive (meningitis, encephalitis, acute flaccid paralysis, Parkinsonian sx), transmission by mosquitos in summer/fall, risk factors: older age, malig/organ transplant
Toxic shock syndrome
Fever, V, D, muscle pains, erythroderma (diffuse macular rash resembling sunburn), assoc w/ tampons. SuperAg of Staph aureus --> widespread Mo and T lymphocyte activation
Adenovirus gastroenteritis
Fever, watery diarrhea, outbreaks less common, pharyngoconjunctivitis and coryza (runny nose, nasal congestion)
Detrans facilitate bacterial binding to what?
Fibrin-platelet-aggregates --> endocarditis
Cellular/myxoid stromal prolif compressing the ducts to slits
Fibroadenoma of breast (most common benign tumor of breast, young women age 15-35). Inc in size during preg, lactation and regress after menopause
String of beads appearance, RAS
Fibromuscular dysplasia, young women
Holoprosencephaly is an example of what?
Field defect - initial embryonic disturbance leads to multiple malformations by disrupting development of adjacent tissues in the region. Caused by genetic (trisomy 13, SHH mut) and env (maternal etoh use) factors
Treatment of male-pattern hair loss
Finasteride (5-alpha reductase inhibitor)
Cutting which structure relieves carpal tunnel syndrome?
Flexor retinaculum, i.e. transverse carpal ligament. CTS p/w pain and parasthesias of first 3.5 digits, weakness of thumb abduction and opposition, atrophy of thenar eminence
Non-live
Flu (IM), pneumococcus, TDaP, polio (inactivated), Hep A, Hep A, H flu type b, HPV, meningococcus
Drugs that require protein-mediated transport into bacterial cell
Fluoroquinolones, macrolides, aminoglycosides
Myoedema
Focal muscle contraction at site of percussion - due to impaired reuptake of calcium by the SR
Generalized vs focal sz
Focal: simple or complex. Generalized: tonic-clonic, myoclonic/JME (occur w/in first hr of waking, provoked by sleep deprivation), absence. See Uworld Tables tab
Follicular, diffuse, and sinus hyperplasia (in reactive hyperplasia)
Follicular - inc in follicular size and #, sinus - sinuses enlarge and fill w/ histiocytes, diffuse - nodal architecture effaced by sheets of lymphocytes, Mo. MONOCLONAL TCR RECEPTOR REARRANGEMENT --> MALIGNANCY
Tall cell thyroid cancer, variant of papillary thy cancer
Follicular hyperplasia lined by tall epith cells, seen in older individuals, worse prognosis
Waxing and waning nontender cervical LN 3.5 cm in diam
Follicular lymphoma (most common indolent NHL), long waxing/waning course. P/w painless LN enlargement
Pulsus alternans vs electrical alternans
Former - beat by beat variation in pulse amp due to change in SBP, seen in severe LV dysfcn. Latter - large pericardial effusion/tamponade, beat by beat variation in QRS amp on ECG due to swinging of heart in pericardial fluid
Amiloride/triamterene vs spironolactone/epleronone
Former - block ENaC, latter - competitively inhibit aldosterone receptor
Use of leucovorin w/ MTX vs 5-FU
Former - bypass DHFR step, attenuate toxicity. Latter - promote formation of ternary complex w/ thymidylate synthase, potentiate toxicity
Length constant vs time constant
Former - distance over which magnitude of depol falls to 1/e (myelin inc length constant; L = Ra/Rm). Latter - time it takes for memb pot to respond to change in memb permeability (function of memb C and R, myelin dec time constant).
Pharmacokinetic drug interaction vs pharmacodynamic drug antag
Former - drugs used together in a pt may affect the absorption and elimination of each other (rifampin inc warfarin metabolism by CYP450), latter - ability of a drug to antagonize the effect of another drug (labetalol blocks norepi activity)
Frontotemporal dementia vs Alzheimer's
Former - earlier onset (50-60 vs 60-70+), initial sx are personality and behavior changes (apathy, socially inappropriate behavior vs impairment in recent memory), alered speech patterns (paucity of speech, repeated phrases - "it is what it is"), FTD is AD inheritance in 20-40%
Urticaria vs angioedema
Former - edema of superficial dermis, latter - involvement of deep dermis and subQ tissue
Chloroquine and primaquine
Former - eradicate chloroquine-sensitive plasmodia from bloodstream, but does not act on hypnozoites. Primaquine needed to kill intrahepatic stage (hypnozoites, responsible for relapses)
Rash of measles/rubella vs HHV-6
Former - from face downward, latter - from trunk upward. Rubella ~ Forchheimer spots on soft palate, measles ~ Koplik spots on buccal mucosa
Barbiturates vs benzos MOA
Former - inc duration of opening of GABA_A, benzos - inc frequency of opening of GABA_A
Digoxin's role in rate control for a-fib vs use in HF
Former - inc parasymp vagal tone, latter - positive inotropic effect
Traction vs pulsion diverticula
Former - inflam and scarring of gut wall pulls an outpouching of all gut layers (true diverticula), occurs in midesophagus due to mediastinal lymphadenitis caused by TB or fungal infection. Latter - inc intraluminal pres created during strained bowel movements, causes false diverticula (only mucosa and submucosa herniate)
Vitelline duct vs persistent urachus
Former - intestinal lumen connected to umbilicus, latter - bladder lumen connected to umbilicus
Malpractice vs preventable adverse event
Former - legal determination, tx is below accepted std of practice and caused injury/death to pt. Latter - harm to pt by act of commission or omission rather than from the underlying disease, and are the result of failure to follow evidence-based best practice guidelines
Infections caused by Hib vs nontypeable H flu
Former - meningitis, bacteremia, pneumonia, epiglottitis, septic arthritis. Latter - bacterial conjunctivitis, AOM, sinusitis
Congenital vs acquired pyloric stenosis
Former - multifactorial, 2° to hypertrophy of pyloric muscularis mucosae. Latter - gastritis, peptic ulcers in the pylorus, neoplasm (carcinoma of pyloric region or lymphoma)
Cardiac embolism vs carotid artery stenosis
Former - multiple infarcts w/ different vasc territories, not bilat and symmetric in watershed zones. Latter - unilat infarcts
Permissiveness/potentiation (one drug has no intrinsic effects) vs synergism (both drugs have similar actions)
Former - one hormone allows another to exert its maximal effect (cortisol upreg a1-AR on vasc SMC; in adrenal insuff, low cortisol causes hypotensive crisis by dec vasc responsiveness to AII and norepi)
Chronic tic d/o vs Tourette syndrome
Former - one or more motor OR verbal tics (not both) for >=1 yr. Latter - multiple motor and at least one vocal tic
Azoles vs echinocandins
Former - prevent syn of ergosterol, target cell membrane. Latter - prevent syn of b-1,3-glucans, target cell wall
Free vs RER ribosomes (attach to RER via translocon to 60S)
Former - prots in cytoplasm, nucleosol, peroxisome matrix, nuc-encoded mito prots. RER - secretory prots, integral memb prots of nuc and cell memb, prots w/in ER, Golgi, lysosomes
What should you monitor w/ SGLT-I and TZD?
Former - renal fcn, latter - hepatic fcn (ADR is hepatotoxicity)
Subclinical hyperthyroidism and hypothyroidism
Former - suppressed TSH w/ normal TH levels. Latter - elevated TSH needed to maintain normal TH levels. Both are asxatic
UC associated CRC vs sporadic CRC
Former is more aggressive, arises from flat (non-polypoid) lesions, frequently multifocal (multiple synchronous carcinomas) at dx, younger pts (age 40-55), higher histopathologic grade (mucinous/signet ring cells, poorly differentiated), p53 occur early and APC occur late (opposite of AK-53), proximal > distal esp in CD (sporadic is distal > proximal)
Steps of base excision repair
GEL PLease (base-specific glycosylase removes altered base and creates AP site, nuc removed by AP-endonuc which cleaves 5' end, lyase cleaves 3' end, DNA pol beta fills gap, DNA ligase seals)
If pt has elev ALP, what do you get next?
GGT. ALP is prod in liver, bone, intestine etc. GGT is only in liver and not bone --> evaluate if elev ALP is hepatic or bony in origin
GVHD
Graft T cell sensitization to host MHC Ags, occurs after BMT or liver transplant (rich in lymphocytes), in pts that lack competent T lymphocytes. Sx: diffuse maculopapular rash on palms and soles, desquamation, diarrhea, intestinal bleeding, abd pain, abnml LFTs
What disease is common with febrile neutropenia?
Gram -ve infections --> Pseudomonas, echthyma gangrenosum (skin patches exhibiting necrosis and ulceration)
Epistaxis/nosebleed
Anterior nosebleeds more common, vast majority in watershed areas of NASAL SEPTUM. Kisselbach plexus: 1) septal branch of ant ethmoidal a, 2) lat nasal branch of sphenopalatine a, and 3) septal branch of sup labial a (branch of facial a)
Impaired visual accommodation from first gen antihistamines
Anticholinergic (antimuscarinic effects). S/e of antihistamines incl mydriasis (pupillary sphincter receives parasymp innerv from E-W nuc)
Why are IgG directed against Hep C envelope prot ineffective?
Antigenic variation. HCV has 6 or more genotypes and subtypes that vary in composition b/c virion-encoded RNA-dep RNA pol has no proofreading 3' --> 5' exonuc activity. Patients are infected w/ single genotype, but high mut rate leads to multiple quasispecies over time (strains differ at hypervariable genomic regions)
Functions of NADPH
Antioxidant in cells experiencing high oxidative stress, synthesis of FAs and chol, respiratory burst. NADPH can generate ATP from ADP (NADH can't)!
Toxins of anthrax
Antiphagocytic poly-gamma-D-glutamic capsule, anthrax exotoxin (protective Ag, EF, LF)
Function of virulence factor of S pneumo
Antiphagocytic polysaccharide capsule (+ve quellung rxn, capsule swells and appears as halo when anti-capsular Abs and methylene blue dye are added)
What d/o are children w/ conduct d/o at risk for developing as adults?
Antisocial personality d/o. APD cannot be dx before age 18
Adjustment d/o time frame
Anxiety onset is w/in 3 months of stressor onset, and does not persist for >6 mo
Indications for diazepam
Anxiolytic (GAD and panic attacks), sedative-hypnotic (insonmia), anticonvulsant (status epilepticus, first line tx for sz due to etoh w/d), muscle relaxant (stop spasticity of MS, strokes, SC trauma, tetanus)
Schizoaffective vs bipolar w/ psychotic features
Any lifetime hx of >= 2 wks of psychotic sx w/o sign mood disturbance = schizoaffective, even if pt currently has mania
Class IB
Class IB have weakest binding, minimal cum effect over mult cycles, selective for ischemic myocardium (elev RMP delays Na chan transition from inactivated to resting state --> inc IB binding. Good for ischemia-induced ventricular arrhythmias)
Antiarrhythmic agent that causes QRS prolongation w/ no QT prolongation
Class IC antiarrhythmic (QRS is a measure of ventricular depol, QT measures ventricular repol)
Agents that increase Prinzmetal angina
Cocaine, alcohol, triptans, dihydroergotamine
Villous adenoma
High grade dysplasia, large and sessile, velvety or cauliflower-like projections. Villous adenoma produce PGE2 --> inc mucin prod, secretory diarrhea. Excess mucin prod (K rich glycoprot) results in hypoproteinemia and hypoK
Sx of atropine toxicity (gardeners may encounter jimsonweed), also s/e of 1st gen antihistamines
Hot as a hare, dry as a bone, red as a beet, blind as a bat, mad as a hatter, full as a flask, fast as a fiddle (dec vagal tone at SA node)
Aldosterone escape
In 1° hyperaldosteronism, hypernatremia and pedal edema are rarely observed b/c high aldo leads to inc intravasc vol --> inc RBF, inc ANP --> limits net Na retention
Regional wall motion abnormality
Ischemic heart disease (MI)
Acute compartment syndrome 2° to reperfusion injury
Ischemic tissue is flooded w/ O2, and O2 reacts w/ xanthine oxidase, NADPH oxidase, and NOS to form ROS
NAD is a cofactor for which TCA enzymes?
Isocitrate dehydrogenase, a-KG dehydrogenase, malate dehydrogenase. Succinate dehydrogenase uses FAD.
Which TB drug targets the cell wall and prevents +ve acid fast staining?
Isoniazid - inhibits mycolic acid synthesis
Which drug has a bimodal distribution (slow and fast acetylators?
Isoniazid. Slow acetylators also metabolize dapsone, hydralazine, and procainamide slowly. Slow acetylators at inc risk of toxicity, fast acetylators need higher doses
Pathogenesis of Janeway lesions vs Osler nodes
Janeway - microemboli to skin vessels, Osler - immune-complex deposition in skin
Do not resuscitate (DNR) order
Indicates that a patient should not undergo cardiopulm resuscitation, including basic life support (mouth to mouth breathing, chest compressions) and advanced cardiac life support (intubation, mech vent, defib, pressors)
Breast milk jaundice
Indirect hyperbilirubinemia that peaks at age 2 weeks. Inc absorption and increased enterohepatic circulation of bilirubin
MOA of aspirin in preventing MI and stroke
Irreversible acetylation of platelet COX-1, leading to dec formation of TXA2
Landmarks of local anesthesia in labor (too late for epidural)
Landmarks are ischial spines and sacrospinous ligament (inject close to spine). S2-4 roots, innerv perineum and genitals. Pudendal nerve block
What is the most commonly delayed milestone?
Language. At age 2, vocab should be 50-200 words and be able to use 2-word phrases. Do hearing test as well
Orphan Annie nuc
Large cells w/ overlapping nuc containing finely dispersed chromatin, empty or ground glass appearance
ARPKD
Large cysts seen at birth, die during first decade of life from renal failure, hepatic fibrosis, pulm hypoplasia
Risk factor for ovarian torsion
Large ovarian mass (e.g., cyst, neoplasm) causes ovary to twist and occlude the ovarian vessels and nerves in suspensory ligament --> sudden onset unilat pelvic pain, N/V, fever
Cowdry Type A bodies
Large pinkish-purple intranuclear inclusions (not intracytoplasmic). Herpes family also has multinucleated giant cells (+ve Tzanck smear)
Pulsus paradoxus
Large quantity of pericardial fluid prevents expansion of ventricular free walls --> intraventricular septum bulges into LV to allow RV to fill --> dec LV filling vol
PCNSL (1° CNS lymphoma)
Large solitary lesions suggest PCSNL, but multiple lesions may be seen. 90% are DLBCL (B cell origin), EBV identified in virtually all cases. T lymphocytes are malig cells in AIDS-assoc T-cell lymphoma
Defect of GH receptor
Laron dwarfism (dec linear growth, high serum GH concentration, low circ IGF-1)
Two most important factors in osteoclast differentiation
M-CSF and RANK-L, stimulated development of mature, multinuc osteoclasts. RANK-L and RANK interaction is blocked by OPG, which is a decoy receptor
Five receptors in vomiting reflex, which are good for chemo-rel V?
M1 muscarinic, D2 dopaminergic, H1 histaminic, 5-HT3 serotonergic, NK1 neurokinin. 5-HT3 antag (ondansetron), D2 antag (metoclopramide), NK1 antag (prevent substance P release) good for chemo-rel vomiting
Auer rods are seen in which lymphomas?
M2 AML and M3 AML (i.e., APML characterized by t(15:17)). Not seen in M4 (which is characterized by inv(16))
How does muscarine cause somnolence?
M3 receptors on endothelial surface --> activation promotes NO release, which diffuses into vascular SM cells. EVERYWHERE ELSE, M3 causes inc in IC Ca and SM constriction (detrusor bladder muscle contraction, inc intestinal peristalsis, miosis, salivation (exocrine gland secretion)
Selegiline
MAO-I, type B inhibitor. Blocks MPTP from causing Parkinson's by preventing MAO-B from metabolizing MPTP into active MPP+ that causes neuro damage
Growth factor signaling pathways
MAPK, PI3K/Akt/mTOR (mTOR inhibited by PTEN), IP3, cAMP, JAK/STAT. A cancer drug is sirolimus/rapamycin (mTOR inhibitor)
Contralat hemiparesis and hemisensory loss of face and upper limb
MCA stroke
Maintenance dose
MD = Cpss x CL / F. MD = 4 mg/L x 0.5 L/min x 60 min/h x 6 h
Contact precautions
MDR organisms (MRSA, VRE), enteric organisms (C diff), scabies. Soap and water handwashing for C diff, nonsterile gloves, gown, private room preferred, dedicated stethoscope and BP cuff
Branching papillae with cells containing empty-appearing nuclei
Papillary thyroid cancer - papillary structures w/ concentric calcifications are Psammoma bodies, ground-glass/empty nuc are Orphan Annie
Pigmented basal cell carcinoma
Papules, nodules, or plaques w/ rolled borders on sun exposed areas
Kussmaul sign
Paradoxical rise in JVP with inspiration (normally drops), b/c volume-restricted RV cannot accommodate inspiratory inc in VR
Which amino acid is precursor for serotonin syndrome?
Tryptophan
Path of the pudendal n
Ventral rami of S2-4, passes b/n piriformis and coccygeus, exits pelvis thru greater sciatic foramen, reenters pelvis at ischial spines thru lesser sciatic foramen --> sensation to external genitalia, skin around anus/perineum, external urethral and anal sphincters. Susceptible to stretch injury around ischial spine (active pushing during prolonged second stage labor)
High QRS voltage in precordial leads
Ventricular hypertrophy, most commonly due to prolonged untreated HTN
QT interval
Ventricular repolarization (Class III prolong QT interval) --> torsades
Most common manifestation of osteoporosis
Vertebral fractures, and with advanced age there is an inc risk of hip fracture
How do cancers of pelvis spread to lumbosacral spine?
Vertebral venous plexus (VVP), comm w/ many venous networks incl prostatic venous plexus --> goes up to venous supply of brain by valveless sys
How do non-pathogenic strains of C diphtheria acquire pathogenicity?
Phage conversion permitting exotoxin production w/ the Tox gene. Strep pneumo acquires ability to prod capsules via transformation. E coli acquire ability to form pili via bacterial conjugation
Phase I vs Phase II block of depolarizing neuromusc blocking agents
Phase I - continuous depol of endplate resulting in flaccing paralysis. Phase II - despite cont depol, nAChR is desensitized --> similar to non-depol blockade. But, nAChR is nonselective, massive K can leak out of cells
Syndromes due to lung tumor
Phenic nerve irritation and palsy, Horner syndrome, Pancoast tumor (tumor of lung apex), SVC syndrome, hoarseness, dysphagia
Irreversible alpha antagonist: phenoxybenzamine or phentolamine?
Phenoxybenzamine.
Causes of DRESS syndrome (occurs 2-8 wks after drug exposure)
Phenytoin, carbamazapine, allopurinol, sulfasalazine, vanco, minocycline. Sx: fever, generalized lymphadenopathy, facial edema, morbiliform skin rash
Gingival hyperplasia
Phenytoin, due to inc expression of PDGF. Other s/e of phenytoin are ataxia, nystagmus, coarse facial features, hirsutism, megaloblastic anemia, CYP450 inducer
Med to dec risk of bone fractures and breast cancer in pt w/ +ve fhx of breast cancer
Raloxifene - unlike tamoxifen, this med is a SERM that has estrogen agonist activity on bones and estrogen antag effect on uterus (no inc risk of endometrial cancer)
Important sequences to know
Poly-A tail ~ AAAUAAA, telomere ~ TTAGGG (Telomerase TAGs for Greatness and Glory), splice sites ~ GU (5') and AG (3'), 5' cap ~ 7-methylG, tRNA AA site ~ CCA (3'), T loop of tRNA ~ TUC
ACL injury
Valgus stress to knee
Most common injury that causes MCL tear
Valgus stress. Meniscal injury is diagnosed by joint line tenderness on knee flexion
Most common cause of aortic stenosis
Valvular calcification (developed world) or rheumatic heart dz (developing world)
How to differentiate effect modification and confounding?
When the groups are stratified, apparent differences due to confounding in overall analysis disappear. In effect modification, differences in outcome appear with stratification.
Arterial puncture above the inguinal ligament
Retroperitoneal hemorrhage (vessel lies inferior to peritoneum). Bleeding in retroperitoneal space cannot be controlled w/ external compression --> life threatening hemorrhage, hypotension, ipsi flank pain
SAD PUCKER
Retroperitoneal organs. Tail of panc is peritoneal
HDN
Rh incompatibility, neonates p/w jaundice on first day of life due to Ab-med hemolysis, indirect hyperbilirubinemia, and +ve direct Coombs
Migratory polyarthritis
Rheumatic fever (JONES)
When are S3 and S4 heard?
S3 is low-frequency sound after S2, S4 is before S1
Complete (third-degree) AV block
SA node impulses cause atrial contraction, and AV node impulses cause ventricular contraction
Inferiormost border of spinal cord vs dural sac
SC ends at L1 in adults (L2/3 in infants), dura ends at S2
Fall on outstretched hand, point tenderness b/n EPL and EPB
SCAPHOID FRACTURE --> AVASCULAR NECROSIS AND NONUNION (dorsal scaphoid branch of radial a supplies majority of scaphoid)
Pancoast tumor
SCC, adenocarcioma (NSCLC) near sup sulcus causing Horner's
Macrocytic anemia in a sickle cell dz pt
SCD leads to inc erythrocyte turnover --> inc folic acid requirements. Additionally, extramedullary erythropoiesis common in SCD (body compensating for reduced # of RBCs) --> reticulocytosis inc MCV artificially
Thymic aplasia is seen in which diseases?
SCID and DiGeorge syndrome
Antioxidant enzymes
SDM, glutathione peroxidase, catalase. In post-ischemic state, prod of ROS exceeds antioxidant capacity --> inc cell injury and death
Treatment of acute MI
SELECTIVE BETA-BLOCKER (METOPROLOL, atenolol, bisoprolol, nebivolol) - REDUCE HR, CO, and MVO2. Can also use combined beta and alpha receptor blocker (carvedilol, labetalol). Do not use nonselective beta-blockers (nadolol, propranolol) as they trigger bronchospasm in COPD/asthma pt
Most serious s/e of lamotrigine
SJS (<10% of body surface) or TEN (>30% of body surface). Look out for skin rash! Drugs assoc w/ SJS/TEN are lamotrigine, carbamazepine, phenobarbital, phenytoin
Extrapulm manifestations of Mycoplasma pneumoniae
SJS, jt pain, encephalitis, cardiac rhythm disturbances, bullous myringitis
Excess leves of B cell activating factor (BAFF)
SLE, autoimmune dz
Which organ is supplied by celiac a and is not foregut derivative?
SPLEEN (most common intraabd organ injured during blunt trauma. Derived from mesoderm of dorsal mesentery)
Pt started on SSRI and has inc agitation/anxiety
SSRI takes 4 weeks to work, and may cause inc agitation/anxiety at first. Prescribe short or intermediate acting benzo to reduce anxiety/insomnia
Cavernous hemangioma (can cause neuro deficits and sz)
Vascular malformations involving deeper tissues of body (liver and brain). Mulberry like appearance, purple clusters. Abnormal dilated BVs with a thin adventitia --> intracerebral hemorrhage
Conditions assoc w/ fibrinoid necrosis
Vasculitis (PAN), malignant HTN, DM
Ewing sarcoma
Single lesion, months of pain and swelling, onion peel appearance, multiple layers of periosteal rxn. Arises in diaphysis of long bones
Manifestations of hyperestrinism in cirrhosis pt
Spider angiomata (dilation is due to estrogen, and pregnant women often get spider angiomas), testicular atrophy, dec body hair, gynecomastia. # and size of angiomata correlate to severity
Drugs absolutely contraindicated in HOCM
Vasodilators (DHP CCB, nitroglycerin, ACE-I), and diuretics
Libman-Sachs endocarditis
Vegetations composed of sterile platelet thrombi intertwined w/ strands of fibrin, immune complexes, and mononuc cells
Muscles involved in arm abduction
Supraspinatus (first 15°), deltoid up to horizontal, serratus ant and trapezius for complete abduction of arm over head
21F w/ wt loss, despite normal food intake, polyuria, polydipsia
T1DM. Get fasting blood glucose or HbA1c measurement. Osmotic sx (polyuria, polydipsia, blurred vision) suggest blood glu > 180 mg/dL
Alirocumab
mAb against PCSK9 that inhibits the degradation of LDL-R --> inc availability of LDL-R on hepatocyte membranes
NF1
von Recklinghausen dz, NF1 TSG mutation (encodes protein neurofibromin), chrom 17, sx: café au lait spots, multiple neurofibromas, Lisch nodules
Why is PT normal in heparin use
Addition of heparin neutralizers in the PT reagant
Most deoxygenated blood in body
Coronary sinus (direct drainage of cardiac venous blood - myocardial O2 extraction is high)
Pseudohypoparathyroidism or CKD labs
Elev PTH, low Ca, elev PO4. CKD results in dec prod of 1,25-OH2 Vit D
Precipitating factors of AIP
1) Inherited PBG deaminase def, or 2) ALAS induction (phenobarbital, griseofulvin, phenytoin, etoh use, smoking, low-calorie diet)
Sx of hematocolpos
1° amenorrhea, normal 2° sexual characteristics, cyclic abd/pelvic pain --> pressure causes back pain and pain w/ defecation, vaginal bulge and mass palpated ant to rectum
Absence sz frequency
3 Hz
Oppositional defiant d/o
Argues w/ adults, defies authority figures, refuses to follow rules, blames others for own mistakes or misbehaviour
Path of gonadal a
Arise from abd aorta, courses obliquely downward near psoas major, cross ant over ureter, parallel to ext iliac vessels
Enterocytes contain clear/foamy cytoplasm, esp at tips of villi
Accum of lipids in absorptive cells of intestinal epith --> abetalipoproteinemia (impaired formation of apoB). Apo B100 in VLDL, Apo B48 in chylomicrons
Fruity breath
Acetone
Intranuc acidophilic vs basophilic inclusion
Acidophilic ~ herpes (Cowdry), basophilic ~ CMV (owl eye)
Which arteries are affected by saccular aneurysms?
Ant and post communicating arteries
Derivatives of surface ectoderm
Ant pit (Rathke pouch), lens and cornea, olfactory epith, salivary glands, epidermis
Most common site of acute compartment syndrome
Anterior compartment of leg (contains foot extensors, ant tibial artery, deep peroneal nerve)
What is the most common site of MRSA colonization in HCW?
Anterior nares (25-30% of people)
Ranolazine
Antianginal agent, blocks Na and K channels, dose-dep QT interval inc, no TdP
cGMP
BAD GraMPa (BNP, ANP, EDRF (NO)
Preferred tx for a-fib w/ rapid ventricular response
BB and CCB. Second-line is digoxin for pts w/ systolic cardiac dysfcn
Bloom syndrome
BLM mut, defective DNA helicase. Chrom instability, growth retardation, facial anomalies (microcephaly), photosensitive rash, immunodef
Hypogammaglobulinemia
Bacterial infections
Bacteroides fragilis and appendicitis
Bacteroides expresses unique surface polysaccharides that favor abscess formation
Damage to cerebellar vermis
Balance and coord of axial/prox limb muscles --> gait and trucal ataxia, nystagmus, vertigo
Septic shock and elev AG
End-organ hypoperfusion --> impairs tissue oxygenation, dec ox phos --> shunting to lactic acidosis
Which embryologic tissue are thyroid follicular cells derived from?
Endoderm
Sodium nitroprusside
Balanced arterial and venous vasodilator. Generates NO while in bloodstream and not in vasc SMCs like other nitrates, less selective for large veins. Good for hypertensive emergency b/c it acts on large arteries and veins
Frequent complication of Wilson's dz
Basal ganglia atrophy (i.e., hepatolenticular degeneration)
DNA glycosylase
Base excision repair, removes nitrogen base from sugar phosphate backbone
Where should thoracocentesis be performed?
B/n inf margin of lung and parietal pleura (6-8-10, 8-10-12 in ant, lat, and post positions). Thus, b/n rib 6-8 along MCL, 8-10 in midax, 10-12 in paravertebral
Sx of adult lead poisoning
Bluish pigmentation at gum-tooth line (lead line), wrist drop
Osteoporosis
Bone density that is 2.5 or more st dev below the mean for peak young adult bone density
Treatment for hypocalcemia after thyroidectomy
Calcium and calcitriol supplementation
Which stones occur in increased pH?
Calcium phosphate, ammonium magnesium phosphate
C1 esterase inhibitor deficiency
C1 esterase inhibitor normally suppresses activation of C1 and inactivates kallikrein (kininogen --> bradykinin). Sx: inc active kallikrein and bradykinin, low C4 (substrate for C1 esterase)
Ansa cervicalis
C1-C3, courses deep to SCM, loops around IJV, branches innervate sternohyoid, sternothyroid, omohyoid
Osteonecrosis (avasc necrosis)
Causes: thrombotic/embolic occlusion (sickle cell, fat emboli, decompression sickness), vasculitis (SLE), glucocorticoids, vasc inflam, etoh abuse, trauma. Sx: pain on wt bearing, dec ROM, no swelling/warmth/erythema around. Gross inspection: wedge-shaped zone of necrosis, articular cartilage is viable but detached from underlying bone. Microscopic: dead bony trabeculae w/ empty lacunae, necrosis of surrounding adipocytes
Diverticulosis
Commonly infections sigmoid colon, individuals age > 60, most pts are asxatic
Complications of failure of obliteration of processus vaginalis
Communicating hydrocele and indirect inguinal hernia
Most common heart defects in Down syndrome
Complete AV canal, ASD, VSD
Parainfluenza
Croup (laryngotracheobronchitis). P/w "barky", seal-like cough and inspiratory stridor
Glycosyltransferase
Crucial component of peptidoglycan synthesis. Peptidoglycan found in Gram+ and Gram-, not in Mycoplasma
Which compound is absorbed from intestine indep of panc fcn?
D-xylose (used to test for brush border absorptive fcn). Panc has sig secretory reserve, up to 90% must be destroyed before clinically evident malabsorption. Panc enzymes needed for polysaccharides, monosaccharides don't need panc enzymes
21-hydroxylase deficiency lab findings
Dec cortisol, dec aldosterone, inc serum ACTH, inc 17-hydroxyprogesterone. Blocked enzyme prevents syn of cortisol and aldo, shunted to inc androgen prod --> low cortisol feeds back to inc ACTH prod
Things that exacerbate HCM murmur
Dec preload (Valsava, supine to standing, nitroglycerin administration)
Why do pts w/ normal pres hydrocephalus get urinary incontinence
Dec absorption of CSF --> ventricular enlargement, traction on cortical efferent/afferent fibers --> disrupts periventricular pathways
Motor innervation of tongue
Hypoglossal, except palatoglossus (vagus n)
Which CCBs affect only arterial SM and not heart?
DHP (nifedipine, amlodipine, felodipine - cause reflex tachycardia in response to peripheral vasodil). Non-DHP (verapamil acts at heart only, diltiazem acts at heart and BVs)
DIC vs TTP-HUS
DIC: Pts bleed, coag cascade is activated, PT and PTT are prolonged, low fibrinogen, inc D-dimer/FDP (fibrin deg prod). TTP-HUS: no bleeding, only platelets activated, normal PT/PTT, normal fibrinogen
Interplay b/n K and DKA
DKA results in metabolic acidosis, H+ goes into cells and K comes out. K also lost in urine --> high serum K, but low TBK in DKA. Upon tx, insulin drives K back into cells (glucose into cells drags K w/ it), causing hypokalemia --> must administer K w/ insulin!
Alcohol w/d, fluctuating arousal levels
Delirium tremens
Which enzymes does lead poisoning inhibit?
Delta-aminoevulinate dehydratase and ferrochelatase
Stages of grief
Denial, anger, bargaining, depression, acceptance
What determines the ventricular response in a-fib?
Depends on transmission of abnormal atrial impulses thru AV node. Each time the AV node is excited, it becomes refractory and most atrial impulses never reach the ventricles
S/e of succinylcholine
Depolarizing neuromusc blocking agent (skel muscle relaxant). Malignant hyperthermia (esp w/ halothane), hyperK in pts w/ burns, crush injuries etc., and bradycardia
Amyloid angiopathy of AD
Deposition of Abeta deposits in the media/adventitia of cerebral vessels --> vessel weakening, intracranial hemorrhage
Calcific tendonitis
Deposition of calcium hydroxyapatite crystals in periarticular soft tissues, rotator cuff tendons most commonly affected
Anergy to cutaneously applied Candida infection
Depressed cell-mediated immunity, b/c everyone should be sensitized to Candida
What does base excision repair correct?
Depurination, alkylation, oxidation, deamination, excessive consumption of dietary nitrites
Function of E6 and E7 in HPV
E6 - p53, E7 - Rb
Which virus is known for its ability to "immortalize" B cells?
EBV (typically causes a latent infection of B cells)
CYSTOSCOPY
ENTEROCOCCUS
Organisms that have similar toxins
ETEC (traveller's diarrhea) ~ cholera toxin (inc cAMP), diphtheria ~ Pseudomonas (ribosyl of EF-2), EHEC ~ Shigella (inhibit 60S), anthrax ~ pertussis (EF, inc cAMP)
Contaminated water consumption
ETEC, Campy, Salmonella, Shigella, Giardia
Berry/saccular aneurysms are assoc w/?
Ehlers-Danlos syndrome and ADPKD
Deficiency of B6, B9, or B12
Hyperhomocysteinemia - prothrombotic state
Neuritic plaques
I.e., senile plaques - extracell deposits often found in medial temporal lobe (hippocampus, amygdala, entorhinal cortex). Central a-beta core surrounded by dystrophic neurites
Presentation of blastomycosis
In half of immunocompetent adults, presents as lung infection or flulike illness (F, chills, myalgia, HA), pneumonia. Immunocompromised: disseminated (fever, wt loss), skin lesions, bone pain (osteolytic)
Cortisol receptors
In inactive state, found in cytoplasm in assoc w/ heat shock prots. Binding of cortisol causes release of HSP, dimerization of receptor, and transloc into nuc
Apple peel deformity
In intestinal atresia, a distal segment of ileum assumes a spiral configuration around an ileocolic vessel
Regulation of phosphorylase kinase in liver vs muscle
In liver, PK activated by epi and glucagon binding to Gs prot coupled receptors and inc cAMP. In skel muscle, inc IC Ca is powerful activator of muscle PK
Damage to what BV causes AVN of femoral head?
Medial circumflex a
Near miss
Medical error that has been recognized before any harm has been done to the pt
Falling asleep at inappropriate times, auditory hallucinations
Narcolepsy due to low levels of orexin - tx is modafinil
Segmented viruses
Orthomyxo, bunya, arena, reo
Location of Zollinger-Ellison ulcers vs H pylori/NSAIDs
Proximal duod ulcers - H pylori/NSAIDs, beyond the duod bulb - ZES. ZES ulcers appear in unusual areas (i.e., jejunum). ZES has +ve secretin stim test (gastrin levels are inc by administration of secretin)
Complications of acute pancreatitis (maturation of pseudocyst takes 4-6 wks)
Pseudocyst (lined by granulation tissue, not epith. True cyst has walls lined by epith cells), abscess, necrosis, hemorrhage, infection, organ failure (ARDS, shock, renal failure), hypoCa (precip of Ca soaps)
Synthetic prostacyclin is used for?
Pulm HTN, PVD, Raynaud's
Restrictive vs obstructive lung dz and work of breathing (minute vent = RR x TV). OBSTRUCTIVE ~ INC AIR FLOW RESIST ~ SLOW, DEEP BREATHS ~ HIGH LUNG VOL. RESTRICTIVE ~ INC ER_LUNG ~ RAPID, SHALLOW BREATHS ~ LOW LUNG VOL.
Restrictive (IPF, pulm edema, ARDS) - work of breathing min at high RR --> rapid, shallow breaths. Breathe at low lung vol (low TV) --> to maintain minute vent, high RR. Obstructive (asthma, COPD, fixed upper aw obstruction - goiter) - work of breathing min at low RR --> slow, deep breaths. Breathe at high lung vol (high TV) --> to maintain minute vent, low RR.
Mixed cryoglobulinemia
Small to medium vessel vasculitis, circulating Ig-complement complexes that precipitate on refrigeration. Assoc w/ SLE, Hep C. Sx: fatigue, arthralgias, LE palpable purpura, renal dz from IgM deposition in glom
Neurovascular triad of thyroid
Superior thyroid a, sup thyroid v, external branch of sup laryngeal n. External branch at risk during thyroidectomy --> cricothyroid m paralysis
Mononeuritis multiplex is associated w/ which dz?
Wegener's, polyarteritis nodosa
Placental abnormalities and FGR
Tobacco use --> dec estriol levels
Single most preventable cause of death in US
Tobacco use and smoking. Smoking inc risk of macrovasc (MI, stroke) and microvasc (retinopathy, nephropathy) complications of DM
Oxygen-induced hypercapnia
V/Q mismatch. Providing high concentration O2 reverses pulmonary vasoconstriction at poorly-ventilated alveoli --> inc in physiologic dead space, reduced total alveolar vent
Gingivostomatitis (primary infection only) vs herpes labialis (reactivation of HSV, mild, unilat, limited to lips)
Vesicles on lips and hard palate, fever, lymphadenopathy. Pain causes dehydration --> hospitalization. 3M's of herpes seen on Tzanck smear: multinuc, margination, nuc molding
What risk remains in few mos after vasectomy
Viable sperm in distal vas up to 3 mo after vasectomy, and at least 20 ejaculations
Ingestion of undercooked shellfish
Vibrio, Norwalk virus, Hepatitis A
Microglial nodules and multinuc giant cells
Viral infections of CNS (phagocytizing virally infected neuron). Found in HIV-assoc encephalopathy
Which vitamins are missing from exclusive breastfeeding?
Vitamin D and K
How does phenylephrine cause dec HR?
a1 agonism causes vasoconstriction --> inc BP elicits baroreceptor-mediated inc in vagal tone --> dec SV and dec HR
What must a pt exposed to Hep B have in addition to anti-HBsAg?
anti-HbC
Most common CF mechanism of bad CFTR
dF508 mut --> abnormal post-translational processing (failure of glycosylation) --> prot targeted for proteasomal deg
Berkson's bias
selection bias created by choosing hospitalized pts as control group
Desmopressin is used to treat what dz?
vWD and Hemophilia A
Which part of tubular sys contains most dilute urine in pt w/ high ADH?
Distal tubule
Live attenuated vaccines
Polio, MMR, rotavirus, influenza, yellow fever, VZV
Leukocytes and pear shaped organisms
Trichomonas vaginitis
Dihydrouridine, pseudouridine, ribothymidine
T-psi (uracil)-C ~ T-arm for binding to ribosome. 3' end is CCA
Systemic mastocytosis
Clonal mast cell prolif in BM, skin and other organs, assoc w/ KIT mut (CD117), predisposes to gastric hypersecretion
Location of femoral hernias
Protrude thru femoral ring, lat to pubic tubercle, medial to femoral a and v. More common in women, more common on R
Secondary hemochromatosis
Pts w/ beta-thal and severe thal have chronic hemolytic anemia --> iron overload from repeated blood transfusions
Question to ask pts to assess language proficiency
"How well do you speak English: not at all, not well, well, or very well?" If pt cannot respond or "not well", find an interpreter
CXR findings of asbestosis
"Ivory white", calcified, supradiaphragmatic and pleural plaques, LOWER ZONES. 20-30 yr latency b/n asbestos exposure and onset of sx (prog diffuse pulm fibrosis). Ferruginous bodies
Paget disease of bone
"Mosaic architecture", normal serum Ca and PO4
Salmonella osteomyelitis in SCD
"Vi antigen" - special capsule (Vi for virulence) that protects it from opsonization and phagocytosis. Main virulence factor of Staph aureus in osteomyelitis is adhesion to Col
Pathophysiology and tx of emesis
1) Gastrointestinal irritation (infections, chemo, distension) result in inc mucosal serotonin release --> activation of 5-HT3-R on vagal and spinal aff nerves, go to medullary vomiting center. Tx: 5-HT3-R antag (ondansetron). 2) Dopamine involved in central nausea (acute migraines). Tx: dopamine receptor antag (metoclopramide). 3) First-gen H1-R antag and mAChR antag used to treat vestibular nausea.
Mechanisms of resistance to penicillins
1) Beta-lactamases (cephalosporins, carbapenems etc. are unaffected), and 2) modification of PBPs (all beta-lactams are affected, found in MRSA)
Mechanisms of resistance to isoniazid by M tb
1) Dec in bacterial expression of catalase-peroxidase enzyme required for isoniazid activation, and 2) modification of protein target binding site for INH
Progression of CIS to invasive tumor
1) Detachment from surrounding cells by dec expression of mols incl E-cadherins, 2) adhere to BM by inc expression of laminin, 3) invade BM by upreg MMP, cathepsin D protease
Tx of cyanide toxicity
1) Direct binding of cyanide ions (hydroxocobalamin), 2) induction of methemoglobinemia (sodium nitrite), and 3) use of detoxifying sulfur donors (sodium thiosulfate)
How does HFE mut inc iron accum in body?
1) Enterocytes inc apical expression of divalent metal transporter 1 (DMT1) --> inc iron absorption from intestinal lumen, 2) hepatocytes dec hepcidin syn --> inc ferroportin on enterocytes --> inc iron secretion into circ
Five types of xanthomas
1) Eruptive xanthomas ~ TGs/chylomicron excess, 2) tuberous/tendinous xanthomas ~ cholesterol excess, plane xanthomas ~ PBC, xanthelasma
Clearance of particles from lungs
1) Largest particles in upper aws (nasal passages, pharynx) cleared by coughing and sneezing. 2) Medium particles up to terminal bronchioles cleared by mucociliary elevator. 3) Small particles (<2 um) in resp bronchioles and alveoli are phagocytized by Mos. W/ excessive particulate load (pneumoconiosis), Mos release cytokines and induce pulm fibrosis
Three mechanisms of Down syndrome inheritance
1) Meiotic nondisjcn (~95%) - maternal origin, 2) unbalanced Robertsonian transloc (2-3%) - extra genetic mat'l attached to one of their chrom, INHERITED FROM UNAFFECED PARENT, 3) mosaicism (<2%) - nondisjcn during mitosis --> two diff cells lines (one normal, one Down). Severity depends on %age of cells from Down lineage in pt
MOA of morphine
1) Opiates bind to mu receptors on presynaptic terminal and block VGCC --> dec Ca influx and NT release, and 2) bind to mu receptors on postsynaptic membrane and open K chan --> membrane hyperpol
Asbestosis (inhalation of fine fibers cuases epith cell injury, activation of Mo, chronic interstitial inflam and fibrosis)
1) Pleural plaques of lower lungs (dense Col that becomes calcified), 2) progressive, difuse pulm fibrosis, asbestos bodies (golden-brown rods w/ translucent centers), 3) bronchogenic carcinoma (synergistic w/ smoking) > malig mesothelioma (more specific for asbestos exposure)
Two sources of alkaline secretions to neutralize gastric HCl
1) Submucosal (Brunner) glands secrete alkaline mucus into duod, and 2) epith cells of pancreatic ductules prod watery secretions w/ bicarb
Mechanism of vitiligo vs albinism
Former - autoimmune destruction of melanocytes, latter - normal melanocyte # w/ dec melanin prod (due to dec tyrosinase activity)
GABA_A vs GABA_B
GABA_A are ligand-gated Cl channels (benzos, barbiturates, GABA), whereas GABA_B use G proteins (baclofen acts on GABA_B)
Parts of duodenum
1st - not retroperitoneal, 2nd - close to head of pancreas, contains ampulla of Vater, 3rd - close to uncinate process of panc and SMA/SMV, 4th - becomes jejunum past lig of Treitz
Causes of membranous glomerulopathy
1° (anti-PLA2-R) or 2° to drugs (NSAIDs, penicillamine, gold), infections (HBV, HCV, syphilis), SLE, solid tumors
What form is CO2 carried in the RBC? What is the chloride shift?
15% - carbamate bound to Hb, 85% - bicarbonate ion floating in the RBC. Bicarb can float out of RBC, Cl- comes in to maintain electroneutrality
Ghon focus, Ghon complex, Ranke complex
1st - focal lesion in mid-to-lower lungs. 2nd - lower lobe lesion + ipsilat hilar lymphadenopathy. 3rd - healed Ghon complex causing benign, calcified complex.
How to distinguish b/n 1° and reactivation TB?
1° TB always deposits organisms in lower lungs (Ghon focus, later spread to Ghon complex) Reactivation TB establishes in upper lungs (apex) due to dec lympatic flow and inc O2 tension --> cavitation, erosion into pulm vessels (hemoptysis) or hematogenous dissemination (miliary or extrapulm TB)
Meckel's Rule of 2
2% of pop, 2 feet from ileocecal valve, 2 inches in length, 2% are sxatic, males are 2x as likely to be affected
Mechanism of 2,3-BPG
2,3-BPG binds 2 beta globin chains and stabilizes T deoxyhemoglobin --> promotes oxygen unloading
Most common causes of neonatal meningitis (0-3 mo)
GBS, E coli, Listeria
How long can the heart endure complete arterial ischemia?
20-30 min w/o severe consequences. Brief periods cause myocardial stunning, not necrosis
CATCH-22 (DiGeorge)
22q11: Cleft palate, abnormal facies, thymic aplasia --> T-cell deficiency, cardiac defects, hypocalcemia 2° to parathyroid aplasia
Two types of pneumococcal vaccines
23-valent polysaccharide vaccine (PPSV23) protects against wider range of serotypes, but Ab levels decline over 5 yrs. Not immunogenic in age<2 b/c of their immature humoral Ab response. Prevnar - 13-valent conjugated to nontoxic diphtheria protein, strongly immunogenic in infancy
How long does renal compensation for met alk take?
24-48 h
Adenosine deaminase def
2nd most common cause of SCID (after X-linked SCID). Adenosine accum toxic to lymphocytes. Tx: BMT
Skin finding of syphilis
2° syphilis ~ condyloma lata, 3° syphilis ~ gummas (painless, indurated granulomatous lesions that progress to white-grey rubbery lesions that ulcerate, cutaneous)
Optic glioma
Glioma that affects optic n, assoc w/ NF1, consist of immature astrocytes w/ microcystic degen and Rosenthal fibers
Patient with both nicotinic (dry mouth) and muscarinic blockade (diplopia, dysphagia)
3 D's (diplopia, dysphagia, dysphonia) = Food poisoning by C botulinum (inhibits ACh release from presyn nerve terminals at NMJ). Repetitive stim inc [Ca] and mobilizes add'l ACH vesicles.
HAART for pregnant women
3 drugs from 2 classes (2 NNRTIs + PI/NNRTI/II). Avoid efavirenz (teratogenic)
Biventricular pacemaker
3 leads: first 2 placed in RA and RV, third lead used to pace RV (lies in atrioventricular groove).
Function of 30S vs 50S
30S - binds mRNA and tRNA; 50S - peptidyltransferase (catalyzes peptide bond formation b/n AAs). Initial N-formylmethionine-tRNA binds to P site
Difference b/n 3° and 4° amines in reversing atropine toxicity
3° (physo, donepezil, rivastigmine) are lipophilic and easily cross BBB, reversing central and peripheral sx. 4° (neostigmine, pyridostigmine) are hydrophilic, reverse peripheral sx only
How long after MI are myocardial changes visible?
4 h
How long does it take for drug to reach 95% steady state []?
4-5 half lives. 1 half life = 50%, 2 half lives = 75%, etc.
Most common karoytype of complete mole
46,XX (one paternal germ cell fertilizes empty egg and duplicates), or two sperm invade empty egg. 46,XY less common
ADPKD
50% of adults progress to ESRD by age 70, affects renal fcn at age 30-40, HTN, abd and flank pain, gross hematuria, UTI, kidney stones. Extrarenal manifestations are liver cysts and intracranial aneurysms
Which is the only rRNA not formed by RNA pol I?
5S rRNA, formed by RNA pol III
Cri du chat
5p- deletion: round face, catlike cry, microcephaly, epicanthal folds
At what platelet count does spont bleeding occur?
<10000/uL
Time that myocardium can reversibly recover from ischemia
<= 30 minutes. Myocardial stunning - on restoration of blood flow, full myocardial function does not return for hrs to days (gradual)
Chronic graft rejection
>3 mo - years post-transplant. Worsening hypertension, prog rise in serum Cr --> obliterative fibrous intimal thickening, scattered mononuc infiltration. Shrinking of renal parenchyma (ischemic injury), tubular atrophy and interstitial fibrosis
At what percentage does a coronary plaque cause stable angina?
>75%. Below that is asymptomatic. Ulceration with partially obstructed thrombus leads to unstable angina
Presentation of HAV in children age <6
>80% have silent or subclinical (anicteric) infection
How long do sx have to occur to dx PTSD?
>= 1 mo. ACUTE STRESS D/O IS SAME SX BUT FOR 3d-1mo after exposure
Persistent depressive d/o
>= 2 yrs of sx, >= 2 depressive sx
Delusional disorder
>=1 delusion for >= 1 month, no other +ve sx and mild functional impairment. One specific theme: grandiose, erotomanic etc.
Full mutation of FMR1 in Fragile X?
>=200 trinuc repeats (nml 55) leads to DNA hypermethylation
Which antibodies from GAS attack the heart in rheumatic fever?
M protein and N-acetyl-beta-D-glucosamine attack myosin. Rheumatic fever - JONES. Aschoff bodies seen in carditis
Postpartum depression
Prevalence 8-15%, onset w/in 4-6 wks up to 1 yr, >=2 weeks of moderate to severe depression (SIGECAPS), management: antidepressants, psychotherapy
Medications proven to improve survival in HFrEF
ACE-I (captopril, enalapril etc.), ARB (valsartan, losartan etc.), beta-blocker (bisoprolol, carvedilol, metoprolol), MRA (epleronone, spironolactone), hydralazine and nitrates
Where do ACL and PCL attach?
ACL - anterior portion of intercondylar tibia to posterior medial side of lateral femoral condyle; PCL - posterior part of intercondylar tibia to anterolat surface of medial femoral condyle
AD vs AR inheritance
AD - structural (defective noncatalytic prots), AR - enzyme deficiency (e.g., classic galactosemia)
Huntington dz (CAG - loss of caudate, ACh and GABA)
AD, age 30-40, insidious onset of personality changes followed by physical sx (aggressiveness, flat affect, depression or anxiety, purposeless choreiform movements of extremities)
Eosinophils kill parasites by what mechanism?
ADCC (proliferation stimulated by IL-5 from Th2 and mast cells) --> eo is coated by IgG and IgE Abs --> eo degranulation. Also do late-stage Type I hypersensitivity and release PG/LT
Two mechanisms of hyperglycemia-induced tissue damage
AGE (nonenzymatic attachment of glucose to proteins and lipids) and polyol overactivity pathway (inc sorbitol inc osmotic pressure of tissue --> water influx, and aldose reductase consumes NADPH --> oxidative stress from depletion of NADPH)
Ipsi loss of pain/temp in face, ipsi facial weakness, contra loss of pain in trunk and extremities
AICA occlusion. "Facial droop means AICA's pooped"
S/e of thiazides
AKI, electrolyte disturbances (hypoNa, hypoK), hyperuricemia and gout, hyperglycemia, hyperlipidemia. Chlorthalidone most potent, but also most metabolic s/e
Hemin infusion in pt w/ AIP downregulates which enzyme?
ALAS
Tx of AIP (port colored urine, acute neuro sx, vomiting, abd pain)
ALAS upreg by CYP450 inducers, downreg by heme and glucose --> give IV dextrose! IV dextrose inhibits PPAR-g, a TF that induces syn of ALAS
What is the most common pediatric malignancy?
ALL. Fever, fatigue, pallor, petechiae, bleeding. B cell ALL for 70-80% of ALL, T cell ALL for 15-17%. T cell ALL more likely to p/w a large ant mediastinal mass that causes SVC syndrome and dysphagia
Gardos (Ca-dep K chan)
Preventing intracellular dehydration. Gardos K chan regulates transport of K and water through RBC memb - blocking reduces efflux
Migraine tx
Abortive therapy for acute migraines: triptans (s/e are BP elev and cardiac events, CI in pts w/ CAD or CVD), proph: beta-blockers, antidepressants, valproate/topiramate
Primary ciliary dyskinesia vs CF
Both have chronic sinopulm infections, nasal polyps, bronchiectasis, digital clubbing. Karteneger - situs inversus, immotile spermatozoa, normal growth. CF: CVABD, panc insuff, failure to thrive
I cell disease
AR, lysosomal storage d/o. Defect in phosphotransferase enzyme --> no post-translational mannose residue addition --> EC secretion of these prots. Coarse facial features, corneal clouding
Friedrich ataxia
AR, mutation of frataxin (FXN) gene. Essential mito prot in assembly of iron-sulfur enzymes. Gait ataxia, loss of position and vibration sense, kyphoscoliosis and foot abnormalities (pes cavus), HOCM and CHF, DM
Mechanism of Zenker diverticulum formation
Abnormal spasm or diminished relaxation of cricopharyngeal muscles during swallowing.
What causes isolated systolic HTN (e.g., 170/80)
Age-related stiffness and dec in compliance of aorta and large arteries
Which muts are assoc w/ late-onset AD?
APO-E4
What protein causes early-onset AD in Down's pts?
APP. Located on chromosome 21 --> extra copy thought to accelerate amyloid accum
Wilson disease
AR, ATP7B mut --> hepatic copper accum, leak from damaged hepatocytes --> deposits in tissues (basal ganglia, cornea). Sx: hepatic (acute liver failure, chronic hepatitis), neuro (Parkinsonism, gait disturbance), psych (depression, personality changes, psychosis). Dx: dec ceruloplasmin, inc urinary copper excretion, Kayser-Fleischer rings
Pathogenesis of hemochromatosis
AR, C282Y mut > H63D on HFE gene (chrom 6). HFE protein is iron sensor normally bound to basolat surface of hepatocytes and enterocytes, interacts w/ transferrin receptor. Abnormal iron sensing --> inc intestinal absorption (inc ferritin, inc iron, dec TIBC, inc TSat)
Presentation of pyruvate kinase deficiency
AR, chronic hemolytic anemia, pallor, scleral icterus, splenomegaly
Alkaptonuria
AR, d/o of tyrosine metabolism. Homogentisate acid dioxygenase def, cannot convert tyrosine --> fumarate. Sx: black urine, blackened tissues
Pancreatitis complicated by hypoxic resp failure w/ bilat pulm infiltrates
ARDS. RFs incl sepsis, pneumonia, trauma, pancreatitis. Pathophys: cytokine release, endoth activation, hyaline membranes. Sx: hypoxia, bilat pulm infiltrates, NORMAL PCWP
Attributable risk percent in the exposed
ARP_exposed = 100 x [(risk in exposed - risk in unexposed)/risk in exposed] = 100 x [(RR - 1)/RR]
Restricted motion of the aortic valve cusps (scarring/thickening)
AS and/or AR, assoc w/ high frequency aortic ejection click
Failed fusion of sup/inf endocardial cushions? What is Eisenmenger?
ASD and/or VSD with L to right shunting of blood. Over time, inc R sided flow leads to pulm HTN --> reversal of flow thru shunt --> cyanosis (goes from L to R shunt to R to L shunt).
Treacher-Collins syndrome
Abnormal development of 1st and 2nd pharyngeal arches --> craniofacial abnormalities result in aw compromise and feeding difficulties, abnormal ossicles --> conductive hearing loss
Embryologic pathophys of ToF
Abnormal neural crest migration leads to ant and cephalad deviation of infundibular septum --> SVD and overriding aorta
Annular pancreas
Abnormal rotation of ventral pancreatic bud forms a ring of pancreatic tissue --> encircles 2nd part of duod, may cause duod narrowing. Sx: asxatic (majority), acute/chronic pancreatitis, obstruction
Above vs below the arcuate line
Above, rectus abdominis surrounded by ant and post sheaths; below, covered only by ant sheath. Horiz transection of rectus abdominis can damage inf epigastric a
Presentation of pneumococcal pneumonia in nonelderly
Abrupt onset fevers, rigors, tachypnea, prod cough, consolidation
Atrial fibrillation
Absence of P waves, irregularly irregular rhythm, varying R-R intervals. Occasionally seen after etoh consumption ("holiday heart" syndrome)
Cutoff for 1° amenorrhea is at what age?
Absence of menses by age 15 for pt w/ normal 2° sex characteristics, or age 13 in girls w/o 2° sex characteristics
Why do anovulatory cycles cause spotting and irreg bleeding?
Absence of ovulation means no corpus luteum and no prog prod. Unopposed estrogen --> endometrium continues to grow, outgrows blood supply --> irregular periods of sloughing. Same phenomenon as ovulatory cycles dec peri-menopausally
Destruction of kinesins causes which histologic abnormality?
Absence of secretory vesicles in nerve terminals
A-fib
Absent P waves, irregular R-R intervals, narrow QRS complexes. Originates in pulm veins --> atria develop shortened refractory periods and inc conductivity --> multiple ectopic foci
Triggers for vulvovaginal candidiasis
Abx use, high estrogen levels (pregnancy), systemic corticosteroid therapy, uncontrolled DM, immunosuppression and HIV
Reperfusion injury
Accelerated tissue death after resumption of blood flow: 1) oxygen free radical gen, 2) severe, irrev mito damage ("mitochondrial permeability transition"), 3) inflam which attracts circ PMNs, 4) activation of complement. In muscle, CK leaks across damaged cell memb
Thiolase
Acetyl-CoA + acetyl-CoA --> (thiolase) --> acetoacetyl-CoA + acetyl-CoA --> HMG-CoA, and HMG-CoA reductase (RLS in chol syn) catalyzes conversion of HMG-CoA to mevalonate
Diff in growth retardation in achondroplasia vs GH def
Achondroplasia - differentially affects long bones and not torso, GH def leads to proportionate short stature (long and flat bones affected)
Carbol fuschin (an aniline dye)
Acid-fast stain, stains for mycolic acids. Red mycobacteria and blue non-acid fast bacteria. AFB similar to Gram +ve, so stain weakly Gram +ve
Atypical (reactive) lymphocytes in EBV are which cell type?
Activated CD8+ T lymphocytes. EBV preferentially infects B cells by binding to CD21+ receptor --> CD8+ cells clonally expand in response, and become reactive
INF-g
Activates Mo, inc MHC expression, promotes Th1 differentiation. Prod by T cells and NK cells
Mechanism of insulin resistance due to TNF-alpha
Activation of serine kinases --> phosphorylate serine residues on beta subunits of IR and IRS-1
Acute vs chronic liver injury
Acute - deficiency of FVII (shortest half life of all coag factors) but normal albumin (long-half life, 20 d)
Severe right sided eye pain, ipsilateral HA, halos around objects
Acute angle-closure glaucoma
Complications of homocystinuria
Acute coronary syndrome (homocysteine is prothrombotic, predisposes to hypercoag and thromboembolic occlusion), ectopia lentis, intellectual disability
Travel to South America, elev AST/ALT, spotty hepatocyte necrosis and inflam cell infiltration
Acute hepatitis A infection. Sx: prodrome of fever, malaise, anorexia, N/V, RUQ pain. 1 wk later, jaundice, pruritis, dark-colored urine (inc conjugated bilirubin levels), acholic stool. Spotty necrosis w/ ballooning degen (hepatocyte swelling w/ wispy/clear cytoplasm), Councilman bodies (eosinophilic apoptotic hepatocytes), and mononuc cell infiltrates
Most common outcome of Hep B infection
Acute hepatitis w/ complete resolution. 4-5% of pts go on to chronic hepatitis, 50-80% of those remain stable w/ no cirrhosis
Alkylating agents and benzene exposure
Acute leukemias
Acarbose MOA
Alpha-glucosidase inhibitor that dec intestinal glucose absorption and blunts postpradial rise in serum glucose
Pt w/ Wernicke encephalopathy has what enzyme deficit in TCA?
Alpha-ketoglutarate dehydrogenase - Thiamine deficiency
Which dz is similar to pulmonary embolism?
Acute mesenteric ischemia (SMA embolism, sudden, severe abd pain)
Pt w/ abd pain and bloody diarrhea after complicated surgery
Acute nonocclusive ischemic colitis. Colon receives blood from artery of Drummond (SMA and IMA), and distal colon from int iliac a --> infarction causes acidosis, sepsis, gangrene, perforation
Acute stress d/o vs PTSD
Acute stress - 3 d to 1 mo, PTSD - >1 mo
Acute bacterial suppurative parotitis
Acute viral or bacterial infection of parotid gland, due to Staph aureus. RFs incl dehydration, intubation, salivary flow obstruction. Sx: acute firm, erythematous pre/post-auricular swelling extending to mandible. Detect by amyase
Drug that acts against HSV1/HSV2/VZV but not CMV/EBV
Acyclovir - guanosine analog. Inside HSV-infected host cell, it is phosphorylated to acyclovir monophosphate by a viral thymidine kinase (RLS in activation). EBV and CMV produce different TK --> not susceptible to acyclovir
Acyclovir nephrotoxicity
Acyclovir is excreted by tubular secretion --> can crystallize and cause renal tubular damage. Prevented by adequate hydration
Sympathetic receptors on pancreatic beta cells
Alpha2 - inhibit insulin release, beta2 - inc insulin release
Terminal deoxynucleotidyl transferase (TdT)
Adding nucleotides to VDJ regions of Ab, marker of immature lymphocytes
Summation
Additive effects of multiple postsynaptic potentials on a target neuron's memb pot. Temporal summ (sequential impulses from same neuron over time), spatial summ (simultaneous impulses from diff neurons)
Paraneoplastic syndrome of hypercoag
Adenocarcinomas of panc, colon, lung --> release of procoag tumor products, vasc stasis from tumor obstruction, pt immobility etc.
Regulators of coronary blood flow in autoregulatory range
Adenosine (vasodil in small coronary arterioles), NO (MOST IMPORTANT mediator of coronary vascular dilation in large arteries/pre-arteriolar vessels) released by endoth cells on coronary vasc, precursor is arginine),
Which drugs affect phase IV of pacemaker AP?
Adenosine and acetylcholine --> reduce rate of spont depol (inc K conductance, inhibit LTCC)
Coronary steal
Adenosine and dipyridamole are vasodilators of coronary vessels --> vasodil of coronary arterioles in nonischemic regions leads to diversion of blood to nonischemic areas --> hypotension and worsening of existing ischemia
Sx of endometriosis
Adhesion formation inteferes w/ ovulation and fallopian tube fcn --> infertility. Adhesions involve uterosacral lig --> fixed, retroverted uterus. Infiltration of post cul-de-sac causes painful intercourse, tenderness to palpation of post vaginal fornix
Acute adrenal crisis
Adrenal hemorrhage or infarction, acute injury/illness in pts w/ chronic adrenal insuff (Addison's) or long-term glucocorticoid use. Causes hypotension/shock, N/V, abd pain, weakness, fever. Tx: hydrocortisone/dexamethasone, high-flow IV fluids
Two exceptions to sympathetic pre and postgang scheme
Adrenal medulla (no postgang neuron, directly release NE and E into bloodstream), eccrine sweat glands (pre and postgang are cholinergic)
Hairy cell leukemia
Adult males, mature B-cell tumor, filamentous, hair-like projections. Marrow fibrosis --> dry tap on aspiration. Peripheral lymphadenopathy uncommon. Massive splenomegaly and pancytopenia, TRAP+. Tx: cladribine, pentostatin
Features of spinal metastases/malig back pain
Advanced age, pain worse at night, persistent and progressive pain not relieved by position change or analgesics. Systemic sx (fever, wt loss, night sweats), known hx of malig. Most commonly prostate cancer mets, or Pb Kettle
Fat embolism syndrome
Affects <10% of pts w/ severe skel injuries. Sx: pulm insuff, diffuse neuro impairment, thrombocytopenia, anemia. Fat globules from BM enter vasculature
H pylori gastritis
Affects antrum, acute (PMNs) or chronic (lymphocytes, plasma cells, lymphoid follicles). Antral involvement --> inc gastrin prod, duod ulcers. Body and fundal involvement --> loss of G cells, dec gastric acid prod, inc gastric adenocarcinoma
Monckeberg medial calcific sclerosis
Affects medium sized arteries, calcification of IEL and media --> vasc stiffening w/o obstruction, pipestem appearance on X-ray
Corneal reflex
Afferent ~ nasociliary branch of V1, efferent ~ VII
Carotid sinus pathway
Afferent: glossopharyngeal, efferent: vagus nerve. Vagus is also afferent for baroreceptors in aortic arch
Age of precocious puberty
Age <7
Medicare coverage
Age >= 65, younger individuals w/ disability, ESRD, ALS. Medicaid is state-run, Medicare is federal.
Side effects of antithyroid drugs
Agranulocytosis, hepatic failure (PTU), 1st-trimester teratogen (methimazole)
Microsomal monooxygenase
Aka CYP450 monooxygenase in hepatic microsomes. Metabolizes steroids, alcohol, toxins etc. Also converts pro-carcinogens into carcinogens (benzopyrene)
What are the only life threatening withdrawals?
Alcohol and benzos (w/d can cause sz in both). W/d start 12-24 after
Why can a pt maintain euglycemia early in a binge but not late?
Alcohol does not inhibit glycogenolysis, but after hepatic glycogen is depleted, GNG cannot occur and blood glucose levels drop
Presentation of aspiration pneumonia
Alcoholic, cavitary lesion with air-fluid levels, present days after aspiration event, fever, cough, inc sputum
Most common cause of folate def other than poor diet
Alcoholism
Clinical disinfectants
Alcohols (isopropanol, ethanol) ~ disruption of cell memb/denaturation of prots (do not destroy bacterial spores), chlorhexidine (used in surgeries, but neurotoxic) ~ disruption of cell memb/coag of cytoplasm, hydrogen peroxide ~ produces destructive free radicals that oxidize cellular components, iodine ~ halogenation of prots and nuc acids
Tarry stool and fatigue
Alkylating agents
Formaldehyde and glutaraldehyde
Alkylating and cross-linking DNA and prots
Contraindications to diazepam
All CNS depressants (alcohol, barbiturates, neuroleptics, 1st gen antihistamines - chlorpheniramine, diphenhydramine, promethazine, hydroxyzine)
Non-preventable adverse event
Allergic reaction to a medication in a patient with no known history of drug allergy
Allergic triad
Allergic rhinitis, atopic dermatitis, allergic asthma. If normal PFTs, can still be asthma --> do bronchoprovocation w/ methacholine challenge
Allocation vs selection bias
Allocation - assign patients nonrandomly, selection - studied sample does not reflect gen pop
Alpha and beta, power, Type I/II error
Alpha = accused an innocent man (false-positive error), beta = blindly let man go free (false-negative error). Power = 1-beta
Indications for particular antihypertensives
Alpha blockers (prasozin) ~ BPH, beta blockers ~ CAD/CHF, ACE-I ~ diabetes, HCTZ ~ first line med for tx of essential HTN, CCB ~ vasospasm (Raynaud's, Prinzmetal angina)
Lechithinase
Alpha toxin, produced by C perfringens, inc platelet aggregation
What is the universal amino group acceptor in aminotransferase rxns?
Alpha-KG. In liver, alanine + alpha-KG --> pyruvate + glutamate, and glutamate --> NH3 + a-KG, and ammonia enters urea cycle
Lispro
Alteration of insulin molecule at C terminal of insulin B chain prevents polymerization
Pathophys and precipitators of sickle cell dz
Alternation of hydrophobic beta globin chain fitting into complementary site on alpha globin chain --> aggregation under anoxic conditions (low O2, inc pH, dehydration)
Mechanism used by cancer cells to truncate Fas prots
Alternative splicing
Which two drugs given to a-fib pts may cause bleeding by CYP450 interactions?
Amiodarone and warfarin
Amniotic fluid embolism (fetal squamous cells in maternal pulm a)
Amniotic fluid containing arachidonic acid metabolites enters maternal circ thru uterine trauma/cervical lacerations --> anaphylaxis (cardiogenic shock, hypoxemic resp failure, DIC, sz or coma)
Plasma renin activity (PRA)
Amt of angiotensin I gen per unit of time, assesses fcn of RAAS.
Inhaled amyl nitrite and cyanide tox (other antidotes are hydroxycobalamin and sodium thiosulfate)
Amyl nitrite oxidizes ferrous iron in Hb to Fe3+ --> generates methemoglobin, which is unable to bind O2 but has high affinity for cyanide. Sequesters cyanide in bloo, freeing it from cytochrome oxidase and limits toxic effects.
Which panc enzyme does not require activation by trypsin?
Amylase and lipase (causes calcium soap deposits - fat necrosis)
Which muts are assoc w/ early-onset AD?
Amyloid precursor prot on chrom 21, presenilin 1 on chrom 14, presenilin 2 gene on chrom 1
26M playing professional sports w/ comedonal and inflam nodular acne on face, chest, back
Anabolic steroid use. Pt has passed the age of pubertal androgen surge. Methyl-T promotes follicular epidermal hyperprolif and excessive sebum prod
Conditions of polygenic inheritance
Androgenetic alopecia (begins at temporal areas and vertex), epilepsy, glaucoma, HTN, ischemic heart dz, schizophrenia, T2DM
Negative skin TST after M tb exposure
Anergy against B Ags --> weak cell-mediated immune response
Aneurysmal compression of CN III vs diabetic ophthalmoplegia. In short, diabetic mononeuropathy spares peripheral parasymp fibers (down and out but normal pupillary size and reactivity), whereas external compression by aneursym or tumor causes down and out, dilated pupil and loss of accommodation.
Aneurysm - compresses superficial parasymp efferents: early - dilated pupil and loss of accommodation, late - ptosis and "down and out". Diabetic - sparing of superficial parasymp: down and out, normal sized reactive pupil, ptosis
Most common cause of CN III palsy
Aneurysm of the PCA
Causes of TOS
Anomalous cervical rib, scalene muscular anomalies, injury (reptitive overhead arm movements, trauma)
Causes of osteogenesis imperfecta
Problem forming triple helix (glycosylation of pro-alpha-chain hydroxylysine and formation of procollagen)
Pheochromocytoma
Arise in adrenal medulla (paraganglioma if outside). 25% inherited (VHL, RET, NF1). Rule of 10s: 10% bilat, 10% extra-adrenal, 10% malig
Widened, ascending thoracic aorta w/ nonenhancing "septum" on CT
Aortic dissection (septum is tunica intima of aorta that has been torn from aortic wall) - HTN is single most imp risk factor for aortic dissec (3° syphilis ~ ascending aortic aneurysm, hypercholemia ~ abd aortic aneurysm)
Councilman/apoptotic body
Apoptotic hepatocytes form round acidophilic bodies
Pick bodies
Appear in FTD (Pick dz), silver staining shows round cytoplasmic inclusions containing aggregates of Tau
What signals irrev cell injury?
Appearance of vacuoles and phospholipid containing amorphous densities w/in mito --> permanent inability to gen ATP by ox phos
Leukocyte interferon-alpha
Approved for tx of Hep B and C, hairy cell leukemia, condyloma acuminatum, Kaposi's sarcoma
Pharyngeal arches and the nerves they are innervated by
Arch 1 ~ CN V, arch 2 ~ CN VII, arch 3 ~ CN IX, arch 4/6 ~ X
Area postrema and NTS
Area postrema - CTZ, responds to NTs, drugs, toxins. NTS - in medulla, receives info from area postrema, vagus n (GI) etc.
What is given in hyperammonemia for pts w/ urea cycle d/o?
Arginine administered for prod of downstream water-soluble intermediates --> nitrogen disposal and dec plasma ammonia
Tensor tympani muscle
Arises from cartilagenous portion of auditory tube and inserts into malleus. Contracts tympanic memb medially, dampens sound transmission. Innerv by CN V3
Psoas abscess
Arises from transverse processes and lateral aspects of 12th thoracic thru 5th lumbar vertebrae. Direct (vertebral body) spread or hematogenous, RFs incl DM, IVDU, HIV
Nitrate tolerance
Around-the-clock nitrate administration leads to tachyphylaxis --> dec vasc sensitivity to nitrates, inc sensitivity to vasoconstrictors. Must have nitrate-free interval daily
Garlic breath after insecticide ingestion, vomiting, watery D
Arsenic poisoning (also from contaminated water). Tx: dimercaprol
How does surfactant counteract distending pres?
As inside area of the sphere dec, surfactant becomes more []ated and can dec surface tension more; and vice versa. Physiologically, surfactant prevents small alveoli from collapsing during expiration, and regulates alv expansion during inspiration
Cardiac findings of syphilis
Ascending aortic aneurysms --> may lead to aortic valve insuff (murmur, high-pitched tambour S2). NEUROSYPHILIS CAN OCCUR AT ANY STAGE, but commony late syphilis manifestation.
Guillain-Barre syndrome
Ascending symmetric weakness following URTI or Campy diarrhea, areflexia, eventual resp failure. Endoneurial inflam infiltrate (lymphocytes and Mo, lipid laden Mo after engulfment of myelin)
Asparaginase
Asparagine is an essential AA for tumor cells that are dividing too rapidly to produce it (asparagine synthase converts aspartate to asparagine)
Why is Toxo a concern for HIV pts and not Aspergillus?
Aspergillus is destroyed by phagocytic function, which is preserved in HIV (only T cell dysfcn)
Zika virus
Assoc w/ GBS, pruritic maculopapular rash, low-grade fever, arthralgias, conjunctivitis
DIC
Assoc w/ Gram negative sepsis, exposure to procoagulants and subsequent compensatory thrombolysis causes consumption of coag factors, bleeding
Loss of E-cadherin
Assoc w/ metastasis and predictor of dz progression in some cancers
Inferior thyroid artery injury
Associated w/ hoarseness b/c it runs alongside recurrent laryngeal n. Hoarseness ~ unilat nerve injury, complete vocal cord paralysis/insp stridor/resp distress ~ bilat injury
Degenerative mitral and aortic valve calcification
Associated with systemic hypertension
Work of breathing optimization
At high tidal vol, work done against elastic resistance inc (recoil of lung); at low tidal vol, work done against airflow resistance inc (collapsed aws)
Blue toe, livedo reticularis, normal peripheral pulses
Atheroembolic disease, cholesterol-containing debris dislodged from larger arteries after invasive vascular procedure. AKI is most common presenting sx of postprocedure atheroembolism, no frank infarction w/ flank pain and hematuria b/c chol emboli are small --> needle-shaped chol clefts in arterial lumen
Cortical vs lacunar infarcts
Atherosclerotic emboli from carotid/heart cause cortical infarcts, lipohyalinosis from chronic HTN (hypertensive arteriolar sclerosis) causes occlusion of small penetrating arterioles and cavitary infarcts in basal ganglia, post limb of int capsule, pons, and cerebellum
Patients w/ severe AS depend on what to maintain LV filling?
Atrial contraction - severe AS impairs LV output, and higher systolic pres cause LVH. Loss of atrial kick --> hypotension, buildup of blood in LA/pulm vv --> acute pulm edema
Presystolic accentuation
Atrial contraction in late ventricular diastole causes increase in intensity of diastolic murmur before S1
Histopath of systemic sclerosis
Atrophy of muscularis w/ collagenous fibrosis
Pathology of endometrial adenocarcinoma
Atypical endometrial cells, disorganized glands, and multiple mitoses. Postmenopausal women, vaginal bleeding
Indicator of severity of MR
Audible S3 gallop (higher vol of regurgitant blood flow/more dilated LV is more likely to produce S3). Absence of S3 = no severe chronic MR
Alpha-1 AT def
Aut codom d/o, affects lungs and liver, inhibits neutrophil elastase. Liver involvement in first 2 decades: intrahepatocyte accum of polymerized AAT --> cirrhosis and HCC. Intracellular granules of unsecreted AAT in periportal hepatocytes, reddish-pink on PAS and diastase resistant. A1AT def also causes panacinar emphysema, esp LOWER LOBE PREDOMINANT (greater perfusion in lower lobes permits greater rate of PMN/neutrophil elastase entry) (takes decades to develop - dyspnea at 36 in smokers w/ A1AT def, 51 in nonsmokers), smoking is synergistic (induces lung inflam, permanently inactivates A1AT by oxidizing methionine residue).
Most common cause of 1° adrenal insuff
Autoimmune adrenalitis (destroys all 3 layers of adrenal cortex). Dec Na reabsorption, dec K and H excretion. Metabolic acidosis causes net Cl reabsorption as counterion. No electrolyte abnormalities in 2° or 3° adrenal insuff
HIT
Autoimmune phenomenon, arterial and venous thrombosis. Thrombocytopenia
Anterior disloc of shoulder or humeral neck fracture
Axillary n injury
Drugs that cause gallstones
Azathioprine, sulfasalazine, furosemide, valproic acid
First dose effect
Cause hypotension when tx is first started, ameliorated by starting w/ small first dose
Advantages of celecoxib and risks
Celecoxib has less risk of GI ulceration and bleeding (inhibition of COX1 causes gastric ulceration and bleeding). COX2 expressed on vasc endoth cells and prod prostacyclin (anticoag/vasodil effects) --> celecoxib inc risk of CV events
How does crutch palsy differ from screwdriver injury?
Both are radial nerve injuries, but former causes wrist drop and absent triceps reflex, whereas latter spares sensation and preserves triceps. Injury at midshaft humerus (radial groove) causes sensory loss over posterior forearm/dorsolat hand
Vitamin deficiencies
B7 ~ pyruvate carboxylase, B1/B2/B3/B5 ~ pyruvate dehydrogenase, B6 ~ alanine transaminase, B2 ~ succinate dehydrogenase, B3 ~ malate dehydrogenase
Which mutation is hereditary 1° arterial hypertension assoc w/?
BMPR2. Tx of PAH is bosentan, other meds won't work (aldo antag, ARBs, BB used for 2° pulm HTN due to L sided HF)
Class III antiarrhythmics
Block K chan, inhibit outward K current during Phase 3. Maintenance of sinus rhythm in pts w/ paroxysmal a-fib
Interscalene nerve block
Block brachial plexus roots and trunks, and cause transient ipsilat diaphragmatic paralysis
Chordae tendinae rupture producing severe MR
Bacterial endocarditis, acute MI (<10 d)
Peripheral smear findings after decompensation in meningococcal meningitis
Bacterial endotoxins lead to widespread fibrin deposition --> DIC --> excess fibrin shears RBCs --> schistocytes
Pityriasis rosea
Begins with herald patch (solitary pink or brown scaly plaque with trailing scale), spreads as reverse Christmas tree. Tinea ~ leading scale
Conduct disorder
Behaviors are more severe and aggressive than ODD (physical aggression or cruelty towards animals, destruction of property, stealing/deceit; inc risk of antisocial PD)
Familial hypocalciuric hypocalcemia
Benign AD d/o, defective Ca sensing in parathyroid and renal tubular cells --> inadequate PTH suppression, hyperCa
Reninoma
Benign juxtaglomerular cell neoplasm, causes 2° hyperaldosteronism
Leukemoid reaction
Benign leukocytosis (>50,000/mm^3) in response to severe infection, pneumonia, sepsis, solid tumor, acute hemolysis. Peripheral smear shows Dohle bodies (light blue basophilic peripheral granules in PMNs)
Hamartoma
Benign lung tumor detected incidentally on CXR. Peripheral "coin lesion", mature hyaline cartilage mixed w/ CT, SM, and fat
Schwannomas
Benign tumors arising from vestibular branch of CN VIII at cerebellopontine angle, Verocay bodies composed of eosinophilic cores (Antoni A pattern)
Cystic hygromas (lymphangiomas) - TURNER
Benign tumors consisting of dilated lymphatic spaces lined by endothelium, occur in neck and transilluminate. Found in neonates w/ Turner's or Down's
Immediate tx of panic d/o
Benzos. SSRIs and SNRIs are first-line pharm tx for panic d/o but take weeks to begin working
Tx of drug-induced parkinsonism vs akathisia
Benztropine vs propanolol
Uterus and pupillary dilators have which adrenergic receptors?
Beta-2 and alpha-1, respectively
Pt w/ ASCVD whose angina and chest pain relieved, but asthma exacerbated
Beta-blocker. Used in emergent tx of pts w/ ACS b/c of impromved mortality, but also cause nonspecific beta-adrenergic blockade --> bronchoconstriction
Effect of beta-glucuronidase on gallstones
Beta-glucuronidase (released by damaged hepatocytes and bacteria) deconjugates bilirubin glucuronides --> pigmented gallstones.
What happens in mitochondria?
Beta-ox of FAs, citric acid cycle, carboxylation of pyruvate (GNG)
Significance of elevated HbA2 and effect on HbA1c
Beta-thal (HbA2 elevated to compensate for beta chain underprod) --> Microcytic red cells prone to hemolysis --> inc RBC turnover --> falsely low HbA1c
Postoperative urinary retention
Bethanechol. Anesthesia and analgesia cause overdistension of bladder, decreased micturition reflex, dec contractility of detrusor
Medical tx of biliary colic due to chol gallstones
Bile acid supplementation (ursodeoxycholic acid)
Which dz is similar to diffuse esophageal spasm?
Biliary colic (gallbladder contraction against an obstructed cystic duct results in postprandial epigastric pain)
Orotic acid excess (citrullinemia, ornitine transcarbam def)
Block in urea cycle leads to excess carbamoyl phosphate, metabolized by dihydroorotate dehydrog to orotic acid. Hyperammonemia, excess amts of orotic acid
MOA of benzos
Bind allosterically to GABA_A receptor complex, that has 5 subunits and a central Cl channel
Cyanide toxicity
Binds ferric iron w/ high affinity --> inhibits cytochrome c oxidase in mito --> lactic acidosis, narrowed PamvO2 (inability of tissues to extract arterial oxygen). Sx: reddish skin discoloration, tachypnea, HA, tachycardia, N/V
MOA of Protein A
Binds the Fc portion of IgG Abs at the complement-binding site, preventing complement activation --> dec C3b prod, impaired opsonization and phagocytosis
Transcription factor Iid
Binds to TATA promoter sequence to initiate gene transcription
MOA of doxo/daunorubicin
Binds w/ topoisomerase II to cleave DNA, and binds w/ iron to gen free radicals
First committed step of GNG (pyruvate carboxylase and PEPCK work together to bypass pyruvate kinase)
Biotin-dep carboxylation of pyruvate to oxaloacetate by pyruvate carboxylase. Malate shuttle for OA to leave mito, and PEPCK converts OA to PEP.
Three proven beta blockers for CHF
Bisoprolol, carvedilol, metoprolol
Bitemp vs binasal hemianopsia - compression where?
Bitemp - medial optic chiasm (note that temporal visual info goes to nasal fibers), binasal - lateral optic chiasm
Osmium tetroxide
Black color to fat, used to visualize fat (such as in fat embolism syndrome after broken bone).
Pigment stones
Black stones (chronic hemolysis from sickle cell, spherocytosis or inc enterohepatic cycling of bilirubin from ileal dz), or brown stones (biliary tract infection by E coli or liver fluke - EAST ASIANS). Microorganisms release beta-glucuronidases --> cleave conjugated bilirubin into unconj, form gallstones.
Anatomy of bladder
Bladder is extraperitoneal, thus as it fills and bulges upward, it comes into direct contact w/ ant abd wall antinf to peritoneal space. In a suprapubic cystostomy, trocar and cannula pierces aponeurosis of abd wall muscles (not peritoneum!)
Norepinephrine extravasation
Blanching of a vein into which NE is being infused, induration, and pallor of the tissues surrounding the IV site. Tx: give phentolamine w/in 12 h
Uterine atony
Boggy uterus that cannot contract effectively after placental delivery, surgery indicated if uterine massage and uterotonic meds fail to control postpartum hemorrhage. RFs: prolonged labor, twin gestation
Bortezomib
Boronic acid-containing dipeptide - protease inhibitor used in tx of multiple myeloma --> excess of pro-apoptotic proteins, promotes apoptosis of plasma cells
Pharmacologic tx of pulm HTN before lung transplant
Bosentan (endothelin-receptor antag)
E coli vs Enterobacter cloacea
Both are common causes of UTI, both are fast lactose fermenters and GNRs. Only E coli is indole +ve
How to differentiate b/n large pleural effusion and collapsed lung?
Both have complete opacification of a hemithorax, but pleural effusion and tension pneumothorax cause tracheal deviation away (excess fluid pushes), and collapsed lung has tracheal deviation towards (opacification is from structures filling up atelectatic lung)
MAC vs M tb
Both have fever, wt loss, and diarrhea. However, MAC in HIV pt has marked anemia, hepatosplenomegaly, and elev ALP and LDH
Contrast botulism with other ACh diseases
Botulism = nicotonic and muscarinic blockade, improves w/ repetitive stim. MG = Abs against postsyn nAChR, no muscarinic sx, does not improve w/ repetitive stim. LEMS = muscarinic sx, improves w/ repetitive stim, starts in LE. TCA overdose = muscarinic blockade, no nicotonic blockade, no effect on CMAP
Aortic regurg
Bounding pulses, wide pulse pressure, diastolic heart murmur, HEAD BOBBING
What part of nephron has lowest PAH concentration?
Bowman's space. Some PAH is filtered in glom, but most is actively secreted in PCT.
Supracondylar fracture of humerus
Brachial a
Derivatives of neural tube
Brain and spinal cord, posterior pit, pineal gland, retina
Cutaneous innervation of the ear
Branch of facial, auricular branch of vagus (X), auriculotemporal (V3), lesser occipital (C2, C3), greater auricular (C2, C3)
Three most common cancers in women in US
Breast, lung, colon
Cataplexy
Brief loss of muscle tone precipitated by strong emotion (laughter, excitement). Hypnagogic - on sleeping, hypnapompic - on waking
Restore fertility in women w/ hyperprolactinemia
Bromocriptine - dopamine receptor agonist
Types of chronic transplant rejection
Bronchiolitis obliterans (lung, submucosal lymphocytic infiltration), accelerated atherosclerosis (heart), chronic graft nephropathy (kidney), vanishing bile duct syndrome (liver)
Non-lobar types of pneumonia
Bronchopneumonia - infection of terminal bronchioles resulting in patchy consolidation of many lobules. Also interstitial pneumonia
S/e of BB
Bronchospasm, bradycardia, fatigue, sexual dysfcn
Acute and painless monocular vision loss
Central retinal artery occlusion, permanent. Pale retina (due to ischemia and edema), cherry-red macula (fovea have a separate blood supply from choroid a). CRA is branch of ophthalmic which comes off ICA --> atheroembolism is most common cause of CRAO
Brown vs white fat
Brown fat has several small intracytoplasmic fat vacuoles, considerably more mito
Distal LE vasc insuff and hypersensitivity to tobacco smoke
Buerger's - segmental vasculitis extending into contiguous veins and nerves (esp tibial and radial aa). Seen in Israel, Japan, India. Calf/foot/hand intermittent claudication, Raynaud's, distal pain, gangrene of toes
Diffuse medium-sized lymphocytes around small intestine, high Ki67
Burkitt lymphoma, starry sky appearance, preexisting immunodef 2° to HIV infection can potentiate EBV Ag-induced B-cell prolif
High mitotic index (high Ki-67)
Burkitt's lymphoma. Tingible-body macrophages are seen (benign Mos that phagocytize the resulting cellular debris)
Glioblastoma multiforme
Butterfly glioma (bilateral symmetric lesion crossing corpus callosum. Poorly-diff, pleomorphic astrocytic cells, nuc atypia, pseudo-palisading necrosis)
Why is dietary fructose rapidly metabolized?
Bypasses PFK-1 in the glycolytic pathway
Macular lesions result in what?
Central scotomas due to MS, diabetic retinopathy, retinitis pigmentosa, macular degeneration - deposition of Drusen (dry) or neovasc of retina (wet)
CLEAVED NUCLEI (small lymphoid cells)
Centrocytes of follicular lymphoma
Acute, painless, monocular vision loss
Retinal artery occlusion (ICA --> ophthalmic --> retinal a)
Three phases of acid secretion in stomach
Cephalic: mediated by cholinergic and vagal mech, triggered by sight/thought/smell of food, gastric: presence of gastrin, intestinal: protein-containing food enters duod, ileum and colon release peptide YY --> binds to ECL, SMS, PG downregulate acid
Most serious long term s/e of chloroquine use
Retinopathy. Primaquine CI in pts w/ G6PD def
CXR findings of acute decompensated HF
Cephalization of pulm vessels, perihilar alveolar edema, blunting of costophrenic angles (pleural effusions). Kerley B lines - short horiz lines situated perpendicularly to pleural surface, represent edema of interlobular septa
Lumacaftor and ivacaftor
CFTR-modulating meds, restore CFTR to membrane and enhance prot fcn
Low sperm vol and low pH of ejaculate
CBAVD
HIV ART meds
CCR5 antag ~ maraviroc, fusion inhibitor ~ enfuviritide, integrase inhib ~ dolutegravir/raltegravir, PI ~ -navir, NNRTI ~ efavirenz, nevirapine
Diarrhea of CD vs UC: bloody?
CD - DIARRHEA MAY OR MAY NOT BE BLOODY. UC - bloody
CD15, CD16
CD 15 is present on granulocytes and all Reed-Sternberg cells (good marker for Hodgkin's). CD16 - surface of NK cells, PMNs, Mo
Vascular tumor, past arsenic exposure, CD31
CD31 (PECAM) --> vascular endothelial cells. Liver angiosarcoma
HIV-associated dementia
CD4 < 200, subcortical dementia (attention/working memory problems, executive dysfcn), due to inflam cytokine release by Mo/microglia
Th1, Th2, Th17 are subtypes of what T cell?
CD4. M tb has inc CD4 (Th1), macrophages
Failure to turn blue w/ nitroblue tetrazolium dye and dec fluorescence on dihydrorhodamine (DHR) flow cytometry
CGD, X-linked mut in NADPH oxidase --> catalase +ve organisms survive, b/c they can metabolize their own ROS.
Why do pts w/ CHF have Cheyne-Stokes breathing?
CHF has chronic hypervent w/ hypocapnia --> apnea causes excessive buildup of CO2, crosses apneic threshold --> hyperpnea, overshoots. Also prolonged circ time b/n lungs and brain, discrepancy in PaCO2 sensed by central chemoreceptors and PaCO2 in alveoli
Which cancers have transloc and constitutively active RTK?
CML (BCR/ABL) and NSCLC (EML4/ALK). Latter is targeted by crizotinib. Often seen in young non-smokers, often w/ adenocarcinoma
BCR/ABL
CML, t(9:22), codes for abnormal tyrosine kinase
Owl eye inclusions
CMV or Hodgkin's (Reed-Stenberg)
SOB, nonprod cough, low-grade fever, intranuc and intracyto inclusions after lung transplant
CMV pneumonitis esp common in lung transplants, has owl eye inclusions. Universal valganciclovir proph for lung transplant pts
UNCAL HERNIATION
CN III PALSY
Brain regions supplied by PCA
CN III and IV, midbrain, thalamus, medial temporal lobe, splenium of corpus callosum, parahippocampal grus, fusiform gyrus, occipital lobe
Contents of IOF
CN V2, infraorbital vessels, branches of sphenopalatine ganglion
COX1 vs 2
COX1 - EVERYWHERE (incl platelets and GI tract --> COX1 blockers cause bleeding and GI ulceration), COX2 - AT SITES OF INFLAMMATION (endothelium)
S/e of celecoxib (COX2 inhibitor)
COX1 and 2 found in kidney (s/e is fluid retention, aggravation of HTN), and vasc endothelial cells and SM (s/e is inc CV events from dec prostacyclin)
Syringomyelia
CSF-filled cavity (syrinx) forms in cervical region of SC (C8-T1) --> ventral white commissure damaged, lateral spinothalamic tract fcn impaired
Mycosis fungoides
CTCL. Prolif CD4 lymphocytes invade the dermis and epidermis, form Pautrier microabscesses. Manifests w/ plaques (on trunk or buttocks) that may be confused w/ eczema or psoriasis
Nodular lymphoid hyperplasia
CVID, low Ig and B lymphocyte levels
Why drugs can trigger statin-induced myopathy?
CYP450 3A4 inhibitors (cimetidine, erythromycin etc.) affect all statins except pravastatin
Ranke complex
Calcified lower lobe nodule and ipsilat hilar lymph node seen on CXR several mos after 1° TB
Diet of pt w/ pyruvate dehydrogenase deficiency
Can't process any glucogenic foods --> must have ketogenic diet (lysine, leucine)
Pt receiving TPN thru central venous catheter, develops F and chills
Candidemia
Esophageal or duodenal atresia effect on amniotic fluid
Cannot absorb swallowed amniotic fluid --> polyhydramnios
Tx of trigeminal neuralgia
Carbamazapine - car in drive-thru below 3 gems. S/e incl BM suppression, SIADH
Drugs that cause SIADH
Carbamazepine, cyclophosphamide, SSRIs
Treatment of choice for ESBL-producing E coli
Carbapenems
Effect of adding carbidopa to levodopa
Carbidopa inhibit peripheral conversion of levodopa --> dec peripheral sx (tachyarrhythmias, postural hypotension, hot flashes), but inc neuro sx (agitation/anxiety)
Mechanism of glaucoma meds
Carbonic anhydrase inhibitors (dorzolamide) - dec formation of bicarb in ciliary body, dec Na, dec prod of aqueous humor; alpha agonists (brimonidine) - vasoconstrict ciliary body, dec prod of aqueous humor; beta blockers (timolol) - dec prod of aqueous humor
Lightning-rel complications
Cardiac (cardiac arrest, arrhythmia), neuro (peripheral nerve damage, sz, confusion, autonomic dysfcn - fixed/dilated, asymmetric pupils), derm (Lichtenburg figures - erythematous fern-leaf marks, burns), MSK (rhabdo, bone fractures), other (cataracts, ruptured tympanic memb, curling ulcers)
S/e of amIODarone (IODine in thyroid)
Cardiac (sinus bradycardia, heart block, QT prolongation), pulm (chronic interstitial pneumonitis), endocrine (hypo/hyperthyroidism), GI (elev AST/ALT, hepatitis), ocular (corneal micro-deposits, optic neuropathy), derm (blue-grey skin discoloration), neuro (peripheral neuropathy)
Conduction block
Cardiac myocyte degeneration below the level of the AV node
Causes of pulsus paradoxus
Cardiac tamponade, severe asthma, COPD, hypovolemic shock, constrictive pericarditis
Most common cause of iatrogenic phrenic n injury
Cardiothoracic surg --> nerve damaged where it passes b/n pericardium and mediastinal pleura --> diaphragmatic paralysis
Fall on outstretched hand, dislocation of lunate
Carpal tunnel syndrome
Glucose is transported by what mechanism in adipocytes?
Carrier-mediated (GLUT4). RME ~ LDL-R, 2° active ~ Na/glu symporter in intestinal and renal tubular epith
Posterior limb of the internal capsule
Carries corticospinal motor and somatic sensory fibers as well as visual and auditory fibers. Separates globus pallidus and putamen from thalamus.
Case control vs cohort
Case control is retrospective (group by events), cohort is prospective (group by exposure)
RR cannot be calculated in which studies?
Case-control - pts are preselected based on dz status
Which CD is seen in 2° TB?
Caseating granulomas made of Mo, and CD14 is surface marker of monocyte-Mo lineage
MOA of lactulose
Catabolized by intestinal bacterial flora into SCFAS, lowering the colonic pH --> inc conversion of ammonia to ammonium
Most common agents affecting SCD pts
S pneumo, H flu, N mening. If asplenic and has osteomyelitis, get Salmonella.
ARPKD
Caused by mut in PKHD1, codes for fibrocystin. Clinical findings are bilat enlarged, cystic fetal kidneys and oligohydramnios. Leads to oligohydramnios in utero b/c amiotic fluid = fetal urine
Posterior vaginal wall prolapse (rectocele)
Causes constipation and sx of pelvic pressure, splinting is common. Premenopausal, nonobese, nulliparous women are at lowest risk
Isospora belli
Causes profuse watery diarrhea in pts w/ HIV
Cardiac tamponade
Causes: malig/radiation therapy, infection (viral, TB, HIV), drugs (hydralazine, isoniazid), CT dz (SLE, RA). Beck's triad, pulsus paradoxus. Dx: ECG (low-voltage QRS, electrical alternans), CXR (water bottle shaped heart clear lungs)
Sinus infections
S pneumoniae, H flu, Moraxella catarrhalis
What mediates insulin deficiency in T1DM?
Cell-mediated immunity (autoimmune response to panc beta cells). Sx appear once >90% of beta cells are destroyed. Islet cell Abs are permissive but not primary
Pathogenesis of GCA
Cell-mediated processes (inflammatory infiltrate composed of CD4+ T cells and macrophages, frequently multinuc giant cells). IL-6 closely correlated to dz severity, tocilizumab (IL-6 mAb) treats GCA
NF2
Central neurofibromatosis, NF2 TSG mutation (encodes protein merlin), chrom 22, sx: bilat acoustic neuromas
What complication is commonly found in ADPKD pts?
Cerebral aneurysms
Erythema nodosum
S pyogenes pharyngitis (JONES), Staph aureus, coccidio, histo, blasto, chlamydia, IBD, sarcoid
Tx of Wilson dz
Chelators (D-penicillamine, trientine), zinc (interferes w/ copper absorption). Copper normally binds cellular proteins by sulfhydryl groups, and D-penicillamine has a free sulfhydryl
Cyanide poisoning
Cherry red skin, abdominal pain, vomiting, lactic acidosis, AMS, sz. Tx: sodium nitrite, sodium thiosulfate, hydroxocobalamin
Acute epiglottitis
Cherry-red swollen epiglottis, dysphagia, drooling --> H flu type b
Specific findins for cocaine vs other stimulants
Chest pain (potent vasoconstrictor --> myocardial ischemia), seizures, mydriasis. Other sx include euphoria, agitation/psychosis, tachycardia/hypertension. Intranasal cocaine use --> vasoconstriction and local ischemia --> mucosal atrophy and nasal septal perforation (highly specific findings)
Interventricular septum perforation
Chest pain, SOB, sx of cardiogenic shock, harsh holosystolic murmur on L sternal border
HSP
Children age 3-10, follows URTI, due to circ IgA-Ag immune complexes (Type III hypersensitivity)
Congenital torticollis
Chin point away from contracted muscle, contracted SCM, head tilted towards affects muscle. Develops at age 2-4 wks, caused by birth trauma (breech delivery) or malrotation of head in utero (fetal macrosomia/polyhydramnios)
LGV
Chlamydia trachomatis, L serovars - painless initially, but then painful lymphadenitis/buboes, small and shallow ulcers, chlamydial inclusion bodies, lymphadenopathy. Long-term, can cause fibrosis, lymphatic obstruction, anogenital strictures/fissures
Causes of aplastic anemia
Chloramphenicol, parvovirus B19 or sickle cell dz
Rate limiting step in synthesis of bile acids
Cholesterol 7alpha-hydroxylase, blocked by fibrates --> dec chol solubility in bile b/c no bile acid prod --> precipitates chol gallstone formation
Pt w/ testicular mass and hyperthyroidism
Choriocarcinoma - produces hCG, which is structurally similar to TSH --> hyperthyroidism (beta subunits of hCG and TSH are very similar)
Causes of pulm HTN
Chronic lung dz, L HF, 1° PAH (BMPR2 mut, women 20-40). DOUBLE HIT HYPOTHESIS: BMPR2 predisposes to vSMC prolif, second hit (drugs, infection) increases endothelin prod and dec NO and prostacyclin levels --> intimal hyperplasia and fibrosis, medial hypertrophy, formation of capillary tufts/onion skinning
Collagenous colitis
Chronic watery diarrhea (>5-10 episodes/d), seen in middle-aged women
Stasis dermatitis
Chronically inc intraluminal pres causes dilation of veins and incompetence of valves --> venous stasis causes poor wound healing, dermatitis, iron deposition, brawny discoloration
Risk factors for esophageal SCC
Cigarette smoking, etoh use, achalasia
CYP450 inhibitors
Cimetidine, ciproflox, macrolides, verapamil
Which med can cause theophylline toxicity as tx for UTI?
Ciproflox - CYP450 inhibitor. Theophylline is adenosine receptor antag and PDE-I, causes bronchodil by inc cAMP. Narrow TI: sz, tremor, insomnia, cardiac arrhythmias
Tx of ETEC
Ciprofloxacin or another fluoroquinolone
Mitochondrial DNA
Circular DNA that encodes 14 proteins, and rRNA and tRNA needed for mito prot syn
Detection methods for viruses
Circulating surface Ag ~ Hep B, cryoglobulins ~ Hep C, hemagglutinin ~ influenza/parainfluenza
Presentation of hemochromatosis
Cirrhosis, panc fibrosis, diabetes, cardiomyopathy, secondary hypogonadism
Use dependence
Class I antiarrhythmics bind channel during open or inactivated states, but dissociate during resting state --> tissues undergoing frequent depol are more susceptible to blockage
Gross painless hematuria in old person, copious amt of IC glycogen and lipids
Clear cell carcinoma (most common form of RCC)
Neuraminidase
Cleaves sialic acid off host glycoprots - inc free sugar in resp tract, fosters bacterial growth
Cause of cleft lip and cleft palate
Cleft lip - maxillary prominence fails to fuse with intermaxillary segment (5-6th week). Cleft palate - palatine shelves fail to fuse (7-8th week). Each can occur indep of other
Presentation of velocardiofacial syndrome
Cleft palate, cardiac abnormalities, dysmorphic facies (orbital hypertelorism, short palpebral fissures, shot philtrum, cleft palate, bifid uvula). Cardiac defects incl interupted aortic arch and ToF
Restore fertility in normogonadotropic, normoprolactinemic, euthyroid women w/ ovulatory failure
Clomiphene - stimulates ovulation by blocking feedback inhibition of estrogen on hypo --> release of pit gonadotropins
Tx of PCOS for woman who wants to become pregnant
Clomiphene or letrozole (induce ovulation). Wt loss first-line, OCPs for women who do not wish to become pregnant
Tx of treatment-resistant schizophrenia
Clozapine
Congenital cardiac anomaly assoc w/ spont ICH
Coarctation of aorta (may also be assoc w/ berry aneurysms of CoW)
Sequelae of Turner syndrome
Coarctation of aorta, bicuspid aortic valve, horseshoe kidney, streak ovaries
Appearance of fungi
Coccidio - thick-walled spherules w/ endospores; Paracoccidio - multiple blastoconidia, cells covered in budding blastoconidia; Aspergillus - 45°; Blasto - large, round yeast w/ doubly refractile wall and single broad-based bud; Crypto - yeast w/ thick capsule and narrow-based buds; Histo - small oval yeast w/in Mos; Rhizopus - only mold form, broad ribbonlike hyphae w/ rare septations; Sporothrix - localized to wound, conidia on hyphae, round or cigar shaped budding yeasts; Candida - small oval yeast w/ narrow-based budding
Several days of cough and fever, hilar adenopathy, thick walled spherules on lung tissue
Coccidioides - tumbleweeds
Which gout medication causes N/V/D?
Colchicine - interrupts rapidly dividing cells in the GI tract
Tx of acute gout attack in pt w/ PUD
Colchicine, NSAIDs are CI
vWF binds to what?
Collagen (promotes platelet adhesion) and Factor VIII (carrier)
Decreased breath sounds, hemithorax on R, deviation of trachea towards opacified side
Collapsed lung due to bronchial obstruction, usually due to obstruction of mainstem bronchus (central lung tumor in chronic smokers) --> atelectasis, trachea deviates towards collapsed side. Shifting of organs into hemithorax causes complete opacification on CXR
Where do uric acid crystals precipitate?
Collecting ducts (lowest pH is here).
Congenital communicating hydrocele
Collection of peritoneal fluid w/in the tunica vaginalis, transilluminates. C.f. indirect inguinal hernia in UWorld tables tab
Coltivirus (Reoviridae)
Colorado tick fever, Rocky Mountain states - fever, vomiting, myalgias, weakness, no rash
Glandular endocervical cells
Columnar cells w/ vacuolated or granular cytoplasm, honeycomb like pattern when in clusters
Supracondylar humerus fractures (brachial a and median n run med, radial n runs lat)
Common after hyperextension injuries (fall onto outstretched arm). Frac causing anterolat displacement of prox frac frag --> radial n injury; anteromed displacement of prox frac frag --> median n and brachial a injury
Intraventricular hemorrhage
Common complication of prematurity, occurs in infants <32 wks gestational age, sx: bulging ant fontanelle, hypotension, decerebrate posturing, coma. IVH originates from germinal matrix, a highly cellular and vascularized layer in subventricular zone --> thin walled vessels lacking support --> inc risk of IVH
Ulnar collat ligament injury
Common in throwers (e.g., baseball pitchers) due to intense valgus stress at elbow
Which nerve is susceptible to injury w/ prolonged lying during surg?
Common peroneal nerve at lateral neck of the fibula
Methylmalonic acidemia
Complete deficiency of methylmalonyl-CoA mutase. Cannot form succinyl-CoA to enter TCA cycle --> buildup of MMA and propionic acid --> high AG metabolic acidosis. Hypoglycemia, ketone production, hyperammonemia (organic acids inhibit urea cycle)
Management of bleeding
Compression of nasal alae, lean forward, silver nitrate cautery
Sudden-onset quadriparesis in pt w/ RA after urgent intubation
Compression of spinal cord due to vertebral malalignment/subluxation. RA involves atlantoaxial jt
Effect of prolonged NSAIDs on kidneys
Concentrate in renal medulla, cause chronic interstitial nephritis, tubular atrophy, and constriction of medullary vasa recta --> ischemic papillary necrosis
Bronchial hyperreactivity (methacholine challenge)
Concentration of inhaled methacholine required to produce a 20% decline in FEV1
Why does Weber lateralize to bad ear in conductive loss?
Conduction deficit (blocked sound) maksks ambient noise in the room, allowing the vibration to be better heard.
What error does matching in case control studies reduce?
Confounding
Thalamic syndrome
Contralat burning or stabbing pain over one side of body
Lissencephaly
Congenital absence of gyri. Severe mental retardation and sz, brain is smooth grossly
Triad of congenital rubella
Congenital cataracts (white pupils), sensorineural deafness, PDA
Hutchinson's incisors, mulberry molars
Congenital syphilis
Large, reducible abdominal protrusion in Down's
Congenital umbilical hernia (incomplete closure of umbilical ring, defect in linea alba)
3 most common causes of AS
Congenitally abnormal valve w/ calcification (bicuspid valve), calcified normal valve, rheumatic heart disease
Inflammatory response to lobar pneumonia
Congestion (day 0-2) - neutrophils respond to bacterial components, release cytokines, immune cell migration, abundant protinaceous fluid in alv space. Red hepatization (day 2-4) - protinaceous fluid transforms into fibrin strands, lobe appears liver like (red, firm, airless). Grey hepatization (day 4-7) - red cell disintegration, PMNs replaced by Mos that repair. Resolution (day 7) - Mos liquefy and phagocytose fibrinous exudate, lung parenchyma normal by 3 wks
Why does 23-valent toxoid pneumo vaccine reduce colonization rates?
Conjugation to recombinant, inactivated diphtheria toxin generates higher-affinity Abs and memory cells, creates mucosal Abs --> reduce colonization rates
Acute stroke in dorsolat thalamus
Contralat hemisensory loss, thalamic pain syndrome: excruciating pain on side of deficits wks to mos later
Unilat infarction of primary visual cortex in occipital lobe (PCA stroke)
Contralat homonymous hemianopsia with macular sparing (macula has collat circ from MCA). Conversely, MCA stroke leads to contralat sensory and motor deficits (upper > lower) and homonymous hemianopsia WITH MACULAR INVOLVEMENT)
What is the most common and persistent opioid s/e?
Constipation. Opioids are first-line tx for chronic cancer pain. There is tolerance to dosage and most s/e, but not to miosis or constipation. Pts on prolonged opioid therapy should receive proph bowel regimen (inc fluid intake, dietary fiber, laxatives)
Type IV hypersentivity (DTH)
Contact dermatitis, granulomatous inflam, +ve skin tests of TB, anergy (Candida Ag)
Caspases
Contain cysteine, able to cleave aspartic acid residues (cysteine-aspartic-acid-proteases). Initiator activate effector, which cleave cellular proteins
Transverse tubules
Contain voltage-gated LTCC (dihydropyridine receptors), allow the depol to rapidly propagate throughout muscle fiber --> synchronized contraction of myofibrils in each muscle cell
Xanthelasma is associated with what diseases?
Contains lipid-laden Mos, foam cells in superficial dermis. Obstructive biliary lesions, 1° biliary cirrhosis --> hypercholemia
Spread of infection to cavernous sinus thrombosis
Contiguous spread of infection from medial third of face, sinuses (ethmoidal/sphenoidal), teeth --> retrograde to cavernous sinus through valveless facial venous sys (via sup and inf ophthalmic vv). Damage to 3, 4, 5-1, (5-2), 6, proptosis and chemosis (conjunctival swelling) from impaired venous drainage thru ophthalmic vv
Heme lab findings in hereditary spherocytosis
Dec MCV (spherocytes are smaller due to membrane loss and red cell dehydration), inc MCHC (more intensely-staining cytoplasm)
Roux-en-Y gastric bypass
Create small gastric pouch removed from remainder of stomach and attached to jejunum via gastrojejunal anastomosis. SIBO characterized by excess Vit K and folate prod, and def in B12, ADE, iron, zinc
S/e of daptomycin
Creates transmemb chan that cause IC ion leakage and cell memb depol. S/e are myopathy and rhabdo
Acute lacunar stroke of ant pons
Corticospinal tract (contralat hemiparesis, Babinski sign), corticobulbar (contralat lower facial palsy, dysarthria), ataxic hemiparesis
Most important treatment to give to premature infant
Corticosteroids to mother (betamethasone, dexamethasone) to accelerate maturation of Type II pneumocytes --> inc surfactant prod. In infant, give exogenous surfacant
Lobar hemorrhages
Cortical branches of major cerebellar arteries, occur in older people w/ amyloid angiopathy, affect parietal and occipital lobe
Mucicarmine red round cells w/ narrow based buds
Cryptococcus
Budding yeasts
Cryptococcus (thick capsule) and Candida (w/ pseudohyphae) - they look similar! Germ tube test is diagnostic of C albicans, vs glabrata/tropicalis
Chronic lymphedema is a risk factor for what? E.g., after radical mastectomy w/ axillary LN dissection
Cutaneous angiosarcoma (Stewart-Treves syndrome). Infilitration of the dermis w/ slit-like abnormal vascular spaces.
Ecchymosis
Cutaneous or subQ collection of extravasated blood measuring at least 1 cm in diameter (non-blanchable b/c RBCs are not contained w/in the vasculature). Evolution of color change (blue or red to brown, green, and yellow) can be used to estimate age of injury
Cheyne-Stokes
Cyclic breathing pattern in which apnea is followed by gradually inc and dec tidal volumes until then next apneic period.
Cell cycle nonspecific chemo drug
Cyclophosphamide
Amifostine
Cytoprotective free-radical scanvenger used to dec nephrotox assoc w/ cisplatin, also dec dry mouth
Effect of chronic topical corticosteroids on skin biopsy
Dec prod of ECM Col and GAGs --> atrophy of dermis w/ loss of dermal Col, atrophic striae, drying and cracking of skin
Actions of leptin
Dec prod of NPY (potent appetite stimulant in arcuate nuc of hypo), and stim prod of POMC in arc nuc --> alpha-MSH inhibits food intake
Compensatory mechanisms in response to CHF (inc arteriolar resistance, inc PRA, inc ventricular EDP, inc SANS)
Dec renal perfusion --> inc RAAS --> vasoconstriction of arterioles, and inc arteriolar resistance --> more renin secreted due to drop in renal perfusion etc.
Presentations of sickle cell vasoocclusive crises
Dactylitis (children), pain crises, acute chest syndrome, leg ulceration, priapism, autosplenectomy (brownish discoloration, shrunken, fibrotic), stroke
Tx to prevent recurrence of genital HSV
Daily oral valacyclovir, acyclovir, or famciclovir. Continued for years w/ periodic reevaluation. Not active against latent virus forms, but suppress further multiplication upon reactivation
Arcuate scotoma
Damage to particular region of optic nerve head
Noise-induced hearing loss
Damage to stereociliated cells in the organ of Corti, loss of high-frequency hearing first. Cupula registers low-freq sound, ossicles affect air conduction across all frequencies
Drug that causes rhabdo
Daptomycin (elev CPK)
How is hepatic chol syn affected by statins and cholestyramine?
Dec (HMG-CoA reductase inhibitor, no chol syn) and inc (bile acid sequestration and dec enterohepatic circ leads to chol syn to make new bile acids)
Thrombotic thrombocytopenic purpura (erythrocytes sheared by platelet-rich thrombi)
Dec ADAMTS13 level --> uncleaved vWF multimers --> platelet trapping and activation. Sx: hemolytic anemia (inc LDH, dec Hp) w/ schistocytes, thrombocytopenia (inc bleeding time, normal PT/PTT), renal failure, neuro sx, fever. Management: plasma exchange, glucocorticoids, rituximab
Latanoprost
Dec Col content of uveoscleral outflow pathway and inc outflow of aqueous humor
Most common indicator of obesity related dz
Dec ERV and FRC
Emphysema
Dec FEV1/FVC ratio, inc TLC, dec DLCO (destruction of alveoli). Asthma has high DLCO b/c inc pulm cap blood vol
Signs of normal aging in heart
Dec LV chamber size, sigmoid shaped vent septum, inc interstitial CT, lipofuscin accum
Effect of nitrates on cardiac and vasc parameters
Dec LVEDP, inc periperhal venous capacitance, decreased SVR
Pathology of ectopic pregnancy
Decidualized endometrium only: dilated, coiled endometrial glands and vascularized edematous stroma
Therapeutic uses of Vitamin B6
Decrease adverse effects of isoniazid, and to dec homocysteine levels in homocystinuria (Marfanoid habitus, lens subluxation etc.)
Alcohol-induced hepatic steatosis
Decrease in FFA oxidation secondary to excess NADH prod by alcohol dehydrogenase and aldehyde dehydrogenase. Also inc peripheral fat catabolism, impaired lipoprot assembly
Pathophys of normal pressure communicating hydrocephalus
Decreased CSF resorption by arachnoid granulations (communicating hydrocephalus). May be due to idiopathy, 2° to MENINGEAL INFECTIONS LIKE TB or SAH --> scarring of arachnoid granulations. Ventricular enlargement out of prop to sulci enlargement
Effects of CKD on electrolytes
Decreased GFR --> decreased filtered phosphate load, elev serum PO4 levels. Hyperphosphatemia reduces serum free Ca, elev PO4 also reduces calcitriol syn
Effect of nutrient deficiencies and diabetic nephropathy on HbA1c
Decreased RBC turnover leading to increased HbA1c
Tabes dorsalis
Degen of DRG and dorsal columns
Mitral annular calcification
Degenerative calcific deposits in fibrous ring of mitral valve. Causes: women over 60, hx of myxomatous degen of valve, chronically elev LV pres
Receptor internalization/endocytosis
Desensitization of excessive NT stim, iron/transferrin receptor, chol/LDL-R
Vasopressin vs desmopressin
Desmopressin - selectively activates V2 receptors and does not cause vasoconstriction (mediated by V1 receptors)
Poliomyelitis and Werdnig-Hoffmann
Destruction of LMN in ant horn --> flaccid paralysis, muscle atrophy, fascic
Hemolytic disease of the newborn
Destruction of fetal RBCs by maternal Abs (IgG - crosses the placenta) directed against fetal RBC Ags. P/w positive direct Coombs test (autoimmune hemolysis), anemia, jaundice, generalized edema, persistent extramed hematopoiesis, release of immature nucleated erythrocytes
Pernicious anemia
Destruction of parietal cells in upper glandular layer of body and fundus (below simple columnar epith cells). Deeper are chief cells that secrete pepsinogen
POS plans
Similar to HMO, require pt to have PCP and require referrals for specialists. However, allow pt to see out-of-network providers. Have higher premiums than HMO
Presentation of somatostatinoma
Diabetes mellitus (diminished insulin secretion), cholelithiasis (inhibition of CCK release), diarrhea/steatorrhea (inhibition of panc enzymes/bicarb secretion)
Strongest risk factor for CAD
Diabetes mellitus, even in absence of other RFs for CAD. Also noncoronary atherosclerotic dz and CKD
Classic sign of lung hyperinflation on CXR
Diaphragm flattening
Presentation of large PDA complicated by Eisenmenger syndrome
Differential clubbing and cyanosis w/o BP or pulse discrepancy
CXR of hypersensitivity pneumonitis (inhalation of organic dusts)
Diffuse nodular interstitial infiltrates. Serum IgG Abs precipitate bacterial or fungal Ags in inhaled organic duct particles --> Type III hypersensitivity, immune complex deposition --> interstitial alveolitis and bronchiolitis
Scarlet fever
Diffuse, erythematous, "sandpaper"-textured rash in skin folds (inguinal, axillary, antecubital)
Medications that do not improve mortality in HFrEF
Digoxin (improves functional capacity and dec hospitalizations), diuretics (most effective at improving sx), CCB, nesiritide (BNP analog - vasodil and diuresis)
S/e of commonly used drugs in elderly
Digoxin ~ arrhythmias, N/V, confusion and weakness; 1st gen antihistamines and TCAs ~ cognitive decline, delirium, hallucination, orthostatic hypotension, falls, urinary retention, constipation; opioids ~ constipation, sedation, confusion, falls; antipsychotics ~ inc stroke and mortality, long-acting sulfonylureas ~ hypoglycemia, fluoroquinolones ~ tendon rupture
Hyperphenylalaninemia and elevated prolactin
Dihydrobiopterin reductase deficiency (BH4 needed for both phenylalanine --> Tyr and Tyr --> DOPA). In classic PKU, Tyr supplementation allows for dopamine prod, but not in BH2 reductase def
Dec hepatic N-acetyltransferase
Diminished ability to metabolize isoniazid and sulfonamides
Mechanism of diphtheria toxin, Shiga/EHEC toxin
Diphtheria - ribosylation of EF-2, Shiga - inactivation of 60S, pertussis - ribosylation of Gsalpha --> inc cAMP
Treatment of C diphtheriae infection
Diphtheria antitoxin (passive immunization), penicillin or erythromycin, DPT vaccine
Direct vs indirect inguinal hernias
Direct - pass thru superficial inguinal ring, not deep inguinal ring. Covered only by external spermatic fascia. Indirect - covered by all 3 spermatic fascial layers
Exceptions to verbal/written authorization requirement of HIPAA
Disclosure of serious communicable dz such as HIV or TB
Are distal or proximal pulm embolisms more likely to cause infarction
Distal PE - occlude areas distal to the pulm-bronchial anastomoses. More likely to be hemorrhagic (red infarct) than ischemic - lung tissue thin, lot of blood supply
Thin basement membrane dz
Disorder of Col IV that causes asxatic microscopic hematuria
Hamartomatous polyps
Disorganized mucosal glands, SM, CT. Can cause bleeding and intussusception
Pathogenesis of infective endocarditis
Disruption of normal endocardial surface --> focal adherence of fibrin and platelets (sterile fibrin-platelet nidus) --> microorg colonize sterile nidus
Daptomycin
Disrupts bacterial memb by creating transmemb chan --> IC ion leakage. Assoc w/ inc CPK and myopathy
Receptor binding of adrenergic agonists
Dobutamine (b1 > b2), dopamine (D1 > b1 > a1), epi (b1 = b2 > a1), norepi (b1 = a1 > b2), phenylephrine (a1)
Advantage of dobutamine over norepi and vice versa
Dobutamine causes positive inotropy and chronotropy, but also causes mild vasodil which is beneficial to reduce afterload (norepi causes vasoconstriction). However, vasodil is harmful in already-severely hypotensive pts
Global payment
Done for elective surgeries, insurer pays a provider a single payment to cover all expenses assoc w/ an incident of care
Pergolide
Dopamine agonist that directly stimulates D2 receptors.
Cabergoline
Dopamine agonist used in GH-secreting pit tumors or prolactinoma
Only adrenergic agonist that increases renal blood flow
Dopamine, D1 > b1 > a1 (low doses ~ stim D1-R in renal vasc and tubules, high doses ~ stim b1-AR, very high doses ~ stim a1-AR)
Anatomic snuffbox
Dorsoradial wrist, medially bound by EPL, laterally by APL and EPB
Dz that inc risk of ALL
Down syndrome, ataxia-telangectasia, NF1
D/o and CV defects
Down ~ regurgitant AV valves, ostium primum septal defects, DiGeorge ~ ToF, interrupted aortic arch, Friedreich ataxia ~ HOCM, tuberous sclerosis ~ valvular obstruction due to cardiac rhabdomyomas
Causes of methemoglobinemia
Drug exposures (e.g., dapsone, nitrites), enzyme deficiencies, hemoglobinopathies
S/e of isoniazid and presence of anti-histone Abs
Drug-induced SLE (DILE) - lacks cutaneous manifestations, patients w/ slow acetylator phenotype predisposed to develop DILE (can't inactivate drugs)
Breast tenderness and amenorrhea on risperidone
Drug-induced hyperprolactinemia. Inhibit D1/D2 --> inc prolactin --> inhibit GnRH
Wet vs dry beriberi
Dry - symmetric peripheral neuropathy of distal extremities. Wet - dry + cardiac involvement (cardiomyopathy, CHF, peripheral edema)
Autonomic sx of LEMS
Dry mouth, impotence. To differentiate MG and LEMS: LEMS have hyporeflexia or areflexia, autonomic sx, incremental response to stim
Vestibular neuritis (labyrinthitis)
Du to inflam of vestibular nerve (viral or postviral). Single episode that can last days, severe vertigo and N/V but no hearing loss
Why does lung not necrose in PE?
Dual circulation from pulmonary aa and bronchial aa. Pulmonary aa are major suppliers of blood to lungs, providing deoxy blood for gas exchange. Bronchial aa supply nutrients
Hydrocephalus ex-vacuo
Due to AD, AIDS dementia --> ventricular enlargement is proportional to sulci enlargement, thus due to generalized brain atrophy. Normal CSF pressure
Reflux esophagitis
Due to GERD, characterized by elongation of papillae, basal cell hypertrophy, intraepith eos --> repeated epith injury leads to Barrett's
Narcolepsy
Due to depletion of hypocretin-secreting neurons in the lateral hypothalamus (low hypocretin-1 levels in CSF)
Malignant hyperthermia
Due to halothane and succinylcholine --> abnormal ryanodine receptors release excess Ca during muscle contraction --> inc ATP use to sequester Ca --> ATP use gen heat
Testicular torsion
Due to indequate fixation of lower pole of testis to tunica vaginalis. Compression of pampiniform plexus --> reduced venous outflow. Acute, severe pain w/ NV, asymmetrically high-riding testis, absent cremasteric reflex
Treatment of Graves ophthalmopathy (proptosis)
Due to stimulation of orbital fibroblasts by anti-TSH-R Abs, leading to excess deposition of GAGs. Glucocorticoids have anti-inflam effects
Duodenal vs jejunal/ileal atresia (sx similar to midgut volvulus)
Duodenal - failure of recanalization at 8-10 wks gestation, Down syndrome. Jejunum/ileum - VASCULAR INJURY (ischemia --> stenosis/atresia), bilious emesis, gastroschisis. Colonic - unknown, constipation, Hirschsprung dz
Polio live attenuated oral vs IM inactivated vaccines
Duodenal luminal IgA differs most b/n them. Local secretory IgA prod stimulated by live oral vaccine (direct stim), and killed produces weaker immune responses
What part of the stomach does H pylori colonize?
Duodenal ulcer ~ Antrum, gastric ulcer ~ corpus
Lumbosacral plexopathy
During fetal descent, direct compression of lumbosacral trunk --> foot drop and numbness of lat aspect of leg and dorsum of foot, transient. Women have sx resolve w/in 1 yr
Why does BP change <10 mmHg normally on inspiration?
During inspiration, pres in pleural space/lung interstitium dec --> inc pulm vasc capacitance --> fall in venous inflow to heart --> dec LV SV and drop in systolic BP
Jugular foramen (Vernet) syndrome
Dysfcn of CN IX, X, and XI --> dysphagia, hoarseness, loss of gag reflex on ipsi side, deviation of uvula to normal side
Endometriosis involving the rectovaginal septum
Dyspareunia, dyschezia, palpable, tender nodularity. Pelvic pain and constipation around the time of menses
Westermark sign and Hampton hump in PE
Former - area of lucency due to reduced perfusion, latter - wedge-shaped opacity adjacent to pleura
Paradigm of porphyrin syn enzyme deficiencies
Early enzyme def - neurovisceral sx (acute porphyrias), later steps - (after condensation of PBG to HMB) result in photosensitivity (cutaneous porphyrias)
How to differentiate b/n early-onset post-MI pericarditis and Dressler's?
Early onset is localized to region of pericardium overlying the necrotic myocardial segment; Dressler's is diffuse inflam of entire pericardium
Two phases of asthma
Early phase - chemical mediators that cause immediate bronchial constriction, bronchial wall edema, inc mucus prod (allergen interaction w/ IgE), late phase - recruitment of additional inflam cells (eos, basophils, PMNs), bronchial obstruction
Electrolyte imbalance in CF
Eccrine sweat normally isotonic w/ ECF --> as it travels to skin surface, Cl resorbed via CFTR, Na and H2O follow --> facilitates prod of hypotonic sweat in nml pts. In CF, inability to resorb Cl and Na --> hyperNa, hyperCl sweat and hypoNa in body due to excesssive salt wasting
Tests to check before starting certain drugs
Echocardiogram ~ doxorubicin, FOBT ~ NSAIDS (PUD risk), PFTs ~ amiodarone, regular ophtho exams ~ hydroxychloroquine
Elastin (desmosine cross-links) vs collagen (disulfide bridges)
Elastin - rich in nonhydroxylated proline/glycine/lysine, requires lysyl oxidase (copper-dep) --> oxidative deamination of lysine residues of tropoelastin forms cross-links that give elastic properties
Markers of NTD
Elev AFP and AChE (both used in prenatal screening for NTDs)
Diagnostic features of glaucoma
Elev IOP, dec peripheral vision, inc cup to disc ratio
Homocystinuria (defect in Vit B6-dep cystathione synthase)
Elev homocystine, ectopia lentis, intellectual disability, Marfanoid habitus, inc thromboembolic events
Carcinoid tumors arise from which cell?
Enterochromaffin cells (endocrine) of intestine - 5-HT, bradykinin, PG --> metastasis to liver causes carcinoid syndrome. Extraintestinal carcinoids (bronchial carcinoid) can cause carcinoid syndrome w/o metastasis as they are secreted directly into systemic circ (bypassing hepatic metabolism)
CXR of NO2 (toxic prod of combusion, affects firefighters, welders)
Similar to asthma and COPD, pulm edema
Most common cause of coronary sinus dilation
Elevated R sided heart pressure 2° to pulm HTN (CS communicates freely w/ RA), also occurs in anomalous venous drainage to CS (persistent L SVC and TAPVR)
AV fistula effect on PV loops
Elongation of diastolic filling, inc LVEDV, dec TPR/afterload b/c arterioles are bypassed (direct from A to V). PE reveals pulsatile mass, thrill on palpation
Gower hemoglobin
Embryonic hemoglobin produced by fetus in utero in yolk sac (two zeta and two epsilon chains)
When should you listen to make S3 more audible?
End-expiration --> dec lung vol and brings heart closer to chest wall
Endoneural vs endomysial inflammatory infiltration
Endoneural - Guillan-Barre (ascending flaccid paralysis and hyporeflexia), endomysial - polymyositis. Dermatomyositis - perimysial/perifascicular
Pathogenesis of atheromas
Endothelial dysfunction attracts platelets --> locally adherent platelets and Mos release PDGF (promote migration of SMCs from media to intima and inc SMC prolif) and TGF-beta (chemotactic for SMCs and induces interstitial Col prod)
Steps in atherosclerosis
Endothelial injury/dysfcn causes inc vasc perm and enhanced leukocyte adhesion --> accum of LDL in vessel wall --> monocyte adhesion to endothelium, foam cells --> release of GFs by activated platelets/Mos --> recruitment of T cells and SMC prolif, ECM prod
Alzheimer's drugs
Enhanced cholinergic transmission (donepezil), neuroprotection via antioxidants (Vitamin E), NMDA receptor antagonism (memantine - CNS NMDA-R overstim by glut contributes to AD)
Pathology of molar pregnancy
Enlarged chorionic villi and avascular edematous stroma
CXR findings in 1° pulm HTN
Enlargement of pulm aa and RV
Stacked brick intestinal adhesion
Enteroaggregative E coli, persistent diarrhea in infants in developing countries
How does ethanol cause hypoglycemia?
Ethanol is metabolized by ALD --> inc NADH/NAD+ ratio --> all pathways requiring NAD+ are inhibited, incl GNG (no lactate to pyruvate, or malate to OA)
Transketolase
Enzyme of pentose phosphate pathway, converts ribulose-5-P to glyceraldehyde-3-P
Ependymoma
Ependymal perivascular pseudorosettes w/ GFAP positive processes tapering towards BVs
Ephelides vs solar lentigines
Ephelides - inc melanin prod, solar lentigo - inc # of melanocytes
Presentations of hematomas
Epidural hematoma ~ lucid interval followed by loss of consciousness, subdural ~ gradual onset of HA and confusion, SAH ~ severe thunderclap HA, fever, nuchal rigidity
Causes of brain hemorrhages
Epidural ~ middle meningeal a tear, subdural ~ bridging veins tear, SAH ~ ruptured saccular aneurysm
Actinic keratoses
Erythematous papules w/ overlying whitish scale, sandpaper-like texture --> may form cutaneous horns. Hyperkeratosis (hyperplasia of stratum corneum), parakeratosis (retention of nuc in stratum corneum), atypical keratinocytes w/ pleomorphic nuc and mult mitoses
Erythema marginatum
Erythematous, circular lesions with central clearing that come and go on trunk and extremities
Parvovirus B19 replicates in which cells?
Erythrocyte precursors in the bone marrow (cells that express blood group P-Ag/globoside, which is the cellular receptor for parvo)
Lab findings in multiple myeloma
Erythrocyte rouleaux formation on peripheral smear and Bence-Jones prot in urine
Bisphosphoglycerate mutase
Erythrocytes must gen energy via glycolysis b/c they lack mito for TCA. However, they can generate 2,3-BPG and sacrifice any ATP production --> imp regulator of O2-Hb binding in hypoxia and chronic anemia
Glycogen def of vaginal epith
Estrogen def from POF or menopause --> flattening of labial folds and vaginal rugae, dyspareunia
How do estrogens cause gallstones?
Estrogens inc biosyn of chol by upreg HMG-CoA reductase activity --> inc amt of chol secreted into bile
Increased activity of enzymes involved in cell wall polysaccharide syn
Ethambutol resistance
Mechanism of pulsus paradoxus
Exaggerated drop in BP during inspiration. During inspiration, VR increases --> fluid accum in pericardium prevents RV expansion --> interventricular septum bows into LV --> dec LVEDV and SV --> dec systolic pulse pres
Peyronie disease
Excess collagen formation in the tunica albuginea (covers corpora cavernosa and overlies testicles) causes pain and curvature of penis
EUVOLEMIC HYPONATREMIA IN SIADH
Excessive ADH secretion --> water retention, inc TBW, transient, subclinical ECFV expansion --> dec aldo and inc ANP/BNP --> inc urinary Na excretion, normalization of ECFV, further Na loss
Three most important factors for hypoglycemia in T1DM
Excessive insulin dose, inadequate food intake, physical activity/exercise. Pts taking exogenous insulin continue to release insulin from the injection site --> insulin release is not inhibited by a fall in glucose as it should be.
Causes of hyperNa
Excessive salt intake, free water loss (diarrhea, DI)
Viral recombination vs phenotypic mixing
Exchange of genes b/n 2 chrom via crossing over w/in homologous regions --> progeny have recombined genomes w/ traits from both parent viruses. Phenotypic mixing is trading of capsids w/ one another, but genome is unchanged and progeny don't retain new traits
Risk factors for hypoNa in CF
Exclusive breastfeeding or formula feeding prior to Na-rich food introduction, exposure to high temp, exercise. Tx: salt supplementation
Pulm HTN
Exertional dyspnea, fatigue, RV failure, inc intensity of P2 (pulmonic valve closure), no nocturnal dyspnea b/c LV is intact
SSSS (bullous impetigo is a more localized form)
Exfoliatin toxin (protease that cleaves desmoglein in desmosomes), +ve Nikolsky sign, epidermal necrolysis, fever, pain assoc w/ skin rash, affects only superficial epidermis
Anthracosis
Exogenous pigment endocytosis when urban-residing indiviudals inhale carbon or coal dust, uptaken by Mos in lung
Low serum thyroglobulin, thryotoxicosis, and small thyroid
Exogenous thyroid hormone use. Low thyroglobulin in serum --> noninflammatory suppression of thyroid activity, atrophy of thyroid follicles
Misclassification bias
Exposure or the outcome is not identified correctly. Random (nondifferential) ~ BP of two groups of adults measured using pediatric cuff --> both measurements are wrong, but misclassification affects both groups to same extent
Tropical sprue
Extended travel to tropics causes chronic D, abd pain, flatulence, villous atrophy. Infectious, treated w/ abx
Greater omentum
Extends from greater curvature of stomach to encompass transverse colon before reaching post abd wall. Contains gastrocolic lig (gr curvature to transverse colon). Divided during surg to access ant panc
Presentation of Pancoast (superior sulcus) tumor
Extensive smoking hx, hemoptysis, shoulder pain radiating towards axilla and scapula (involvement of lower brachial plexus - arm parasthesia, weakness, muscle atrophy), Horner syndrome, UE edema (compression of subclavian vessels), spinal cord compression
Otitis externa vs media
Externa - Ear pain and drainage, granulation tissue in ear canal, TM clear, no middle ear effusion. Media - inflamed, bulging, erythematous immotile TM (infected fluid in middle ear)
R sided brachiocephalic v obstruction
External compression by apical lung tumor, or thrombotic occlusion by central venous catheter. Sx: redness and edema, engorgement of subQ vv
Color of currant jelly sputum (Klebsiella) and rust-colored pneumo
Extravasation of RBCs and Hb into sputum
Spherocytosis is what kind of hemolysis?
Extravascular. Intravascular ~ destruction happening in vessels (prostethic valve, microangiopathic, PNH). Extravasc ~ no hemoglobinuria, Mo in spleen clear RBCs, spherocytes
Parapneumonic effusions in bacterial pneumonia
Exudative fluid accum w/in pleural space. LTB4 is chemotactic eicosanoid, other LTs are bronchoconstricting
Which med blocks intestinal chol absorption?
Ezetimibe
Immediate antidote for warfarin
FFP (Vit K takes time)
Failure of auditory volume modulation, sensitivity to everyday sounds
Facial nerve injury, which gives off the stapedial nerve to the stapedius. Tx of hyperacusis: retraining (sound) therapy using broadband noise/white noise
Which clotting factor has the shortest half life?
Factor VII. Clotting factors 2, 7, 9, and 10 are prod by liver in inactive form and require Vit K dep carboxylation. Unlike other factors, FVIII prod by endothelium
What does cryoprecipitate contain?
Factors VIII, XIII, vWF, and fibrinogen
25F w/ L renal agenesis and recurrent pregnancy loss
Failed lateral fusion of the paramesonephric ducts --> bicornate uterus (indentation in fundus), uterine didelphys. For recurrent preg loss, do HSG
Transverse vaginal septum
Failed vertical fusion of the paramesonephric ducts w/ the urogenital sinus. Sx: 1° amenorrhea, cyclic pelvic pain from hematometra (menses retained in uterus)
Tubulointerstitial nephritis
Failure of PCT to reabsorb LMW prots that are normally filtered by glom (b2-microglobulin, immunoglobulin light chains)
Lingual thyroid
Failure of migration of the thyroid leads to residence anywhere along the thyroglossal duct's path --> can lead to dysphagia, dysphonia
PKU (phenylalanine hydroxylase def)
Failure to convert phenylalanine to tyrosine --> intellectual disability
Selective mutism
Failure to speak in a specific social situation (school) but not in others. Assoc w/ anxiety, esp social phobia
Uses of lepirudin and argatroban, and dabigatran
First two - management of HIT, latter - stroke prevention in a-fib and DVT prevention
Conus medullaris syndrome (lesion at S2)
Flaccid paralysis of bladder and rectum, impotence, saddle (S3-5) anesthesia. Due to disc herniation, tumors, spinal fractures
Destruction of motor neurons in the ventral horns
Flaccid paralysis, atrophy of intrinsic muscles of hand, areflexia, fascic
Damage to cerv spinal cord
Flaccid quadriplegia, spinal shock (absence of flexor and extensor motor tone)
Flaccid bladder vs overactive bladder
Flaccid ~ LMN lesions (cauda equinal syndrome), large PVR. Overactive ~ UMN lesions (MS, loss of descending inhibitory cortical input), urge incontinence, no PVR
Path of CN V2
Foramen rotundum (skull to pterygopalatine fossa), then through IOF to appear on face at intraorbital foramen as the infraorbital nerve
Cholesterol granulomas
Form in middle ear after hemorrhage, bluish-black gelatinous mat'l behind the tympanic membrane
Attrition bias
Form of selection bias that results if the loss to follow up occurs disproportionately between the exposed and unexposed groups. Does not occur if losses happen randomly b/n groups
IVC at level of L4-5
Formed by union of R and L common iliac vv
Hereditary orotic aciduria vs ornithine transcarb def
Former - AR, physical and mental retardation (low ht/wt, delayed milestones), megaloblastic anemia, elev urinary orotic acid. Tx: uridine supplementation Latter - inc urinary orotic acid, no megaloblastic anemia, failure to thrive, hyperammonemia (and encephalopathy)
Wallerian degeneration (axon) vs axonal reaction (neuronal body)
Former - Degeneration distal to the point of injury. Swelling and irregularity distally, axon is destroyed w/in a week. Latter - cell body shows edema, nuc to periphery, granular dispersed Nissl substance (24-48 h after injury)
Activators and deactivators of 6-MP and 6-TG
Former - HGPRT, latter - xanthine oxidase and thiopurine methyltransferase, respectively. Reduce dose of 6-MP by 75% if pt is also on allopurinol
Misoprostol vs mifepristone
Former - PGE1 agonist, latter - prog and glucocorticoid antag
Schizoaffective d/o vs MDD w/ psychotic features
Former - Presence of delusions and/or hallucinations for >=2 wks in absence of major mood episode
Bicalutamide and danazol
Former - Testosterone receptor antagonist used in tx of prostate cancer, latter - synthetic steroid w/ androgenic and anti-estrogenic effects
Difference in Ca chan of cardiac/smooth vs skel muscle
Former - activation of LTCC --> influx of EC Ca, activates sarcoplasmic RyR --> CICR. Latter - LTCC in skel muscle directly interact w/ RyR Ca chan to release Ca from SR. Mechanical coupling allows SR release of Ca w/o sig Ca influx in skel muscle. Verapamil blocks LTCC, but skel muscle is not dep on EC Ca influx
FFP vs cryoprecipitate
Former - all coag factors, latter - cold-soluble proteins (FVIII, fibrinogen, vWF, vitronectin)
Tamoxifen vs raloxifen
Former - antiestrogenic at breast, stimulatory at endometrium --> endometrial hyperplasia. Raloxifen does not have this risk. Both are partial agonists at bone (inc BMD after menopause), dec LDL, ~HDL
Lead-time bias vs length-time bias
Former - apparent inc in survival time among screened pts b/c of earlier detection, not improved mortality. Latter - rapidly progressive form of disease is less likely to be detected than slowly progressive --> cancers detected by screening have a false increase in survival
Presentation of tuberculoid vs lepromatous leprosy
Former ~ least severe form, self limited, intact cell-mediated response, mild skin plaques w/ hypopigmentation and focally dec sensation. Latter ~ weak CMI, mycobacterial dissemination, diffuse skin thickening, plaque-like hypopigmentation, hair loss, leonine facies, paresis, regional anesthesia, blindness, testicular destruction
Tuberculoid vs lepromatous leprosy (leprosy assoc w/ armadillos)
Former: Positive lepromin test ~ cell mediated immunity (Th1) --> response of IL-2, IFN-g, IL-12, low bacterial load; latter: negative lepromin test ~ humoral immunity (Th2), high bacterial load
Where does gallstone ileus enter the gut, and where is it trapped?
Forms the fistula at the duodenum, is trapped at the ileocecal valve
Factors affecting resistance to fwd flow vs regurg flow in MR
Forward flow determined by pres in aorta (systolic BP), reg flow determined by mitral valve orifice size. Dec SVR inc ratio of fwd to regurg blood flow
24-hydroxylase
Found in kidneys, converts 25- and 1,25-OH2 to 24,25-OH2 Vit D (inactive)
Neurophysins
Found in secretory vesicles (carrier proteins for oxytocin and ADH), proteins that are involved in posttranslational hormone processing and stabiization during axonal transport
Effect of M2 receptors
Found on heart, lead to G-protein coupled dec in cAMP --> dec inotrophy and chronotropy
Fragility fracture
Frac due to a force sig less that that required to frac a normal bone
Fat embolism syndrome
Fractured bone releases lipid globules into pulm vasc
Bile acid formation
Free cholesterol converted into cholic and chenodeoxycholic acids thru rxns beginning w/ chol-7a-hydroxylase (RLS in bile acid syn) --> conj to glycine or taurine
K reabsorption in kidney
Free filtration in Bowman's space, 2/rds of K load is resorbed in PCT, 25-30% of filitered load at LoH (NKCC), regulation at CCD (hypoK --> 99% of filtered load resorbed, hyperK --> excreted > filtered)
Ecological study
Frequency of characteristic and outcome are studied using population data. Ecological fallacy: making conclusions regarding individuals w/in the pops studied
Vitamin E deficiency mimics what?
Friedrich ataxia --> ataxia, loss of position and vibratory sense, loss of DTRs. Occurs in pts w/ malabsorption or abetalipoproteinemia.
Ricin
From castor oil plant, potent toxin that cleaves rRNA component of eukaryotic 60S subunit
Brain regions supplied by MCA
Frontal, parietal, and temporal lobes, int capsule, basal ganglia. Ischemic stroke most common here
Methadone
Full mu receptor agonist, long half life, suppresses cravings and w/d sx for >= 24 h
Where does rotavirus replicate?
Fully differentiated intestinal epithelial cells
Conversion d/o
Functional neuro sx d/o, sx or deficits of voluntary motor/sensory fcn w/o neuro condition. Incompability (pt moves paralyzed limb moves when asked to move other limb), incongruous lack of concern about sx
Which murmur is often associated with pulm HTN?
Functional tricuspid regurgitation due to RV enlargement (2/6 holosystolic murmur at lower sternal border)
Arteriovenous nicking
Fundoscopic finding in pts w/ chronic hypertension, early manifestation of retinopathy
Initial tx of portal HTN
Furosemide and spironolactone combo w/ low-salt diet
Ras
G protein that regulates GF signal transduction. Particularly found in panc and CRC
Anemia, reticulocytosis, indirect hyperbilirubinemia, and low haptoglobin after taking antimalarial drug
G6PD (XR), hemolytic anemia due to med-induced oxidative stress
Mechanism of hepatic encephalopathy after GI bleed. Pathophys: inability of liver to convert ammonia (neurotoxin, can cross BBB) into urea; also inc GABA, dec glutamate --> AMS
GI bleeding causes inc nitrogen delivery to the gut in the form of Hb --> converted into ammonia by gut bacteria and absorbed into bloodstream. Cirrhosis is assoc w/ low serum BUN b/c ammonia cannot be converted into urea by the failing liver
Which transporter absorbs fructose?
GLUT5 (five = fructose), insulin-independent transporter
GAS GN vs ARF
GN assoc w/ prior strep pharyngeal or skin infection (impetigo), ARF assoc w/ prior strep pharyngitis but not skin infection
IP3
GOAT HAG (GnRH, oxytocin, ADH, TRH, histamine (H1-R), AII, gastrin
Introns end sequences that spliceosomes look for
GU at 5' splice site, and AG at the 3' splice site
Acute cerebellar vermis damage
Gait and truncal ataxia. Vermis connects to medial descending motor systems
Somatostatinoma sx
Gallbladder stones (poor gallbladder contractility - CCK), hyperglycemia (insulin), steatorrhea (secretin), hypochlorhydria (gastrin), dec GH secretion
Mirizzi syndrome
Gallstone becomes impacted in the cystic duct or neck of the gallbladder causing compression of the common bile duct or common hepatic duct
S bovis
Gamma hemolytic, catalase-negative, colon cancer
Which cell jcn is imp to coordinate contractions in labor?
Gap jcns. Connexons made of 6 connexin proteins. Estrogen upreg gap jcns b/n myometrial SMCs
Cell jcns and their proteins
Gap ~ connexons, tight ~ claudins/occludins, adherens (actin) ~ cadherins, desmosomes (intermed filament) ~ cadherins (desmogleins, desmoplakins), hemidesmosomes ~ integrins
Gastric ulcers vs duodenal ulcers
Gastric ulcers - colonization of gastric corpus/body, not acid related, due to direct mucosal damage, worsens w/ eating. Duodenal - dec SMS, inc gastrin, excess acid, improves w/ eating
Pt w/ hepatosplenomegaly, pancytopenia, osteoporosis, "wrinkled tissue paper" cells
Gaucher dz. Charaterized by lipid-laden Mo (wrinkled tissue paper, wrinkled silk, crumpled newspaper)
Muts affecting cardiac cytoskel prots or mito enzymes of ox phos
Genetic form of DCM
Characteristics of anaplastic tumors
Giant, multinuc tumor cells, loss of cell polarity w/ disruption of cell architecture, variation in size and shape of cells and nuc, high N:C ratio, hyperchromatic, numerous mitotic figures
Phenotypes of 21-OH def
Girls present at birth w/ ambiguous genitalia for severe and moderate, may only have acne, hirsutism and menstrual irreg for mild. Severe in boys present at 1-2 wks w/ salt wasting, moderate (non-salt wasting) present at 2-4 yrs w/ early virilization
How does the vaccine for pregnant women against neonatal tetanus work?
Give inactivated tetanus toxin (tetanus toxoid) --> vaccinated women give transplacental IgG to fetus, dec incidence of neonatal tetanus by 95%. DO NOT VACCINATE the neonate b/c of immature immune sys - first dose of TDaP at 2 mo of age
Gs proteins
Glucagon, TSH, and PTH
Causes of myopathy
Glucocorticoid induced: prog prox muscle weakness and atrophy w/o pain, normal CK. PMR: muscle pain and stiffness in shoulder, neck, pelvic girdle, normal CK. Hypothyroid myopathy: prox weakness, pain and cramps, DTR, elev CK
What is used to treat acute gout in pt w/ CI for NSAIDs and colchicine?
Glucocorticoids. Use colchicine in pt w/ gout and PUD
Polyol pathway
Glucose --> (aldolase reductase, NADPH) --> sorbitol --> (sorbitol dehydrogenase, NAD+) --> fructose. Sorbitol cannot cross cell memb and is trapped in cells where it forms; inc cellular osmotic and oxidative stress --> diabetic complications
Effect of glucose on lac operon
Glucose dec activity of AC and thus dec cAMP --> low cAMP prevents binding of CAP to upstream site --> repression of lac operon
MOA of sulfonylureas
Glucose enters cells via GLUT2, undergoes ox metabolism to ATP --> high ATP/ADP ratio triggers ATP-sensitive K chan closure, memb depol --> inc IC Ca, insulin release
What step of pentose phosphate pathway does G6PD catalyze?
Glucose-6-phosphate --> ribulose-5-P + 2 NADPH
Glutamate-glutamine cycle
Glutamate binds nitrogen in astrocytes to make glutamine, which is taken up by neurons and converted back to glut --> prevents excessive neuronal excitation. Excess ammonia in blood crosses BBB, taken up by astrocytes --> inc glutamine prod, excess osmolarity in astrocyte --> swelling, impaired glutamine release --> disruption of excitatory neurotransmission
NMDA agonists
Glutamate, aspartate, D-cycloserine
What is the most abundant AA in collagen?
Glycine (think glycine-X-Y)
What happens in cytosol?
Glycolysis, fatty acid synthesis, pentose phosphate pathway
Antiandrogen therapy
GnRH agonists (leuprolide) ~ inhibit LH release from ant pit, ketoconazole ~ prevents T syn in Leydig cells, 5-AR inhibitors (finasteride) ~ prevent T --> DHT conversion in peripheral tissues, flutamide/cyproterone/spironolactone ~ prevent androgen receptor-binding at target organ
McCune-Albright syndrome
GnRH-indep precocious puberty, polyostotic fibrous dysplasia, café au lait spots (stim of melanocytes by Gsalpha activating mut)
Why is levo/carbidopa used as late as possible?
Goal is to delay introduction of levodopa for mos to yrs to delay levodopa-related side effects
How to distinguish lupus and dermatomyositis hand findings?
Gottron's papules - DM, on top of jts. Lupus - rash between interphalangeal jts. Also, DM has heliotrope rash, SLE has butterfly/malar rash (sparing nasolabial folds)
Tall columnar follicular epithelium w/ scalloped margins of colloid
Graves disease, hyperactive reabsorption of colloid, high serum thyroglobulin levels. Tall cell variant of papillary thyroid cancer ~ follicular hyperplasia w/ elongated epith cells
Hyperacute graft rejection
Gross mottling and cyanosis, arterial fibrinoid necrosis and capillary thrombotic occlusion, neutrophil infiltration of arterioles, glom, peritub caps
Why does leprae appear on skin, superficial nerves, eyes, testes?
Grows best at temps below core body temp. Affects Schwann cells
Adenocarcinoma in situ (of lung), i.e. bronchioalveolar carcinoma
Growth along intact alv septa w/ vasc or stromal invasion, well-differentiated, dysplastic columnar cells. Can prod copious amounts of watery sputum (bronchorrhea)
RTK
Growth factors (IGF-1, FGF, PGDF, EGF, insulin)
S/e of epleronone and spironolactone
Gynecomastia
Satellite phenomenon
H flu type b grow on plates streaked w/ Staph aureus, b/c latter actively secrete NAD+ into medium
What is the best way to dx tetanus?
H&P. Culture may take several days, tetanus is only found locally at inoculation site, no serum toxin assay for tetanospasmin, no Ab test available. Booster immuniz recommended every 10 yrs
DS DNA --> +RNA template --> dsDNA progeny
HBV
Transmission of HBV vs HCV
HBV - sexual/parenteral/vertical, HCV - IVDU
Importance of Hep B Ags and Abs
HBeAg - indicates high transmissibility. Anti-HbC - acute/recent infection, most specific marker for dx of acute HepB
High infectivity chronic Hep B to low infectivity
HBeAg seroconversion: low infectivity state is characterized by detection of HBsAg and anti-Hbe in the absence of HBeAg
Mediator of hepatocyte damage in Hep B
HBsAg and HBcAg expression on hepatocyte cell surface --> CD8 T lymphocytes destroy infected cells. HBV has no cytopathic effect. Integrative phase - liver damage tapers off b/c infectivity ceases, but inc risk of HCC from HBV DNA integration into host genome
Liver mass assoc w/ inc AFP
HCC, trigger of neoplastic changes is integration of HBV viral DNA into host genome
Risk factors for HCC
HCV, alcoholic cirrhosis, aflatoxins, hemochromatosis
Homocystinuria pathways
Homocystine --> methionine via methinione synthase (uses B12). Homocysteine --> cystathionine by cystathionine synthase (uses B6)
Contraindications to nitrate use
HOCM (due to inc outflow tract obstruction), RV infarction (due to reduction in preload, impairing CO), and on PDE-I (synergism causes hypotension)
Bifid carotid pulse w/ brisk upstroke ("spike and dome")
HOCM (dynamic LVOT obstruction during systole)
Systolic ant motion of the mitral valve
HOCM, eccentric MR and exacerbation of LVOT --> systolic murmurs (after S1 and before S2)
Associations w/ Friedreich ataxia
HOCM, kyphoscoliosis, pes cavus, hammer toes, DM
Muts in cardiac cell sarcomere prots (beta-myosin heavy chain)
HOCM. Also mutations in myosin-binding protein C
Anal SCC
HPV 16 and 18
DKA and TG breakdown into gluconeogenic substrates
HSL breaks TG into FFA and glycerol in response to low insulin --> transported to liver and acted upon by glycerol kinase --> DHAP to be used in GNG
9F w/ 3-min generalized sz, dies overnight, temporal lobe necrosis
HSV-1 encephalitis
Why does HTN cause aortic dissection
HTN --> medial hypertrophy of aortic vasa vasorum --> reduced blood flow to aortic media --> medial degen w/ loss of SMCs, aortic enlargement and inc wall stiffness --> inc risk of intimal tearing
Which inhaled anesthetics can cause acute hepatitis?
Halogenated inhaled anesthetics (halothane, enflurane, isoflurane, sevoflurane) --> metabolized by hepatic CYP450, converts them into reactive intermediates that damage liver
Short term tx of agitation in delirium
Haloperidol (high potency first gen antipsychotic). Benzos worsen delirium and are only used for tx of delirium due to etoh or benzo w/d
Meiosis
Halts in prophase I until puberty, halts in metaphase II until fertilization
RVOT obstruction in ToF (pulmonic stenosis) murmur
Harsh SEM over mid to left upper sternal border. Squatting inc afterload and dec R to L shunting, thus improving cyanosis
Extensive lymphocytic infiltrate of thyroid w/ germinal center formation
Hashimoto thyroiditis. Residual follicles surrounded by Hurthle cells (large oxyphilic cells filled w/ granular cytoplasm), undergone metaplastic change in response to inflam
Heteroplasmy
Having different mito genomes w/in a single cell (every cell has hundreds of mitos) --> severity of mito dz is directly related to prop of abnormal to normal mito w/in a pt's cells
HbS vs HbC
HbS has E6V (nonpolar residue on outside --> promotes hydrophobic aggregation and sickling), HbC replaces polar w/ polar
Cystathionine synthase deficiency
Homocystinuria (AR, marfanoid body habitus, hypercoag), B6 dependent
Sx of large, unrepaired PDA
Heart failure (SOB, fatigue), cyanosis (Eisenmenger), clubbing in LE b/c PDA delivers unoxygenated blood distal to L subclavian
What enzyme gives bruises their green color in their evolution?
Heme oxygenase (contained in Mo) degrades heme into biliverdin, CO, and ferrous iron --> biliverdin reduced to yellow pigment bilirubin by biliverdin reductase
What happens in both mito and cytosol?
Heme synthesis, urea cycle, gluconeogenesis
Subclavian steal
Hemodynamically sig stenosis of subclavian a --> steals from contralat vertebral a to ipsilat vert a. Sx are arm ischemia (pain, exercise-induced fatigue), vertebrobasilar insuff (dizziness, vertigo, drop attacks)
Vitamin E deficiency
Hemolytic anemia and neurologic abnormalities (e.g., ataxia). Vitamin E needed to protect FAs from oxidation; neurons w/ long axons have large memb SA, and erythrocytes have high O2 exposure
Chancroid
Hemophilus ducreyi - deep, purulent, painful ulcers with matted/suppurative lymphadenitis
HSV encephalitis
Hemorrhagic lymphocytic pleocytosis on CSF w/ inc prot and normal glucose, bilat temp lobes have abnormal MRI signal
Complication of PNH
Hemosiderosis (iron deposition in kidney due to chronic hemolysis)
Substances found in basophil granules
Heparin, histamine, SRS-A (slow-reacting substance of anaphylaxis)
Structures that lie in the lesser omentum
Hepatic a, common bile duct, portal v, lymphatics, hepatic plexus, R and L gastric aa and gastric vv
Which liver mass can regress w/ discont of OCPs?
Hepatic adenomas
Vitamin A toxicity
Hepatic enlargement and toxicity, dry skin, pseudotumor cerebri, blurry vision
Polyarteritis nodosa (spares the lungs) assoc w/ which dz
Hepatitis B
Fulminant hepatitis in pregnant women in Asia/Mexico
Hepatitis E
Sx of liver dz in A1AT def
Hepatosplenomegaly, hepatomegaly, cholestasis, elevated transaminases, mild thrombocytopenia. Neonatal hepatitis w/ cholestatic jaundice is common, attacks of hepatitis childhood appear to complete resolve
What differentiates Tay Sachs and Niemann Pick?
Hepatosplenomegaly. Both have neurologic regression and cherry-red macular spots
Anemia, elev LDH, indirect hyperbili, +ve acidified glycerol lysis test, -ve Coombs (+ve Coombs w/ all other sx same suggests AIHA)
Hereditary spherocytosis. Glycerol lysis test: lysing of blood cells when incubated in hypotonic saline. Mut in spectrin/ankryin, can get jaundice and splenomegaly, pigmented gallstones
Contents of Meckel diverticulum
Heterotopy/ectopy: Contains ectopic tissues (gastric, pancreatic, colonic, jejunal, duodenal, endometrial). Mucosa, submucosa, muscularis, ectopic gastric epithelium (secretes acid and ulcerates adjacent mucosa --> melena/hematochezia)
Stimulators of inc K excretion
High EC K levels, inc aldo, alkalosis, inc fluid flow (volume expansion, high Na intake, diuretic use (thiazide and loop) --> flush away secreted K, inc gradient)
CIN in context of HPV (low grade CIN regress spont!)
High grade CIN - atypical cells have invaded beyond lower 1/3rd of cerv epithelium up to epithelial surface --> high rate of progression to cancer. Low grade CIN - cells below 1/3rd of cerv epith --> most LSILs regress spont
Properties of drugs w/ high intrinsic hepatic clearance
High lipophilicity, high Vd. In kidney, highly lipophilic drugs cross back into tissues after filtration. Low Vd drug is highly plasma prot bound and hydrophilic, will not enter hepatic cell and will be filtered in kidney
Aw resistance along the bronchial tree
High resistance in trachea, highest in medium sized bronchi (turbulent flow), dec exponentially to minimum in term bronchioles (greatest total cross-sectional area)
Anal carcinoma
High risk HPV (HPV 16 and 18)
Vesicoureteral reflux
High risk of chronic pyelonephritis, occurs at upper and lower poles of kidney where compound papillae are found, loss of nephrons --> 2° HTN
How to distinguish pit adenoma from ectopic ACTH prod (SCLC)?
High-dose dex suppression test. Pit sources of ACTH are only somewhat resistant to feedback inhibition --> high dose dex will dec cortisol. Ectopic ACTH is not under feedback regulation
Pertussis (even occurs in IMMUNIZED adults who have not had vaccination boosters)
Highly contagious, acute tracheobronchitis, transmitted by resp droplets, CXR NORMAL (no pulm consolidation). Catarrhal phase - like mild URTI (malaise, mild fever, rhinorrhea), paroxysmal phase - severe coughing spells w/ classic inspiratory whoop or post-tussive emesis, convalescent - cough improves
First region to be damaged in AD
Hippocampus - anterograde amnesia
Small ovoid bodies within a macrophage
Histoplasma capsulatum. Sx of disseminated histoplasmosis in AIDS pt are hepatosplenomegaly, lymphadenopathy, ulcerated lesions on tongue
Functional MR
Holosystolic murmur over cardiac apex due to hemodynamic factors causing LV dilatation and papillary muscle ischemia, instead of fixed mitral valve lesion
Medulloblastoma
Homer-Wright rosettes, small blue cells that may surround neuropil, cerebellar tumors
Acute graft rejection
Humoral: C4d deposition, neutrophilic infiltrate, nec vasculitis. Cellular: Dense interstitial mononuc/lymphocytic infiltrate
Croup
Hx of recent URI, brassy, barking cough, dyspnea from inflamed subglottic tissue obstructing upper aw
Allergic bronchopulmonary aspergillosis (Aspergillus only causes infections in immunocompromised pts, but it can colonize the bronchial mucosa and asthma/CF pts develop an allergic hypersensitivity rxn to the fungus)
Hx: asthma (ABPA in 5-10% of corticosteroid-dep asthmatics), CF. Chest imaging: recurrent fleeting infiltrates, bronchiectasis (on CT scan). Dx: eosinophilia, +ve skin test for Aspergillus, +ve Aspergillus-specific IgG, elev Aspergillus-specific and total IgE
Renal biopsy w/ eosinophilic hyaline mat'l in intima and media of small arteries and arterioles
Hyaline arteriolosclerosis, seen in poorly controlled HTN or DM. Repetitive endothelial injury caused by hemodynamic stress or hyperglycemia --> leakage of plasma constituents across vasc endoth, stim SMC prolif and excessive ECM prod
Which are high-risk drugs for DILE?
Hydralazine, procainamide, isoniazid, D-penicillamine. Slow acetylators are at greatest risk for DILE (procainamide metabolized by hepatic acetylation)
Protein catabolism
Hydrolysis of PPs into AAs --> transamination into predominantly glutamate --> oxidatively deaminated to produce ammonia
Ion channel myopathy
Hyper and hypokalemic periodic paralysis - episodic, painless muscle weakness
Stages of graft rejection
Hyperacute - acute cessation of blood flow (preformed Abs in recipient against donor), acute - dense mononuc infiltrate w/ T lymphocytes, chronic - scant inflam cells and interstitial fibrosis (mediated by host B/T lymphocytes and Abs)
Morphology of transplant rejection rxns
Hyperacute - gross mottling and cyanosis, arterial fibrinoid necrosis and cap thrombotic occlusion. Acute - C4d deposition, neutrophilic infiltrate, nec vasculitis, lymphocytic interstitial infiltrate and endotheliitis. Chronic - vasc wall thickening, luminal narrowing, interstitial fibrosis, parenchymal atrophy
Risk factors for nephrolithiasis
Hypercalcuria, hyperoxaluria, hypocitraturia, hyperuricosuria, low intake of Ca, high oxalate intake (spinach/rhubarb), dehydration. CITRATE BINDS UP OXALATE IN URINE --> LESS STONES
Folic acid deficiency
Hyperhomocysteinemia - prothrombotic state
Oxygen toxicity
Hyperoxia inc prod of ROS, leading to injury of aws and lung parenchyma. Substernal heaviness, pleuritic chest pain, cough/SOB after 24 h of breathing pure O2
Seborrheic keratosis
Hyperpigmented lesion, well-circumscribed borders, stuck-on appearance. Hyperkeratosis, keratin-containing cysts
Onion-like concentric thickening of arteriolar walls
Hyperplastic arteriolosclerosis seen in malignant hypertension (diastolic pressure >120-130 mmHg)
Perivascular infiltrate with abundant eos
Hypersensitivity myocarditis (initiation of a new drug therapy, body mounts atopic response)
Rheumatoid arteritis
Hypersensitivity vasculitis affecting arterioles and aa, produces visceral infarctions after long-standing RA
Diastolic dysfcn is seen in which heart dz
Hypertensive heart dz, restrictive cardiomyopathy, severe AS, hypertrophic cardiomyopathy
Hyperplastic arteriolar changes (intimal fibroelastosis)
Hypertensive nephropathy in pts w/ poorly controlled HTN
Drug induced ANCA Abs-assoc vasculitis
Hyperthyroidism meds (PTU, methimazole), hydralazine
Cardiogenic shock and watershed necrosis
Hypoxic-ischemic encephalopathy. Watershed zones = bilat wedge-shaped strips of necrosis on cerebral convexity, parallel to and few cm lat to longitudinal cerebral fissure
Sarcomere protein mutations
Hypertrophic cardiomyopathy and familial dilated cardiomyopathy
Trochlear nerve palsy
Hypertropia and extorsion, chin tuck and head tilt to compensate. Majority are traumatic or idiopathic (microvasc nerve ischemia 2° to DM), vertical diplopia in up-close reading and walking down stairs
Hypospadias vs epispadias
Hypo - incomplete fusion of urethral folds, epi - faulty positioning of genital tubercle in 5th week
S/e of amphotericin B
HypoK and hypoMg, dec EPO prod (normochromic, normocytic anemia)
Failure of third and fourth pharyngeal pouches
Hypocalcemia and T cell deficiency
Which nerve can be stimulated to reduce OSA sx?
Hypoglossal nerve stimulator - moves tongue forward slightly, inc AP diam of aw
Differentiate Cori from other glycogen storage dz
Hypoglycemia, ketoacidosis, hepatomegaly, muscle weakness, hypotonia, hepatic fibrosis, glycogen w/ abnormally short outer chains (limit dextrins). Hepatic steatosis is classic for von Gierke
Feared complication of ATN (in recovery phase)
Hypokalemia (due to large-volume diuresis after previous oliguria and slowly recovering tubular fcn). Recovery phase lasts 1-2 wks. Maintenance phase: low urine Osms, high urine Na, high FENa
Pierre-Robin sequence
Hypoplasia of mandibular prominence --> severe micrognathia, post displacement of tongue
Aortocaval compression syndrome/supine hypotension syndrome
Hypotension, pallor, sweating, nausea, dizziness when pregnant woman lies supine. >20 wks gestation, obstruction of IVC. Tx: L lateral recumbent position
S/e of lithium therapy for bipolar
Hypothyroidism and nephrogenic DI
Chiari I vs II
I - benign, common, low-lying cerebellar tonsils extending into vert canal. In adolescence p/w paroxysmal occipital HA due to meningeal irritation and dizziness/ataxia from cerebellar compression. II - severe, non-comm hydrocephalus from aqueductal stenosis, medulla compression --> dysphagia, stridor. Lumbar myelomeningocele --> lower limb paralysis
Why do gigantism pts grow tall but precocious puberty don't?
IGF-1 does not close the epiphyseal plates, but estrogen does. Both cause growth
Which IL is responsible for B cell growth and isotype switching?
IL-4
Extraarticular manifestations of RA
ILD/IPF (honeycombing), Caplan syndrome, rheumatoid nodules in lung, Felty syndrome (neutropenia and splenomegaly), Sjogren
Correction of hypoglycemic shock when IV glucose not available
IM or subQ glucagon injection
Which artery traps horseshoe kidney?
IMA
Urethritis vs cystitis vs acute pyelonephritis
IMPORTANT: While pyuria and bacteriuria are found in LUTI, WBC CASTS are pathognomonic for pyelo (formed in tubules by Tamm-Horsfall prot , renal origin of pyuria). Both urethritis and cystitis ~ dysuria, frequency, urgency, pyuria, bacteriuria. Cystitis only ~ suprapubic pres, tenderness. Acute pyelo ~ fever, chills, N/V, flank/abd pain, CVA tenderness
Dec activity of bacterial catalase-peroxidase
INH resistance
Functions of IP3
IP3 releases IC Ca and also activates PKC
Initial treatment of status epilepticus
IV benzo, AND IV phenytoin (long-acting, concurrent, to prevent recurrence of sz activity)
Shape of oxygen dissociation curve of single hemoglobin unit
Identical to myoglobin, hyperbolic, no cooperativity
Constrictive pericarditis
Idiopathic or viral, radiation therapy, TB. Limits ventricular expansion during diastolic filling. Signs incl inc JVP, Kussmaul sign, pulsus paradoxus, pericardial knock
Which proteins are deposited in HSP?
IgA and C3. Triad of palpable purpura on buttocks/legs (skin), arthralgias (large jts of LE), abd pain (assoc w/ intussusception)
RPGN deposits
IgG and C3. Anti-GBM Abs may cross react w/ Col IV in pulm alv BM --> pulm hemorrhage (Goodpasture)
Which molecules are deposited in PSGN?
IgG, IgM, and C3
Which blood antibodies are capable of crossing the placenta and causing HDN?
IgG. Type O genotype produce anti-A and anti-B IgG, whereas Type A produce anti-B IgM, and Type B produce anti-A IgM
Is IgM or IgG more efficient at initiating classical C cascade?
IgM - circulates as pentamer, allows for inc C interaction
Meckel diverticulum
Ileal outgrowth resulting from failed obliteration of the vitelline duct. Sxatic pts have spont but painless lower GI bleeding. Lead pt for intussusception, colicky abd pain and currant jerry stools
Most common site of intussusception
Ileocolic jcn (size diff in adjacent segments allow small bowel to invaginate into cecum). Colicky, intermittent abd pain, N/V, currant jelly stools
What landmark is used when doing an LP?
Iliac crests ~ L4 verebral body. LP done at L3/4 or L4/5 space.
Nerve damaged during appendectomy, suprapubic sens loss
Iliohypogastric
What does the inguinal canal contain?
Ilioinguinal nerve, round ligament (women), spermatic cord (men). Men are more susceptible to inguinal hernias due to their larger deeper inguinal ring
Tx of varicella postexposure prophylaxis in neonates or pregnant women
Immunoglobulin therapy
Causes of polyhydramnios
Impaired fetal swallowing (ancephaly - think epilepsy drug ADR, fetal GI obstruction) or increased fetal urination (high fetal CO from parvovirus). Causes uterine enlargement greater than gest age. Complications: preterm labor, placental abruption, uterine atony/overdistension, risk of maternal resp compromise
Myasthenia gravis
Impaired functioning of nAChR at NMJ due to interference by IgG Abs. Ice pack dec temp --> AChE activity dec, improves sx (ptosis)
Cystinuria
Impaired renal cysteine transport. Sx: flank pain, hematuria, renal stones in childhood
Flesh-colored nodules/powder burn patterns/adhesive dz in pelvis and abdomen
Implants of endometriosis
Elev plasma homocysteine
Independent risk factor for thrombosis (DVT, CAD, stroke). Due to direct and indirect endothelial damage
SLE vs DILE
In SLE, anti-dsDNA Abs are seen in 80%; anti-histone Abs in only 50%. In DILE, anti-histone Abs very common; anti-dsDNA Abs are rare
Serum Na in central DI, nephrogenic DI, 1° polydipsia
In first two, serum Na is high b/c of free water loss. In 1° polydipsia, serum Na is low due to excess water intake and inability of kidneys to excrete such a large quantity of water (50 mOsm/L minimum)
Processing of hnRNA to mRNA
In the nucleus: 5'-capping, poly-A tail addition, intron splicing. In cytoplasm, mRNA quality control at, and storage in, cytoplasmic processing bodies (P-bodies), contain exonuc, decapping enzymes, microRNAs
Activation-induced T-lymphocyte cell death
In the presence of stimulating self-Ags, activated T lymphocytes undergo apoptosis. Mutations in Fas/FasL cause autoimmune dz (e.g., SLE)
Which gene is involved in familial PPAH?
Inactivating mutations in BMPR2 (pro-apoptotic)
Mechanism of resistance to aminoglycosides
Inactivation by aminoglycoside-modifying enzymes
Diffuse esophageal spasm
Inappropriate contraction of several segments of esophagus, non-peristaltic contractions, "corkscrew" esophagus, impaired inhibitory neurotransmission in esophageal myenteric plexus
Sx of cannabis use
Inappropriate laughter, sedation, slowed reflexes, cognitive impairment, conjunctival injection, tachycardia, "munchies", dry mouth. Metabolized by liver, stored in lipophilic tissues, slowly released
Compression atrophy
Inc ICP or mass lesion; dec in size and # of neurons
Maternal serum AFP screening
Inc MSAFP: open neural tube defects, ventral wall defects (omphalocele, gastroschisis), multiple gestation. Dec MSAFP: aneuploides (trisomy 18/21)
Lung volume changes w/ aging
Inc RV (inc lung compliance due to dec ER and dilation of alv ducts), ~TLC (dec CW elasticity counters inc in lung compliance)
Things that diminish HCM murmur
Inc afterload (sustained hand grip), inc afterload and preload (standing to squatting), passive leg raise (inc preload)
Endometrial carcinoma in PCOS
Inc androgen --> prevents development of monthly dominant follicle --> anovulatory cycles, dec progesterone --> inc E/P ratio, endometrial hyperplasia
Morphologic findings of pulmonary HTN
Inc arteriolar SM thickness (medial hypertrophy), intimal fibrosis, sig luminal narrowing. In severe HTN, form plexiform lesions
Factors promoting cholesterol stone formation
Inc chol, dec bile acids, dec phospholipids
Hypercalcemia of Hodgkin's and granulomatous dz (sarcoid)
Inc conversion of 25-OH Vit D to 1,25-OH2 Vit D (active form) by 1alpha-hydroxylase produced by granuloma.
Sequelae of CREST and systemic sclerosis
Inc prolif and accum of monoclonal T cells --> TGF-beta secretion, excess Col deposition --> PAH
Pathogenesis of pulm HTN in L sided HF
Inc pulm venous congestion --> endothelial damage and leakage of serum prots into interstitium --> dec NO and inc endothelin-1 prod --> inc vasc tone, inc SMC prolif, Col deposition
Cytogenetic appearance of fragile X
Inc repeats don't stain in folate deficient medium --> small "gap" near tip of X chrom
W/u of pt w/ 1 testicle of any age
Inc risk of cancer, so "abdominal testicles" are removed (orchiectomy) or surgery to allow descent into scrotum (orchiopexy)
Inhibition of 7-alpha-hydroxylase (fibrates)
Inc risk of cholesterol stones by reducing conversion of chol to bile acids
Factors that inc and dec risk of endometriosis
Inc risk ~ nulliparity, early menarche, prolonged menses; dec risk ~ multiparity, extended lactation, late menarche (less frequent menstrual cycles and dec opportunity for endometrial cells to be disseminated outside of uterus)
Classic test for Meckel diverticulum
Inc uptake of 99Tc-pertechnetate in the RLQ. Ectopic gastric mucoas in the Meckel diverticulum secretes acid, causing local ulceration and bleeding; 99Tc-P binds parietal cells in gastric mucosa
Incarceration vs strangulation
Incarceration - cannot be reduced (femoral hernias prone to this --> N/V/abd pain, bowel obstruction), strangulation - ischemia and necrosis of contents of hernia sac --> fever
MOA of oseltamivir and neuraminidase inhibitors
Inhibit virion release
Effect of estrogen on T3/T4
Increase in estrogen (pregnancy, OCP, HRT) raises circ TBG levels --> inc total T3/T4, normal free T3/T4
Conn's syndrome
Increased aldosterone secretion, hyperplasia of glomerular layer
Why do myeloproliferative d/o predispose to gout?
Increased urate production by myeloproliferation --> hyperuricemia (overproductive causes are 1° gout, myelo/lymphoprolif d/o, TLS, HGPRT)
Nitrite poisoning
Induce conversion of heme iron from Fe2+ to Fe3+, forming methemoglobin. Methemoglobin can't bind O2, residual ferrous iron left shifts, but PaO2 is unchanged (dissolved in blood)
Insulin dep and indep organs (GLUT4 is responsive to insulin)
Insulin dep (adipocytes and skel muscle), insulin indep (BRICK LIPS - brain, RBCs, intestine, cornea, kidney, liver, islets, placenta, spermatocytes)
Most important risk factor for cervical dysplasia
Infection w/ HPV 16/18. Cervical cancer is rare in young immunocompetent women (50% of pts w/ untreated high-grade dysplasia have spont regression). Pts w/ HIV are prone to cancer from T cell def
Conditions that cause hyperglycemia in T1DM
Infection, pain, and sleep deprivation cause release of catecholamines, which raise glu by dec panc insulin secretion and inc glycogenolysis and GNG
Anterior uveitis
Infectious processes (herpes viruses, syphilis, Lyme), and inflam conditions (HLA B27, sarcoid)
Effect of elev FFA on insulin resistance
Insulin resistance hinders anti-lipolytic effects of insulin --> inc serum FFA impairs insulin-dep glu uptake --> inc hepatic GNG
How do you detect pulsus paradoxus?
Inflate BP cuff above systolic BP and deflate it. Diff b/n SBP where Korotkoff sounds heard only during exp and when they are heard at all phases of resp
Optimal site for femoral nerve block
Inguinal crease at the lateral border of the femoral artery --> anesthetizes skin and muscles of ant thigh, femur and knee
Borders of the femoral triangle
Inguinal lig sup, sartorius m lat, adductor longus m medially
S/e of halothane on liver (used abroad, replaced in US by enflurane, isoflurane, desflurane, sevoflurane)
Inhaled anesthetic hepatotoxicity, hepatocellular pattern of liver injury --> rapid atrophy, shrunken on autopsy, widespread centrilobular necrosis and inflam of portal tracts. Hypersensitivity rxn to drug causing immune med attack on hepatocytes. Sx: fever, anorexia, nausea, myalgias, rash, tender hepatomegaly, jaundice, elev AST/ALT, inc PT, eosinophilia
Otosclerosis
Inherited condition of middle age. Conductive hearing loss due to bony overgrowth of stapes.
AT III deficiency
Inherited or acquired (cirrhosis, nephrotic syndrome). Sx: VTE (DVT, PE), resistance to heparin
Oxoanions (perchlorate, pertechnetate)
Inhibit Na/I symporter and reduce iodine uptake by thyroid
Use of somatostatin
Inhibit bioactive amine release, used to treat diarrhea in pts w/ carcinoid syndrome and VIPoma, also tx of acute esophageal variceal hemorrhage
Cromolyn and nedocromil
Inhibit mast cell degranulation, but do not affect bronchial constriction --> good for prevention, not treatment of acute exacerbations
Chronic idiopathic urticaria
Inhibition of COX1 by aspirin and NSAIDs can trigger urticaria by shunting arachidonic acid metabolites towards formation of LTs
Basophilic stippling
Inhibition of erythrocyte 5' nucleotidase by lead --> ribosome aggregation due to inability to degrade RNA --> blue dots in cyto of RBCs
Effect of cyanide poisoning on PaO2 and SaO2
Inhibits cellular ox phos, inhibits Fe3+ in cyto c oxidase. Lowers peripheral tissue oxygen consumption. PaO2, SaO2, CaO2 are same, venous O2 content rises
Warfarin-induced skin necrosis
Inhibits epoxide reductase (regenerating Vit K) --> FVIII and Prot C depleted first due to short half life, transient hypercoag state, microvasc occlusion, hemorrhagic skin necrosis. Tx: FFP. To prevent, always start w/ "heparin bridge"
Metformin MOA
Inhibits mitochondrial glycerophosphate dehydrogenase, thus reducing hepatic GNG. Alpha-glucosidase inhibitors dec activity of memb-bound disaccharidases on intestinal brush border
Flucytosine
Inhibits syn of DNA (replication) and RNA (prot syn) in fungal cells, synergistic w/ amphotericin B, imp in tx of cryptococcal meningitis
Down syndrome (Trisomy 21)
Intellectual disability, flat facies, prominent epicanthal folds, duodenal atresia, Hirschsprung dz, cong heart dz, inc risk of AD, ALL and AML, single palmar crease, SMALL EARS, upsplanting palpebral fissures, protruding tongue, excessive skin at nape of neck
Naturally competent bacteria
Innate capacity to undergo transformation --> Haemophilus, Streptococcus, Bacillus, Neisseria
Pathogenesis of malaria
Inoculated by Anopheles mosquito, travel to liver and infect hepatocytes and replicate --> lysis of infected hepatocytes releases merozoites into bloodstream --> infect RBCs, RBC lysis causes relapsing fevers. Vivax and ovale have latent hepatic infection in form of hypozoites, responsible for relapses.
Motion sickness
Input from vestibular, visual, and somatosensory systems is integrated in vestibular nuclei via muscarinic M1 and histaminic H1 --> scopolamine, meclizine, dimenhydrinate
Laryngomalacia
Inspiratory stridor during infancy due to collapse of supraglottic structures during inspiration, stridor is worse in supine position, improves w/ upright positioning
Regulation of fructose-2,6-bisphosphate
Insulin activates PFK-2, leading to inc F-2,6-BP levels and augmented glycolysis. High F-2,6-BP inhibit GNG, decreasing alanine conversion to glucose
NPH
Intermediate acting insulin composed of crystalline suspension of insulin w/ protamine and zinc, delays absorption of insulin from subQ infection site
Symptoms of polyarteritis nodosa
Intermittent episodes of abdominal pain, peripheral neuropathy, renal insuff, severe HTN
Nerve in piriform recess, and function
Internal branch of superior laryngeal nerve, impaired cough reflex on transection
How does silicosis predispose to TB
Internalized silica particles disrupt macrophage phagolysosomes
Rapid intraluminal expansion
Intestinal-type adenocarcinomas of the stomach, resemble colon cancers
Locations of uterine fibroids
Intracavitary, intramural, submucosal, subserosal. Fibroids are characterized by irregular uterine enlargement --> pelvic pressure. In post uterus, cause constipation
Prussian blue
Intracellular iron. Golden cytoplasmic granules in Mo that turn blue --> hemosiderin laden Mos. Colorless K ferrocyanide (colorless) + FeX3 --> Fe3 ferrocyanide (blue-black) + KX
Which bacteria are destroyed by cell-mediated immunity?
Intracellular pathogens (Chlamydia, Legionella, Listeria etc.). Presented on MHC I --> activate CD8 T cells --> release IFN-g to activate Mo
Brain AVM
Intracranial hemorrhage in children
Most common cause of blood-tinged nipple d/c
Intraductal papilloma (prolif of papillary cells in fibrovasc core)
Pathology of atopic eczematous dermatitis
Intraepidermal vesicles, superficial epidermal hyperkeratosis producing scale, epideral hyperplasia (acanthosis), chronic inflam infiltrate of dermis
Muscle spindles
Intrafusal muscle fibers are in parallel w/ extrafusal fibers, innerv by group Ia and II sensory axons, sensitive to changes in muscle LENGTH. Mediate myotatic/stretch reflex (DTRs)
von Hochstetter's triangle
Intragluteal injections should target the anterolateral gluteal area (between second and third digits of outstretched hand)
Treatment of alopecia areata
Intralesional glucocorticoids
Autoimmune gastritis
Involves body and fundus of stomach, spares antrum. CD4 T cell mediated parietal cell destruction --> achlorhydria and pernicious anemia
PAN spares which vessels?
Involves renal and visceral vessels (kidney, liver, heart, GI tract), sparing pulmonary aa. One third of pts have cutaneous manifestations (livedo reticularis, palpable purpura)
Function of TPO
Iodine organification and coupling of iodotyrosines. Production of colloid is regulated only by TSH
Sx of L cerebellar hemisphere lesion
Ipsilat dysdiadochokinesia, limb dysmetria, intention tremor
Saccular aneurysm compressing right posterior comm artery
Ipsilateral CN III palsy. Saccular aneurysms arise from branch points on CoW, most affect ant circ, RFs are chronic smoking and poorly controlled HTN
Which compounds are malabsorbed after gastrojejunostomy?
Iron (duod and prox jejunum), folate (small bowel), B12 (term ileum), ADEK, calcium. Iron Fist, Bro.
Galactosemia (galactose-1-phosphate-uridyltransferase def)
Jaundice, vomiting, poor feeding, lethargy, hypoglycemia, hepatomegaly, infantile cataracts, E coli sepsis in neonates. Galactose-1-P accum in neonates
Most common location for saccular aneurysms
Jcn of ant comm a and ACA - result in bitemp hemianopsia
Location of SA node
Junction of R atrium and SVC. AV node is located in the RA near the insertion of the septal cusp of the tricuspid valve and the orifice of the coronary sinus. Area around opening of pulm vv in LA involved in a-fib.
Progression of melanocytic nevi
Junctional nevi - at DEJ, FLAT, darker black. Compound nevi - at DEJ and extend into dermis, RAISED, brown to tan. Intradermal - older lesions, epidermal nests are lost. Remaining dermal cells lose tyrosinase activity and produce no pigment. Intradermal nevi are skin to tan colored, dome-shaped.
What determines the QT interval (APD)? Congenital causes of LQTS?
K+ currents thru channel proteins. Jervell and Lange-Nielsen (w/ neurosensory deafness) and Romano-Ward (no deafness), predispose to TdP at young age
How do ketone bodies generate energy?
Ketone bodies are generated in the liver from fatty acids and yield energy when converted into acetyl-CoA in the mito. RBCs can't use ketones, neither can liver (lacks essential enzyme)
How does urinary H2PO4 change in DKA?
Kidneys correct metabolic acidosis by 1) inc HCO3 reabsorption (low urinary HCO3-), 2) inc H+ secretion, and 3) inc acid buffer excretion (pH changes rapidly w/ small changes in [H+], so there is a limit on amt of free H+ that can be excreted into urine. Kidney uses buffers to trap H+ and allow excretion of large amts of acid w/o markedly lowering urinary pH. Kidneys excrete more H2PO4- (to make H3PO4) and inc NH3 prod (NH4+ excretion) in chronic acidosis
Mechanism of SBO in midgut malrotation
Ladd's bands (connect retroperitoneum to R colon/cecum) pass over 2nd part of duod --> obstruction, painful bilious emesis in newborn, may cause volvulus ("corkscrew" appearance).
Selective media vs differential media
Kill potential contaminants (VPN selective agar), differential ~ identify organisms based on metabolic and biochem properties (MacConkey, EMB), enrichment ~ FV/X for H flu, reducing ~ remove oxygen and culture anaerobic organisms
What is the most common cause of necrotizing pneumonia in elderly/immunocompromised?
Klebsiella
Donovanosis (granuloma inguinale)
Klebsiella granulomatis - painless, beefy red serpigious ulceration w/o lymphadenopathy. Intracytoplasmic Donovan bodies are diagnostic. If left untreated, scarring and strictures --> severe lymphatic obstruction and lymphedema
Raisinoid apperance
Koilocyte
Perinuclear vacuolization
Koilocytic change due to HPV infection and viral proteins
Which sequence initiates eukaryotic translation?
Kozak sequence, analogous to the Shine-Delgarno sequence of E coli. Defined by (gcc)gccRccAUGG, where R=A or G --> mutations here impair initiation of translation
Which ribs overlie which organs
L 12th rib - overlies parietal pleura medially and kidney laterally, R 8-11th ribs ~ liver, L 9-11th ribs ~ spleen, ribs 1-6 fracture damages visceral pleura
Which arteries bleed due to gastric ulcer hemorrhage?
L and R gastric aa (run along the lesser curvature of the stomach) or gastroduodenal a (post wall of duodenum)
Preferred vessel used for CABG when LAD is occluded
L int mammary (thoracic) a, or great saphenous v if multiple coronary aa require revasc
Frontal lobe syndromes
L sided lesion ~ apathy and depression. R sided lesion ~ disinhibited behavior
Which side is varicocele common in men?
L sided varicoceles can be normal due to aorta and SMA compression of L renal vein (nutcracker effect). R sided hydronephrosis in pregnancy is normal (L ovarian v drains into renal vein, R ovarian v drains into IVC)
A-fib meds that cause constipation, new onset 2° heart block, syncop
L-type Calcium channel blocker (diltiazem and verapamil)
Leukocyte adhesion deficiency (three types)
LAD1 - absence of CD18, can't synthesize beta-2 integrins --> no adhesion, recurrent skin infections w/o pus, delayed detachment of umbilical cord. LAD2 - less severe, fewer infections. LAD3 - severe, due to affected beta-3 integrins on platelets
WHERE DO NITRATES ACT
LARGE VEINS, cause systemic venodil and inc venous capacitance. Pharmacologic nitrates metabolized to NO by mito aldehyde dehydrogenase in vasc SMCs
Why does exercise inhibit glycolysis in a pt w/ nonfunctional LDH
LDH regenerates NAD+ by converting pyruvate to lactate; exercise requires anaerobic glycolysis b/c O2 is depleted, and high NADH/NAD+ ratio halts glycolysis
LEMS vs MG Abs
LEMS - Abs against PREsynpatic VGCC, MG - Abs against POSTsynaptic nAChRs
Where do optic tract fibers project?
LGN, sup colliculus, pretectal area (light reflex), SCN (circardian rhythms)
What do integrins bind to?
Laminin, fibronectin (prod by fibroblasts), collagen
E coli virulence factors
LPS ~ bacteremia/septic shock, capsular polysaccharide ~ neonatal meningitis, shiga-like toxin ~ bloody gastroenteritis, heat stable enterotoxin ~ watery gastroenteritis, fimbriae ~ UTIs
Important chemotactic agents
LTB4, 5-HETE (LT precursor), C5a, IL-8
Lac operon structural genes
Lac Z - beta-galactosidase (hydrolysis of lactose to glucose and galactose), Lac Y - permease (allows lactose to enter), Lac A - beta-galactoside transacetylase (transfers acetyl groups to beta-galactosides)
Specific findings for opioid w/d vs other sedatives
Lacrimation, yawning, dilated pupils
Which sources are used in GNG? Which glycolysis enzymes are unidir
Lactate, glycerol, glucogenic AAs. Unidir enzymes are hexokinase, PFK, pyruvate kinase
Hemiballismus is due to what?
Lacunar stroke (longstanding HTN and DM) --> damage to STN
Unilat MLF lesion in old pt w/o MS
Lacunar stroke in pontine artery distribution
CSF flow
Lat ventricles --> foramen of Monroe --> 3rd vent --> cerebral aqueduct --> 4th vent --> foramen of Magendie/Luschka --> subarachnoid space
Dressler's syndrome
Late-onset (1 wk - mos) post-MI pericarditis. Sx: fever, pleuritis, leukocytosis, pericardial friction rub, new pericardial/pleural effusions. Autoimmune polyserositis provoked by Ags created by infarction of cardiac muscle --> diffusely inflamed. May involve serosal surface of lung. Tx: aspirin, NSAIDs, glucocorticoids
Location of trigeminal nerve
Lateral aspect of mid-pons at level of MCP
Traumatic vertebral dissection in a young pt
Lateral medullary syndrome (Wallenburg)
Stimulus control therapy
Leave bed when unable to sleep so you don't associate negative feelings w/ bed. (NB: Elim of coffee and etoh and avoiding naps are examples of sleep hygiene)
Diseases of heteroplasmy
Leber hereditary optic neuropathy (bilat vision loss), myoclonic epilepsy with ragged red fibers, mito encephalomyopathy with lactic acidosis and stroke-like episodes (MELAS)
Measure of fetal lung maturity
Lecithin (phosphatidylcholine) to sphingomyelin ratio (L/S). Surfactant ~ DPPC, memb phospholipid ~ sphinomyelin. Until 33 wks gestation, L/S ratio is 1:1. At 35 wks gestation, L/S ratio is 2:1
Most useful measure for severity of MS
Length of A2-OS interval
Marfan syndrome
Lens dislocation (up and out), aortic root dilation, arachnodactyly, scoliosis, MVP
Multinuc giant melanocytes
Lentigo maligna melanoma (elderly people, "melanoma in situ")
Loss of sensation at med aspect of leg
Lesion of saphenous nerve, largest pure sensory branch of femoral n
Most common site of gastric ulcers
Lesser curvature of stomach, at transitional zone b/n gastric corpus and antrum --> optimal microenv (pH, host immune factors)
Which structure must adjustable gastric banding pass in upper stomach?
Lesser omentum (spans from liver to lesser curvature of stomach. Consists of 2 ligaments, hepatogastric and hepatoduodenal).
Leucovorin and MTX
Leucovorin rescues bone marrow and GI and other mucosal cells from MTX tox. When in combination w/ 5-FU, leucovorin potentiates cytotoxic action of 5-FU (binding thymidylate synthase), used in CRC chemo regimens
Palpable purpura
Leukocytoclastic vasculitis. Petechiae and purpura are collections of extravasated blood from small-vessel bleeding due to platelet dysfcn or cap fragility
Pharmacologic antagonists in tx of allergic asthma
Leukotrienes (LTC4, LTD4, LTE4) and acetylcholine antag
Lewy body dementia
Lewy bodies (IC eosinophilic inclusions of alpha-synuclein). P/w attention deficits, visual hallucinations, spont parkinsonism (bradykinesia, rigidity, resting tremor)
Prostatic plexus (injury causes ED)
Lies w/in fascia of prostate and originates from inferior hypogastric plexus. Lesser and greater cavernous nerves arise from prostatic plexus and pass beneath pubic arch to innervate corpora cavernosa of penis and urethra
Cerebellar hemisphere due to involvement of lat descending motor sys
Limb dysmetria (overshoot/undershoot)
Presentation of achondroplasia
Limb shortening w/ normal torso length, frontal bossing, midface hypoplasia, aut dom. Mut in FGFR3 --> inhibition of chondrocyte prolif --> less endochondral ossification. Flat bones go straight from mesenchyme to osteoblasts w/o cartilage, so they are not affected
Insula
Limbic system (emotion) and coordination of autonomic fcns, esp cardiac
Ways to reduce suicide risk (modifiable factors)
Limiting access to firearms (3x rate of completion)
ToGA is due to what?
Linear rather than spiral develoment of the aorticopulmonary septum in utero
Dystrophin
Links cytoskeletal component (actin) to sarcolemma (alpha and beta dystrophiglycans). Found in familial DCM and Duchenne/Becker
All Enterobacteriaceae contain what endotoxin?
Lipid A
Yellow-brown granules found in elderly pt's heart
Lipofuscin - "wear and tear", product of free radical injury and lipid peroxidation
Lipohyalinosis vs microatheromas
Lipohyalinosis - leakage of plasma prots thru damage endothelium, causes hyaline thickening of vascular wall. Microatheromas - atherosclerotic accum of lipid-laden Mo w/in intima of penetrating a
Mood stabilizers in bipolar d/o
Lithium (manic and depressive features), valproate (manic features), carbamazepine (manic features), lamotrigine (depressive features)
Labs to check while on antipsychotics
Lithium - hypothyroidism, impaired renal fcn. Clozapine - agranulocytosis. Ziprasidone - QT prolongation. Risperidone - prolactin elev.
Mood stabilizers in bipolar d/o
Lithium - manic and depressive features, valproate - manic, carbamazapine - manic, lamotrigine - depressive
Only two drugs ever proven to decrease suicide risk
Lithium and clozapine
Categories of liver tests
Liver function ~ PT, bilirubin, albumin, cholesterol, structural integrity ~ AST/ALT, biliary tract ~ ALP, GGT
Determinant of prognosis in cirrhosis pt
Liver functional reserve (serum albumin level, bili, PT), NOT degree of liver injury (AST/ALT).
Hers disease
Liver glycogen phosphorylase deficiency. Presens in early childhood w/ mild hypoglycemia, ketosis, and hepatomegaly. No effect on skel muscles, has excess normally structured glycogen on liver biopsy
Where is FVIII produced?
Liver sinusoidal cells
Cerebral amyloid angiopathy
Lobar hemorrhages in elderly (occipital, parietal). Beta-amyloid (AD) deposition in walls of small to medium cerebral aa, predispose to rupture
Lat geniculate nucleus
Located in the thalamus, relays visual info to ipsilat 1° visual cortex. Damage results in contralat homonymous hemianopsia
S/e of selective arteriolar vasodilators (hydralazine, minoxidil)
Lower BP by reducing SVR --> stim of baroreceptors causes RAAS activation --> sodium and fluid retention w/ peripheral edema. Used in Raynaud's b/c they enhance blood flow to peripheral tissues. Never given as monotherapy for HTN, used for severely elev BP acutely, or synergistic w/ sympatholytics and diuretics to lower resistant HTN
Tx of acute alcohol w/d
Long-acting benzos (diazepam, chlordiazepoxide). In pts w/ liver dz, prefer benzos that don't undergo ox metabolism in liver (LOT - lorazepam, oxazepam, temezepam)
On-off phenomenon
Long-term tx of Parkinson's w/ levodopa assoc w/ periodic fluctuations in motor fcn. As PD progresses, therapeutic window narrows due to nigrostriatal degeneration
Pt w/ Crohn dz has bruising, pain in back and jts
Loss of bile acids --> fat malabsorption --> Vit ADEK deficiency
Founder effect
Loss of genetic variability w/in a group that historically conceived w/in their own community
Consequences of nephrotic syndrome
Loss of immunoglobulins and LMW complement factors --> vulnerable to infections, esp pneumococcal. Lipiduria (Maltese cross in urine)
Symptoms of lead poisoning in children
Loss of milestones, constipation, abdominal pain, irritability, interstitial nephritis, anemia, pallor
Mitral stenosis murmur
Loud S1, early diastolic high-frequency opening snap after S2, low-pitched diastolic rumble. Shorter A2-OS interval --> more severe MS
Tx of CAH
Low (physiologic) doses of exogenous corticosteroids to suppress ACTH secretion
Factors affecting Vd (amount of drug given/plasma []). E.g, drug w/ high mol wt, high plasma prot binding, high charge, and hydrophilicity is trapped in plasma compartment and the Vd is low (3-5 L). Vd is the amount of fluid the drug would need to be distributed in to result in the observed plasma volume.
Low - stays IV - large/charged mols, bound to plasma proteins. Medium - ECF - small hydrophilic mols. High - all tissues incl fat - small lipophilic mols, drugs that bind avidly to tissues
Hypothyroidism thyroid labs
Low T4, elev TSH, normal T3 (because T3 is produced in peripheral tissues and has a short half-life, correlates poorly w/ clinical status)
Why are only upper lungs damaged in smoking emphysema?
Low V/Q ratio at apex of lungs --> lower presence of serum AAT, and toxic smoke particles can affect centriacini
AMS, enlarged ant fontanelle, downward driven eyes in neonate
Low Vitamin K stores, intracranial hemorrhage.
Sciatica
Low back pain radiating down one side of the hip to the leg. Can be compressed during pregnancy due to relaxin (stim by beta-hCG)
Why are pulm infarcts red and not white?
Low density of lung tissue (blood seepage into tissue during infarction), and dual blood supply
Lac operon conditions
Low glu, high lactose --> lot of transcription. High glucose, low lactose --> minimal transcription. High glucose, high lactose --> little transcription.
HMO
Low monthly premiums, low copayments and deductibles, low total cost to patient. Confining patients to limited panel of providers, require referral from PCP, deny payment for services that don't meet evidence-based guidelines
S/e of first gen antipsychotics (Very Potent = EPS)
Low potency (chlorpromazine, thioridazine) ~ sedation, anticholinergic s/e, orthostatic hypotension. High potency (haloperidol, fluphenazine) ~ EPS. Second gen ~ hyperglycemia
Triad of Meniere disease
Low-frequency tinnitus, vertigo, sensorineural hearing loss. Caused by inc vol and pres of endolymph due to defective resorption of endolymph
Where does A1AT (panacinar) emphysema occur first?
Lower lobe predominant
Sudden upward jerking of the arm injures what? Klumpke palsy
Lower trunk of brachial plexus --> median and ulnar n damage --> innervate all intrinsic muscles of hand (lumbricals, interossei, thenar, hypothenar)
Radioulnar articular disc with carpal bones
Lunate and triquetrum
Common pathology of PBC and GVHD
Lymphocytic infiltration and destruction of small intrahepatic bile ducts
S pyogenes virulence factors and toxins
M prot - evade phagocytosis, activate alternate complement pathway; hemolysins O/S - cause hemolysis; pyrogenic exotoxins (superAgs result in septic shock)
Direct vs indirect hernia
MDs don't LIe (medial to inf epigastrics = direct, lateral to inf epigastrics = indirect). Indirect more common. Direct thru Hesselbach's triangle, less prone to incarceration, less likely to descend into scrotum b/c no direct path. Indirect = go thru patent processus vaginalis (failed to obliterate), may enter scrotum)
Targets of MG vs LEMS
MG - anti-ACh-R, LEMS - antibodies against presynaptic Ca chan --> dec ACh release. LEMS improves w/ use, assoc w/ SCLC. MG worsens with use, improves w/ tensilon test
Structure of MHC I and II
MHC I - heavy chain only and beta2-microglobulin, MHC II - alpha and beta polypeptide chains
Why is M tb displayed on CD4 and not CD8 even though it lives in Mo?
MHC I presents Ags from organisms that replicate in the cytosol (viruses, Listeria etc.). M tb replicates w/in the phagolysosome, not the cytosol --> MHC II presentation
Derivatives of neural crest
MOtELL PASS: Melanocytes, myenteric (Auerbach) plexus, odontoblasts, endocardial cushions, laryngeal cartilage, parafollicular C cells, PNS (DRG, cranial nerves, autonomic ganglia), adrenal medulla and all ganglia, spiral membrane (aorticopulmonary septum), Schwann cells, pia and arachnoid, bones of skull
S/e of RA drugs
MTX - oral ulcers, alopecia, hepatotox. Hydroxychloroquine - irrev retinopathy, minocycline - photosensitivity dermatitis,
Leucovorin is used to rescue pts after taking which med?
MTX. Folinic acid/leucovorin is a reduced form of folic acid
Macula densa vs JG location
Macula densa - distal tubule, monitor salt content and tubular flow rate; JG cells - modified SM cells in aff art (RAS causes JG hyperplasia)
Function of APC
Maintain low levels of beta-catenin (oncogenic protein) and intracellular adhesion
Glutamine shuttle
Major AA in blood b/c it transports excess ammonia from peripheral tissues to kidney --> hydrolyzed in nephron to glutamate and free ammonium (excreted in urine)
Pityriasis versicolor
Malasezzia, confined to stratum corneum, common in hot and humid climates, visible after extensive sun exposure due to tanning of adjacent skin, "spaghetti and meatballs"
Fibrinoid necrosis and hyperplastic arteriolosclerosis
Malignant hypertension. Fibrinoid necrosis ~ localized destruction of vasc wall w/ circumferential ring of pink, amorphous mat'l surrounding lumen
Most common cause of sudden cardiac death first 48 h post MI
Malignant v-fib, related to electrical instability due to lack of perfusion in ischemic myocardium
Steps of inflam leukocyte accum
Margination: inc vasc leakage in microvasc; rolling: Sialyl-Lewis, L-selectin/E-selectin; activation: chemokines; tight adhesion: CD18-beta2 integrins to ICAM-1; transmigration: PECAM-1 at peripheral intercellular jcns of endoth cells
Congenital deficiency of FXII (Hageman)
Marked PTT prolongation w/o bleeding diasthesis, pts have tendency for thromboembolic complications
Acoustic neurona/Schwannoma
Mass lesion at cerebellopontine angle. Causes sensorineural hearing loss, vertigo, tinnitus, progressive.
MODY
Maturity onset diabetes of the young: AD, IMPAIRED GLUCOSE SENSING and insulin secretion. Non-insulin dependent diabetes at age <25
Ovulation predictor kit
Measures urinary LH and becomes +ve 24 h before ovulation
Course of the ulnar n
Medial cord of brach plexus (C8-T1), posteromed in upper arm, post to medial epicondyle, innerv FCU and FDP, at wrist passes b/n hook of hamate and pisiform (Guyon's canal) --> innerv medial 1.5 digits and hypothenar eminence
Medial and lateral tracks of sup lymphatic sys in LE
Medial track runs up long saphenous v, bypasses popliteal nodes and enters superficial inguinal nodes. Lateral track comm w/ popliteal and inguinal nodes
Kawasaki dz
Medium-vessel vasculitis, persistent fever for >= 5 d, bilat conjunctivitis, cervical lymphadenopathy, strawberry tongue, edema of hands/feet --> coronary a aneurysm
Meds that cause osteoporotic frac
Medroxyprogesterone - dec estrogen, GnRH agonists - dec T and E2, PPIs - dec Ca absorption, glucocorticoids - dec bone formation, anticonvulsants/aromatase inhibitors
Where do lat corticospinal tract fibers decussate?
Medulla. Ones that do not form the ant corticospinal tract. UMN only - stroke, brain tumor. LMN only - poliomyelitis, infantile SMA. Both - ALS
MEN 2B (AD germline mut in RET)
Medullary thyroid cancer, pheo, mucosal neuromas/Marfanoid habitus (flesh colored nodules on lips and tongue), intestinal ganglioneuromas (constipation)
Arteriovenous malformation
Most common cause of intracranial hemorrhage in children
Progressive neuro sx and well-circumscribed parasagittal tumor
Meningioma. Arise at dural reflections (falx cerebri, tentorium cerebelli)
Drugs that mimic FSH and LH
Menotropin (human menopausal gonadotrophin) mimics FSH, exogenous hCG is structurally similar to LH
Why do women develop sx of hemochromatosis later than men?
Menstrual losses in premenopausal women keep total Fe body stores <20 g, which is when the disease manifests
Abdominal pain and jaundice, cholestasis and hepatitis
Mercaptopurine (S-phase specific)
Types of exocrine glands
Merocrine - cells secrete via exocytosis (salivary glands, eccrine sweat glands, apocrine sweat glands), apocrine - cells secrete via memb-bound vesicles (mammary glands), holocrine - lipid rich, cell lysis release entire contents of cytoplasm and cell membrane (sebaceous glands, Meibomian glands)
Dopaminergic pathways
Mesocortical ~ negative sx, mesolimbic ~ positive sx, nigrostriatal ~ EPS, tuberoinfundibular ~ inc prolactin
Broad ligament
Mesosalpinx (descends from fallopian tube), mesoovarium (inf to mesosalpinx, covers ovarian hilum), mesometrium (inf to mesoovarium)
Dec thiopurine methyltransferase
Metabolism of purine compounds such as 6-mercaptopurine
Nephrilysin
Metalloprotease that inhibits several peptide hormones incl bradykinin, glucagon, enephalins, ANP/BNP. Nephrilysin inhibitor (sacubitril) useful in HF pts
Hematogenous osteomyelitis in kids affects what part of bone?
Metaphysis of long bone, b/c of slow-flowing sinusoidal vasculature
BRAF, V600E
Metastatic melanoma. Tx: vemurafenib
Leukocytoclastic vasculitis (type of cutaneous small cell vasculitis, defined by neutrophilic infiltrate. In adults, cutaneous small vessel vasculitis is mononuclear predominance. Only affects skin).
Microscopic polyangiitis, microscopic polyarteritis, hypersensitivity vasculitis. Segmental fibrinoid necrosis of small vessels; in first 24 h, perivasc inflam cells are mostly PMNs and fragmented PMN nuc. Due to antibiotic use (pencillins, cephalosporins, sulfonamides, phenytoin, allopurinol) or viral hepatitis; patients develop nonblanching petechiae or palpable purpura w/o sig bleeding
Micturition reflex
Micturition reflex: 1) Sacral micturition center (S2-4, parasymp stim bladder contraction), 2) pontine micturition center (relaxation of ext urethral sphincter), 3) cerebral cortex (inhibits sacral micturition center)
Fixed and dilated pupils in anoxic brain injury due to what?
Midbrain damage - fixed b/c the pretectal nuc is nonfunctional and the pupillary light reflex is impaired. Bilat pontine injury assoc w/ pinpoint pupils due to damage to symp fibers
Primary blood supply to ACL
Middle geniculate artery - injuries characterized by rapid-onset hemarthrosis and knee swelling
Fracture at pterion (FPTS bone intersection)
Middle meningeal a laceration (branch of maxillary) --> epidural hematoma --> uncal herniation and CN III palsy, elev ICP, death
Whipple disease
Migratory polyarthritis, followed by abd pain, malabsorptive diarrhea. Neuro sx (cognitive dysfcn, myoclonus), cardiac dz (endocarditis)
Signs of irreversible tissue injury
Mitochondrial vacuolization, nuclear shrinkage (pyknosis), fragmentation, and dissolution
Diastolic murmur w/ presystolic accentuation by atrial contraction
Mitral or tricuspid stenosis - a-fib causes it to disappear completely
Identification
Modelling one's behavior after someone more powerful or prestigious
Expression cloning
Modification of eukaryotic cDNA to promote optimal protein expression (addition of prokaryotic promoter sequences (Pribnow box) and ribosomal binding site (Shine-Dalgarno seq))
Pathophys of Guillain Barre
Molecular mimicry: infectious agent contains ganglioside-like substance in LPS layer --> Abs cross-react w/ gangliosides in myelin and Schwann cells --> ascending symmetric muscle weakness, areflexia, CN VII palsy
Atypical depression is characterized by what sx?
Mood reactivity, leaden paralysis, rejection sensitivity, inc sleep and appetite. Tx of atypical depression is MAOI
Glargine and detemir
More AA substitutions (precipitates in subQ tissue) and covalently bonded FA to allow for slow, sustained release
Acute phase reactants (inc ESR, allow RBC to overcome zeta pot)
More FFiSH in the C (sea) - ferritin, fibrinogen, serum amyloid A, hepcidin, CRP
Pathophys of high pressure communicating hydrocephalus
More acute impairment in CSF absorption (central venous sinus thrombosis, meningitis, acute SAH) - AMS, sz, HA, focal neuro deficits
Markers for Mos, NK cells, and hematopoietic stem cells
Mos - CD14 (binds to LPS)/CCR5, NK - CD16/56, HSC - CD34
Where does deoxy blood mix w/ pulm v blood and cause Aa diff?
Most blood from the bronchial aa returns deoxygenated into the L heart via pulm vv, and small cardiac (thesbian) vv drain into LA/LV
Cavernous hemangioma
Most common benign liver tumor, adults age 30-50, congenital malformations that enlarge by ectasia. Well-circumscribed, spongy consistency. Histo: cavernous, blood-filled spaces, of variable size lined by single epith layer. Excellent prog
Diabetic nephropathy
Most common cause of ESRD in US. Prog loss of heparan sulfate (-ve charge) from GBM --> leakage of albumin and plasma prot (30-300 mg albumin loss/d). Albumin-specific urine dipstick to monitor progression
MVP
Most common in connective tissue d/o (Marfan, Ehlers-Danlos)
SCC of ear
Most common malig tumor of ear canal, presents as ulcerated plaque or nodule, local or regional pain
Prostate cancer
Most common non-skin cancer in men, African-American men at highest risk, irreg prostate on DRE is diagnostic. Sx: bone pain, cancer cachexia, urinary sx
Cardiac myxomas
Most common primary cardiac neoplasm, 80% originate in L atrium. Obstruct flow across mitral valve --> syncope and sx of HF. Scattered cells w/in a mucopolysaccharide stroma. Prod large amt of VEGF (friable and hemorrhaging) and IL-6 (fever, wt loss, constitutional sx)
Abetalipoproteinemia
Most commonly caused by AR, LoF mut in MTP gene (microsomal triglyceride transfer prot allows for apoB folding). Manifests in 1st year of life w/ malabsorption (abd distension, foul-smelling stool), low plasma triglyceride and chol, absent chylomicrons, VLDL, apoB. ADEK def, acanthocytes, neuro abnormalities (prog ataxia, retinitis pigmentosa)
Clavicle fracture
Most commonly fractured bone, often in young children, SCM tethers the superomedial aspect and dispaces med fragment superiorly. Arm and pec major cause inf displacement of lat fragment.
Pathogenesis of Pompe dz (on muscle biopsy, glycogen accum in lysosomes)
Most glycogen is degraded in cytoplasm, but some is inadvertently engulfed by lysosomes --> cannot be processed, massive lysosomes prevent contraction of cardiac and skel muscle. Sx: cardiomegaly, hypotonia
Heparin-induced thrombocytopenia
Most important cause of thrombocytopenia in hospitalized pts, causes paradoxical thrombosis, more common w/ UFH than LMWH
Clearance of anesthetics
Most inhaled anesthetics are exhaled from lungs into air, but halothane is metabolized exclusively by the liver --> hepatotoxicity
Why are catalase neg organisms unable to replicate in CGD?
Most microorganisms gen H2O2 as byproduct of metabolism, and catalase neg cannot prevent accum of H2O2 w/in phagosome --> phagocyte can gen microbicidal agent even if host superoxide prod is impaired
Brain regions supplied by basilar a
Most of brainstem and bilat cerebellar hemispheres
Functions of CN VII
Motor - facial muscles, parasymp to lacrimal/submandibular/sublingual, taste ant 2/3rds of tongue.
Functional anatomy of cerebellum
Motor execution (Vermis - medial descending systems, intermediate hemisphere - lat descending sys), lat hemisphere - motor and premotor cortices (motor planning), F-N lobe - vestibular nuc (balance and eye movements)
Sectional anatomy of spinal cord (C, T, L, S)
Moving rostrally, amt of white matter inc and sections become more ovoid. Only thoracic has lateral horns (made up of sympathetic preganglionic neurons). Lower cervical and lumbosacral have large ventral horns (innerv arms and legs, respectively).
Opioid receptors
Mu (physical dependence, euphoria, resp and cardiac depression, reduced GI motility, naloxone acts here), kappa (miosis), delta (antidepressant effects)
S/e of morphine causing RUQ abd pain
Mu opioid analgesics cause contraction of SM in sphincter of Oddi --> biliary colic
Histology of Krukenberg tumor
Mucin-secreting signet cells
Histopath findings of GERD
Mucosal erythema/edema in distal esophagus, erosions/ulcerations, basal zone hyperplasia, elonation of LP papillae, scattered eos and PMNs
P-glycoprotein
Multidrug resistant protein (MDR1). Overexpression of P-gp drives efflux of chemotherapeutics out of cell --> resistance
Histology of transitional cell tumors
Multifocal sessile or papillary tumors, malig epith cells are pleomorphic and have hyperchromatic nuc, inc N:C ratio
Means of transmission of sz and cystic brain lesion in Guatemalan pt
Neurocysticercosis - exposure to infected stool (containing eggs)
Central canal
Multiple concentric lamellae of bony matrix that contain lacunae filled w/ osteocytes and EC bone fluid
CXR of coal worker's pneumoconiosis
Multiple discrete nodules (1-4 mm), most prominent in upper lung zones. Histology of nodal and perilymphatic lung tissue shows accum of coal-dust laden Mos
Vascular dementia
Multiple lacunar infarcts - stepwise decline in cognitive fcn, focal neurologic deficits
Cast nephropathy
Multiple myeloma (large amts of monoclonal free chain deposition in kidney)
Childhood rash that causes orchitis/parotitis
Mumps
Classic viral findings
Mumps ~ parotitis/orchitis/aseptic meningitis, pertussis ~ paroxysmal cough, epiglottitis/upper aw obstruction ~ H flu b
Which tumors are chromogranin/synaptophysin/neuron-specific enolase +ve?
Neuroendocrine tumors (Carcinoids, SCLC, paragangliomas)
Baclofen
Muscle relaxant that affects GABA_B receptors at SC. Used to treat muscle spasticity
Hypervitaminosis D
Muscle weakness, confusion, constipation, impaired []ation of urine in distal tubule (polyuria, polydipsia), renal stone formation, bone pain
Muscules innervated by mandibular n (V3)
Muscles of mastication (medial and lateral pterygoid, masseter, temporalis), mylohyoid, tensor veli palatini, tensor tympani of middle ear
Charcot-Marie-Tooth
Mut of genes responsible for myelin syn. P/w distal muscle weakness, sensory loss, calf atrophy (STORK LEG DEFORMITY). Hammer toe
Limb girdle muscular dystrophy
Mutated sarcolemmal protein (caveolin). Dec # of functional T-tubules per muscle cell leads to uncoordinated contraction of myofibrils --> muscle weakness
What is responsible for new HIV-1 escape mutants after 1° infection?
Mutations in Env gene. Humoral response against HIV is due to neutralizing Abs directed against epitopes of viral envelope glycoprots. Escape mutants are no longer susceptible to host Ab neutralization
What is responsible for emergence of protease inhibitor resistant variants of HIV?
Mutations in Pol genes, also responsible for structural changes in HIV-1 RT that render it resistant to NRTI and NNRTI
Fanconi anemia
Mutations in genes for repair of interstrand DNA crosslinks. Sx: most common inherited cause of aplastic anemia. P/w short stature, hypoplastic thumbs, inc malig (AML)
Cold agglutinins and walking pneumonia
Mycoplasma pneumoniae
MERRF
Myoclonic epilepsy with ragged red fibers, mito myopathy
Primary carnitine deficiency
Myopathy (elev CK, weakness), cardiomyopathy (S3 gallop), hypoketotic hypoglycemia, dec muscle carnitine --> no beta-ox of FAs into acetyl-CoA, no ketogenesis
Most common anatomic abnormality producing MR
Myxomatous degeneration (MVP)
Regulator of the urea cycle
N-acetylglutamate (NAG) activates CPS I
Peptidoglycan precursor mols
N-acetylmuramic acid and N-acetylglucosamine
NF2 vs NF1 (both AD)
NF2 has fewer cutaneous manifestations, CNS involvement
Which factors are secreted by vasc endoth to inhibit plt aggregation?
NO and prostacyclin (PGI2). Normally, prostacyclin exists in dynamic balance w/ TXA2 in capillary endoth --> damaged endoth cells cannot synthesize prostacyclin, predispose to thrombi/hemostasis
Does HIV increase risk of disseminated candidemia?
NO. T lymphocytes only prevent superficial candida. Pts w/ HIV have superficial candidiasis, but PMNs are intact --> no candidemia
Ring enhancing lesion w/ pneumonia, Gram +ve seen on stain
NOCARDIA!! Ring enhancing is abscess
Which medications are CI in pt w/ gout and hx of PUD?
NSAIDs! Cause nausea, dyspepsia and bleeding by removing protective PG layer over gastric mucosa
Psoriasis complications
Nail pitting, psoriatic arthritis (asymmetric polyarthritis, arthritis mutilans)
Most common cause of unilat fetal hydronephrosis
Narrowing or kinking of prox ureter at UPJ (UPJ is last segment of ureteric bud to canalize, may persist w/ abnml Col and circular musc)
IL-12 receptor deficiency
Naïve T cells unable to differentiate into Th1 subpop --> no prod of IFN-g --> Mo cannot be activated, no Type IV hypersensitivity --> severe mycobacterial infections
IL-4 receptor deficiency
Naïve T cells unable to differentiate into Th2 subpop --> no B cell differentiation into plasma cells or secretion of Ig --> administer IL-4 to improve immune response to EC viruses or bacteria
Most frequent site of common peroneal n injury
Neck of fibula --> weakness on foot dorsiflexion (foot drop) and eversion, impaired sensation over lat shin and dorsal foot, and b/n 1st and 2nd toes
SubQ rheumatoid nodules
Necrotic center surrounded by palisading Mos and lymphocytes
Infant w/ abd distension, bloody stools, pneumatosis intestinalis (air in bowel wall, thin curvilinear areas of lucency)
Necrotizing enterocolitis. In preterm infants, gastrointestinal and immunologic immaturity --> bacteria enter bowel during enteric feeding, prolif excessively and invade bowel wall due to reduced immune fcn --> ischemic necrosis of term ileum/colon. Death by intestinal perforation, survivors at risk for strictures/bowel obstruction due to fibrosis
Ophthalmia neonatorum
Neonatal conjunctivitis due to Chlamydia, Neisseria, viruses. Acquired during birth
Abnormal retinal vascularization that extends into vitreous in infant
Neonatal oxygen supplementation for NRDS (temporary local hyperoxia upreg prod of VEGF --> retinal neovasc and detachment w/ blindness)
Cretinism
Neonates initially are asxatic due to transplacental T4 transfer. Sx: lethargy, poor feeding, hypotonia, puffy face, umbilical hernia, macroglossia
Types of hypoglycemic sx
Neurogenic - sympathoadrenal activation (norepi/epi and ach, tremulousness, palpitations), neuroglycopenic - behavioral changes, stupor, confusion, sz
Chronic haloperidol use
Neuroleptic malig syndrome - fever, AMS, muscle rigidity, autonomic instability
Sx of serotonin syndrome
Neuromuscular excitation (hyperreflexia, clonus, myoclonus, rigidity, tremor), autonomic stim (hyperthermia, tachycardia, diaphoresis, V/D), AMS (agitation and confusion)
Axonal reaction
Neuron's axon is severed, swelling of cell body, movement of nuc to periphery, dispersion of Nissl substance
Signs of irrev neuron damage (12-24 h after injury)
Neuronal body becomes shrunken, eosinophilic cytoplasm, pyknotic nuc, Nissl substance and nucleolus disappear
Argyll-Robertson pupil
Neurosyphilis: Accommodates but does not react to light
Most common s/e of vincristine
Neurotox from interfering w/ microtubule formation in neurons. Vinca alkaloids are M-phase specific agents
What causes the green color of pus and sputum in bact infections?
Neutrophil myeloperoxidase (blue-green heme based pigment mol), catalyzes prod of hypochlorous acid (bleach) during phagocytic resp burst
Common s/e of corticosteroid tx seen on CBC
Neutrophilia (promote neutrophil demargination). They reduce counts of basophils, eos, lymphocytes, and monocytes.
Which cells cause the intense inflam response in gout?
Neutrophils (phagocytose urate crystals and release cytokines that lead to PMN activation and chemotaxis). Tx of acute attack w/ NSAIDs or colchicine
What part of immune sys causes lung abscess?
Neutrophils are recruited by chemokines and release cytotoxic granules (lysosomes) containing MPO --> damage pulm parenchyma, cause liquefactive necrosis
Adrenergic and cholinergic pathways and ion changes
Nicotinic: VGCC open, ACh released, Na and Ca in and K out at endplate potential. A1-AR: IP3 (inc IC Ca). B1/B2-AR: cAMP --> PKA. M1/M3: IP3 --> PKC, M2: cAMP
Toxicity of nitroprusside
Nitroprusside is metabolized in body to release NO and cyanide ions --> cyanide toxicity. Cyanide normally metabolized in tissues by rhodanese (transfer sulfur to cyanide to form thiocyanate --> less toxic, excreted in urine)
Stable angina, unstable angina/NSTEMI, STEMI
No sx ~ <75% luminal plaque, no thrombus; stable angina ~ 80% luminal plaque, no thrombus; unstable angina ~ ulcerated plaque w/ partially obstructive thrombus; STEMI ~ ruptured plaque w/ fully obstructive thrombus
Can dopamine cross the BBB?
No, but L-DOPA can (dopamine precursor)
Do all asthmatics have elevated IgE?
No, only atopic (extrinsic allergic) asthma do. Not intrinsic asthma precipitated by aspirin, cold air, stress, exercise-induced
Do you d/c pt w/ BAC 245 mg/dL who refuses tx?
No, patient lacks adequate decision-making capacity; surrogates (close family members) should make decisions until he is sober
CXR of pulmonary silicosis
Nodular densities and eggshell calcifications of the hilar nodes, birefringent silica particles surrounded by fibrous tissue
Diagnostic serologies of syphilis
Nontreponemal (RPR, VDRL): Ab to cardiolipin-chol-lechitin Ag, lower sensitivity in early infection. Treponemal (FTA-ABS, TP-EIA): Ab to treponemal Ags, greater sensitivity in early infection
Parietal lobe syndromes
Non-dominant ~ hemi-neglect, dominant ~ Gerstmann syndrome (R-L confusion and difficulty w/ writing and math)
Temporal lobe syndromes
Non-dominant ~ nonverbal memory (musical ability), dominant ~ verbal memory (word recognition). Also Kluver-Bucy
Transformation
Non-pathogenic bacterium can uptake exogenous DNA fragments, integrate the DNA into its genome, and express the encoded proteins (non-pathogenic S pneumo acquires capsular polysaccharides)
Syndenham chorea
Non-rhythmic movements of hands, feet, and face; sudden changes in voice pitch and volume
Buspirone
Nonbenzo anxiolytic for GAD, not effective at treating acute anxiety b/c of slow onset of action (1-2 wks), partial agonist of 5-HT1A-R, no risks of tolerance
Club cell fcn
Nonciliated, secretory constituents of term resp epith. Secrete club cell secretory prot (protects against aw inflam and oxidative stress), detoxify inhaled substances by CYP450 mechanism
Thrombolytics/fibrinolytics, nonfibrin-specific vs fibrin-specific
Nonfibrin-specific ~ streptokinase, fibrin-specific ~ tPA, reteplase, tenecteplase have less systemic activation of plasmic and dec risk of bleeding. Cause reperfusion arrhythmia upon restoration of flow after clot lysis
Multicystic dysplastic kidney dz
Nonhereditary renal malformation w/ multiple noncomm cysts w/ intervening dysplastic tissue. Unilat is asxatic, bilat causes early, severe renal insuff
Digoxin tox
Nonspecific GI and neuro findings, changes in color vision, fatal cardiac arrhythmia, hyperK (sign of digoxin tox by inhibiting Na/K ATPase), hypovolemia, renal failure
Causes of hypoxemia
Normal Aa grad ~ hypovent (OHS, neuromusc d/o), low FIO2, elev Aa grad (R-to-L shunt, V/Q mismatch, diffusion impairment)
Diastolic heart failure findings (impaired relaxation, inc wall stiffness)
Normal LVEF (>50%) and LVEDV in the setting of inc LV filling pressures. Diastolic HF due to long-standing HTN causing LV wall hypertrophy
Euthyroid sick syndrome
Normal TSH, normal T4, low T3. Seen in severe systemic illness (eg, sepsis). Excess cortisol, inflam cytokines, starvation etc. reduce conversion of T4 to T3
Inc HR, inc CO, ~PaO2/PaCO2, dec PmvO2, inc PmvCO2
Normal exercise
Kid sees dead grandmother at night and speaks to her before bed
Normal grieving. No workup is necessary
What is considered a low, moderate, and high Vd?
Normal plasma vol is 3L. Thus, drug with Vd of 4.5L is almost exclusively trapped in plasma vol and is very highly bound to plasma proteins.
Pauci-immune RPGN
Normal serum C3 and C4, ANCA in their serum
Smith protein
Normally complexes w/ snRNA in cytoplasm, forming snRNPs and spliceosome. RNA pol II makes snRNA
Odynophagia in HIV pt
Normally due to Candida; in HIV can be due to Candida, HIV, CMV. Refer to Uworld Tables tab
When is the liver prone to infarction?
Normally liver has hepatic a and portal v. In transplanted liver, collateral supply severed in transplantation --> hepatic a thrombosis causes organ failure
Paroxysmal nocturnal hemoglobinuria
Normally, GPI anchors CD55/59 to RBC memb preventing C deposition. Absence of CD55/59 (mutated PIGA gene, no GPI anchor) --> MAC complexes and C-med hemolysis. Sx: fatigue, jaundice, low Hp, thrombosis at atypical sites, pancytopenia
What should be done to dx acute cholecystitis if US is inconclusive?
Nuclear medicine hepatobiliary scanning (cholescintigraphy) --> tracer is excreted into bile, but does not enter the occluded cystic duct in cholecystitis
Zinc finger (Cys-Zn-His), used by TFs
Nuclear/steroid hormone receptor. PET CAT on TV (prog, E2, T, cortisol, aldo, T3/T4, Vit D). Zinc finger is most common DNA-binding domain in humans.
Leukoerythroblastic reaction
Nucleated red cells and immature white cells, occurs when marrow is replaced by fibrosis, tear drop cells
Drug to treat VZV in pt lacking viral phosphorylating enzymes (cidofovir is nucleotide not nucleoside, and requires only cellular kinases for activation, not virally encoded kinase)
Nucleoside analog antiviral drugs must be phosphorylated into nucleotides to fcn (acyclovir, vala, famci, ganci require thymidylate kinase phosphorylation) --> use foscarnet (pyrophosphate analog viral DNA pol inhibitor that does not require viral kinase activation) or cidofovir (broad spectrum antiviral nucleotide analog of cytidine monophosphate, not nucleoside).
Xeroderma pigmenosum
Nucleotide excision repair (endonuc complex detects abnormalities in DNA structure --> endonuc complex nicks the damaged strand, excises defective region --> DNA pol synthesizes new DNA, DNA ligase seals)
Most common elbow injury in children
Nursemaid's elbow, radial head subluxation --> elbow extended and forearm pronated
Pathophys of noncommunicating (obstructive) hydrocephalus
Obstruction of CSF flow b/n ventricles and subarachnoid space --> aqueductal stenosis, Arnold-Chiari or Dandy-Walker malformations and tumors --> inc ICP (HA, N/V)
Gametogenesis
Oogonia/spermatogonia - G0, 2n (46), 2c. Primary oocyte/1° spermatocyte - prophase I, 2n (46), 4c. 2° oocyte/spermatocyte, metaphase II, 1n (23), 2c. Mature ovum, spermatid, telophase II, 1n (23), 1c
Ovarian teratomas
Occur in age 10-30, mature are benign. Age of dx of ovarian carcinoma is age 60, histo findings are sheets of tumor cells w/ irreg nuc, prominent nucleoli
Short bowel syndrome
Occurs in pts w/ massive small bowel resection or Crohn's dz --> postprandial high-vol diarrhea and wt loss, B12 def
Rare disease assumption
Odds ratio approximates RR when disease incidence is low (i.e., <10%)
Perinatal CMV
Often asxatic, but may p/w fever, pneumonitis and hepatomegaly
Appendiceal carcinoids
Often have a benign clinical course (found at tip of appendix in asxatic pts). Carcinoid tumors at base of appendix cause obstruction and appendicitis, may metastasize to liver --> carcinoid syndrome (flushing, diarrhea, bronchospasm)
Prognosis of low grade dysplasia
Often spont regresses. High grade often progresses to cancer. Dysplasia is characterized by reversibility, compared to carcinoma which is irrev
Treatment of severe asthma
Omalizumab (anti-IgE Abs given as subQ injection)
Signet cell carcinoma
One of two types of gastric adenocarcinoma, cells that do not form glands, diffuse involvement of stomach wall (loss of E-cadherin), leather-bottle stomach (linitis plastica)
Diphenoxylate
Opioid anti-diarrheal agent, binds to mu receptors in GI tract and slows motility. Co-formulated w/ atropine to discourage abuse (causes dry mouth, blurry vision, N)
IgE-indep mast cell activation (via PKA and PI3K) --> release of histamine, bradykinin, heparin
Opioids, radiocontrast agents, vancomycin
Oppositional defiant d/o vs conduct d/o
Opp defiant d/o sx are less severe than in conduct d/o, and do not include physical aggression, stealing, or destruction of property. Conduct d/o characterized by violating major societal norms and basic rights of others
Manifestations of multiple sclerosis
Optic neuritis, INO, cerebellar dysfcn (intention tremor, broad-based gait), Lhermite sign: electrical sensations in limbs or back, Uhthoff phenomenon: sx worsening w/ inc body temp (slowing of conduction in unmyelinated nerves)
Urea cycle, starting in mito
Ordinarily, careless crappers are also frivolous about urination (ornithine, carbamoyl phosphate, citrulline, aspartate, argininosuccinate, fumarate, arginine, urea
Tx of organophosphates: why atropine AND 2-PAM?
Organophosphates are irrev cholinesterase inhibitors. Atropine counters excessive muscarinic stim, but pts still at risk of nicotinic overactivation --> require pralidoxime (cholineserase reactivator)
Psoas muscle
Originates on ant surface of transverse processes of vertebral bodies of T12-L5, involved in hip flexion
Primary hyperparathyroidism
Osteitis fibrosa cystica ~ salt and pepper skull, "brown tumor" filling cystic spaces
PTH receptors are found on which cell?
Osteoblasts. PTH causes OBs to inc prod of RANKL --> stimulate RANK on OC. PTH also decreases osteoprotegrin, which is decoy receptor for RANKL.
Metastases to bone
Osteolytic (lucent) ~ due to osteoclast stimulation, tend to represent aggressive cancer. Osteoblastic (sclerotic) ~ due to osteoblasts, indicates a more indolence course
Phases of Paget dz
Osteolytic - osteoclast dominated, mixed phase - osteoclast and osteoblast, osteosclerotic - weak, thickened woven bone. Elderly pt w/ focal bone pain and pathologic fractures
Types of osteoblastic, mixed, and osteolytic cancers
Osteolytic: multiple myeloma, NSCLC, non-Hodgkin lymphoma, RCC, melanoma. Osteoblastic: prostate cancer, SCLC, Hodgkin lymphoma. Mixed: gastrointestinal, breast
Histology of acute viral hepatitis
Panlobular lymphocytic infiltrates, ballooning hepatocytes, hepatocyte necrosis, hepatocyte apoptosis
Erythema nodosum
Panniculitis (inflam of subQ fat), painful erythematous nodules in LE. Widening of CT septe due to neutrophilic infiltration and fibrin exudation, followed by histiocyte and giant cell infiltration w/ septal fibrosis
Persistence of primary spongiosa in medullary cavity
Osteopetrosis - Marble bone dz, dec osteoclastic bone resorption
Medical complications of anorexia (BMI < 18.5)
Osteoporosis, amenorrhea, lanugo, enlarged parotid glands, cardiac atrophy, cardiomyopathy, arrhythmias
S/e of loop diuretics
Ototoxicity.
Epith of female repro tract
Ovary ~ simple cuboidal, fallopian tube (ciliated - move along egg) and uterus ~ simple columnar, endocervix ~ simple columnar, ectocervix and vagina ~ strat squamous
42M w/ hx of T1DM c/o frequent involuntary loss of urine, uncontrolled voiding w/o sensation of full bladder
Overflow incontinence - incomplete emptying (detrusor underactivity or outlet obstruction). Assoc w/ polyuria (diabetes) or bladder outlet obstrution (BPH), neurogenic bladder (MS)
Cholesteatoma
Overgrowth of desquamated keratin debris w/in middle ear space --> may erode ossicles, mastoid air cells --> conductive hearing loss. Painless otorrhea
Osgood-Schlatter dz
Overuse injury of secondary ossification center of the tibial tubercle, young adolescent athletes after growth spurt. Jumping (repetitive quads contraction) separates patellar tendon from tibial plateau
Plasma cell appearance
Ovoid, abundant cytoplasm, eccentric nuc, wagon wheel, zone of perinuc clearing (active Golgi body)
Pathogenesis of centriacinar emphysema
Oxidative injury to resp bronchioles by smoking --> activation of resident alv Mos, inflam recruitment of PMNs --> activated Mos and PMNs release proteases and gen ROS to degrade ECM
Pentose phosphate pathway (oxidative/irrev and nonox/rev)
Oxidative: G6P --> 6-PG --> ribulose-5-P (depends on synthetic and oxidative burst needs), nonoxidative: ribulose-5-P to produce ribose-5-P, G-3-P, F-6-P (via transaldolases and transketolases, depends on nucleotide synthetic needs)
Histopath of eosinophilic esophagitis
P/w dysphagia and food impaction in atopic adults. Numerous superficially located intraepith eos, GERD tx does not improve sx
Causes of eosinophilia
PACCMAN (parasites, asthma, Churg-Strauss, chronic adrenal insuff, myeloprolif d/o, allergic processes, neoplasia (Hodgkin's)
Prophylaxis of HIV opportunistic infections
PCP - TMP/SMX (CD4 < 200), Toxo - TMP/SMX (CD4 < 100), MAC - azithromycin (CD4 < 50), histoplasma - itraconazole (CD4 < 150)
Which part of nephron reabsorbs majority of water in dehyd state?
PCT reabsorbs majority of water regardless of hydration state
MOA of PD1
PD1 (programmed death receptor on surface of activated T cells, binds to PD-L1 and inhibits CD8 T cells (like CDLA-4)
Cilostazol
PDE-I used in sxatic PAD (claudication). Dipyridamole and cilostazol inhibit platelet aggregation by inhibiting phosphodiesterase activity and inc cAMP; also direct arterial vasodil
ABG after PE
PE causes causes V/Q mismatch --> intrapulmonary R to L shunting --> hypoxemia stim respiratory drive, so it is ABG for hyperventilation
Most common cause of cryptogenic stroke
PFO (more common) or ASD (aplasia of septum primum or septum secundum). In times of inc RAP (Valsalva), PFO can be temporarily opened and atheroemboli cause stroke
What can cause paradoxical embolism?
PFO, ASD, VSD, large pulmonary AVF. ASD causes wide/fixed splitting of S2
Effect of PK def on the spleen
PK def --> insuff ATP prod --> water and K loss from RBC --> hemolysis is cleaned by RES cells (in red pulp) --> red pulp hyperplasia and splenomegaly
What are the protein kinases?
PKA, PKB (Akt - serine/threonine specific protein kinase), PKC
Chediak Higashi
PLAIN: Progressive neurodegen, lymphohistiocytosis, albinism (partial), recurrent pyogenic infections by Staph and Strep, peripheral neuropathy. Dysfcn of phagosome-lysosome fusion
Edwards (Trisomy 18)
PRINCE Edward (Prominent occiput, rocker-bottom feet, intellectual disability, nondisjcn, clenched fists, low-set ears), micrognathia, cong heart dz, low-set ears, omphalocele
Most common cause of acute pediatric GN
PSGN. Increased age is poor prognostic factor (chronic HTN, recurrent proteinuria, CKD, RPGN). C3 dec in PSGN due to C deposition in glom
Diseases w/ psammoma bodies
PSaMMoma bodies: Papillary thyroid cancer, serous papillary cystadenocarcinoma of the ovary, meningioma, malignant mesothelioma
Which substance increases serum Ca and urine PO4, PTH or Vit D?
PTH inc renal dumping of PO4. Vit D increases Ca reabsorption and gut absorption of Ca, which will feedback-inhibit PTH and prevent phosphaturia
Berger disease (IgA nephropathy)
Painless hematuria in children and young adults a few days after a URI
Splenic artery branches
Panc branches - run post to upper border of panc, supplying body and tail. L gastroepiploic a - supply middle part of greater curvature of stomach. Short gastrics - upper part of gr curvature
Risk factors for cancer
Pancreatic cancer ~ tobacco smoke, obesity; renal ~ smoking, obesity; colorectal ~ hereditary CRC syndrome, IBD, obesity, charred foods; bladder ~ tobacco smoke, rubber, aniline dyes
Mechanism of B12 def in chronic pancreatic insuff
Pancreatic enzymes normally cleave R factor from B12, allowing B12 to bind to IF and be absorbed
Aplastic anemia
Pancytopenia without splenomegaly (absence of splenomegaly is key!). Other causes of pancytopenia w/o splenomegaly are severe B12/B9 def, acute leukemia, MDS
Which tissue are vertebrae derived from?
Paraxial mesoderm
Order of cardiac tissue conduction velocity
Park AT Venture AVenue - Purkinje, atrial muscle, ventricular muscle, AV node
Signs of binge eating/purging subtype of anorexia, VS BULIMIA
Parotid gland hypertrophy, dental caries, halitosis, calluses on dorsum of hands (Russell sign). BULIMIA - MAINTAIN BODY WT >= NORMAL, NO MALNUTRITION/STARVATION
4 parts of Medicare
Part A: HospitAl insurance, hospice; Part B: Basic medical Bills, Part C: Combo/Capitated (parts A+B) delivered by private Companies, Part D: prescription Drugs
Presentation of ovarian cancer
Pelvic mass, ascites, peritoneal metastasis resulting in dec appetite, abd distension, bowel/bladder changes (constipation, urinary frequency)
Is oral/mucosal involv in pemp vulg or bul pemp? How about in elderly?
Pemp vulg has oral/mucosal involvement, bullous pemp in elderly
LMWH vs UFH MOA
Pentasaccharide sequence binds AT III, which stops FXa from converting prothrombin to thrombin. UFH is able to bind both FXa and thrombin
Hawthorne effect
People modify their behavior if they know they are being observed
Detection bias
People who smoke undergo more extensive surveillance than nonsmokers
What activates pepsin?
Pepsinogen released by chief cells of stomach, activated by HCl in the stomach
Human placental lactogen
Peptide hormone secreted by syncytiotrophoblast, inc in maternal insulin resistance in 2nd and 3rd trimesters --> ensures supply of glu and AA to fetus. Also inc maternal lipolysis and stimulates panc beta-cell insulin prod
CVS
Performed at 10-14 weeks gestation, risk of miscarriage and infection, can sequence the fetal DNA
S/e of CCB
Peripheral edema (preferential dilation of precap arterioles), dizziness, lightheadedness
Charcot-Leyden crystals in stool
Peripheral eosinophil breakdown (similar to asthma), seen in intestinal parasitic infections
R paracolic gutter
Peritoneal recess b/n ascending colon and abd wall. Fluid (bile/pus/blood) accum there from pathology involving GI organs, esp appendix and gallbladder
Acute graft rejection of lung
Perivasc mononuc infiltrate in small BVs of lung, which expand to include alv walls
Pathophys of MS
Perivenular inflam infiltrates made up primary of autoreactive T lymphocytes and Mo directed against myelin components
X-linked adrenoleukodystrophy
Peroxisomal dz, defective transport of VLCFAs into peroxisomes --> neuro degen in childhood and adrenal insuff
Where are VLCFA and phytanic acid oxidized?
Peroxisome, not mito (cannot undergo beta-ox)
Failure of omphalomesenteric (vitelline duct) obliteration
Persistent vitelline duct/vitelline fistula (meconium d/c from umbilicus at birth), Meckel diverticulum, vitelline sinus, vitelline duct cyst (enterocyst)
Phrenic nerve irritation vs palsy
Phrenic nerve irritation - dyspnea, hiccups referred pain to shoulder. Palsy - resp distress, diminished breath sounds on affected side, elev of hemidiaphragm
Types of dead spaces
Physiologic dead space = anatomic dead space (of conducting aws, 150 mL) + alveolar dead space (well-ventilated, poorly perfused alveoli). TACO PACO PECO PACO
Stab wound at the L sternal border, 4th ICS
Pierces RV
Most common brain tumor in children
Pilocytic astrocytoma. Heterogeneous, well-circumscribed cerebellar mass. Cystic, unlike medulloblastoma which is always in cerebellum and solid. Pilo astro is most common brain tumor in children, medulloblastoma is most common malig brain tumor in children
Which muscle occupies most of the space in gr sciatic foramen?
Piriformis, above are sup glut vessels and n, below are inf glut vessels, int pudendal vessels, sciatic nerve. Piriformis syndrome: piriformis hypertrophy --> sciatica like pain
Central DI due to hypo vs pit damage
Pit damage - transient central DI, as hypo nuc are intact and axonal regen can allow adequate ADH release. Hypo - permanent central DI
Genetic transition
Point mutation that results in the replacement of a purine nucleotide for another purine, or pyrimidine for pyrimidine. Transversion - pur for pyr, vice versa
Differentiate ambiguous genitalia from 21-OH def vs aromatase def
Placental aromatase def - inc T and androstenedione, dec estrone and estrogen, maternal virilization common. No maternal virilization in 21-OH def b/c placental aromatase is intact
Podophyllin
Plant alkaloid that targets topoisomerase II, used topically to treat genital warts. Related to etoposide
Hemostasis
Platelets attach to exposed Col via Gp1b binding to vWF --> release of ADP/TXA2 to activate other platelets --> GP Iib/IIIa binding to fibrinogen (platelet plug)
Developmental milestones at age 3
Play imaginatively in parallel, speak in simple sentences, copy a circle, use utensils, ride a tricycle
How are MTX, DHF, and THF stored in the cell?
Polyglutamylation
Medullary thyroid cancer
Polygonal or spindle shaped cells w/ slightly granular cytoplasm that stains for calcitonin, extracellular amyloid deposits (Congo red +ve)
Presentation of TEF
Polyhydramnios (inability of fetus to swallow amniotic fluid), drooling (inability to swallow saliva), choking, coughing, cyanosis w/ feeds (reflux into lungs). X-ray shows stomach bubble (resulting from air flow from trachea thru fistula into distal esophagus)
Virulence factor of H flu type b
Polyribosylribitol phosphate capsule. Protects bacterium from phagocytosis and C-med lysis by binding factor H, a circ reg prot that normally prevents C3b deposition on host cells
Why is HiB vaccine conjugated to tetanus toxoid?
Polysaccharide vaccine only does not elicit lasting immune response b/c the neonate's humoral immunity is immature. Toxoid vaccine elicits B and T cell response.
Injury to base of pons? To caudate nucleus?
Pons - contralat weakness and ataxia due to injury to corticospinal/corticobulbar/pontocerebellar, caudate - behavioral abnormalities (agitation, psychosis, abulia), choreoathetosis
Effect of poor maternal glucose control on neonatal hypoglycemia
Poor maternal glucose control --> excessive transplacental glucose to the fetus --> stimulates fetal insulin prod --> beta-cell hyperplasia and hyperinsulinism --> inc fat deposition, macrosomia
Problems that occur in popliteal fossa
Popliteal artery aneurysms, Baker cysts (assoc w/ arthritis). Small saphenous v found at lat aspect of foot
What is the most common d/o of heme synthesis?
Porphyria cutanea tarda, assoc w/ Hep C. Photosensitivity is late-stage, after sufficient accum of porphyrinogens
Which compound causes photosensitivity in heme syn d/o's?
Porphyrinogens/porphyrins. Thus, ALAD and PBG deaminase (AIP) deficiencies do not cause photosensitivity
What does +ve vs -ve sense mean for RNA viruses?
Pos sense can be directly translated into proteins, negative sense must first convert RNA
Naïve T cells (Th0)
Possess TCR and CD3 and CD4 on their cell surface. Ag-MHC II complex is presented to naïve T cell by APC. If APC is Mo, Mo prod IL-12 and stim diff into Th1. All other APCs prod IL-4 and stim diff into Th2.
Peptic ulcers located where are more likely to bleed?
Posterior duod ulcers more likely to bleed (from gastroduod artery), ant duod ulcers more likely to perforate
Location of the locus cerelleus
Posterior rostral pons near lateral floor of 4th ventricle
Most common cause of bilat fetal hydronephrosis
Posterior urethral valves - obstructive, persistent urogenital membrane at vesiculoureteral jcn
Posterior nosebleeds
Posterolateral branches of sphenopalatine a, more severe, cannot be treated w/ cautery
Sharp and pleuritic pain 4 d post-MI, and significance of sx
Postinfarction fibrinous pericarditis (reaction to the transmural necrosis). Exacerbation w/ swallowing ~ posterior, radiation into neck ~ inferior pericardium
Pathogenesis of prion proteins
PrP has change in secondary structure that renders it resistant to enzymatic digestion by proteases
Multiple logistic regression
Predict the probability of a binary outcome (presence or absence of gastric cancer) based on >=1 independent variables
WPW
Preexcitation syndrome, short PR interval, delta wave at start of QRS, wide QRS
Conditions assoc w/ carpal tunnel syndrome
Pregnancy (fluid accum), hypothyroidism (GAG buildup), DM (CT thickening), RA (tendon inflam), hemodialysis (b2-microglobulin deposition)
IL-4
Prod by Th2 cells and activates B cells, induces IgE isotope switching, and promotes Th2 cell differentiation
Risks of secondhand smoke exposure
Prematurity, low birth weight, SIDS (unexpected death of healthy infant during sleep), middle ear dz (otitis media), asthma, resp tract infections (bronchitis, pneumonia)
ADHD criteria
Presence of sx before age 12 and >=6 inattentive and/or hyperactive/impulsive sx
TCAs (amitriptaline and venlafaxine)
Presynaptic serotonin and norepinephrine reuptake inhibition
Advantage of steroids in tx of CAP/HAP/VAP
Pretx w/ dex reduces the levels of inflam cytokines (that are components of the lysed S pneumo cell wall) in the CSF and limits the risk of inflam-induced morbidity
Postpartum psychosis
Prevalence 0.1-0.2%, onset days to weeks, sx: delusions, hallucinations, thought disorganization, bizarre behavior, management: hospitalization (risk of infanticide), antipsychotics, antidep, mood stabilizers
Postpartum blues
Prevalence 40-80%, onset 2-3 d, resolves w/in 14 d, sx: mild depression, tearfulness, irritability, management: reassurance
Bacitracin
Prevents mucopeptide transfer into bacterial cell wall --> inhibits bacterial cell wall syn
Primary vs secondary intention healing
Primary - surgical closure of well-approximated wound edges, less likely to scar. Secondary - spont healing is more likely to scar
HHV8 causes which lymphoma?
Primary effusion lymphoma - arising from B cells. Large cells, big nuc, prominent nucleoli
Pathway of aqueous humor flow
Prod by epith cells of ciliary body --> flows through pupil into ant chamber --> diffuses thru trabecular network --> enters canal of Schlemm --> drains into veins
Autoimmune hemolytic anemia (AIHA)
Prod of Abs against RBCs, occurs following infection by Mycoplasma pneumoniae and EBV
Uremic platelet dysfcn
Pts w/ sig renal dysfcn accum uremic toxins in circ --> toxins impair platelet aggregation and adhesion --> prolonged bleeding time, ~PT/PTT, ~Plt count. Tx: dialysis
Does 1° or 2° adrenal insuff cause hyperpigmentation?
Primary! Autoimmune destruction of adrenal feeds back to inc ACTH and cause POMC transcription, thus producing MSH
Large intracytoplasmic vacuoles (spongiform)
Prion disease (rapidly progressive dementia and myoclonus)
What is PrP?
Prion protein. Normally found in neurons in alpha-helix --> conversion to beta-pleated sheet causes accum in grey matter --> prion dz
Coronary-subclavian steal syndrome
Prior coronary a bypass using int mammary a. Blood flow thru IMA can reverse and steal flow from coronary circ during exercise --> angina pectoris
Absolute contraindications of OCPs
Prior hx of thromboembolic event or stroke, hx of estrogen-dep tumor, smokers over age 35, hyperTGemia, decompensated or active liver dz (impaired steroid metabolism), pregnancy
T cell maturation
Pro T cells arrive from BM to thymus as double negative --> TCR beta gene arrangement (double positive CD4+/CD8+) --> +ve selection --> -ve selection
Which drug is used to block renal tubular excretion of penicillins/cephalosporins and prolong their half life?
Probenecid
Activation of tamoxifen
Prodrug tamoxifen is metabolized by CYP2D to its active metabolite, endoxifen
Hypoxic-ischemic encephalopathy
Profound systemic hypotension (cardiac arrest or shock) causes global cerebral ischemia, neurons don't store glycogen --> permanent damage after 4-5 min. Dec consciousness (coma, vegetative state)
Arginase deficiency
Prog development of spastic diplegia, abnml movements, growth delay, elev arginine levels, mild or no hyperammonemia. Tx: low prot diet devoid of arginine
Pt w/ longstanding heartburn p/w inc substernal burning unresponsive to antacids
Progression of GERD to erosive esophagitis and formation of ulcer
Hypertensive encephalopathy
Progressive HA, vomiting, confusion (non-localizing neuro sx), coma, death. Brain edema, petechial hemorrhages throughout grey and white matter
Biliary atresia
Progressive complete or partial obstruction of extrahepatic bile ducts. Biliary tree normal at birth but undergoes immune/viral destruction by age 2 mo. Dark urine, acholic stools, elev Dbili. Histology: intrahepatic bile duct prolif, portal tract edema, fibrosis
Restrictive cardiomyopathy w/ diastolic HF
Progressive exertional dyspnea, edema, ascites, elev JVP, rapid y descent, prominent S4. Due to idiopathic, amyloidosis, sarcoid, hemochromatosis, radiation fibrosis, endomyocardial fibrosis. Normal myocardial cells with areas of amorphous, acellular pink mat'l infiltration
Cytoplasmic inclusions in oligodendrocytes
Progressive multifocal leukoencephalopathy
Visceral leishmaniasis (kala-azar)
Progressive splenic enlargement and wt loss over months
Placental site trophoblastic tumor
Prolif of intermediate trophoblasts, produces hPL
Sirolimus
Prolif signal inhibitor targeting mTOR signaling pathway. Binds immunophilin FK-506 binding protein, forming complex that inhibits mTOR --> interrupts IL-2 signal transduction, prevent G1-o-S phase prod
Pelvic floor injury
Prolonged second stage of labor, multiple deliveries, hysterectomy --> disruption of levator ani muscles causes urethral hypermobility
TATA and CAAT boxes in eukaryotes
Promoters - initiators of transcription, upstream of transcription start site, site where RNA pol II and other transcription factors bind DNA
Why does warfarin therapy cause a procoagulant state at first?
Protein C and S are Vit K dependent, and are first to be depleted in warfarin therapy b/c of short half life. Start warfarin w/ heparin or LMWH
Calcineurin
Protein phosphatase that dephosphorylates nuclear factor of activated T cells --> NFAT enters nuc, binds IL-2 --> IL-2 stim growth and differentiation of T cells
Which muscle is most important to achieve Valsalva?
Rectus abdominis
Pain on extension of the hip
Psoas sign (pt positions themselves at rest to minimize psoas discomfort, namely hip flexion)
Lucid interval of epidural hematoma
Pt loses consciousness at time of impact, but quickly regains consciousness and feels well for a few hrs --> followed by quick decline in mental fcn to coma and death
In which patients is the a-wave absent? In whom is it prominent?
Pts w/ a-fib have loss of a-wave. Prominent a-wave in hypertrophic cardiomyopathy pts
Slow onset malaise and cough in smoker w/ dental caries
Pulmonary actinomycosis due to aspiration --> lower lobe consolidation w/ air bronchograms (air-filled bronchi surrounded by alv opacification). Yellow sulfur granules look purple/blue on H&E
TPAVR
Pulmonary and systemic venous systems flow into R atrium --> RA and RV dilation. There is obligatory R to L atrial shunting.
How to distinguish sarcoid from other ILD (hypersensitivity pneumonitis, cryptogenic organizing pneumonia, lymphocytic interstitial pneumonitis)
Pulmonary sarcoidosis is characterized by accum of CD4+ T cells, so high CD4+/CD8+ ratio (>2:1) in BAL fluid suggests sarcoid. CD8+ cells predominate in BAL fluid of pt w/ hypersensitivity pneumonitis
Amiodarone toxicity
Pulmonary tox, thyroid dysfcn, cardiac arrhythmias, elev liver enzymes, visual disturbances
Restore fertility in women w/ hypogonadotropic, hypogonadal anovulation
Pulsatile GnRH
Which brain region has pure sensory? Pure motor?
Pure sensory - thalamus. Pure motor - ant 2/3rd of post limb of internal capsule
Sural nerve
Pure sensory, posterolat leg and lat foot
Disseminated gonococcal infection and septic arthritis (young pts)
Purulent arthritis or triad of polyarthralgia, dermatitis (vesicopust lesions on extremities), tenosynovitis
Putamen
Putamen - medial to insula, lateral to internal capsule (forms C). Internal capsule - white matter that separates globus pallidus and putamen from caudate. Caudate - medial to internal capsule, affected in HD. Amygdala - medial temporal lobe
Which cells are most vulnerable to hypoxic injury in brain?
Pyramidal cells of hippocampus and Purkinje cells of cerebellum ("vulnerable hippos")
Osmotic demyelination syndrome
Quadriplegia due to demyelination of corticospinal tracts, pseudobulbar palsy due to demyelination of corticobulbar tracts of CN 9, 10, 11 --> head and neck muscle weakness, dysphagia, dysarthria
Sodium cyanide-nitroprusside test
Qualitative screening test that detects presence of urinary cysteine. Tx of cystinuria is inc hydration and urinary alkalinization (acetazolamide)
What is being detected by RT-PCR?
Quantify levels of mRNA in a sample. Cannot detect proteins or regions of DNA that are not transcribed (promoter, enhancer)
First line treatments for bipolar (other than lithium and valproate)
Quetiapine
Which antiarrhythmics are assoc w/ LQTS?
Quinidine and sotalol. Other drugs assoc w/ LQTS are abx (macrolides, fluoroquinolones), methadone, antipsychotics (haloperidol)
Presentation of R vs L sided colon cancer
R sided - exophytic masses, ascending colon has larger caliber, p/w IDA sx (fatigue, pallor, occult blood loss). L sided - infiltrate intestinal wall and encircle lumen, constipation, obstructive sx (abd pain, distension, N/V). Rectosigmoid involvement causes hematochezia
Occlusions in arteries and what they affect
RCA ~ inf wall of LV (II, III, aVF), LAD ~ anteroseptal transmural ischemia (V1-4), LCx ~ lat wall of LV (I, aVL, V5-6)
Postpartum ovarian v thrombosis
RFs: Venous stasis, hypercoag (hormonally med inc in clotting factors), endoth damage (intrapartum vasc injury). Clin features: persistent fever after delivery, localized abd/flank pain, no response to abx
Telomerase
RNA-dependent DNA polymerase, 2 subunits (TERT and TERC). Critical shortening of telomeres is signal for apoptosis (think Bloom syndrome)
Wrist drop
Radial nerve injury (innerv most forearm extensors and most hand extensors at wrist)
Atrial fibrillation
Rapid electrical impulses originating in the pulmonary veins
Mallory-Weiss tear is due to what?
Rapid inc in intraabd pres due to vomiting --> longitudinal mucosal tear at GEJ, assoc w/ alcoholism, hiatal hernias found in 50% of pts w/ M-W tears, can lead to hematemesis
Clues to psychogenic vs vasculogenic impotence
Rapid onset, preservation of spontaneous erections during sleep
Pure red cell aplasia (PRCA)
Rare form of marrow failure w/ severe hypoplasia of marrow erythroid elements, normal WBC and platelets. Assoc w/ THYMOMA, lymphocytic leukemias, parvo infection. Inhibition of erythropoietic precursors and progenitors by IgG autoAbs or CD8 T cells
Rate vs rhythm control
Rate - AV nodal blocking drugs (BB, CCB) vs rhythm control - antiarrhythmic drugs (sotalol, flecainide, amiodarone)
G6PD
Rate limiting step of pentose phosphate pathway, production of NADPH and erythrocyte antioxidant system
Measure of bone turnover
Ratio of OPG to RANK-L (higher = blastic, lower = clastic). Estrogen induces prod of OPG in premenopausal women. Denosumab is an analog of OPG (binds up RANK-L, used in postmenopausal women)
SCN
Receive input directly from retina, regulate circardian rhythms by relaying light info to other hypo nuc and pineal
Insulin signaling pathway
Receptor autophosphorylation --> phosphorylation of IRS-1 --> activation of MAPK/RAS (cell growth, DNA syn) and PI3K (transloc of GLU4) --> protein phosphatase (dephosphorylate and activate glycogen synthase)
C3 deficiency
Recurrent infections w/ encapsulated organisms
12F w/ recurrent fever and abd pain, renal scarring on imaging
Recurrent pyelonephritis from retrograde flow of infected urine from bladder into ureter. Normally ureters travel thru bladder wall at oblique angle --> flap-valve mechanism doesn't work if ureters enter bladder at perpendicular angle (vesicoureteral reflux)
XLA
Recurrent pyogenic (encapsulated) bacterial infections, failure to thrive, low Ig levels. BTK mut causes failure of BM pre-B cells to mature and develop. Bacterial infections b/c lack of opsonizing Abs, enterovirus and Giardia infections due to lack of neutralizing Abs
Selective IgA deficiency
Recurrent sinopulmonary and GI infections, autoimmune (celiac is concurrent), anaphylaxis during transfusions. C/w C1 inhibitor def, which causes hereditary angioedema w/ transfusions
Leukocyte adhesion deficiency (absence of CD18 - form integrins)
Recurrent skin and mucosal bacterial infections, no pus, delayed umbilical cord separation, MARKED PERIPHERAL LEUKOCYTOSIS W/ NEUTROPHILIA
Reaction formation
Redirection of an unacceptable feeling to the opposite (instead of being angry, pt behaves overly affectionate)
Intrapulmonary shunting in PE
Redistribution of blood flow away from area affected by clot, and areas distal to clot have high V but low Q.
Nephrotoxic effects of cyclosporine/Tacrolimus
Reduce RBF, cause direct damage to renal endothelial and tubular cells --> arteriolar hyalinization and tubular vacuolization
Restrictive lung diseases
Reduced DLCO - intrinsic lung disease (ILD), normal DLCO - extrinsic (obesity, neuromuscular)
Prolonged nitrous oxide exposure
Reduced methionine synthase activity --> megaloblastic anemia
Most common destinations of metastases
Regional LNs, liver, lungs, skel sys (via hematogenous spread)
What drives the formation of caseating cavitations in TB?
Release of proteases, NO, and ROS from multinucleated giant cells and epitheloid histiocytes (i.e., aggregations of activated leukocytes)
Tryptase
Released by mast cells in Type I hypersensitivity
Which proteins bind to the ribosome when stop codon encountered?
Releasing factors (RF1) - stimulate release of formed polypeptide
Iodotyrosine deiodinase
Removes iodine groups from MIT and DIT for recycling
Factors that increase PRA
Renal artery stenosis, low sodium intake, diuretics (HCTZ), ACE-I, ARB
Flank pain, hematuria, elev LDH (cell necrosis), wedge shaped kidney lesion
Renal infarction. Most common cause of renal infarction is systemic thromboembolism from LA or LV. Most common cause of systemic TE is a-fib
Recent dx of membranous nephropathy p/w flank pain, hematuria, L varicocele
Renal vein thrombosis 2° to nephrotic syndrome --> inc glom wall permeability in nephrotic syndrome leads to loss of ATIII --> hypercoag state
Chronic sickle cell dz does what to the spleen?
Repeated infarction leads to scarring, fibrosis and atrophy
Pygmalion effect
Researcher's beliefs about efficacy of tx can affect outcome, by teacher facilitating success differentially
CXR findings of pulmonary berylliosis
Resembles sarcoidosis (nodular infiltrates, enlarged LNs, noncaseating granulomas)
Decreased activity of intracellular catalase peroxidase
Resistance to INH (this drug inhibits mycolic acid syn by M tb). Resistance can also be due to genetic modification of INH binding site on mycolic acid synthesis enzyme
Extraskeletal sx of ank spond
Resp - limited chest wall expansion, CV - ascending aortitis, eye - ant uveitis
Pathway of Neisseria meningitis
Resp droplets to nasopharynx --> bloodstream --> choroid plexus --> meninges
Presentation of chronic bronchitis
Resp failure, hypoxia, thickened bronchial walls, neutrophilic infiltrates, mucous gland enlargement, squamous metaplasia
Where does HPV infect other than the genitalia?
Respiratory papillomatosis - true vocal folds have stratified squamous epith (undergo constant friction for speech). NOT false vocal folds (ciliated, pseudostratified columnar)
Resting tremor vs rubral tremor
Resting tremor - parkinsonism, damage to STN. Rubral - occurs at rest and during goal-directed activity, damage to midbrain, SN, SCP
Rebound rhinorrhea
Rhinitis medicamentosa - nasal congestion w/o cough, sneezing, or postnasal drip due to tachyphylaxis of alpha-agonist decongestant (>=3 d use). Solution: stop use of adrenergic agonists to allow restoration of normal norepi feedback
Viral bronchiolitis
Rhinorrhea and congestion followed by cough, low-grade fever, inc work of breathing, tachypnea, retractions w/ diffuse wheezes and crackles
Stool findings in cholera
Rice water stool (flecks of mucus and sloughed epithelial cells), NOT leukocytes or erythrocytes b/c Vibrio cholera does not invade mucosa
Dense fibrous tissue extending beyond the thyroid capsule
Riedel thyroiditis - extensive fibrosis of thyroid gland extending into surrounding structures. Hard and fixed to surrounding structures, resembling malig
Structural alterations of enzymes involved in RNA syn
Rifampin resistance
S/e of TB drugs
Rifampin ~ GI s/e, rash, orange body fluids, cytopenias; INH ~ neurotox (give B6), hepatotox; pyrazinamide ~ hepatotox, hyperuricemia; ethambutol (inhibition of arabinosyl transferase) ~ optic neuropathy
When does the opening snap of mitral stenosis occur?
Right after mitral valve opening - fusion of mitral valve leaflet tips are abruptly halted during opening
Coronary dominance
Right dominant (70%) - PDA comes from RCA, L dominant (10%) - PDA comes from LCx, codominant (20%) - both RCA and LCx
Myelodysplastic syndrome
Ringed sideroblasts, pseudo-Pelger-Huet cells, petechiae, weakness, recurrent infections, no splenomegaly, defect in cell maturation of nonlymphoid lineages
What is the utility of CEA in the context of colon cancer?
Rising CEA levels are a sensitive indicator of cancer recurrence (not stage, grade, initial screening, or dx!)
Ristocetin aggregation test
Ristocetin activates vWF to bind GpIb --> failure of aggregation w/ ristocetin assay occurs in vWD and Bernard-Soulier syndrome
Dense lymphocytic infiltrate of melanoma
Robust immune response, improved prognosis
Patau (Trisomy 13)
Rocker bottom feet, intellectual disability, cleft lip/palate, holoprosencephaly, polydactyly, cutis aplasia (punched out lesion on scalp), PKD, cong heart dz. NOT assoc w/ overlapping fingers
First step after a series of med errors in hospital
Root cause analysis (interview pharmacy, nursing, and medical staff on the units where it occurred)
Pilocytic astrocytoma
Rosenthal fibers (eosinophilic, corkscrew fibers), spindle cells w/ hair-like glial processes assoc w/ microcysts
Biofilm producing organisms
S epidermidis (prosthetic devices, IV cath), S mutans/sanguis (dental plaques), Pseudomonas (CF pneumonia, contact lenses), Viridans (endocarditis), H flu (otitis media)
Most common cause of bacterial meningitis in all adults
S pneumo (second is Neisseria). Staph aureus in pts w/ penetrating skull injury or neurosurgery
Loss of sensation in the perineal area
Saddle anesthesia - due to epidural cord compression from a malignancy. Urinary retention late, fecal incontinence
Raw egg consumption
Salmonella gastroenteritis
Composition of pancreatic juice
Same Na and K as in plasma, higher HCO3, lower Cl
Propionic acidemia
Same sx as methylmalonic acidemia w/o elev urinary MMA (hyperammonemia, hypoglycemia, metabolic acidosis). Tx: start diet w/ low valine, isoleucine, methionine, threonine
35F, Black, arthralgias, erythema nodosum, elev serum ACE
Sarcoidosis
Why does PAH extraction ratio drop at high [PAH]?
Saturation of carrier transporters that secrete PAH. Excretion can never be saturated b/c excretion = filtration + secretion - reabsorption, and filtration can never be saturated
What type of Col is scar tissue? Granulation tissue?
Scar tissue - Col I, granulation - Col III (seen 7 d after acute MI, replaced by Col I chronically)
Schizophrenia vs schizoaffective d/o
Schizophrenia lacks sig mood sx (that meet criteriafor manic or depressive episodes)
What are cutaneous neurofibromas made of?
Schwann cells - derived from neural crest. Found in NF1 (AD)
Lymphatic drainage of scrotum vs testes
Scrotum - superficial inguinal, testes - para-aortic/retroperitoneal
Complications of SAH (nimopine - selective CCB prescribed to prevent vasospasm)
Secondary arterial vasospasm in vessels surrounding ruptured aneurysm --> cerebral ischemia --> new onset focal neuro deficit/confusion 4-12 d after initial injury. Most dangerous complication of SAH is rebleeding (sudden HA, N/V etc.)
Photoaging
Seen by age 30-35, gradual thinning of epidermis. Rete ridges flattened, inc Col crosslinking --> atrophic dermis and crosslinked Col produces wrinkles
Double bubble sign
Seen in duodenal atresia, two bubbles in stomach and prox duod pouch
Scurvy
Seen in homeless, etoh or drug abusers. Easy bruising, mucosal bleeding, perifollicular petechial hemorrhages, periodontal dz, poor wound healing
Two phases of contact dermatitis to urushiol
Sensitization phase - creation of hapten-specific T cells, takes 10-14 d. Langerhans cells take up urushiol, express on MHC I/II, go to LN --> activation and clonal expansion. Elicitation phase - 2-3 d after reexposure to same Ag, activation of hapten-sensitized T cells in dermis and epidermis --> sx
Golgi tendon organs (too much force in muscle --> GTOs cause sudden relaxation, preventing damage)
Sensory receptors at junction of muscle and tendon, innerv by group Ib sensory axons, in series w/ contracting extrafusal skel muscle fibers. Sensitive to inc in FORCE, not changes in muscle length (b/c lengthening is in myofibers and not tendon)
Wedge shaped pulm infarcts in IVDU
Septic pulm emboli 2° to tricuspid valve endocarditis
Protective mechanisms to prevent premature trypsin activation
Serine peptidase inhibitor Kazal-type 1 (SPINK1) secreted by panc acinar cells, acts as trypsin inhibitor. Trypsin also cleaves active trypsin mols at second site to inactivate them
Chest pain in SLE pt
Serositis (acute pericarditis). Pericarditis pain inc on inspiration (pleuritic) and is relieved by sitting up/leaning forward (postural)
Tetrahydrobiopterin is a cofactor for synthesis of what?
Serotonin, tyrosine, and DOPA. (Phenylketonuria can be due to phenylalanine hydroxylase def, or BH4 def --> low serotonin, phenylalanine accum)
Scapular winging, failure to abduct arm above horizontal
Serratus ant injury after mastectomy w/ axillary LN removal
Which muscle lies in the 4th-5th ICS in the midaxillary line?
Serratus anterior, intercostal muscles, parietal pleura. Must pass thru these to place chest tube to drain empyema
Inhibin B is produced by what cells?
Sertoli cells. Inhibin B low in pts w/ 1 testicle (mass of Sertoli cells greatly reduced)
Which marker reflects activity of osteoblasts?
Serum bone-specific ALP. ALP prod by bone, liver, placenta, intestine. Tartrate-resistant acid phosphatase, urinary hydroxyproline, and urinary deoxypyridinoline used to measure osteoclastic activity
How does acute Hep B infection present?
Serum sickness like syndrome - joint pain, lymphadenopathy, pruritic urticarial vasculitis rash, RUQ pain, hepatomegaly, elev LFTs
Types of coarct of aorta
Severe - presents in infancy, differential cyanosis affecting LE as long as ductus arteriosus is patent. Moderate - presents in childhood w/ sx of LE claudication, BP discrepancy b/n upper and lower extremities, delayed or diminished femoral pulses, cont murmurs, pulsatile intercostal collaterals
Duration of action of common benzos
Short (<6 h): triazolam, oxazepam, midazolam. Intermediate (6-24 h): alprazolam, lorazepam, temazepam. Long (>24 h): diazepam, chlordiazepoxide, flurazepam.
Phenylketonuria
Severe mental retardation, hx of sz, abnormal pallor of substantia nira, locus cerelleus, hypopigmentation of skin/hair/eyes, musty/mousy body odor
Ureaplasma urealyticum
Sexually transmitted types of urethritis
Trochanteric bursitis
Sharp, intermittent pain at lat hip and thigh. Pain inc w/ pres on affected hip (lying on side) and w/ walking. Restricted jt movement not found
Pericardial knock vs S3
Sharper, more accentuated sound heard earlier in diastole than S3, because ventricular compliance is reduced via an external force
Which organisms have the lowest ID50?
Shigella, Campy, E histolytica, Giardia
Why are deep tissue burns rare in lightning strike but superficial are common?
Short duration of electrical contact, and "flashover effect" (lightning travels along skin surface and discharges into ground)
Which artery is susceptible to ischemic injury after splenic a block?
Short gastrics. Tissue supplied by L gastroepiploic has strong anastomosis w/ R gastroepiploic
Zolpidem
Short-acting hypnotic agent structurally unrelated to benzos, but binds to same region of GABA_A receptor and inc GABA action. Metabolized by liver CYP450
Fenoldopam
Short-acting peripheral dopamine-1 receptor agonist. Used in hypertensive emergency, causes renal vasodil (prevents AKI)
Alpha thal
Shortage of alpha globin chains. All hemoglobin is either HbH (b4) or hemoglobin Barts (g4). HbH - chronic hemolytic anemia. HbB - hydrops fetalis
Irreversible neuronal injury
Shrinkage of neuronal body, deep eosinophilia of cyto, pyknosis of nuc, loss of Nissl substance
What blood cell disease can isoniazid (latent TB tx) cause?
Sideroblastic anemia. Isoniazid directly inhibits pyridoxine phosphokinase (converts B6 to its active form). Active B6 is cofactor for ALAS (enzyme that catalyzes RLS in heme syn) --> microcytic, hypochromic anemia
PPAR family
Sig role in pathogenesis of metabolic syndrome (obesity, HTN, dyslipidemia, insulin resistance). PPAR-alpha ~ fibrates, PPAR-g ~ TZD
Causes of atopic dermatitis
Skin barrier abnormalities, defects in innate immunity, and Th2-skewed immune response
Breast cancer pathologies
Skin dimpling ~ suspensory ligaments (invasive ductal carcinoma), peau d orange ~ invasion of lymphatic spaces (inflam breast cancer), eczema of nipple ~ Paget dz (lactiferous sinus invasion)
Acrochorda
Skin tags, pedunculated outgrowths of normal skin, in areas of frequent friction (axillary, inframammary)
How do beta blockers affect an EKG?
Slow AV nodal conduction --> prolong PR interval
Partial nephrogenic DI
Slow but steady rise in urine osmolality w/ inc sodium osmolarity after water deprivation, no further inc in urine osmolality w/ DDAVP
Meningioma
Slow growing, extra-axial tumors that arise from meningothelial cells of arachnoid. Cells in lobules and whorls w/ or w/o Psammoma bodies
Phase 4 pacemaker potential
Slow influx of Na (funny current) and slow dec in K efflux as K chan close from Phase 3. As memb pot reaches -50 mV, T type Ca chan open. Trigger AP at -40 mV
Adamantinomatous craniopharyngioma
Slow-growing, benign tumors, children, suprasellar region. Cystic w/ solid areas, cysts filled w/ "machine oil" fluid (protein and chol crystals), dystrophic calcification
Dupuytren's contracture
Slowly prog fibroprolif dz of palmar fascia, nodules form on fascia --> contractures that draw fingers into flexion
Churg-Strauss (eGPA)
Small to medium vessel vasculitis, late-onset asthma, rhinosinusitis, eosinophilia, asymmetric multifocal neuropathy from involvement of epineural vessels (mononeuritis multiplex) --> wrist drop, pANCA/MPO (neutrophil myeloperoxidase)
Telangectasias
Small, permanent dilations of superficial caps or venules, blanch under pres, seen in aging, chronic solar damage, long term steroid use, rosacea
Neuroblastomas
Small, round, blue cell tumors w/ neuritic process (neuropil), N-myc, elev urine levels of homovanillic acid
Two elastic spheres w/o surfactant, one large and one small, valve b/n them is opened
Smaller sphere collapses. Smaller sphere has larger distending pres (P = 2T/r) --> when valve opens, air flows from high pres (small sphere) to low pres (large pres)
Bicuspid aortic valve murmur
Soft SEM at R 2nd ICS
Which muscle tendons combine to form the Achilles?
Soleus and gastroc
Esophageal SCC
Solid nests of neoplastic squamous cells w/ abundant eosinophilic cytoplasm and distinct borders, keratin pearls, intercellular bridges b/n squamous cells. In pts w/ chronic etoh use and smoking. Sx: solid food dysphagia, wt loss
S/e of carbonic anhydrase inhibitors
Somnolence, parasthesias, urine alkalinization, met acidosis, dehydration, hypoK, hypoNa
Hereditary spherocytosis
Spherocytes lacking spectrin and ankyrin are less deformable than normal RBCs and are prone to sequestration and acc destruction in spleen --> hemolytic anemia, jaundice, splenomegaly. Infection can trigger acute hemolytic crisis
Spherules, sporangia, nonseptate hyphae
Spherules - Coccidioides, sporangia - Rhizopus, nonseptate - Mucor/Rhizopus
Werdnig-Hoffmann
Spinal muscular atrophy (SMA) type I - degeneration of ant horn cells of spinal cord. LMN lesion only, symmetric weakness, floppy baby, flaccid paralysis, tongue fasciculations
Shopping cart sign (neurogenic claudication)
Spinal stenosis. Common in lumbar region. Compression of nerve roots --> posture-dep LE pain, numbness, parasthesia, weakness. Most common cause is degen arthritis of spine, over age 60 --> IVD degen, loss of ht, inc load on post column, hypertrophy of ligamentum flavum
Derivatives of mesoderm
Spleen, muscle, bone, lymphatics, CV sys, kidneys/ureters
Non-cirrhotic cause of gastric varices
Splenic vein thrombosis due to chronic pancreatitis, pancreatic cancer, or abdominal tumor. Splenic v runs along post surface of panc, can clot from panc inflam
Three characteristic findings of eczema
Spongiosis, pruritic, responds to steroids
How do children respond to Tet spells?
Squatting. ToF characterized by high PVR and low SVR (due to pulm stenosis and overriding aorta providing low resistance path for deoxygenated RV blood). Squatting quickly inc SVR, ~PVR --> forces blood thru pulm circ, inc CaO2
Stages of sarcoidosis
Stage 1 - bilat hilar lymphadenopathy, Stage 2 - bilat hilar lymphadenopathy w/ pulm infiltrates in upper lobes, Stage 3 - disappearance of bilat hilar lymphadenopathy (lung infiltrates only), Stage 4 - lung fibrosis
Most common organisms that infect in CGD
Staph aureus, Burkholderia cepacia, Serratia marcescens, Nocardia, Aspergillus
Nested case-control
Start w/ cohort studies and follow participants over time, and participants who develop outcome of interest become cases for a case-control study
Myopathy is a serious risk w/ which two chol meds?
Statins and gemfibrozil (latter impairs hepatic clearance of statins)
Diff b/n steroid hormone receptor and other intracell receptors
Steroid hormone receptor is in cytoplasm and translocate to nuc after ligand binding; receptors for thyroid hormone and Vit A/D are always in nuc
Necrotic keratinocytes in the epidermis
Stevens-Johnson syndrome
Function of IL-2
Stimulates growth of helper, cytotoxic, and regulatory T cells, and NK cells. Inc activity of T cells and NK cells gives anti-tumor effects (IL-2 is aldesleukin and used as tx for metastatic melanoma and RCC)
Graves exophthalmopathy
Stimulation of orbital fibroblasts and adipocytes by TRAb and activated T cells
Edematous nasal mucosa and punctate bleeding after topical decongestant
Stop the decongestant. Vasoconstriction by alpha-adrenergic agonists (phenylephrine, oxymetazoline) undergoes tachyphylaxis --> neg feedback leads to dec prod of norepi --> vasodil, edema, congestion and exacerbation of sx.
Most common benign vascular tumor in children
Strawberry (capillary) hemangioma. GROW RAPIDLY and then regress by late childhood. Bright-red near epidermis or violaceous when deeper, compressible plaques w/ sharply demarcated borders. Cherry hemangioma are most common benign vasc prolif in adults
Causes of AOM in kids
Strep pneumo or H flu. H flu is either nontypeable (no capsule produced) or Hib (encapsulated serovars are a-f) --> vaccine only to Hib, which causes bacteremia, pneumonia, epiglottitis, meningitis
Conditions assoc w/ types of incontinence
Stress ~ obesity, vaginal delivery, prostate surgery. Urgency ~ UTI. Overflow ~ diabetes (diabetic autonomic neuropathy affects detrusor m innerv), BPH, MS
Pathophys of types of incontinence
Stress ~ urethral hypermobility/urethral sphincter weakness, urge ~ detrusor overactivity, overflow ~ detrusor underactivity/BOO
Crohn's disease complications
Strictures due to bowel wall edema, fibrosis, hypertrophy (thickening of the muscularis mucosa) --> narrowing of intestinal lumen, bowel obstruction
Class IC
Strongest binding, slowest to dissociate, good for blockade at high HR (fast HR --> cells spend more time in open/inactivated state vs resting. Good for terminating tachyarrhythmias)
Reason for lack of Neisseria immunity for long period of time
Structural genes for pili undergo antigenic variation at a high frequency; undergo recombination to produce new antigenic types
Neuro sx of Vit B12 def
Subacute combined degeneration of SC (degen of dorsal columns [loss of position and vibration, sensory ataxia - +ve Rombert], lat corticospinal tract (spastic paresis), spinocerebellar (ataxia))
Inflammatory disruption of follicles and multinuc giant cells
Subacute granulomatous thyroiditis (inc ESR/CRP, transient hyperthyroid state, dec radioiodine uptake, self-limited and resolves in <6 wks)
Diabetes med w/ sig risk of hypoglycemia despite IV dextrose
Sulfonylurea. Binds to receptor on panc beta cells to inhibit ATP-dep K chan --> inc insulin secretion INDEPENDENT OF [BLOOD GLUCOSE]. Sig risk of hypoglycemia
Laternal nasal wall contains which structures?
Sup, middle, inf turbinates --> warm, humidify, and filter inspired air. Superior - drains sphenoidal and post ethmoidal sinuses. Middle - drains frontal, maxillary, and ant ethmoidal sinuses (most common site of nasal polyps). Post - drains nasolacrimal duct
Which immune cells prevent Candida, superficial and disseminated?
Superficial - Th cells (HIV inc risk of superficial Candidiasis), disseminated - neutrophils prevent hematogenous spread (candidemia, endocarditis)
Fascial layers of neck
Superficial cervical - platysma and subQ, deep - investing, pretracheal, prevertebral, carotid sheath
Lymph drainage
Superficial inguinal - external genitalia and anus below dentate line (except glans penis and post calf), superior bladder - ext iliac, inf bladder - int iliac, prostate - int iliac, testes - para-aortic, upper 1/3rd rectum - inf mesenteric
Foramen cecum
Superior end of obliterated thyroglossal duct, midline neck mass (thyroglossal cyst)
Nerve damaged during hip surgery or buttock injections. Trendelenberg sign, gluteus medius lurch
Superior gluteal n (innerv glut med, glut minimus, TFL). +ve Trendelenberg: pelvis sags towards unaffected/contralat side when pt stands on affected leg. Gluteus medius lurch: when walking, pt leans towards affected/ipsilat side to compensate for hip drop
Consequences of CCl4 toxicity (lipid peroxidation activated by C450)
Swelling of ER, destruction of mito, inc permeability of cell membranes
Adjustment d/o
Sx occur w/in 3 mo of onset, do not persist for more than 6 mo after stressor
Whipple's triad
Sx of hypoglycemia (tremor, diaphoresis, confusion), low blood glu level, relief of hypoglycemic sx when blood glu level is inc
Severe asthma
Sx throughout day, nighttime sx daily, sx w/ limited activity, frequent exacerbations requiring oral steroids, dec lung fcn on PFTs, frequent use of short-acting beta-agonists
Pathology of celiac dz (presents at age 6-24 mo, gluten new in diet)
Sx: abd pain, N/V, flatulence, diarrhea, wt loss, short stature, IDA, dermatitis herpetiformis. Gliadin causes immune-med rxn --> villous atrophy, crypt hyperplasia, intraepith lymphocyte infiltration. Duodenum and jejunum exposed to highest [gliadin]. W/u is duodenal biopsy
Troponin T, I, C
T - binds other troponin components to tropomyosin, I - binds troponin-tropomyosin complex to actin, C - binding site for Ca
Which ALL is more likely to p/w mediastinal mass?
T cell ALL
Pt w/ MDD overdoses, wide QRS interval and vent arrhythmias
TCA overdose. Tx: Sodium bicarb. Other sx incl delirium, coma, dry mouth, blurred vision
Linear development of aorticopulmonary septum in utero
TOGA (spiral development is normal)
Rb1 mutation
TSG, chrom 13, inc risk of retinoblastoma and osteosarcoma
What lab test must you check before starting etanercept?
TST. TNF-alpha is necessary for effective sequestration of TB and etanercept can promote reactivation of latent TB
Thiazolidinediones MOA
TZDs bind to PPAR-g, forming heterodimer w/ RXR --> 1) upreg GLUT-4, and 2) inc adiponectin (inc # of insulin-responsive adipocytes, and enhances insulin sensitivity and FA oxidation)
Signs of tension pneumothorax
Tachycardia, hypotension, hypoxemia, absence of breath sounds, hyperresonance to percussion on affected side. Tx: emergent thoracostomy
Hairy cell leukemia
Tartrate resistant acid phosphatase (TRAP)
Most common site of anal fissure
Tear below pectinate line, pain while pooping, located posteriorly b/c this area is poorly perfused
Topoisomerase II (DNA gyrase)
Temporarily cleaves both strands of DNA helix in prokaryotes and introduces negative supercoiling into circular DNA
Which structure is used as a landmark during appendectomy?
Teniae coli (continuous layer of longitudinal muscle that forms 3 distinct bands, eventually converging at root of appendix)
Mediastinum shift in tension pneumothorax vs spont
Tension - pushed away, spont - towards
S/e of isotretinoin
Teratogenic (spont abortion, fetal malformation), hyperlipidemia, cheilitis, dry skin, myalgias, pseudotumor cerebri
Loss of cremasteric reflex
Testicular torsion or L1-2 spinal injury (mediated by genitofemoral n)
Male genitalia lymphatic drainage
Testis ~ para-aortic, prostate ~ int iliac, glans penis ~ deep inguinal, scrotum ~ superficial inguinal
Tetanus vs botulism toxin
Tetanus - retrograde axonal transport, prevent release of inhibitory NTs GABA and glycine. Botulism - inhibits ACh release, causing flaccid paralysis
Window period of Hep B
Time b/n disappearance of HbsAg and appearance of anti-HbsAg. Only IgM anti-HbC is present in serum in the window period
Incubation vs latent period
Time from initial exposure to clinical manifestation of disease (incubation - infectious, latent - noninfectious)
Microsporum
Tinea capitis and tinea corporis
Reactive arthritis
Triad of urethritis, conjunctivitis, arthritis, sterile jt effusion. Asymmetric arthritis of large jts. Keratoderma blennorrhagicum (hyperkeratotic vesicles on palms and soles) and circinate balanitis (serpiginous annular dermatitis of glans penis). Immune complex to Ags
Treatments of open angle glaucoma
Trabecular outflow (muscarinic agonists - miosis, make anterior chamber angle wider --> inc outflow); uveoscleral outflow (PG agonists); aqueous humor inflow (BB, a2-AR agonists, acetazolamide)
Radial n injury
Tracks w/in radial groove of humerus, vulnerable to trumatic injury at humeral midshaft. Radial n innerv all extensors of UE, injury causes wrist drop
Pyroxidone is needed for which processes?
Transamination (b/n AA and alpha-keto acid) and decarboxylation of AAs, for GNG. TRANSAMINATION: glutamate (AA) + OA (alpha-ketoacid) --> aspartate (AA) + a-KG
DNA binding proteins
Transcription factors (Myc, CREB), steroid receptors (cortisol, aldo, prog), thyroid hormone receptor, fat-soluble vitamin receptors (Vit D, retinoic acid), DNA transcription and replication prots
RNA interference
Transcription of miRNA --> processing into short RNA helix by dicer --> RISC --> mRNA degradation
Pathogenesis of Huntington's disease
Transcriptional repression (silencing) by increased histone deacetylation --> silencing genes needed for neuronal survival. Gain of function mutation
Why do pts w/ selective IgA def get anaphylaxis w/ transfusion?
Transfusions contain small amts of IgA, and pts have IgE antibodies against IgA (anti-IgA Abs)
Chikungunya
Transmitted by Aedes mosquito like dengue. Febrile illness w/ flulike sx, prominent polyarthralgias/arthritis (hands, wrists, ankles), diffuse macular rash
Bleeding into pelvic cavity
Trauma (pelvic fracture) or GYN hemorrhage (ruptured ectopic preg)
Why is stress incontinence more common in women?
Trauma to external urethral sphincter or pudendal nerve common during vaginal childbirth
Desmopressin
Treatment of central DI and nocturnal enuresis, inc circ levels of vWF and promotes coagulant activity of FVIII
PNH
Triad of hemolytic anemia (hemoglobinuria), pancytopenia, thrombosis at atypical sites
Congenital toxoplasmosis
Triad of intracranial calcifications, hydrocephalus, chorioretinitis
Hemolytic uremic syndrome
Triad of microangiopathic hemolytic anemia, thrombocytopenia, renal insufficiency. After E coli O157:H7 infection
Wernicke encephalopathy, and acute confusion after IV glucose
Triad of ophthalmoplegia (horizontal nystagmus, bilat abducens palsy), ataxia, confusion. Thiamine needed for glucose metabolism --> IV glu alone further depletes existing thiamine def --> precipitate encephalopathy. ALWAYS GIVE GLUCOSE AND THIAMINE
WPW
Triad of short PR interval, widening of QRS, delta wave (slurred and broad upstroke of QRS). Preexcitation of ventricles thru extra conduction pathway (bundle of Kent)
Triad of vestibular Schwammona
Triad of tinnitus, vertigo, and hearing loss. Occurs at cerebellopontine angle. Bilateral = NF2, can be unilateral.
Carvallo sign
Tricuspid regurg murmur is expected to increase in intensity during inspiration, whereas MR and VSD murmurs do not change
Atopic eczematous dermatitis
Triggered by env factors, present by age 5, red, weeping/crusted lesions, lichenification in flexural distribution. Mutations in filaggrin --> impairment of skin's barrier fcn. Severity lessens w/ age, intense pruritis, high serum IgE, peripheral eosinophilia, high cAMP phosphodiesterase in leukocytes
Posterior neck mass, lymphedema (nonpitting)
Turner (XO): short stature, streak ovary, shield chest, coarct of aorta, horseshoe kidney, lymphatic defects
Malrotation of intestine leads to what complication?
Twisting of intestinal loop (volvulus), due to abnormal positioning of intestine in abdominal cavity
Why is a washout interval needed for MAOIs?
Two weeks to synthesize MAO. If SSRI is given before 2 weeks, high risk of serotonin syndrome
Types of 5alpha-reductase
Type 1 - postpubescent skin, type 2 - genitals (deficiency of 5-AR2 causes male pseudohermaphroditism)
Type A vs B aortic dissection
Type A - dissection involving any portion of ascending aorta, Type B - confined to descending aorta --> dissection causes compromise of brachiocephalic trunk, brachial BP discrepancy
Which hypersensitivity are neutrophils important in?
Type III - deposited immune complexes activate complement and stimulate PMN-med tissue damage
Salmonella enteritica
Typhoid fever, fever, abd pain, diarrhea, constipation (rarely hepatosplenomegaly, intestinal perforation)
Primary CNS lymphoma
Universally associated with EBV. Most frequent tumor in immunosuppressed pts. Dense, cellular aggregates of uniform, atypical lymphoid cells.
Presentation of unilat injury to CN V3
Unopposed action of contralat pterygoid mm --> deviation of mandible toward paralyzed side
Structures that drain into infraclavicular LNs
Upper limb and breast
Rubrospinal tract
Upper limb flexors. Damage above red nuc - decorticate, damage at or below - decerebrate
Positional effects on deposition of object in lung lobes
Upright position - RLL, supine - post segment of RUL or sup segment of RLL
Parinaud syndrome
Upward gaze palsy, absent pupillary light reflex, impaired convergence
Urea handling in tubular sys
Urea is filtered at glom, passively reabsorbed in prox tubule and med CD, passively secreted by thin regions of LoH
Structure most sensitive to injury in hysterectomy
Ureter - damaged during ligation of uterine vessels. Pt can urinate normally if ureter damage is unilat
Orototic aciduria (cf OTC def)
Uridine monophosphate synthetase def --> orotic acid accum, but no hyperammonemia. Sx: megaloblastic anemia delayed growth
Causes of hypoMg
Urinary losses due to meds (loop diuretics), etoh use, uncontrolled DM w/ polyuria
Cladribine
Used in hairy cell leukemia, cytotoxic purine analog resistant to degradation by ADA
100% oxygen
Used to abort cluster headaches
RV/TLC ratio
Used to distinguish diff types of pulm dz. Elev RV/TLC ~ obstructive (air trapping in lungs, RV inc is what drives the TLC inc), normal RV/TLC ~ restrictive (flows normal)
Blood supply to uterus
Uterine aa (branch of internal iliac), ovarian a (branch of abdominal aorta). Blood flow thru ovarian a compromised in ovarian torsion
Loss of what ligamentous support causes uterine prolapse into vagina?
Uterosacral ligaments hold the uterus in anteverted or retroverted position, whereas round ligament maintains anteflexion of uterus
Alveolar hyperventilation (if uncorrected, persistent tachypnea leads to eventual resp muscle fatigue, hypoventilation, hypercapnia)
V/Q mismatch causes dec O2 and CO2 exchange (pneumonia or PE) --> hypoxemia stim peripheral chemoreceptors, inc resp drive --> excessive CO2 excretion, hypocapnia; however, V/Q mismatch remains (poorly ventilated regions remain). Tx: 100% O2
ADH activities (V1 and V2)
V1 - vasoconstriction and inc PG release, V2 - antidiuretic response. ADH also inc # of passive urea transporters in medullary CD --> urea resorption contributes to hyperosmolarity of medulla
Polycythemia vera
V617F involving JAK2 gene, ABNORMAL TRANSDUCTION OF EPO SIGNALING. More sensitive to GFs like EPO and thrombopoietin, elev WBCs, pruritis during hot showers (histamine release from basophils), gout, ruddy face, splenomegaly. Assoc w/ PUD (altered mucosal blood flow due to inc viscosity) and gouty arthritis (inc RBC turnover)
SEQUELA OF SAH
VASOSPASM LEADING TO CLINICAL SX. TX: CCB (Nimodipine is cerebral selective drug). Substances created by the deg of subarachnoid blood clots are the etiologic agents
Fcn of VPL and VPM
VPL - input from STT and DCML, VPM - trigeminal pathway
Herpes zoster ophthalmicus
VZV reactivation at the level of the trigeminal ganglion of cranial nerve V1
Inferior vermis and flocculonodular lobe (vestibulocerebellum)
Vertigo and nystagmus
Acute aspirin overdose
Vertigo, tinnitus, vomiting, diarrhea. Severe intoxication: coma, hyperpyrexia, pulm edema, death
Visceral vs somatic pain of appendicitis
Visceral - luminal distension and stretching of smooth muscle, midline, poorly localized. Somatic - irritation of parietal peritoneum
Subacute combined degeneration
Vit B12 def --> degen of dorsal columns and lat cerebrospinal tracts --> distal prog weakness and ataxia, spasticity, parasthesia, macrocytic anemia
Near collisions driving at night, coarse and dry skin, pruritis
Vitamin A deficiency DUE TO PRIMARY BILIARY CHOLANGITIS (malabsorption of ADEK, pruritis from bile acid accum in skin). Other causes of Vit A def are insuff dietary intake, panc insuff, IBD/intestinal malabsorption
Most imp labs to check in metabolic alkalosis
Volume status and urine chloride (low urine Cl- and hypotension suggests vomiting (responsive to isotonic saline and volume repletion), high urine Cl- and hypotension suggests acute thiazide/loop diuretic abuse (saline responsive, low urine Cl- after stopped), high urine Cl- and hypertension suggests mineralocorticoid excess state (saline-unresponsive)
Aldolase B def (fructose 1-phosphate aldolase def)
Vomiting and hypoglycemia in infants after fruit juice ingestion. Fructose-1-phosphate accum --> depletes IC PO4, inhibits GNG
Progesterone w/d test on endometrium
W/d prog --> inc PG prod, vasoconstriction of spiral aa --> apoptosis of endometrial epith, degeneration of stratum functionalis, sloughs off as endometrial flow
Wiskott-Aldrich
WATER: Wiskott-Aldrich, thrombocytopenia, eczema, recurrent pyogenic infections from H flu, Strep pneumo, Neisseria. Combined B and T lymphocyte d/o
Lateral traction on infant's neck during delivery
Waiter's tip/Erb palsy - palsy characterized by shoulder adduction, elbow extension, and forearm pronation
Warfarin vs heparin overdose
Warfarin: Vit K is effective (takes days), FFP is effective, protamine is ineffective. Heparin: Vit K ineffective, FFP ineffective (contains ATIII, enhances heparin effect), protamine effective
SLE
Warm autoimmune hemolytic anemia (spherocytosis, +ve direct Coombs, extravasc hemolysis), SLE-assoc thrombocytopenia from Abs against platelets, symmetric, migratory arthritis
Which areas are most threatened by ischemic colitis?
Watershed areas (splenic flexure - border of SMA and IMA; rectosigmoid jcn - border of sigmoid a and sup rectal a). During severe hypotension in pts w/ underlying art insuff (DM, PVD)
VIPoma
Watery diarrhea, WDHA syndrome (watery diarrhea, hypoK, achlorhydria), aka pancreatic cholera. Tx: exogenous somatostatin
Gastrulation
Week 3 of embryogenesis, initiated by formation of primitive streak (thickening of epiblast layer that appears at caudal end of embryo and grows cranially)
Meningiomas
Well-circumscribed, round masses attached to dura and at falcine, parasagittal, or lateral convexities of brain. Sz occur due to compression of adj cortex. HA, N/V from inc ICP, worsens w/ recumbency and during sleep
Intertrigo
Well-defined erythematous plaques w/ satellite vesicles or pustules in warm moist skin areas (axillae, groin, skin folds), due to Candida, common in immunocompromised or post abx
Multi-compartment drug distribution model
Well-vascularized peripheral compartment (initial rapid distribution, more lipophilic tissues) ~ brain, kidney, liver, lungs, heart. Poorly-vascularized peripheral compartment (delayed distribution) ~ skel muscle, bone, fat
Magenta on PAS and diastase resistant
Whipple disease. Tropheryma whippelii replicates w/in Mos (Foamy Whipped Cream in a CAN) --> hence, no systemic inflam response is seen
Distended Mos in the intestinal LP
Whipple dz (malabsorptive diarrhea, wt loss, jt pain)
Pseudomembranes
White-yellow plaques composed of fibrin, inflam cells and cellular debris
Presentation of right to left shunting in large septal defects and ToF
Whole-body cyanosis
Fracture of midshaft of humerus
Wrist drop
Mechanism of therapeutic XRT, UV rad, and alkylating agents
XRT - DNA double strand breakage and free radical formation. Cell survival initially plateaus and later rapidly increases in cell death. UV - lower energy, not enough to break strands, causes thymine dimers. Alkylating agents - DNA cross-linking
Is chancroid painful?
YES! "You do cry" with H ducreyi
gp41 and gp120
gp120 - viral attachment by binding CD4 receptor, gp41 - mediates fusion b/n virus and target cells by anchoring gp120 via noncovalent interactions
vWD
vWF is deficient, causing impaired platelet adhesion; FVIII deficiency causes PTT elev