Bugs and Drugs

HIV ppx

- CD4 < 200: TMP/SMX (PCP) - CD4 < 100: TMP/SMX (Toxo) - CD4 < 50: Azithromycin (MAC)

Organisms that cause UTI

#1: E. Coli. Also: proteus, klebsiella, enterobacter, citrobacter, pseudomonas (and staph sapro in sex active women)

Trich vs BV

(KOH for the whiff test)

Borrelia recurrentis

-Relapsing fever -Louse (recurrent due to variable surface antigens)

Abx that affect ribosome

50S: chloramphenicol, clindamycin, linezolid, macrolides (azithro,clarithro, erythro), streptogramins (-pristin). 30S: aminoglycosides (-mycin) and tetracycline and tigecycline

what kind of drug would decrease the vmax of of norephinephrine?

A noncompetitive antagonist or irreversible antagonist of a1 receptors. Phenoxybenzamine is an irreversible a1 and a2 antagonist. Primarily used in pheochromocytoma. (Phentolamine is a reversible, competitive agonist)

HIV drug need to test for HLA-B*57:01

Abacavir: causes fever, malaise, GI sx, rash. A type 4 hypersensitivity.

Botulism infection

Adults: ingest preformed toxin In babies: ingest spores --> floppy baby 4 Ds: diplopia, dysarthria, dysphagia, dyspnea.

Schistosomiasis bladder

Calcifications of the bladder wall are essentially pathognomonic. Also increased risk of squamous cell carcinoma of bladder...not your typical urothelial carcinoma.

Pseudohyphae with blastoconidia

Candida

What drugs cause SIADH

Carbamazepine, SSRIs and TCAs, cyclophosphamide, and others...

Organophosphate pesticides

Cause cholinergic toxicity in people. Can be used as chemical weapon. Inhibit acetylcholinesterase so increase cholinergic tone + nicotinic hyperactivity --> muscle weakness. Manage with atropine (Competitive inhibitor of Ach at muscarinic so will treat DUMBELS) and Pralidoxime - a cholinesterase-reactivating agent that works at nicotinic (weakness) and muscarinic sites... GIVE ATROPINE FIRST! If give pralidoxime first, it can cause transient AChE inhibition --> worsen symptoms.

reversal of nondepolarizing NMJ blockade (-roc-)

Cholinesterase inhibitors, such as neostigmine (given with atropine), edrophonium, etc.

Penicillamine for Wilson

Copper chelating agent that solubilizes copper --> excreted in urine. With initial treatment, urinary excretion of copper is high. As copper stores diminish, the excretion decreases. Nephrotoxicity is an ADE of the drug. Usually presents as nephrotic syndrome (proteinuria) due to membranous nephropathy. Thickening of glomerular basement membrane with mesangial or subendothelial deposits.

DOAC vs Warfarin

DOAC: >1 dose daily may be required. No dietary restrictions. Few drug interactions. No monitoring required. Renal failure may prohibit use. Less variability in therapeutic effect. Warfarin: Once daily. Stable vitamin K intake required. Many drug interactions. Require INR monitoring. No prohibitions with comorbid conditions.

Medroxyprogesterone use

Decreases endometrial hyperplasia and endometrial carcinoma in pts on estrogen. Inhibits pituitary secretion of FSH and LH. So GnRH would be increased.

Bosentan, Ambrisentan

Decreases endothelin by inhibiting the endothelin 1 receptor (drug used in scleroderma associated PAH or just pulmonary arterial hypertension)

Where does mannitol act in kidney

Decreases sodium and water reabsorption by Proximal tubule and descending loop of henle

Polio

Destruction of LMN in anterior horn --> flaccid paralysis, atrophy, fasciculations

What are hypotonic IV fluids and when would you use?

Dextrose 5% in water, .45% (half normal) saline - these are used for free water deficit (hypernatremia). Dextrose 5% in .45 saline is initially hypertonic but becomes markedly hypotonic due to glucose metabolism - use this for maintenance hydration.

Factor Xa inhibitors

Direct: Rivaroxaban, Apixaban. Indirect: Fondaparinux. This inhibit *Xa* - not conversion of X to Xa. So this directly prevents conversion of II to IIa (thrombin)!!! Used for stroke prevention in a-fib.

Second gen antipsychotics MOA

Dopamine D2 antagonism and serotonin 2a antagonist (1st gen only have the d2 effects)

Cabergoline

Dopamine agonist (prolactinoma)

DRESS

Drug Reaction with Eosinophilia and Systemic Symptoms. Drugs trigger robust CD4+ and CD8+ response against hepatic proteins. Fever, lymphadenopathy, and skin manifestations. Liver injury may occur too.

MCC acute bacterial prostatitis

E coli. Other common causes: proteus, klebsiella, pseudomonas.

HIV window period

Early infection when serologic and antigen testing for HIV are not yet positive.

beta blocker that is most rapid acting and exhibits short half life

Esmolol

Kid was totally fine. Then abrupt onset high fever. Strained breathing. Low bp. She is setting up and leaning forward. What's going on and what else may be seen?

Febrile, ill appearing patient in respiratory distress who is in the tripod position: *epiglottitis* by h flu. Causes laryngeal obstruction --> inspiratory stridor. Tripod positioning opens the airway.

Chlorpheniramine

First gen anti histamine

Drugs that cause QT prolongation

Fluoroquinolones, Macrolides (ex. erythromycin) Antiemetics (ex. ondansetron) Azoles (ex. fluconazole) Antipsychotics, TCAs, methadone Class 1A antiarrhythmics (ex.quinidine) Class 3 antiarrhythmics (ex. dofetilide, sotalol) Electrolyte imbalances: hypokalemia, hypomagnesemia.

Nucleotide analog that doesn't require intracellular activation

Foscarnet

Lithium toxicity

GI, neuro (ataxia, tremor, delirium). Anything that decreases GFR can increase its retention. Thiazides stimulate its retention by blocking sodium reabsorption in distal tubule, so that stimulates increased proximal sodium/lithium absorption --> toxicity. ACEI and NSAIDs can also impair clearance.

DNase

Group A strep. Degrades DNA in pus to allow spread.

Congenital rubella

Hearing loss, cataracts, PDA, blueberry muffin rash. Microcephaly, neurodevelopmental delay, extramedullary hematopoiesis. May cause chorioretinits. Mom would have low grade fever, maculopapular rash that starts on face and spreads down, and LAD. And then develop polyarthritis, polyarthralgia.

Management of uterine atony (like after a birth)

IV fluids, uterine massage, Oxytocin. Oxytocin binds Gq --> increased intracellular calcium

Dabigatran reversal

Idarucizumab - a monoclonal antibody that binds and inhibits it.

Cyclosporine - use, ADE

Immunosuppressant used in patients that have undergone solid organ transplant. Impairs renal excretion of uric acid --> gout. Calcineurin inhibitor. Prevents IL-2 transcription. Highly nephrotoxic. Also gingival hyperplasia and hirsutism. Tacrolimus (also a calcineurin inhibitor) is also nephrotoxic. Sirolimus isn't.

Thiazides and calcium

Increase calcium reabsorption in distal tubule

Using abx for salmonella

Increases shedding time

Cryptosporidium

Ingest oocyst in contaminated food/water. Sporozoites attach to epithelial cells. Healthy people: watery diarrhea. AIDS: light threatening diarrhea. Dx: acid-fast stain of stool reveals oocysts. Histology: villous blunting, inflammation of lamina propria, and basophilic crypto organisms on brush border mucosa.

Reserpine

Inhibits VMAT. Blocks dopamine entry into presynpatic vesicles.

CMV receptor, rhinovirus receptor

Integrins (heparan sulfate) rhinovirus-icam-1

What inhibits Topo 1?

Irinotecan and topotecan

Alcohol based disinfectants vs bacteria

Kill ENVELOPED viruses by dissolving the membrane. Alcohol kills vegetative bacteria not spores), fungi too.

What viral drugs need to be activated?

Lamivudine (HIV) and Ganciclovir (CMV) and Acyclovir (viral thymidine kinase then cell kinase)

Gram positive rods

Listeria, Clostridium, Bacillus, Corynebacterium, mycobacterium and Nocardia and actinomyces

Strep pneumo lung sounds

Lobar pneumonia. Focal rales, not diffuse

Isotretinoin teratogenic effects

Microcephaly, thymic hypoplasia, small ears, hydrocephalus

Salivary gland swelling

Mumps

Causes of common cold and symptoms

Nasal congestion, discharge, sneezing, cough and sore throat. Rhinovirus, influenza virus, coronavirus

Structure of rhinovirus. And disease it causes

Non-enveloped positive sense RNA

Treatment of C diff

Oral vanc or fidaxomicin. Or metronidazole.

Misoprostol

PGE1 agonist that can induct uterine contractions

Head lice = and treatment

Pediculus humanus capitis. Permethrin, ivermectin.

Scabies biopsy and treatment

Permethrin: blocks voltage gated sodium channel.s Oral ivermectin is alternative

Phenoxybenzamine use

Pheochromocytoma. alpha blocker.

Vaccines that are inactivated/killed

Polio, Hep A, Influenza

Naegleria fowleri

Primary amebic meningoencephalitis. Flagellated protozoa. Penetrates olfactory mucosa and migrates in retrograde fashion thru olfactory nerve to brain.

MESNA

Protects the kidney from acrolein metabolites from cyclophosphamide chemo treatment. Supplies a thiol that inactivates acrolein. Prevents hemorrhagic cystitis (hematuria and suprapubic tenderness)

Tinea pedis

Pruritic erythematous rash of feet. Microscopy: branching hyphae. Dermatophytes: trichophyton rubrum. Treat with topical antifungals, including -azoles (miconazole, clotrimazole), terbinafine, and tolnaftate.

Patients taking isoniazid should supplement with

Pyridoxine to prevent drug induced peripheral neuropathy

Hiking in the rocky mountains and get fever, vomiting, myalgia, weakness

Reovirus --> coltivirus --> colorado tick fever

What are some features of rabies

Restlessness, agitation, dysphagia. Can be paralytic and have spasticity.

Live attenuated vaccines

Rotavirus, measles, mumps, rubella, varicella

Common pathogens in patients with sickle cell

S pneumo, N meningitidis, H flu. (capsule) Vaccinate! And urgent abx if a patient presents with signs of infection

Treatment of panic disorder

SSRI and SNRI

HHV-6/7 transmission

Saliva.

Use of permethrin

Scabies

Treat trematodes

Schistosoma: praziquantel Clonorchis sinensis (pigment stones and cholangiocarcinoma): praziquantel

Trypanosoma cruzi

Slender C- or U- shaped flagellated parasite with dark nucleus and kinetoplast. Can cause absence of distal esophageal peristalsis and incomplete relaxation of lower esophageal sphincter (due to inflammation and immune mediated cross-reactivity). ----> megaesophagus. Also get cardiomyopathy and megacolon. High risk of esophageal cancer.

Octreotide

Somatostatin analogue used for refractory chemo-induced diarrhea...and other things.... Reduces secretion of pancreatic and GI hormones.

What drugs cause neuromuscular blockade?

Succinylcholine, rocuronium. Use this to help with intubation.

Neurocysticercosis

Taenia solium: pork tapeworm. Common in central/south america. Cystic brain lesion. Patients develop seizures. Cysts --> tapeworm infection. Eggs (from stool of tapeworm carriers) --> neurocysticercosis

Treatment of tapeworms

Taenia solium: praziquantel (+bendazole for neurocyst) Diphyllobothrium latum: praziquantel Echinococcus granulosus: albendazole

Lecithinase

Toxin A by clostridium perfringens. Hydrolyzes lecithin in cell membranes. Cell lysis --> gas gangrene.

Diarrhea with inflammation and necrosis of peyer patches

Typhoid stains of salmonella.

ADE for foscarnet

Used for CMV. Nephrotoxicity and electrolyte disturbances.

What stimulates angiogenesis?

VEGF and FGF-2

treat nephrogenic diabetes insipidus

Water supplementation and actually administering thiazides (increases sodium/water reabsorption in proximal tubule so less water is delivered to collecting duct)

What drugs inhibit CYP

acute use of alcohol, isoniazid, cimetidine, macrolides, quinolones, azole antifungals, amiodarone, protease inhibitors (ritonavir), SSRIs, diltiazem/verapamil, and grapefruit juice

NE receptor binding and effects on SVR and renal blood flow

a1 = b1 > b2. Increase SCR and decreases renal blood flow

Terbutaline

beta 2 agonist

Colesevelam

bile acid sequestrant: decrease reabsorption of bile acids from intestine --> make more cholesterol into bile acids

Where do K+ sparing diuretics act?

cortical collecting duct (ex. sodium channel blockers - amiloride, aldosterone antagonists)

Lipoteichoic acid

major component of cell wall of most gram+ bacteria. Regulator of autolytic cell wall enzymes

Argatroban

direct thrombin inhibitor. Use for heparin-induced thrombocytopenia.

Peritrichous flagella

flagella all over: proteus mirabilis

what's protective against malaria

g6pd sickle cell trait thalassemia

intestinal nematode most associated with resp sx

giant roundworm: ascaris lumbricoides

pseudomonas stain/shape/features

gram negative rod, oxidase positive, produces green pigment. Mucopolysacc capsule phospholipase C: degrade cell membranes Endotoxin: fever/shock Exotoxin A: inactivates EF2 Generates ROS

Rabies vaccine

inactivated virus

daptomycin

lipopeptide that disrupts cell membrane of gram+ by creating transmembrane channels. used for staph skin infections

Denosumab

monoclonal antibody that binds RANK-L and prevents its interaction with RANK (less osteoclast activation)

How can non-virulent strep pneumoniae acquire virulence?

transformation: take up exogenous DNA. Then strains that didn't have capsule can get a capsule and cause disease. (also, h flu, strep, bacillus, neisseria)

treat leprosy

tuberculoid (mild) form: dapsone and rifampin lepromatous: add clofazimine

Who has IgA protease and why is it useful?

IgA is on mucosa and inhibits action of pili and other antigens. So the protease Facilitates bacterial adherence to mucosa. Neisseria gonorrhoeae and meningitidis, strep pneumo, h flu

Use of mupirocin

Impetigo

Use of topical mupirocin

Impetigo by staph or strep

Inhaled glucocorticoids for asthmatics

Improves symptoms, reduces need for short-acting bronchodilators, lowers risk of serious exacerbations and hospitalizations. Potentiate the bronchodilatory effect of beta 2 agonists -- upregulate the receptors (also does this with alpha1 in periphery)

Are NSAIDs bad for the kidney in a healthy person? What about a person with intravascular volume depletion (cirrhosis, heart failure, dehydration)....? How is this complicated if that pt is on a loop diuretic (684).

In a normal person, PG synthesis is low and NSAIDs have minimal effect. In intravascular volume depleted patients, they are dependent on vasodilatory effects of PGs to maintain adequate RPF and GFR. So NSAIDs in these people decrease GFR and RPF. Less fluid/electrolyte delivery --> less efficacy of loop diuretics --> reduced urinary sodium excretion and fluid retention. AVOID NSAIDS WITH RENAL DISEASE/REDUCED EFFECTIVE ARTERIAL VOLUME.

Effects of inhalation anesthetics

Increase inhibitory action of GABA. Also affect K+ channels in membrane --> hyperpolarize them. CV: myocardial depression and hypotension. Decrease CO. Respiratory: all but N2O are depressants. Also suppress mucociliary clearance (may cause post-op atelectasis). Halothane and sevoflurane are bronchodilators and are preferred in asthma pts. Brain: Fluorinated anesthetics decrease vascular resistance and increase cerebral blood flow (--> increased intracranial pressure; undesirable). Kidneys: decreased GFR, increase vascular resistance, decrease plasma flow Liver: decrease hepatic blood flow.

Treatment of glaucoma

Increase trabecular outflow: muscarinic agonists. Increase uveoscleral outflow: prostaglandin agonists (FIRST LINE). These also increase iris/eyelash pigmentation. Decrease aqueous humor production: beta blockers (timolol), alpha 2 agonists (brimonidine), carbonic anhydrase inhibitors

Stimulant (cocaine) withdrawl

Increased appetite, hypersomnia, intense psychomotor retardation, severe depression ("crash")

Anticholinergic toxicity

Increased body temp (less sweating) Decreased secretions Flushed skin (superficial vasodilation from increased body heat) Cycloplegia, mydriasis, nonreactive (paralysis of ciliary muscle and iris sphincter) Altered mental status Constipation, urinary retention Tachycardia 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. Associated with antihistamines, sleep aids, cold preparations, TCAs.

Testosterone replacement therapy

Increased prostate volume --> rise in PSA; risk of prostate cancer. Erythrocytosis, possibly due to suppression of hepcidin and increased intestinal iron absorption --> increased risk of thromboembolism. Don't initiate if baseline hematocrit is >50%. Hematocrit should be checked regularly.

PPI ADE

Increased stomach pH --> malabsorption of *calcium, iron, magnesium, B12* (chronic PPI protects exogenously administered lipase and enhances fat absorption in pts dependent on pancreatic enzyme replacement) Increased risk of infection: c diff, PNA Osteoporosis, chronic kidney disease, small intestinal bacterial overgrowth

Adenosine

Increases K+ efflux from AV nodal cells. Hyperpolarization of AV node. Also coronary arteriolar vasodilator. Useful for paroxysmal supraventricular tachycardia. Rapid onset and short half life. Most frequent ADE: flushing, chest burning, hypotension, AV block.

Use of EPO for anemia due to CKD

Increases stimulus for erythropoiesis, increases hemoglobin, improves O2 delivery. But: 1. Increases blood viscosity and triggers release of inflammatory cytokines from endothelium --> risk of thromboembolism. And promotes release of vWF and plasminogen activator inhibitor-1. 2. Increases systemic vascular resistance --> hypertensive encephalopathy and increased risk of CV events. You want to stop EPO once you reach 12-13 g/dL

Bleomycin MOA and ADE

Induces free radicals --> DNA strand breaks. Pulmonary fibrosis.

Chlamydia trachomatis life cycle

Infectious, small elementary body enters cells. Forms reticulate body that replicates. Then reorganize into elementary body. Treatment: AZITHROMYCIN or doxy. (give ceftriaxone for gonorrhea)

Entamoeba Histolytica - what it causes - dx - rx

Infects GI tract when cysts are ingested. Some patients develop colitis with ulcers and with subacute blood-mucoid diarrhea. Diagnosis: cysts and *trophozoites* in stool studies or flask-shaped ulcers with trophozoites. Can occasionally cause liver abscess in right lobe of liver. Treat: metronidazole + paromomycin

Nematode route of infection

Ingested: enterobius, ascaris, toxocara, trichinella, trichuris Cutaneous: strongyloides, ancylostoma, necator Bites, loa loa, onchocerca volvulus, wuchereria bancrofti

What causes malignant hyperthermia?

Inhaled anesthetics (except N2O), succinylcholine. qThis is an inherited condition= *RYR1 mutation* which releases too much Ca2+ when given anesthetics

How does Niacin affect cholesterol. ADE?

Inhibit lipolysis (hormone sensitive lipase). Decrease VLDL synthesis and decreased HDL clearance --> low LDL and high HDL. Gout, hepatotoxicity, pruritus.

Tricyclic antidepressants MOA ADE Overdose effects and how to treat

Inhibit reuptake of NE and serotonin. Inhibit fast sodium channel conduction --> arrhythmias. Refractory hypotension results from decreased cardiac contractility and direct peripheral vasodilation (from a1 antagonism). This is main mechanism of OD death. Treat OD with sodium bicarb (promotes TCA dissociation). Other ADE: H1 antagonism (increased sedation and appetite), anti-cholinergic, a1 antagonism (orthostatic hypotension), *inhibit cardiac fast sodium channels (arrhythmia and hypotension)*, inhibit NE and serotonin reuptake (tremor and insomnia)

digoxin MOA

Inhibition of Na/K/ATPase pumps in the heart, increasing contractility...because it indirectly inhibits the Na/Ca exchanger so there's more calcium in the cell. Also increases parasympathetic tone.

Acetazolamide

Inhibits carbonic anhydrase in proximal tubules so it blocks HCO3- reabsorption in kidneys! Also used for acute angle-closure glaucoma. Weak diuretic because most of the Na+ that's blocked from reabsorption in proximal tubule is reabsorbed more distally. Distal reabsorption: increased K+ excretion --> increased urine potassium.

Paclitaxel MOA and ADE

Inhibits microtubule disassembly. Neuropathy

Pyrimethamine

Inhibits parasite DHFR. Use in malaria.

Probenecid

Inhibits reabsorption of uric acid in proximal convoluted tubule (also inhibits secretion of penicillin). Can precipitate uric acid calculi.

Hydroxyurea

Inhibits ribonucleotide reductase --> decrease nucleotides available for DNA synthesis --> pancytopenia

Acetaminophen overdose

Initially had n/v. Now has scleral icterus, RUQ pain, elevated aminotransferases. Acetaminophen produces toxic metabolite NAPQI which is conjugated with glutathione in liver and excreted. At supratherapeutic doses, glutathione becomes saturated --> excessive NAPQI forms adducts with hepatic proteins that disrupt hepatocyte mitochondrial function and cause oxidative injury. Centrilobular hepatic necrosis. Give NAC to replete glutathione stores.

"proglottids"

Intestinal tapeworms: taenia solium, diphyllobothrium latum

When is cell mediated immune response needed? What pneumonia would cause this?

Intracellular infection. Legionella pneumophila

Treatment of vaginal candida

Intravaginal: miconazole, clotrimazole. Oral fluconazole. -conazole: prevent formation of ergosterol by inhibits cytochrome p450 dependent demethylation that does lanosterol--> ergosterol

Fever, chest pain, hemoptysis, chest imaging showing nodule with hypoattenuation consistent with "halo sign" in pt undergoing chemo...

Invasive aspergillosis

Hydroxychloroquine ADE

Irreversible retinopathy: have regular ophthalmologic exams.

Cannabis withdrawl

Irritable, anxiety, depressed, insomnia, decreased appetite

Diagnose disseminated gonococcal infection

Isolate organism on Thayer martin: chocolate agar infused with abx. It's a chocolate sheep blood agar with vanc to inhibit gram+, colistin and TMP to inhibit gram-, and nyastatin to inhibit yeast. !! pay attn - in a question they may just mention agar with a ton of abx. Pt may have polyarthralgia, tenosynovitis, dermatitis or purulent arthritis.

MOAs of components of TB therapy

Isoniazid: decreases synthesis of mycolic acid. Need bacterial catalase-peroxidase to convert to active metabolite. Give with B6. Pyrazinamide: Unknown but it's a prodrug. Ethambutol: decrease carb polymerization of cell wall by blocking arabinosyltransferase. Optic neuropathy Streptomycin: interferes with 30S of ribosome. Rifampin: Inhibit bacterial DNA dependent RNA pol Also maybe fluoroquinolone.

What does linezolid cause serotonin syndrome?

It has MAO activity so can precipitate serotonin syndrome with use of SSRI

Progressive multifocal leukoencephalopathy

JC virus (polyoma) is often latent in our cells. Most people are asymptomatic. AIDS patients are at high risk for reactivation --> JC attacks oligodendrocytes and so you get this severe demyelinating disease. Presentation: slowly worsening confusion, ataxia, motor deficits, seizure. MRI: areas of white matter demyelination: no mass effect or enhancement. Treatment is to treat the HIV.

Granuloma inguinale

Klebsiella granulomatis. Painless, progressive, red ulcers WITHOUT LAD. Bx: donovan bodies

Levodopa ADE...and what if you add carbidopa

L-dopa causes anxiety and agitation, hallucinations, delusions, confusion, insomnia. n/v, tachyarrhyhtmias, postural hypotension and hotflashes. Adding carbidopa gets rid of the peripheral ADE but it can actually worsen the anxiety and agitation.

Bacillus anthracis

Large, nonmotile, nonhemolytic, gram positive rod that forms colonies in cultures with multiple curls extensions that resemble a "medusa head." Proliferates in soil. Usually affects livestock but infects humans when spores are inhaled/ingested/inoculated. Inhalation --> pulmonary anthrax. Alveolar macs phagocytose the spores and bring to lymph nodes. There the spores germinate into vegetative rods and multiple. They have a *polypeptide capsule made of D-glutamic acid which is antiphagocytic.* Also produce *exotoxin complex* with edema factors that cause cell death (increase cAMP) and lethal factor (protease that causes apoptosis). Non specific initial infection but proliferation in mediastinum can lead to hemorrhagic mediastinitis (widened mediastinum on CXR). Can then spread through bloodstream and cause shock. Often in people who handle hides or animal hair or in cases of biological weapons (open mail). Skin lesion: necrotic ulcer with surrounding erythema and regional LAD. "papule --> ulcer that turns into black eschar"

Strongyloidiasis

Larvae in soil --> penetrate skin --> lungs --> GI tract --> lay eggs in intestinal mucosa. These hatch to rhabditiform (noninfectious) larvae that migrate to lumen and can be excreted in stool. Those larvae can also cause autoinfection and *hyperinfection* (spread throughout body). Can cause multi organ dysfunction and septic shock Most pts asymptomatic but can have chronic, intermittent GI or pulmonary sx. May have pruritic, erythematous, linear streaks on thigh and butt as larva migrate subcutaneously away from perianal region. Dx: *rhabditiform larvae in stool*. Eggs and adult parasites on intestinal biopsy. Rx: ivermectin.

pneumonia + diarrhea + hyponatremia

Legionella. Gram - rod that stains with silver and needs cysteine and iron to grow.. May not show anything on gram stain. Diagnosed with *urine* antigen. Treat with macrolide or quinolone. Suspect in: recent exposure to contaminated water (sporadic or common source like hotel, cruise ship) X-ray evidence of PNA (patchy infiltrates that may progress to consolidation) High fever Sometimes relative bradycardia and neurologic symptoms

High fever with diarrhea, confusion, cough in a smoker

Legionnaires' disease. Common cause of CAP. Contaminates water. Unique lipopolysaccharide chains --> inhibit gra, stain. Treat with: fluoroquinolone or newer macrolide.

Patient presents with blotches of skin with hypopigmentation and patchy areas of anesthesia... what is the microorganism? WHat's the pathogenesis

Leprosy: deforming infection of skin/nerves caused by mycobacterium leprae. Affect the Schwann Cells. Transmission: unhygienic conditions. Respiratory route, skin-skin contact, armadillo contact. Manifestation depends on immune response: 1. Tuberculoid leprosy - not severe and self-limited. Intact cell mediated immune (Th1 mediated) response. Hypopigmentation and focally decreased sensation. Positive lepromin test. 2. Lepromatous leprosy - weak cell mediated immunity response so TH2/antibody mediated. Macrophages signalling to kill it is limited --> dissemination. --> skin thickening, plaque like hypopigmentation, leonine facies, paresis, blindness, testicular destruction.... Organism grows best below core body temp so that's why it affects skin, superficial nerves, eyes, testes.

Leptospirosis

Leptospira: thin, coiled, motile spirochete. Infects wild and domestic animals. Excreted by animals in urines. Humans infected when exposed to water contaminated with animal urine. Often asymptomatic. Can have flu-like illness, LAD, and renal/hepatic failure. Diagnostic clue: conjunctival suffusion: redness of conjunctiva that resembles conjunctivitis but is non inflammatory. Traditional culture media won't work.

Montelukast

Leukotriene antagonist. Used for long-term control in some asthma patients (LKAs are potent inducers of airway bronchoconstriction and inflammation). Possess less efficacy and less anti-inflammatory than inhaled steroids.

Digoxin toxicity

Life threatening arrhythmias, GI, neurologic: fatigue, confusion, weakness, *COLOR VISION ALTERATIONS*. The drug is renally cleared with narrow therapeutic window so toxicity often from alterations in kidney function. Hyperkalemia (inhibition of Na/K ATpase increases extracellular potassium).

Etanercept Infliximab Certolizumab

Links soluble TNF-alpha receptor to Fc component of human IgG1. It's a DECOY RECEPTOR. Infliximab = chimeric monoclonal antibody. Certolizumab: peglyated humanized monoclonal antibody that targets TNF alpha. Lacks Fc --> minimize complement activation and cell mediated toxicity.

What drugs are used for bipolar disorder maintenance

Lithium, valproate, lamotrigine, quetiapine (might use first gen antipsychotics for acute mania but not maintenance)

Treatment of bipolar

Lithium: manic and depressive features Valproate and carbamazepine: manic features Lamotrigine: depressive features

What kind of vaccine for herpes zoster (shingles), varicella, yellow fever

Live attenuated

What analgesic works by blocking voltage dependent sodium channels

Local anesthetics: lidocaine (less sodium influx and AP propagation). Local anesthetics have greater effects on small myelinated nerve (ex. pain and temp... pressure/motor often preserved)

Ehrlichia chaffeensis

Lone star tick bite. Harbored in white tailed deer. Spread to tissue with mononuclear cells. Non specific symptoms (fever, chills, myalgia, headache), maculopapular rash, and significant lab abnormalities *(lymphopenia*, thrombocytopenia, elevated aminotransferases). Mulberry-shaped intraleukocytic inclusions (morulae). Treat with doxycycline.

Physiologic insulin secretion can be approximated by giving

Long acting prep like glargine once daily + rapid acting insulin like lispro with meals.

Treat delirium

Lose dose antipsychotics like haloperidol

Dopamine at various concentrations

Low dose: D1>B1>a1 mild decrease in BP and increase HR. High dose: a1>b1>d1 increase in bp; mild to no change in HR.

Epinephrine receptor binding and effects on SVR, CO, renal blood flow

Low dose: B1>B2>a1. Increases CO and maybe decreases SVR. At high dose: a1>B1>b2: increases SVR, maybe decreases CO, decreases renal blood flow

ADE of first gen antipsychotics

Low potency = non-neurological: sedation (histamine blockade), anticholinergic side effects (cholinergic blockade), orthostatic hypotension (a1 blockage) Chlorpromazine, thioridazine High potency = extrapyramidal symptoms: acute dystonia, akathisia, parkinsonism. - haloperidol, fluphenazine

What indicates excessive use of diuretics

Low urine sodium and elevated BUN/Creatinine. Normal urinalysis. Volume depletion. Excessive diuresis -- renal hypoperfusion --> activate RAAS --> solute/water reabsorption. So: low urine sodium and low fractional excretion of sodium. Increased urea reabsorption. Increased urine osmolarity. Hemoconcentration (increased albumin, hemoglobin, uric acid)

GAS virulence

M protein: inhibits phagocytosis, prevents complement, aids in epithelial attachment. Structural homology to myosin (antibodies against it may cross react and cause rheumatic carditis)

Disseminated gonococcal infection

MCC septic arthritis in young, sexualla active people. Present with purulent arthritis or triad of polyarthralgia, dermatitis (vesiculopustular lesions), tenosynovitis. Or a combo of the two. Joint fluid shows gram - intracellular diplococci (if it was an IV drug user, think s aureus)

Norovirus

MCC viral gastroenteritis. Food or water contaminated with human feces. Vomiting-predominant with watery diarrhea that is NOT inflammatory: no blood/leukocytes.

Encephalitis outbreak (in US)

MCC: arbovirus meningoencephalitis. Febrile illness with signs of meningitis (neck stiffness, headache) and encephalitis (confusion, seizures, tremor). Arboviruses: west nile, la crosse, st louis, EEV,WEV. Small RNA viruses. Harbored by birds and small mammals and transmitted by arthropods. Primarily during summer. Otherwise healthy people: pretty asymptomatic. Humoral antibody response. People who can't mount a rapid, effective antibody response (elderly, immunocompromised) may have persistent and more severe viremia --> flu-like illness that may progress to meningitis or encephalitis. Lymphocytic pleocytosis in CSF. (aseptic meningitis is often caused by enteroviruses - coxsackie/echo virus that are fecal oral...but these usually don't cause sing of encephalitis).

MacConkey agar

MacConkey is selective and differential. Bile salts: prevent gram positive Ferment lactose: local drop in pH --> colonies with pink/red appearance.

Artemisinin-based therapy

Malaria

When do you use tPA in suspected DVT/PE?

Massive DVT at risk of limb ischemia or life-threatening PE with hypotension

Immunoglobulin levels in congenital infections

Maternal IgM does NOT cross placenta...so detection of organism specific IgM in asymptomatic neonate is diagnostic. At birth, all infant IgG is maternally derived IgG that crossed placenta. Maternal IgG, fetal IgM and IgG are the expected findings.

Exacerbation of myasthenia gravis in patients on AChE inhibitors

May occur for two reasons - use Edrophonium (tensilon test): 1. Patient is undertreated. Infusion of short acting AChE inhibitor Edrophonium will temporarily improve symptoms. In this case, you should increase the dose. 2. (Rare). Cholinergic crisis. Too much AChE and excess ACh in cleft --> excessive stimulation of muscles so they become refractory. Also presents with muscle weakness but edrophonium infusion would produce no improvement in symptoms. Rx: temporarily discontinue AChE inhibitors. Remember...myasthenia gravis involves the nicotinic receptors so drops like atropine wouldn't do anything.

Coryza, conjunctivitis, cough, maculopapular rash

Measles. Also koplik spots on buccal mucosa (Pinpoint gray). Rash starts on head and travels down.

Clomiphene citrate

Medication used to induce ovulation. Antiestrogen. Prevents negative feedback in the hypothalamus. So increased LH and FSH release. Used to treat infertility from anovulation (PCOS).

Rapid onset headache, fever, altered mental status, nuchal rigidity, purpuric rash

Meningococcal meningitis. Severity of disease is due to the cell membrane virulence factor: *lipo-oligosaccharide.* This is analogous to LPS on gram-negative enteric rods. These are endotoxins. Binds to toll-like receptor 4 on monocytes and dendritic cells --> release of inflammatory cytokines --> endothelial damage, capillary leakage, hemorrhagic necrosis. N meningitidis capsule is important to resist phagocytosis and complement activation but this does not cause the SHOCK. IgA protease is also released, aids in colonization of nasopharynx. Rx: ceftriaxone or Pen G.

Morphine metabolism

Metabolized in liver via glucuronidation to form: morphine-3-glucuronide and morphine-6-glucuronide. Then renal elimination. The metabolites are metabolically active so renal dysfunction --> metabolite accumulation and opioid toxicity. The morphine-6-glucuronide is especially responsible for toxicity, acting as a more potent mu opioid receptor agonist than morphine itself. Careful monitoring with renal dysfunction! Fentanyl or hydromorphone are preferred in these patients due to predominantly hepatic clearance.

Drugs for pregnancy termination

Methotrexate: ectopic. Preferentially destroys proliferating fetal cells. Mifepristone: Abortion; partial progesterone agonist (acts as antagonist during pregnancy). Promotes placental separation and uterine contractions. Misoprostol: Abortion. PGE1 agonist. Stimulates contractions.

Treatment of Giardia

Metronidazole. Stool: ellipsoidal cysts with smooth, well-defined walls and 2 nuclei

Tinea corporis

Mildly pruritic, polycyclic rash with raised, sclay border and central clearing. Usually skin contact. Trichophyton rubrum dermatophyte. Infection of keratinized matter of stratum corneum of superficial epidermis. Don't invade. Dx with KOH of skin scrapings: segmented hyphae and arthrospores

Use of dobutamine for testing purposes

Mimics the effects of exercise (increase HR and contractility) and increases myocardial oxygen demand. Can provoke areas of ischemic myocardium. In patients with coronary artery disease, will cause a transient decrease in contractility and reduced ejection fraction (blood flow is limited to certain areas so O2 demand can't be met)

Trastuzumab MOA and toxicity

Monoclonal ab against HER2. Inhibits MAPK and P13K/Akt signalling pathways, increases degradation of HER2, and facilitates antibody mediated destruction of tumor cells. Decrease in myocardial contractility without cardiomyocyte destruction or myocardial fibrosis. Reversible with discontinuation of therapy (unlike doxorubicin)O

You get a 44 year old man that seems like he has meningitis. High opening pressure, low glucose, high protein, high neutrophils in CSF. What's causing it?

Morphology on CSF gram stain is much faster than growing a culture. Strep pneumo is the most common cause of bacterial meningitis in adults of all ages: lancet-shaped gram+ cocci in pairs. Increased risk: alcohol, sickle cell, asplenic. S pneumo is the leading cause of community acquired PNA, otitis media, and meningitis in adults. N meningitidis: 2nd MCC. more common in places where people live in close quarters. H flu is less common now because of vaccination. Listeria is common in neonates (after group b strep and e coli). Listeria also causes meningitis in immunosuppressed and elderly.

Treatment of coagulase negative staph (ex. staph epi)

Most are methicillin resistant. (would also be resistant to cephalosporins - altered PBPs). Often also resistant to cipro. Use *Vancomycin.* If it is found to be methicillin sensitive, can use beta lactamase resistant penicillins: nafcillin, oxacillin

Fungal infections in neutropenic patients

Most common: aspergillus, candida. aspergillus way more likely to cause a PNA.

Campylobacter Jejuni

Motile, curved, gram -ve. From undercooked food, domesticated animals (puppies especially). Virulence factors --> Cytotoxic injury --> cramps, abdominal pain, watery diarrhea that MAY be bloody. Inflammatory. Usually results in 3-5 days. May cause Guillain-Barre.

Right-angle branching hyphae

Mucormycosis. Mold infection - spore inhalation. Invasive disease in immunocompromised. Diabetic ketoacidosis and immunosuppression. Tend to affect paranasal sinuses: periorbital pain, headache, purulent nasal discharge. May cause necrosis --> black eschar.

Miliary tuberculosis

Multiple pulmonary lesions and critical illness (fever, night sweats. Not usually calcified.

Pilocarpine

Muscarinic agonist that lowers IOP in glaucoma (contracts ciliary muscle) and contacts pupillary sphincter (closed angle glaucoma). Carbachol too. Pilocarpine is a potent stimulator of sweat, tears, saliva.

Acute salicylate intoxication. 1544. 7557.

N/V, dizziness, confusion, tinnitus, fever, tachypnea. Two acid base disorders: 1. Respiratory alkalosis (salicylates directly stimulate respiratory center). 2. Anion gap metabolic acidosis (salicylates increase lipolysis, uncouple ox-phos, inhibit TCA --> increased unmeasured acids (ketoacids, lactate). So it's mixed: Arterial pH may be normal. Low serum HCO3- and low PaCO2 due to respiratory compensation for the metabolic acidosis and the respiratory alkalosis. Because it's mixed, PaCO2 is lower than expected for respiratory compensation alone. When you see an overdose, consider this as a possibility. Treatment: Sodium Bicarbonate 1. Binds free hydrogen ions in the blood. Facilitates conversion of lipophilic salicylic acid to a lipophobic salicylate ion: trapping it in the blood. 2. Alkalinizes the urine to facilitate conversion of salicylate and its metabolites to lipophobic ionized form, which reduces reabsorption and increases urinary excretion.

PCP

NMDA glutamate antagonist. Hallucinations, aggression, nystagmus. (LSD doesn't have nystagmus)

Treat alcohol use disorder

Naltrexone: blocks mu receptor. Inhibits rewarding aspects of alcohol --> reduce craving. Can give long-acting depot forms. Acamprosate: modulating glutamate neurotransmission at NMDA Second linge: Disulfiram: inhibits aldehyde dehydrogenase; poor efficacy (depends on supervised administration)

Warfarin teratogenic effects

Nasal hypoplasia, stippled epiphyses

Hookworm infection

Necator americanus and Ancylostoma duodenale. Topical and subtropical regions. Walking barefoot on the beach --> come into contact with larvae. Dermal penetration results in transient pruritic, maculopapular or serpiginous rash at entry site. The larvae spreads blood --> lungs --> intestine. Mature into adults in intestine and feed on human blood. Can cause *microcytic anemia.* May develop transient pulmonary symptoms. Dx: smooth, thin-walled hookworm eggs in stool microscopy. Adn peripheral eosinophilia.

What are some prominent intracellular bacteria?

Neisseria, listeria, Mycobacterium tuberculosis (protected from immunoglobulin)... others: chlamydia, francisella, legionella, nocardia, rickettsia, salmonella typhi, yersenia pestis

Neonate with tachypnea, grunting, subcostal retractions.

Neonatal sepsis. Gram positive rods: Listeria monocytogenes. Acquired after delivery or transplacental. Occurs in the first few hours of life.

Phenytoin teratogenic effects

Neural tube defects, microcephaly, facial clefs, dysmorphic face, digital/nail hypoplasia

Oseltamivir

Neuraminidase inhibitor used for flu A and B. Required for release of virus. Can also be used as ppx by impairing penetration

Drugs to stop preterm labor

Nifedipine (CCB) and indomethacin (COX inhibitor). Tocolytic. Decreased intracellular calcium from nifedipine blocks myosin kinase phosphorylation --> myometrial relaxation. Indomethacin stops prostaglandin synthesis, which decreases uterine contractility. And terbutaline: b2 agonist.

Heart drugs that increase cGMP

Nitrates-by activating guanylate cyclase. Get dephosphorylation of myosin light chains and vascular smooth muscle relaxation.

What drugs cause methemoglobinemia?

Nitrites, benzocaine. Cyanosis and chocolate colored blood. Treat with methylene blue and vitamin C.

Treatment of acute simple cystitis

Nitrofurantoin or TMP-SMX.

Treatment of cocaine intoxication

Nitroglycerine (decrease preload) and benzodiazepines (decrease sympathetic outflow) to improve myocardial ischemia

nitroprusside vs nitroglycerin

Nitroprusside is a potent arterial and venous vasodilator (decreases preload and afterload - maintain CO; no change in stroke volume). It produces more balanced arterial and venous dilation compared to nitroglycerin (which is more of a venodilator particularly at low doses). Nitroprusside = generate NO in bloodstream rather than venous smooth muscle. Nitrates = nitroglycerin, isosorbide mononitrate, isosorbide dinitrate.

Do you give steroids and abx for all meningitis?

No - just strep pneumo. It reduces inflammation.

Does lithium cause SIADH?

No it causes nephrogenic diabetes insipidus: don't respond to ADH so you pee a ton. Serum sodium/osmolality increase.

Labetalol

Non-Selective Alpha/Beta Antagonist. a1 antagonism>b2 antagonism --> peripheral vasodilation. Decrease BP without reflex tachycardia.

Patiromer

Nonabsorbable cation exchange resin that binds colonic potassium in exchange for calcium, trapping K+ in the resin where it is then excreted in feces. Used for chronic hyperkalemia. Sodium zirconium cyclosilicate acts very similar. ADE: diarrhea, hypokalemia, hypercalcemia, hypomagnesemia.

Buspirone

Nonbenzodiazepine anxiolytic used for generalized anxiety disorder. No risk of dependence. Primarily affects serotonin receptors.

Tubocurarine

Nondepolarizing neuromuscular blocker. Muscular paralysis via competitive antagonist with ACh receptor sites in NMJ. No effect on presynaptic nerve...it'll continue to be active. Paralysis of diaphragm if not mechanically ventilated. Reverse with neostigmine.

HPV structure

Nonenveloped dsDNA

School outbreak of acute vomiting and diarrhea. Watery without blood or mucus. Some are febrile. No travel history. Up to date with vaccinations...what is it? What is it not?

Norovirus: MCC of viral gastroenteritis. Diarrhea, vomiting, fever, malaise, headache. Watery and without blood or mucus because no small bowel inflammation. Resistant to acid, bile, pancreatic enzymes so easily transmitted fecal-oral. Often causes outbreaks in crowded settings. Not adenovirus: can have fever and watery diarrhea but does not usually cause outbreaks (but it can). Most commonly causes pharyngoconjunctivitis and coryza (runny nose, nasal congestion). Not ETEC: this is traveler's diarrhea. Not rotavirus: they're vaccinated.

Metabolism of monoclonal antibody drugs

Not eliminated by liver or kidneys. 1. Target-mediated drug clearance: internalization upon binding. 2. Nonspecific clearance: Igs are constitutively taken up by RES macrophages (Fc receptors) and vascular endothelial cells (pinocytosis). Once taken up, they're catabolized into amino acids within lysosomes.

Treat beta blocker overdose

OD:depression of myocardial contractility, brady cardia, AV block--> low CO. Treat with GLUCAGON.

CMV esophagitis

Occurs in immunocompromised patients. Presents with odynophagia (pain iwth swallowing) and burning chest pain. Will have linear and shallow ulcerations in lower esophagus. Bx will show intranuclear inclusions

Shiga Toxin and shigalike toxin

Of Shigella and EHEC, respectively. Inactivates 60S ribosomal subunit

Drug induced hemolytic anemia

Often due to anti-inflammatories, penicillin, cephalosporin. Those abx bind surface of RBC and create hapten for IgG attachment --> extravascular hemolysis by splenic macrophages. Positive direct coombs.

What do HSV-1 and 2 cause?

On lips - usually HSV-1. On genitals - usually HSV-2. But both can cause either. Temporal lobe encephalitis - HSV-1 Meningitis - HSV-2 Neonatal herpes - HSV-2 The rest caused by HSV-1

Phenylephrine site of action

Only a1. Increase SVR but lowers CO and renal blood flow (drugs that increase bp by increases SVR = pressors; useful in septic shock)

Treatment of acute opioid withdrawal in neonates

Opiate replacement with morphine or methadone.

Morphine and opiod receptors

Opiate. Opiate receptors: mu, delta, kappa. All mediate analgesia at spinal and supraspinal levels. All coupled to Gi. Morphine and other common opiates have highest affinity for mu. Mu: on primary afferent neuron --> close voltage gated calcium channels --> less NT release from presynaptic terminal. Also on postsynaptic membrane and open K+ channels leading to K+ efflux.

Loperamide

Opioid agonist. Antidiarrheal. Binds mu receptors in colonic myenteric plexus. This inhibits Ach release from neurons --> slows peristalsis --> more water absorption. Unlike other opiates, this undergoes high first-pass metabolism and doesn't cross BBB. Diphenoxylate is another opiate used for diarrhea. It is often combined with a little atropine (causes dry mouth) to prevent abuse. This one does cross BBB.

Diphenoyxlate

Opioid antidiarrheal. Binds mu opiate receptors to slow motility. Often combined with atropine to discourage abuse (causes ADE).

What opiate can precipitate withdrawl?

Opioids selectively bind GPCRs. Long term activate of mu --> increased pain sensitivity (central sensitization) due to : receptor downregulation and recoupling and upregulation of NMDA receptors. So you need higher dose for same level of pain relief (tolerance) and pain sensations triggered by benign stimuli (opiod-induced hyperalgesia). Opioid withdrawal occurs 24-48 hours after acute cessation. *Buprenorphine* is a partial opioid agonist with low intrinsic activity for mu-receptors. But it binds with high affinity and can prevent binding of other opiods. So it acts as an antagonist in the presence of full agonists.

MCC overdose death

Opioids: ex. prescription analgesics and heroin

Treatment of children with watery diarrhea

Oral rehydration solution containing hypotonic, equimolar concentrations of sodium and glucose to prevent dehydration and electrolyte abnormalities. (need glucose to transport sodium across, then water will follow)

RNA viruses in nucleus

Orthomyxo and retrovirus

Which viruses have segmented genomes? What's the significance

Orthomyxovirus, rotavirus. Also reovirus, bunyavirus, arenavirus. This al ows them to undergo reassortment of genomic segments with other viruses.

Differentiation of non-lactose fermenters GNRs

Oxidase test: Positive: pseduomonas Negative: --> TSI agar No H2S production: Shigella H2S production (black color): salmonella

paramyxoviruses

P = parainfluenza R = RSV M = measles (rubeola), mumps

Theophylline

PDE inhibitor. Increases cAMP. So it's a bronchodilator sometimes used in asthma.

Milrinone

PDE-3 inhibitor. Inhibits cAMP degradation --> *increased cardiac contractility* (increased Ca2+ influx due to cAMP) and *vasodilation* (due to increase cAMP --> MLCK inhibition). Used in refractory heart failure due to left ventricular systolic dysfunction

Treat actinic keratoses

PGE2 is involved in tumorigenic effects of UV light, promoting formation of AK and SCC. Topical diclofenac (NSAID) can be used.

H Pylori treatment

PPI + clarithromycin + amoxicillin, with or without bismuth.

Antithyroid drugs ADE

PTU, methimazole. Inhibit thyroid peroxidase. Increased risk of agranulocytosis, likely due to immune mediated effects and direct bone marrow toxicity. Increased risk for severe infection. *Methimazole is a teratogen.* *PTU causes hepatic failure.* PTU can cross the placenta and inhibit production of T4.

Mucor presentation

Paranasal infection in immunocomp/diabetes. Broad, ribbon-shaped, non-septate hyphae that branch at wide angles/

Schistosomiasis - what it causes - dx - rx

Parasitic blood fluke in Africa and East Asia. Exposure in freshwater with snails - penetrate the skin. Migrates to liver --> mature into worms. Mansoni/japonicum --> mesenteric venules Haematobium --> bladder The mansoni/japonicum eggs can trigger granulomatous inflammatory response --> GI sx (diarrhea, weight loss, anemia), bladder (hematuria), periportal system (portal htn, splenomegaly). Eosinophilia is common. This is a Th2 mediated granulomatous response Dx: ID of round/oval eggs with a characteristic terminal (haematobium) or lateral (mansoni) spine on stool/urinary testing. Rx: Praziquantel This is an infection that can go on for months... whereas something like Entamoeba histolytica would be more acute

Hep B structure / replication

Partially dsDNA progeny. A DNA virus that uses reverse transcription to generate new viral DNA from a positive sense RNA template. Hep B can incorporate into the genome. This promotes tumorigenesis. Produces oncogenic viral proteins: HBx --> transcriptional activator of cell growth and interferes with p53.

Gram negative rod with bipolar staining

Pasteurella multocida. Catalase+, oxidase+. Encapsulated. Treat with penicillin and beta lactamase inhibitor. Cellulitis and osteomyelitis.

Letrozole

Patients with PCOS --. increased ovarian estrogen --> inhibits FSH, LH, ovulation. Ovarian estrogen production occurs by conversion of androgens into estrogens. Letrozole inhibits aromatase --> suppress ovarian estradiol production. Also inhibits aromatase in adipose. Result: more FSH, LH --> ovulation. Clomiphene is another drug that can stimulate ovulation. It acts on estrogen receptors in hypothalamus and pituitary. It stops release of GnRH, FSH, LH. Depletes estrogen receptors in those places --> continued FSH and LH release.

What happens after you treat syphilis?

Penicillin. Jarisch-Herxheimer reaction. Acute febrile syndrome within a few hours (up to 48). Due to rapid lysis of spirochetes --> bacterial lipoproteins into bloodstream --> strong innate immune response. Usually self-limited. Can occur for all spirochetes: syphilis, Lyme disease, leptospirosis.

Treatment of pseudomonas

Penicillins: pip-tazo, quinolones: cipro, levo, and aminoglycosides

Mixed agonist/antagonist opoioids

Pentazocine: k-agonist and mu weak antagonist/partial agonist. Butorphanol: k-agonist; mu partial agonist. Used for pain. Can cause withdrawal if patient is also on agonist.

Vibrio vulnificus

People with chronic liver disease are at increased risk. Ingestion of pathogen usually results in severe, rapid onset sepsis in susceptible patients. More likely to cause wound infections than gastroenteritis. Associated with oysters, shellfish.

Bacterial cell wall

Peptidoglycan. Composed of linear glycan of 2 alternac sugars, N-acetylglucosamine and N-acetylmuramic acid that are cross-linked by short peptides. The enzyme *glycosyltransferase* is a crucial component of peptidoglycan synthesis. Mycoplasma species (ureaplasma urealyticum, M hominis) completely lack a cell wall. Only have a single phospholipid bilayer composed primarily of cholesterol. So anything that affects the cell wall wouldn't affect these. Need to inhibit ribosome function.

Properties of drugs: - Permissiveness - Additive - Synergistic - Tachyphylaxis

Permissiveness: When a hormone has no direct effect on a physiologic process but allows another hormone to exert its maximal effect on that process (ex. cortisol and NE) Additive: 1+1 = 2 Synergistic: 1+1 = 3. Tachyphylaxis: decreased drug responsiveness in a short period following 1+ doses.

Pharyngitis + lymph nodes + fatigue

Pharyngitis + lymph nodes + fatigue = mono.

MAOIs (for depression)

Phenelzine, trancyclopromine. Isocarboxazid, Selegiline. Increase presynaptic availability of serotonin, NE, dopamine. May be used in treatment-resistant MDD. Especially MDD with atypical features: mood reactivity (improves with positive events), leaden paralysis (feel very heavy), rejection sensitivity, increased sleep and appetite. (selegiline and rasagiline inhibit MAO-B in CNS)

MOA of antiseizure drugs: phenytoin, carbamazepine, valproate, benzo/barbiturates, levetiracetam, ethosuximide

Phenytoin/carbamazepine: block Na+ channels. Valproate: block Na+ and increase Gaba Benzo/barbiturates: increase GABAa action Levetiracetam: modulate GABA and glutamate release Ethosuximide: block thalamic T-type calcium channels

rhinovirus is

Picornavirus

Heparin induced thrombocytopenia

Platelet destruction that arises secondary to heparin therapy. Get thrombosis actually (rather than bleeding). Use direct thrombin inhibitors to treat. (example presentation: pt getting treated for unstable angina develops severe foot pain and right toe paleness and his platelets are low).

Insulin types

Postprandial short-acting: Lispro, aspart, glulisine (peak .5-3 hours) Regular (peak 2-5 hrs) - use IV for DKA Basal intermediate: NPH - twice daily Basal long acting: Glargine, detemir, degludec

Firm, dome shaped, flesh colored papules with central umbilication and nontender

Poxvirus Molluscum Contagiosum. Biopsy: intracytoplasmic eosinophilic inclusion bodies.

MOA of ACEI

Prevent angiotensin 1 to 2. So this prevents efferent arteriole from constricting more than AA --> so it decreases GFR. Creatinine will rise. ADE: angioedema, cough. (ARBs should not cause cough)

How do cationic exchange resins (cholestyramine) affect cholesterol and TGs? And what's the MOA?

Prevents bile acid reabsorption. Decrease cholesterol but increase TGs. These bing bile acids in GI tract and interfere with enterohepatic circulation --> increased bile acid secretion. So you get synthesis of new bile acids, a process that consumes liver cholesterol stores. So hepatic LDL uptake is increased. The decreased hepatic cholesterol activates HMG CoA reductase --> increased hepatic cholesterol synthesis. So, give it with a statin for synergy. Increase hepatic production of TGs and increase release of VLDL --> hypertriglyceridemia

Mifepristone

Progesterone antagonist. Used for medical abortion.

Sirolimus

Proliferation signal inhibitor targeting mTOR. Blocks cell growth/proliferation. Specifically, it binds FKBP and forms a complex that inhibits mTOR. Leads to disruption of IL-2 signal transduction --> prevents G1 to S progression.

staph aureus virulence

Protein A in outer peptidoglycan layer. Binds Fc portion of IgG at the complement binding site, preventing activation. --> decreased c3b --> impaired opsonization and phagocytosis. Hemolysin: destroys immune cells

Succinyl choline was used for intubation but paralysis persists hours later

Pseudocholinesterase deficiency. Autosomal recessive. Succinylcholine acts as a competitive agonist of nicotinic acetylcholine receptors. Hydrolyzed by plasma pseudocholinesterase. Usually has duration of less than 10 minutes Deficiency --> can't metabolize --> lots of drug at NMJ. Longer paralysis.

What kind of disease does blastomycosis cause? Tell me more about this...

Pulmonary that may disseminate to bone/skin. Will form granulomatous nodules. Ohio and MS river valleys, *great lakes*. found in soil. DIMORPHIC!! Culture (25˚C): branching hyphae Biopsy: large, round yeast with doubly refractile wall and single broad-based bud

Gemcitabine

Pyrimidine analog (like cytarabine) but also inhibits ribonucleotide reductase

Drugs that inhibit purine/pyrimidine synthesis

Pyrimidine: Leflunomide: inhibits dihydroorotate dehydrogenase (carbamoyl phosphate --> orotic acid). 5-FU (and its prodrug capecitabine): inhibit thymidylate synthase by forming 5-F-dUMP so don't get dTMP. Purine: 6-mercap and its prodrug azathioprine: inhibit de novo synthesis (watch out with XO inhibitors). Mycophenolate and ribavirin: inhibit inosine monophosphate dehydrogenase (IMP --> GMP) (this drug is much more specific for lymphocytes - relatively absent purine salvage pathway) BOTH: Hydroxyurea: ribonucleotide reductase Methotrexate, TMP, pyrimethamine: inhibit DHFR so less dTMP in humans, bacteria, and protozoa, respectively.

Strep pyogenes virulence factors

Pyrogenic: superantigen AKA exotoxin A, induces fever and shock. Associated with scarlet fever and strep toxic shock syndrome Streptolysin O&S: Damage RBC membranes --> beta hemolysis. Hyaluronidase: spread thru deep layers of skin. M protein: evade phagocytosis and prevent complement Hyaluronic acid capsule that's NOT immunogenic.

8869. So a patient with a fib and is on a drug for it. At rest they have normal QRS duration. In exercise, QRS duration is increase. What's up?

QRS duration normally is reduced during exercised due to increased conduction velocity that accompanies faster heart rates. This patients findings suggest that the drug lengthens the QRS duration in a rate-dependent manner (use-dependence). = Flecainide. Flecainide: 1C antiarrhythmic. Used for supraventricular tachycardias like a fib. These bind to fast sodium channels responsible for phase 0 depolarization in myocytes --> block inward sodium --> prolongs QRS duration with little effect on total action potential or QT interval duration. Class 1C drugs are slowest of class 1 agents to dissociate from sodium channel --> use dependence: sodium-blocking effects intensify as the heart rate increases due to less time for medication to dissociate from the receptor.

Eosinophilic inclusion bodies in cytoplasm of hippocampal and cerebellar neurons

Rabies Negri bodies! I believe poxvirus also has eosinophilic inclusions but this isn't in brain.

Raloxifene vs Tamoxifen

Raloxifene > antagonist at breast/uterus, agonist at bone (osteoporosis); tamoxifen > antagonist at breast, agonist at uterus/bone (breast cancer). BOth can cause hot flashes, VTE. Tamoxifen --> endometrial hyperplasia and carcinoma.

Diagnosis of acute strep pharyngitis and determine need for abx

Rapid antigen detection testing for GAS antigens. Throat culture on blood agar. Antibody tests not use bc antibodies take weeks to form.

Management of (esophageal) varcieal hemorrhage

Rapid lowering of portal pressure. Somatostatin and octreotide inhibit release of hormones (glucagon, VIP) that induce splanchnic vasodilation --> reduce portal blood flow.

Nitroglycerin

Rapid-acting venodilator. Decreased preload and CO. Only minimal arterial dilation. Use to reduce myocardial oxygen demand in acute coronary syndrome.

Scabies

Rapidly spreading, pruritic rash with erythematous papules and excoriations on extremities. Mites burrow into skin and spread person-to-person. Usually presents with intensely pruritic rash on flexor wrist, lateral fingers and finger webs. Often worse at night (delayed type 3 hypersensitivity). Can also involved other body parts (axillary folds). Skin excoriations with small,crusted, red papules May have vesicles, pustules, wheals, and linear burrows. Dx: skin scraping with mites, ova, feces.

Dengue

Recent travel. ssRNA virus with 4 serotypes. *Primary* (first) infection can be *asymptomatic*/self-limited. Symptomatic: fever, headache, retro-orbital pain, *bleeding* (epistaxis, petechiae/purpura), diffuse macular rash, muscle/joint pain (bone-break fever), *leukopenia, thrombocytopenia*, elevated liver enzymes. Primary infection --> lifelong immunity against that serotype. *Secondary infection with a different serotype --> more severe illness*, possibly due to antibody-dependent enhancement of infunction, enhanced immune complexes, accelerated T-cell responses. Dengue hemorrhagic fever, which can be a serious manifestation of secondary infection is due to increased capillary permeability and can get *thrombocytopenia, prolonged fever, shock*. Also more hemorrhagic tendencies: petechiae with tourniquet application, spontaneous bleeding.

How do beta blockers lower bp?

Reduce contractility and heart rate Decrease renin release by kidney (b1 receptors on JG cells) --> less AT2 vasoconstriction and aldosterone water retention

Metformin

Reduces hepatic gluconeogenesis via mGPD and action of glucagon. Also increases glycolysis and peripheral glucose uptake (increased insulin sensitivity). Increased AMPK activity decreases lipogenesis. Measure baseline renal function before treatment (serum creatinine). ADE: diarrhea, lactic acidosis, B12 deficiency. Modest weight loss due to decreased appetite and decreased absorption of glucose.

Gram negative sepsis

Release of lipopolysaccharides from bacterial cells. Lipid A is the toxic component. Induces widespread release of IL-1, TNF-alpha. Causes septic shock. Other components of LPS: O antigen (for identification), core polysaccharide.

Why does niacin cause flushing and warmth and itching?

Release of prostaglandins. Give aspirin an hour before to reduce these side effects.

Treatment of patients with Tb and HIV

Replace Rifampin (induce CYP) with rifabutin. Because rifampin will decrease serum levels of protease inhibitors (cyp inhibitors)

What are MRSA strains resistant to? what are they sensitive to? How did they get this way?

Resistant to oxacillin, nafcillin, methicillin, and all beta-lactams (penicillin, cephalosporins (except ceftaroline), and carbapenems). Methicillin resistance bia alterations in penicillin binding proteins. Reduced affinity for beta-lactam abx. (nafcillin, oxacillin, methicillin are penicillinase stable)

Pralidoxime

Reverses AChE inhibitor binding to Ach-->allows AChE to function normally again. Use = tx of organophosphate/AChE inhibitor poisoning This is the ONLY med that reverses both the muscarinic AND nicotinic side effects of organophosphates!!! (Atropine only reverses muscarinic side effects)

Pt develops fever, headache, myalgia and maculopapular rash after camping in the Appalachian mountains. Bug? Treatment?

Rickettsia rickettsii: gram negative intracellular. ROCKY MOUNTAIN SPOTTED FEVER. Tick bite. The organism has affinity for vascular endothelial cells --> vasculitis (rash is vasculitis). Rash often begins on ankles/wrists and spreads centrally. Rash starts macular and becomes petechial --> thrombocytopenia. First line therapy is doxycycline: inhibits 30s ribosome. +Weil-felix: cross reacts with proteus.

Patient with tunneled dialysis catheter now have purulent pericarditis. What's the cause? Other causes of pericarditis?

S. aureus. Would also be likely if person had a recent chest surgery or penetrating injury. Strep pneumo is most common in adjacent PNA Candida is seen in patients with significant risk factors for candidemia: parenteral feeding, prolonged steroids, immunosuppression due to malignancy.

Actinomyces vs Nocardia

SNAP: Sulfa for Nocardia; Actinomyces use Penicillin. Actinomyces israelii- oral/facial abscess Nocardia asteroides- soil, pulm infxn, brain infections, skin infections, weak acid fast, immunocompromised patients.

Typhoid Fever

Salmonella typhi or para typhi. Gram negative. Reside in human GI tract. Fecal-oral transmission: food/water contaminated by human feces so usually in developing countries with poor sanitation. Invades enterocytes --> submucosa --> phagocytosed by macrophages but impairs the oxidative burst --> replicates in macs and spreads thru RES --> systemic illness. Week 1: progressive fever, *relative bradycardia*. Week 2: abdominal pain, salmon-colored macules on trunk ("rose spots"), constipation/diarrhea. Week 3: Dissemination thru RES --> hepatosplenomegaly, anemia, *leukopenia*. Ulceration of peyer patches --> GI bleeds and intestinal perforation.

What do you give an old person experiencing a type 1 hypersensitivity reaction

Second gen antihistamines: loratadine, cetirizine. First gen ones (hydroxyzine, promethazine, chlorpheniramine, diphenhydramine) have anti-cholinergic, anti-alpha1-adrenergic, serotonergic effects that aren't great for elderly. First gen can also cross BBB and cause sedation and cognitive dysfunction.

What suggests Benzodiazepine OD?

Sedation with normal vital signs. Reverse with flumazenil. Often used for anxiety disorders and alcohol withdrawl and procedural sedation.

Trazodone. Used for? MOA? ADE?

Sedative antidepressant used for insomnia. Inhibits serotonin reuptake. Causes a1 blockage so this accounts for the orthostatic hypotension and priapism.

Rotavirus

Segmented, non enveloped, dsRNA. Fecal oral. Infectious diarrhea typically in pts under 5. Invades villous epithelium of duodenum and proximal jejunum --> villous blunting (loss of absorptive capacity), proliferation of secretory crypt cells (secretory diarrhea, reduced brush border enzymes. Non-inflammatory --> no fecal leukocytes/ RBCs.

Kaposi Sarcoma transmission

Sexual Contact

Classic source of Hep A

Shellfish. But in general just contaminated food/water.

hydroxyurea for sickle cell

Shifts globin gene transcription form beta globin to gamma globin --> increases hemoglobin F. (also inhibits ribonucleotide reductase)

Infectious dose for GI pathogens - how much are needed to case disease

Shigella: very very low. Only need 10 organisms. Survives stomach acid and bile. Other organisms that you don't need that many: campylobacter, entamoeba, giardia. Need a much higher inoculum of salmonella. Other ones that you need a lot: vibrio, clostridium perfringens, e coli.

Fenoldopam

Short acting, selective, peripheral dopamine-1 receptor agonist. Little to no effect on alpha or beta. Gs. Vasodilation of most arterial beds with corresponding decrease in systemic blood pressure. Renal vasodilation prominents --> increased renal perfusion, increased urine output, and natriuresis. Especially beneficial for patients with hypertensive emergency and renal insufficiency.

PDE5 inhibitors. use and ADE.

Sildenafil, tadalafil. Erectile dysfunction. Increase cGMP in penile corpora --> prolonged tumescence. Also inhibit PDE6 in retina --> bluish discoloration to vision. Can also cause nonarteritic anterior ischemic optic neuropathy --> sudden vision loss

H flu

Small gram negative coccobacillus. Requires X factor (hemantin) and V factor (NAD+). These factors are found in RBCs, so only present in lysed blood agar (chocolate agar). Growth on regular agar requires supplementation. Localized infection caused by unencapsulated/nontypeable strains of H flu. H flu b can also cause this in undervaccinated patients. H flu b: has polysaccharide capsule. Inhibits complement-mediated phagocytosis. Causes meningitis, bacteremia, PNA, epiglottitis. Vaccinated people have antibodies against the capsule. Vaccine is conjugated to protein toxoid to induce T cell-dependent response.

Histoplasma appearance...and tell me more about it

Small oval yeast within macs. Ohio and MS river valleys. Soil, bird, bad droppings. Pulmonary: lung granulomas and calcification. Disseminates: lungs,spleen liver. DIMOPRHIC!! Culture (25˚): branching hyphae Biopsy: Oval yeast cells within macs

Why is neprilysin inhibitor (sacubitril) given with an AT2 receptor blocker?

So neprilysin inhibitor --> increased ANP/BNP --> increased vasodilation and diuresis. BUT: neprilysin also inactivates angiotensin 2, so inhibition of that enzyme would increase AT2. That's why the -sartan is given. Neprilysin inhibits breakdown of ANP/BNP, Angiotensin 2, and bradykinin

When you see hyphae in a biopsy?

So not for blasto, histo, and cocci. These are dimorphic so they grow as mold in nature (hyphae) but yeast in humans). Wouldn't see with candida either: oval budding with pseudohyphae. Crypto has thick capsule so you would see that with india ink. Mucor (and Rhizopus) have hyphae but these are NON-SEPTATE and broad and also wide angle branching. Aspergillus forms septate and thin hyphae with acute branching

Otherwise healthy patient with low grade fever, persistent cough, CXR with bilateral patchy infiltrates. Sputum gram stain has numerous leukocytes but no organism

So this is atypical pneumonia. Causes: mycoplasma pneumoniae, chlamydia pneumoniae, legionella pneumophila. To differ between: Legionella would cause GI symptoms too and be more severe. So these don't have a cell wall...that's why they didn't gram stain. You treat with a drug to inhibit protein synthesis..like macrolide or tetracycline

Treat ascites in cirrhosis

Splanchnic vasodilation decreases systemic vascular resistance --> activates RAAS --> vasoconstriction and water retention. Use spironolactone, an aldosterone antagonist, to induce natriuresis and resolve ascites without blocking critical vasoconstrictive effects of angiotensin. Spironolactone often combined with furosemide. Need angiotensin vasoconstriction to main organ perfusion due to splanchnic vasodilation from the ascites. These patients have normal sodium levels so don't use ADH inhibitors. ADH inhibitors treat severe hyponatremia.

Relevant dimorphic fungi

Sporothrix Histo Blasto Cocci Paracocci These will be different shapes at different temps. Mold at 25. Yeast at body temp (37).

Organisms that cause infection in cystic fibrosis patients

Staph aureus pseudomonas aeruginosa h flu burkholderia cepacia (gram negative) Put sputum culture on: regular blood: strep chocolate: h flu macconkey: pseudomonas mannitol salt: s aureus and b cepacia selective agar

Treat ADHD

Stimulants: block NE and Dopamine reuptake. And increased release of NE and dopamine from presynaptic storage and inhibit MAO.

Penicillin structure

Structurally similar to D-ala-D-ala. Inhibits transpeptidases by covalently binding to active site (Vancomycin is a glycopeptide that *directly binds* d-ala-d-ala --> prevents incorporation of new subunits into the wall; acts at earlier stage than penicillin)

Drugs that increase insulin production

Sulfonylurea 1st gen ( chlropropamide, tolbutamide), sulfonylurea 2nd gen (lgipizide, glyburide) Meglitinides: -glinide ... these close K+ in pancreatic beta cells --> depolarize --> insulin release

Which diabetes drugs have high risk of hypoglycemia?

Sulfonylurea, meglitinides. Esp. in elderly. But sulfonylureas have a much longer half life and are therefore more likely to cause prolonged hypoglycemia. Meglitinides have short half life. Also pramlintide - amylin analog.

Nitrates - MOA, ADE, Avoid in:

Systemic vasodilation (predominantly venodilation) --> decreased LVEDV and wall stress --> less O2 demand. Main ADE: headaches, cutaneous flushing, lightheadedness, hypotension, reflex tachycardia. Avoid in HCM, RV infarction, and those on PDE inhibitors.

Host defense to candida infections

T lymphocytes: SUPERFICIAL candida: oral/esophageal candidiasis, cutaneous, vulvovaginitis. HIV --> low T cells --> increased risk of superficial candida. Neutrophils: prevent HEMATOGENOUS spread of candida. So disseminated candidiasis is more likely in neutropenic/chemo patients --> impaired phagocytosis.

Management of angina

Take aspirin to decrease risk of adverse CV events. It inhibits COX1 in plts --> less TXA2 --> less plt aggregation and vasoconstriction. If aspirin doesn't work, use alternate antiplatelet agents.: Clopidogrel - blocks P2&12 of ADP receptors --> prevents aggregation. It is as effective as aspirin in prevention of CV events and should be used in pts with aspirin allergy.

Environmental radioactive iodine (Iodine-131)...how to treat....and what can it cause

Taken up and concentrated in thyroid gland and can cause hypothyroidism or thyroid carcinoma. Give potassium iodide ppx to protect thyroid from excessive accumulation of radioactive I.

Patient recently started on antiretroviral therapy. Now he has edema, elevated creatinine, decreased phosphorus. U/A shows protein and glucose. Bx shows cytoplasmic vacuolization in proximal tubules and loss of brush border and basement membrane denudation. Intracytoplasmic eosinophilic inclusions in proximal tubules. Normal glomeruli. 15113.

Tenofovir-induced nephrotoxicity. *Proximal tubule dysfunction*. NRTI. Tenofovir is eliminated via proximal tubules. High concentrations can interfere with mitochondrial DNA synthesis and cause cell damage. AKI: elevated creatinine and water retention. Proximal tubule dysfunction: phosphaturia, glucosuria, proteinuria. Those eosinophilic inclusions were giant mitochondria.

Toxoid vaccines

Tetanus, dipthera

Polyvalent cations (calcium, iron) can chelate what drugs and decrease their absorption?

Tetracyclines, fluoroquinolones Levothyroxine, levodopa

Treat PTSD

Therapy. SSRI/SNRI.t

How do bacteria get extended spectrum beta lactamases?

These are produced by gram negative bacteria. Transmitted via plasmids.

P ovale and P vivax (malaria)

These have a dormant hepatic phase (hypnozoite) that can last for several months after return from endemic region, if not treated with primaquine.

What drugs can lead to hyperuricemia and precipitate gout attack

Thiazide diuretics

thiazide + loop diuretics

Thiazides can potentiate the diuretic effect of loop diuretics. Sodium is the major determinant of volume status. Loop diuretics inhibit the Na-k-2Cl is ascending LOH. But some of that Na+ is reabsorbed in the DCT. Use of thiazides to inhibits the NaCl cotransport prevents some of the reabsorption of sodium that's delivered there --> increase total sodium excretion.

Inhibits platelet ADP P2Y12 receptor

Ticagrelor

Presentation of salicylate overdose

Tinnitus Hyperventilation: primary respiratory alkalosis N/V Uncoupling of ox phos --> *hyperthermia* and increased anaerobic metabolism --> increase in *lactic acid* --> elevated anion gap metabolic acidosis. Altered mental status Expect this in adolescents/adults - intentional overdose. Carbon monoxide poisoning: flu-like, headache, altered mental status, lactic acidosis but would NOT expect hyperthermia and tachypnea. Would be uncommon for only one household member to have.

Treat localized candidiasis (like thrush)

Topical antifungals: Nystatin (similar MOA to amphotericin: binds ergosterol and creates pores). This is not absorbed in GI tract - used as oral agent "swish and swallow for oropharyngeal candidiasis.

Etoposide inhibits which topo? What do the topos do?

Topoisomerase 2 inhibitor. Prevents it from sealing the breaks it induces. topo 1 - single stranded nicks to relieve negative supercoiling topo 2 - double stranded breaks to relieve positive and negative supercoiling

Tissue nematodes

Toxocara canis: inflammation of liver, eyes,CNS, heart. Onchocerca volvulus: skin changes, loss of elastic fibers, river blindness...black skin nodules and black site. From female black fly. Loa loa: swelling in skin; worm in conjunctiva. Fly. Diethylcarbamazine Wuchereria bancrofti: elephantiasis. Mosquito. Diethylcarbamazine.

Several ring enhancing lesions

Toxoplasma gondii in AIDS pts --> meningoencephalitis (immunocomp person would have asymptomatic infection). Obligate intracellular parasite. Cat feces --> ingestion of oocytes. Or consumption of undercooked meat. Tachyzoite; intramuscular cyst. Rx: pyrimethamine and sulfadiazine. and leucovorin. Ppx: TMP-SMX (CDR < 100)

Loeffler Syndrome

Transient eosinophilic pneumonitis (dry cough, dyspnea, wheezing) caused by migration of parasitic roundworm larva (ascaris) thru the lungs. Stool: oval egg with thick outer shell and single interior ovum. Seen in travelers to asia/africa/south america. Ingest eggs --> larvae in small intestine --> penetrate wall --> mature in alveoli --> swallowed into GI tract and mature itno long adult worms. Cause GI sx.

CMV in pregnancy

Transmission in 1/3 of cases. Highest risk in 1st trimester. Complications: chorioretinitis (most common), sensorineural deafness, seizures, jaundice, hepatomegaly, splenomegaly, microcephaly.

Human pubic louse

Transmission in sexula contact. Condoms don't prevent. Intense pruritus in pubic area with excoriations from scratching. Axillae may be affected. Treat with topical permethrin: blocks parasite sodium ion conduction.

Abortive treatment for migraines

Triptans (serotonin agonists), NSAIDs, acetaminophen, antiemetics, ergotamine. Severe migraine with n/v: triptans or dopamine blocker (metoclopramide)

Serotonin receptor agonist. How do they work? ADE?

Triptans for migraines. - bind to trigeminal serotonin receptors and inhibit CGRP release from neurons. Also bind serotonin receptors on blood vessel smooth muscle -->intracranial vasoconstriction. ADE: htn, dizziness, chest tightness.

Chagas

Trypanosoma cruzi. Triatomine bug. Central and South America. "thatched roofing" Dilated cardiomyopathy with biventricular failure. *Apical wall thinning* with aneurysm +/- mural thrombus. Ventricular arrhythmias. And megaesophagus and megacolon. Acute phase: asymptomatic or nonspecific symptoms and inflammation/swelling at site of inoculation (can be eye) Chronic phase: immune system eliminates circulating parasites then prolonged asymptomatic phase where there's positive serology but no s/s or parasitemia. Then, decades later, some develop that chronic infection with heart/GI symptoms.

Francisella Tularensis

Tularemia. Ulcer --> macs --> RES --> caseating granulomas and LAD. Treat with streptomycin. Dermacentor ticks. Rabbits. Flies. Aerosol. Gram negative coccobacillus. Facultative intracellular

Vibrio parahaemolyticus

Typically transmitted via seafood (shellfish). Diarrhea-predominant gastroenteritis. Life threatening sepsis in pts with liver disease or hemochromatosis.

Causes and symptoms of laryngotracheitis (croup)

URT sx followed by hoarseness, barking cough, stridor, respiratory distress. Inflamed subglottic tissue: laryngotracheitis. Parainfluenza virus.

Croup

Upper resp symptoms. Barking cough, retractions, inspiratory stridor. Parainfluenza virus. Young kids. Edema of proximal trachea (subglottis). Subglottic narrowing: steeple sign. (Epiglottitis does NOT produce barking cough - commonly in unimmunized children and will also have drooling and tripod positioning).

Imiquimod cream

Used for anogenital warts due to HPV. Used for any derm thing of abnormal cell proliferation: superficial BCC, actinic keratosis. Antiproliferative by activating toll-like receptor 7 --> upregulates NFkB --> increase transcription of proinflammatory genes, activating APS and initiating immune response by NK cells, CD8+, Th1 cells. Stimulates IFN alpha, TNF, IL-1,6,8,12 Also: induces apoptosis via inhibition of BCL-2. Inhibits angiogenesis by downregulating those factors.

Bismuth

Used for diarrhea and dyspepsia. Stimulates intestinal absorption of fluid and inhibits PG synthesis (slows motility)

West Nile virus

Usually asymptomatic but can have a flu-like illness with a rash. Can develop neuroinvasive disease: meningitis, encephalitis, Acute confusion associated with fever, asymmetric lower extremity flaccid paralysis (with LMN signs) (!!), and parkinsonian features. CSF often shows a lymphocytic pleocytosis. Neuroinvasive disease occurs in old people or those that are immunocompromised or previous malignancy. Harbored in *birds and transmitted to humans by mosquitoes*

Prevent neonatal tetanus

Vaccine women who are pregnant/will become pregnant. with inactivated tetanus toxin. Mom would provide transplacental IgG.

Infusion of what drug causes massive histamine release

Vancomycin: red man syndrome. This is not an allergic reaction.

Treat nicotine addiction

Varenicline: partial neuronal nicotinic receptor agonist; prevents nicotine stimulation of mesolimbic dopamine system

Nitrates effects

Vasodilation of peripheral veins and arteries, predominantly venodilation. *BUT THEY ALSO DO SOME ARTERIOLAR DILATION.* --> decreased systemic vascular resistance. Decreased LV wall stress (less preload) Modest reduction in afterload Mild coronary artery dilation (if there's atherosclerosis, they're probably pretty dilated already) and reduction of coronary vasospasm. --> decreased myocardial oxygen demand --> improved exercise tolerance and relief of angina. Activate guanylate cyclase --> convert GTP to cGMP. Increased cGMP --> less intracellular calcium and *activation of myosin light chain phosphatase --> myosin light chain dephosphorylation and muscle relaxation.*

Prolonged use of decongestants (a agonists: phenylephrine, xylometazoline, oxymetazoline)

Vasostrict. Used for decongestion. However, develop tachyphylaxis (rapid declining effect) after several days. Because: decreased production of endogenous NE from nerve terminals (from negative feedback) --> relative vasodilation (remove normal vasoconstrictive tone) --> congestion exacerbation...rebound rhinorrhea: nasal congestion without cough, sneeze, postnasal drip. To treat: stop using the decongestant to restore normal NE feedback.

HIV associated nephropathy

Viral infection of kidney epithelial cells. Hematuria, htn, edema. Focal segmental glomerulosclerosis. Significant interstitial inflammation.

Calcipotriene

Vit D analog used to treat plaque psoriasis. Inhibits T cell and keratinocyte proliferation and differentiation.

What vitamin is useful in the treatment of measles

Vitamin A. Acute measles depletes Vit A --> risk of keratitis and corneal ulceration. And other comorbidities.

Tramadol

Weak opioid agonist. Also inhibits NE and serotonin reuptake. Used for chronic pain. Decreases seizure threshold; causes serotonin syndrome.

Potassium sparing diuretics

Weaker. Act in distal nephron. 1. Triamterene and amiloride - inhibit epithelial sodium channel 2. Spironolactone, eplerenone - aldosterone antagonists --> decreased formation/activity of ENaC and Na/K ATPases. (would want to avoid in someone that is hyperkalemic or on a drug like ACEI that causes hyperkalemia).

ADE of ADHD stimulants

Weight loss, decreased appetite, insomnia.

How would an alpha adrenergic agonist affect SBP, DBP, and heart rate?

Would increase SBP and DBP. There would be a reflexive decrease in HR.

Aeromonas hydrophila

Wound infections after contaminated water. Oxidase positive Non-lactose fermenting. Gram negative rod.

6-mercap metabolism

Xanthine oxidase (inhibitors are allopurinol and febuxostat) and TPMT (many people have mutation--> high risk of toxicity)

Treat BPH

a-antagonists (-osin) - relax smooth muscle 5-a-reductase inhibitors (finasteride) - less DHT, reduces prostate gland size. Takes a few months. Antimuscarinics (*tolterodine*) - for overactive bladder Finasteride works well if patients have epithelial hyperplasia predominance. Some patients have predominant stromal hyperplasia: collagen/smooth muscle so these people wouldn't respond as well. People with smooth muscle predominance respond best to alpha-1 blockers.

Aminoglycosides have big risk of

acute kidney injury

treat bordetella. and its virulence factors

adenylate cyclase toxin, pertussis toxin, tracheal cytotoxin: damages ciliated cells. Treat with macrolides; if allergic: TMP-SMX. Lymphocytosis (because it prevents them from getting to site of infection; don't confuse with virus)

prevent acyclovir induced crystalline nephropathy

adequate hydration

aminoglycosides effective against

aerobes

Secondary bacterial pneumonia

after viral infection. often caused by strep pneumo, staphylococcus aureus, and H. flu. The virus: decreases epithelial cell size, loss of cilia --> promote bacterial colonization. Influenza surface protein neuraminidase cleaves sialic acid off host glycoproteins --> free sugar --> bacterial growth.

Phentolamine

alpha receptor blocker. can be used to counteract NE induced blanching of a vein (extravasation) Can also be used for hypertensive crisis: eating tyramine rich foods with MAOI.

Enterococci treatment

ampicillin + aminoglycoside

Aromatase inhibitors

anastrozole, letrozole, exemestane. reduced synthesis of estrogen from androgens --> suppress estrogen levels in postmenopausal women and slows progression of ER positive tumors. Less effective as monotherapy in premenopausal women as ovarian aromatase is upregulated substantially by gonadotropins.

oxybutynin

anticholinergic (m3). treats overactive bladder.

Motion sickness Rx

antimuscarinic (scopolamine) and antihistamines (meclizine, diphenhydramine, promethazine) with antimuscarinic action

Hydralazine

arteriolar vasodilator. Reflex sympathetic activation --> increased HR.

Nondepolarizing neuromuscular blocking drugs

atracurium. Drugs with -cur-. Competitive ACh antagonist.

Carbamazepine ADE

bone marrow suppression // aplastic anemia SIADH Neural tube defects

Multiple myeloma treatment

bortezomib - blocks proteasome lenalidomide - increase ubiquitination of specific transcription factors. This increases E3 ubiquitin ligase binding to TFs overexpressed in myeloma and targets them for proteasome degradation.

Central venous catheter with parenteral nutrition puts patients at risk for

candidemia

Colistin and polymixin B

cation polypeptides that bind to phospholipids on cell membrane of gram -. disrupt integrity --> leakage of cell components --> cell death use for multidrug resistant pseudomonas

Ezetimibe

cholesterol absorption inhibitor

what cancer drugs cross link?

cisplatin, cyclophosphamide

what kind of heart issue do anthracyclines (doxorubicin) cause? What's the MOA? And how to prevent?

dilated cardiomyopathy. Bind Topo 2 to cleave DNA; generate free radicals. Prevented with dexrazoxane; a chelating agent that blocks free radicals and inhibits topo inhibition in healthy cardiomyocytes.

VZV

enveloped, dsDNA. Respiratory droplets or direct contacts. Initial: varicella - fever, diffuse vesicular rash. Latent in DRG or trigeminal ganglion. May reactivate and get herpes zoster. Vesicular rash. Intranuclear inclusions in keratinocytes and multinucleated giant cells. Acantholysis of keratinocytes and intraepidermal vesicles.

Tertiary syphilis

gummas (chronic granulomas), aoritis (vasa vasorum destruction of *THORACIC* aorta), neurosyphilis (tabes dorsalis), Argyll Robertson pupil (small pupils that accommodate but do not constrict/react [according to wikipedia, known as prostitutes pupils b/c they accommodate, but don't react - not sure what that means) Aortic regurgitation. Mediastinal widening suggests aortic aneurysm.

rifampin for close contacts

h flu and neisseria meningitis (even if previously vaccinated)

Coxsackie virus

hand foot and mouth disease: erythematous oropharyngeal ulcers, maculopapular rash or vesicular lesions on palms and soles. Also: aseptic meningitis, myocarditis, pericarditis, herpangina (mouth blisters and fever)

CMV causes:

healthy - Mono immunocompromised: retinitis (blurred vision, blind spots, flashing lights, fundoscopy: yellow-white, fluffy retinal lesions associated with hemorrhages), pneumonia, esophagitis, colitis, hepatitis. Treat with ganciclovir.

Pyrazinamide ADE

hepatotoxicity hyperuricemia (can exacerbate gout)

Small oval yeast within macrophages

histoplasma

Epiglottis

inflamed epiglottis, inspiratory stridor, drooling, sore throat, dysphagia, respiratory distress. cherry red epiglottis. Haemophilus influenzae. NO cough.

otitis externa

inflammation of outer ear. "swimmers ear." moving the pinna is painful. Malignant otitis externa is a severe infection most commonly see in old diabetics. Caused by pseudomonas aeruginosa

E coli

motile, gram negative. ferments glucose and lactose. grows on macconkey and emb. K1 capsular antigen: major virulence factor for meningitis. LPS Verotoxin (shiga-like) Heat labile/stable toxins P fimbriae: UTIs

Biopsy of herpes STD

multinucleated cells with ground-glass intranuclear inclusions. Usually HSV2.

Bethanechol

muscarinic agonist that stimulates peristalsis in post-op ileus and also treats atonic bladder. Only works at muscarinic, not nicotinic. Not metabolized by cholinesterase.

Atropine

muscarinic antagonist

What kind of virus are orthomyxo (influenza) and paramyxo (RSV)?

negative sense RNA

aminoglycoside ade

nephrotoxic, neuromuscular blockade (contraindicated in myasthenia gravis), ototoxic, teratogen.

Nitrate dosing

nitrate free interval prevents tolerance. do it during night time when cardiac work is the least.

enteropathogenic e coli

no toxins; adheres to surface and flattens villi, prevent absorption. Diarrhea in children. P for pediatrics.

what can mimic tb but with negative ppd

nocardia infection

Parvo B19 infection

nonenveloped ssDNA. Initial infection is a nonspecific viral syndrome. Attaches to RBCs via blood group P antigen. Can then also cause: erythema infectiosum in kids (red rash on cheeks (may spread to body and be "lacy, reticular") and fever. And in adults, can cause acute *arthropathy* (self-limited). That second phase is due to *immune complexes* and the pt is much less infectious. Often implicated in school outbreaks. Fetal infection: interruption of erythropoiesis --> profound anemia and heart failure. Heart failure --> pleural effusions, pericardial effusions, ascites = fetal hydrops. Also pulmonary hypoplasia. In sickle cell --> aplastic crisis. In sickle cell patients: prevents RBC maturation. Form giant pronormoblasts with giant, intranuclear viral inclusions. Drop in hematocrit. Sympatomic anemi.

what causes rebound nasal congestion

oxymetazoline, phenylephrine sprays, oral pseudoephedrine

S aureus soft tissue infections usually:

painful, tender, progress rapidly

What do you give to the fetus of a mom with hep b?

passively immunized at birth with Hep B immune globulin, followed by active immunization with recombinant HBV vaccine.

What drugs induce CYP

phenobarbital, carbamazepine, rifampin, griseofulvin, chronic alcohol, phenytoin Modafinil, St. John's Wort

gingival hyperplasia ADE

phenytoin. due to increased PDGF. Cyclosporine Dihydropyridine CCBs

Dipyridamole and cilostazol

phosphodiesterase inhibitor that increases cyclic AMP, impairing platelet aggregation. also increase vasodilation.

most lung abscesses are:

polymicrobial: oral anaerobes: fusobacterium, peptostrep, bacteroides and aerobes. Common in right lung

Prevent VTE in hospitalized patients

ppx anticoagulant: LMWH (enoxaparin)

at low doses, aspirin

predominantly inhibits COX-1, preventing platelet synthesis of TXA2, which impairs platelet aggregation and reduces vasoconstriction

Prevention of perinatal group b strep transmission

prenatal screening for gbs colonization in maternal vagina and rectum at 35-37 weeks. If GBS+, give intrapartum abx ppx - penicillin or ampicillin- is indicated to prevent neonatal GBS sepsis, pneumonia, meningitis. You would give these towards the very end of the pregnancy..like after the screening... CAMP and hippurate+

5-flouracil (5-FU). 1892. need to fix.

pyrimidine analog that inhibits DNA synthesis by inhibiting thymidylate synthetase. So you have less thymidylate synthetase available for thymidine synthesis. This is less toxic in cells that are deficient in THF. Leucovorin potentiate the cytotoxic action of this drug.

Too much time in basement = risk of ___ exposure

radon --> lung cancer

Management of septic shock

rapid fluid resuscitation to replace intravascular volume and restore perfusion. Use .9% (normal) saline (isotonic crystalloid) or lactated ringer. These remain extracellular.

Teriparatide

recombinant PTH that actually increases osteoblast activity and is used for osteroporosis.

how does ACEI affect GFR? 695.

reduce GFR. Creatinine will increase in patients with bilateral renal artery stenosis. Urinalysis unremarkable.

treatment for pitting edema due to cirrhosis, heart failure

restrict salt, restrict water (increased total body water and increased total body sodium) and diuretics

Endocarditis in IVDU

right sided endocarditis; usually staph aureus; also enterococci and strep (not candida). Lungs may show bilateral peripheral opacities: septic embolization to lungs

parasite eggs in stool

schistosoma mansoni or japonicum

Zika virus

ssRNA Flavivirus. Neurotropic. Crosses the placenta and destroys fetal neural progenitor cells. Disruption of normal proliferation, migration, and differentiation. Newborns: microcephaly, contractures, seizures, ventriculomegaly, hypotonia, ocular abnormalities. Loss of brain mass and subcortical *calcifications*. Dx with Zika RNA.

Cause of hematogenous osteomyelitis in otherwise healthy kid

staph aureus

differ staph epi from staph sapro

staph sapro: resistant to novobiocin. staph epi: novobiocin sensitive (hemolysis is a feature of strep (streptolysin O and S) and staph aureus (hemolysin))

Acyclovir MOA and ADE

used for HSV. Use for chronic daily suppressive therapy to prevent recurrent episodes. A nucleoside analog that is converted by HSV virus encoded thymidine kinase. Then cell enzymes convert the monophosphate to triphosphate. Then it gets incorporated into DNA. Renal toxicity Valacyclovir is acyclovir prodrug with better oral bioavailability. Famciclovir also an option.

flaviviruses

west nile st louis hcv dengue yellow fever zika

How would treatment with hydralazine, phentolamine, or nitroprusside affect BP/heart rate

would decrease BP and HR would subsequently increase (reflex)

Loop Diuretics Adverse Effects

■ Electrolytes (HYPOkalemia, HYPOnatremia/low sodium, low levels of chlorine). - sodium and water loss --> aldosterone mediated renal excretion of H+ and K+. Relatively greater loss of Cl- than Na+ --> decreased total body electronegativity --> retain more HCO3-. = metabolic alkalosis. Treat that with carbonic anhydrase inhibitors. ■ HYPOvolemia and HYPOtension (dizziness, lightheadedness). ■ Pancreatitis, jaundice, rash. ■ Ototoxicity (worsens aminoglycoside ototoxicity effect if combined). ■ Be careful with GOUT diuretics can cause HYPERuricemic states due to fluid loss.

Treatment of aortic dissection

(pt with severe chest pain radiating to back; widened mediastinum on cxr; hx of uncontrolled htn). Therapy: reduce aortic wall shear stress to limit extension of dissection. Use anti-impulse therapy to decrease the rate of change in aortic bp per unit time. Esmolol is a b1 blocker that is first line (short half life). It: decreases LV contraction velocity decreases heart rate. Once the shear stress is decreased, vasodilators may be added (don't give them first bc they can cause reflex tachy) (these actions are decreasing the myocardial O2 demand, but the GOAL of therapy for aortic dissection is to reduce aortic wall shear stress).

Sporothrix shenckii

*Dimorphic fungus*. Thorn prick. Usually form a granuloma at lesion. Also neutrophilic microabscesses. Spreads along lymphatics. Dx by culturing affected area. Culture (25˚C): branching hyphae Biopsy: round or cigar-shaped budding yeasts Treat: itraconazole.

TMP-SMX ADE

*SJS-TEN, N/V, folate deficiency (megaloblastic anemia), hyperkalemia* (trimethoprim inhibits epithelial Na+ channel in DCT and collecting duct --> impaired Na/K exchange)

Treatment of painful diabetic neuropathy

*SNRI* (increase *NE* in central synapse), *anticonvulsant gabapentinoid* (pregabalin, gabapentin) (inhibit release of excitatory NTs by binding to voltage gated Ca2+ modulators on nerve terminals), or *TCA* (*blocks voltage gated Na+ channels in sensory nerves,* blocks NMDA in spinal cord, increased *NE* signalling in CNS)

Benzodiazepine withdrawal

*Tremor, anxiety*, perceptual disturbances, *psychosis*, insomnia, *seizures*, tachycardia, palpitations. *Sympathetic hyperactivity.* Risk is greater with short acting agents: alprazolam.

toga viruses

+sense enveloped RNA: Rubella, VEE, WEE and Chikungunya fever (can get co-infection of chikungunya and dengue)

Coronary Steal

- *dipyridamole, adenosine* injected (*coronary vasodilator*) - myocardial perfusion scanning - BF redistributes to "non diseased" areas induced by the drug Areas with atherosclerosis are already vasodilated. SO when you give a vasodilator, those places can't vasodilate anymore but other vessels dilate and will reduce flow to the ischemic areas.

Phenytoin ADE

- CNS manifestations: affects the cerebellum and vestibular system. Ataxia and nystagmus. - Gingival hyperplasia, coarse facial features, hirsutism. - Megaloblastic anemia (interferes with metabolism of folic acid).. - Induces CYP p450. Increases metabolism and decreases blood level of many drugs - Teratogen: fetal hydantoin syndrome.

Renal SGLT2 inhibitor - drug, moa, side effects

-Gliflozin. Decrease renal glucose absorption. Dependent on glomerular filtration of glucose (decreased in CKD) so get a creatinine before therapy. Can cause UTIs and moderate osmotic diuresis --> hypotension (can have orthostatic hypotension). Also weight loss.

Thiazolidinediones

-glitazone. Bind PPAR gamma. Upregulated: Glut-4, adiponectin (cytokine released by fat tissue that increases the number of insulin responsive adipocytes and stimulates fatty acid oxidation) (ppar alpha is acted upon by fenofibrate, gemfibrozil. ppar play a role in pathogenesis of metabolic syndrome) ADE:Fluid retention due to increased sodium reabsorption. Thi can cause weight gain, edema, and decompensation of heart failure. Also adipose weight gain.

Opportunistic diarrhea in HIV

1. CMV (most common)- ulcers/erosions in colon. Large cells with basophilic intranuclear and intracytoplasmic inclusions 2. Cryptosporidium - *nonulcerative*; basophilic cluster on surface of intestinal (not colon!) cells. Modified-acid fast. (pictured) 3. Microsporidium - distortion of villus architecture without inflammation. Small spores with diagonal or equatorial belt-like structure 4. Mycobacterium avium - necrotizing and non-necrotizing granulomas. acid fast.

Ionizing radiations (gamma rays, x rays) used to treat cancer work by:

1. DNA double strand breakage 2. Free radical formation

ADE of HIV protease inhibitor

1. Lipodystrophy: "buffalo hump" and central obesity 2. Hyperglycemia (increased insulin resistance; may lead to diabetes). 3. Inhibition of Cyp P450 --> drug-drug interactions.

Increased infection risk in patients undergoing chemo

1. Mucositis - damage to rapidly dividing cells in GI tract --> breaches in mucosal barrier --> endogenous bacteria enter the bloodstream (p aeruginosa, and skin staph epi/staph aureus are most likely). 2. Neutropenia so *endogenous commensal pathogens* that penetrate the mucosal/cutaneous barrier can't be contained --> spread to blood and tissue. Weak inflammatory response and fever. Fever is only sign of infection --> neutropenic fever. To reduce risk: ppx abx and granulocyte-stimulating agents to increase neutrophils

Absolute contraindications to the use of OCPs

1. Prior history of thromboembolic event/stroke 2. History of estrogen dependent tumor 3. Women over 35 that smoke heavily 4. Hypertriglyceridemia 5. Decompensated or active liver disease (impair metabolism) 6. Pregnancy (OCPs prevent midcycle gonadotropin surge --> inhibit ovulation)

Induction of anesthesia

1. Propofol - lipophilic GABA agonist used for long term sedation. ADE-vasodilation-->hypotension, increase in TGs. 2. Etomidate - GABA agonist that is hemodynamically neutral (doesn't affect HR, BP, CO). But this can cause adrenocortical suppression. 3. Ketamine - NMDA antagonist that preserves respiratory drive. Provides analgesia. Stimulates release of catecholamines --> bronchodilation, increased HR, contractility...

Medications for weight loss

1. Sympathomimetics (phentermine, diethylpropion, benzphetamine) - increase NE release - stimulate/appetite suppressant. High rate of re-gain 2. Orlistat - intestinal lipase inhibitor 3. Bupropion/naltrexone - central appetite suppression (antidepressant+opioid antagonist)

Bacillus anthracis virulence

1. polypeptide capsule of *poly-gamma-D-glutamatic acid*: inhibits phagocytosis. 2. Trimeric exotoxin: protective antigen, edema factor, lethal factor. Protective antigen binds receptor and forms channel to deliver the toxins. *Lethal factor: zinc metalloproteinase that inhibits MAP kinase transduction --> death.* Edema factor: calmodulin-dependent adenylate cyclase --> increase cAMP --> fluid accumulates within/between cells and suppression of neutrophils and macrophages. (edema factor is similar to adenylate cyclase toxin of bordetella pertusis - also increases cAMP --> edema and phagocyte disruption).

How do Class 1 antiarrhythmics affect QRS and QT

1A: intermediate sodium channel activity --> prolong QRS. Moderate K+ blocking so significantly increase QT interval. 1B: No effect on QRS duration and don't prolong QT due to rapid dissociation. 1C: strong blockers that prolong QRS duration...this slightly prolongs QRS.

C diff pathophysiology and how to dx

2 toxins. Toxin A is enterotoxin and Toxin B is cytotoxin. A: recruits and activates neutrophils --> cytokines --> inflammation, fluid loss, diarrhea. B: induces actin depolymerization --> mucosal cell death, necrosis, pseudomembranes. These disrupt cytoskeleton and tight junctions --> pseudomembranes that are neutrophil predominant. Actin depolymerization. Dx: *NAAT - PCR to detect toxigenic strains.* - most sensitive. Enzyme immunoassay: antibody to detect c diff antigens or toxins. Rx: metronidazole, vanc, fidaxomicin

HIV infection course

2-4 weeks after inoculation: acute retroviral syndrome with mono-like symptoms and oropharyngeal ulcers and maculopapular rash. VERY HIGH veles of viral replication. +antigen but -antibodies.... = window period. Antibodies screening tests may be negative during this time. Develop antibodies after 6-8 weeks. Then viral load will decrease and the acute syndrome goes away. Usually remain asymptomatic until CD4+ drops and get opportunistic infections.

What is considered hypertonic saline and when is that used

3%. Severe symptomatic hyponatremia

treat meningitis

3rd gen cephalosporin (ceftriaxone works for h flu and n meningitidis) with vanco *** if listeria, give ampicillin

Finasteride

5-alpha reductase inhibitor. Inhibits T-->DHT. Use for BPH or male pattern baldness ADE: decreased libido, erectile dysfunction, decreased ejaculate volume. Residual testosterone is available for conversion by aromatase to estradiol --> gynecomastia.

Mycobacterium tuberculosis spondylitis

=Pott disease. Pt recently emigrated from Tb endemic region (nepal) now has progressive back pain, intermittent fever, vertebral bone destruction with an adjacent fluid collection (abscess). Usually months-years after primary pulmonary infection. Intermittent fever and slowly worsening pain in lumbar or lower thoracic spine. Infection frequently spreads behind the anterior ligament to adjacent vertebrae and intervertebral disc space --> contiguous bone destruction and abscess formation

What is *leuprolide* used for?

A GnRH analog. Used for prostate cancer...first acts as an agonist and causes tumor flare but then it acts as an antagonist by downregulating of GnRH receptor in the pituitary--> decreased FSH and LH. So it's also useful in cases where there is too many sex hormones. This is due to continuous stimulation. Another drug that does this is *Goserelin, buserelin.* Often give androgen receptor antagonist (*bicalutamide*) during first few weeks to block that initial rise in androgens. It inhibits endogenous GnRH release. Hypogonadotropic (FSH/LH) and hypogonadal (estrogen, testosterone) with continuous therapy.

How can H flu grow on blood agar

A gram negative coccobacilli.Requires X factor (hemantin) and V factor (NAD+) to grow. If you cross streak h flu on blood agar with s aureus, the h flu will grow around the staph because it actively secretes NAD+ into the medium. They also cause release of hemantin due to beta-hemolysis induced erythrocyte lysis. This is satellite phenomenon.

Panton-Valentine Leukocidin

A virulence factor that S. aureus can have, which allows the strain to cause *necrotizing pneumonia*; it forms pores in WBCs.

Treatment of hypertension in diabetics

ACEI or ARB. Decreases albumin excretion and slows progression to renal failure. To prevent progression of diabetic nephropathy, you want to have good glycemic control and blood pressure control. Specifically wouldn't want to use HCTZ as it causes hyperglycemia.

Prevent progression of kidney disease in a diabetic

ACEI or ARB. These lower the pressure in the glomerulus and reduce risk of chronic injury. If an ACEI is giving you a cough, switch to ARB...won't see that effect.

Donepezil

AChE inhibitor used for Alzheimer. Modest symptomatic improvement. Don't improve neuron survival. Memantine is a glutamate NMDA receptor antagonist. Prevents excitotoxicity and subsequent neuronal apoptosis. May serve a neuroprotective role to slow progression.

Pneumocystitis jiroveci

AIDS-defining illness. Often seen in patients previously unaware of HIV infection. Pulmonary symptoms, hypoxia, diffuse bilateral infiltrate. Diagnose with methenamine silver stain: crushed ping-pong balls or a circular ring around clear center. Treat with TMP-SMX.

Shigella pathogenesis and features

ALL species of Shigella are *invasive*. +They attach to and invade *M cells* in Peyer's patches. They induce *uptake/engulfment* into these cells. Inside the cells: *Lyse phagosome* & *replicate in cytoplasm*. Make actin filaments & *rocket/propel* onto *adjacent cells* to *evade immune-mediated clearance*. They *induce apoptosis.* Features:non-motile, non-lactose fermenting, does not produce H2S.

What would cause a hepatic abscess due to portal vein seeding

Abdominal infectious processes with enteric pathogens

Loop diuretic overuse. 18872.

Abused by patients with eating disorders. Increased urinary excretion of Na, Cl, K, and H+. --> metabolic alkalosis (elevated HCO3-). Overuse --> intravascular volume depletion --> activate RAAS. The secondary hyperaldosteronism --> increased Na+ reabsorption and lesser degree of passive Cl- reabsorption. Also increases K+ and H+ excretion in collecting duct --> hypokalemia and alkalosis. The alkalosis is further compounded by AT2 mediated increase in proximal tubule sodium bicarb reabsorption. Chloride depletion perpetuates alkalosis bc low Cl- is tubule lumen impaires HCO3- excretion. Within several hours (positive urine screen for drug): increased urine Na, Cl, K+. When the drug wears off, urine Na and Cl- are low as kidneys attempt to increase blood volume. Urine K+ will remain increased from aldosterone mediated loss. *Hypochloremic, hypokalemic metabolic alkalosis.*

Fibrates

Activate PPAR alpha, decrease VLDL synthesis. Upregulation LPL --> increased oxidation of fatty acids. Inhibit the rate-limiting step in bile acid synthesis, *7-a-hydroxylase*. So you have increased cholesterol excretion and decreased bile salt formation. Bile becomes supersaturated with cholesterol. So, reduced bile acid --> less cholesterol solubility so it promotes gallstone formation. Use with caution in preexisting gallbladder disease.

Vibrio cholerae

Activates adenylate cyclase via Gs ADP-ribosylation --> increases cAMP production in host cell --> secretory diarrhea, dehydration, electrolyte imbalance.

Chemotherapy induced nausea and vomiting

Acute phase: release of serotonin from intestinal enterochromaffin cells that have been damaged by chemo. Serotonin stimulates vagal afferent fibers that project to brainstem and stimulate vomiting reflex. *So serotonin receptor antagonists (ondansetron) can be used.* Also serotonin receptors in chemoreceptor trigger zone and solitary nucleus and tract. Delayed phase: 1-5 days. Increased substance P in brain from chemo-associated emetic stimuli in CSF and blood. Substance P binds NK-1 receptor in nucleus solitarius/area postrema --> vomiting. *so use NK-1 antagonists (aprepitant).* Area postrema in fourth ventricle has a chemoreceptor trigger zone that can respond to NTs, drugs, toxins. Nucleus tractus solitarius in medulla receives info from area postrema, GI tract via vagus nerve, vestibular system, and CNS. Neurons from NTS project to other medullary nuclei to coordinate vomiting.

What causes epididymitis? How does it present

Acute unilateral testicular pain, posterior testicle tenderness, pyuria. Organisms go from urethra --> ejac duct --> vas def. - Young men: chlamydia, gonorrhoea. May not have bacteriuria. - Old men (>35): less likely to have and STI. Usually due to E. Coli, often in setting of BPH. Will often have bacteriuria (Mumps cause orchitis - high dever and severe diffuse testicular pain, and also malaise, myalgia)

HSV encephalitis

Acute/subacute mental status change, seizures, headaches, neuro deficits. CSF: Hemorrhagic lymphocytic pleocytosis, increased protein, normal glucose. Bilateral temporal lobes on MRI. Treat with acyclovir... gets activated then competes with NTs for viral DNA polymerase...get synthesis termination

Treatment of gout

Acute: NSAIDs (first line), Colchicine (in patients with mild-moderate renal failure, peptic ulcer disease, or other NSAID contraindication). Colchicine can cause GI sx by disrupting microtubules in GI cells --> diarrhea, N/V. Colchicine disrupts the cytoskeleton dependent functions like chemotaxis and phagocytosis. Steroids if can't do colchicine or NSAIDs. Chronic: Probenecid: decrease proximal tubule uric acid reabsorption. Allopurinol: XO inhibitor. These are contraindicated in acute gout bc they mobilize tissue stores of UA and can worsen attacks. Both NSAIDs and colchicine basically inhibit neutrophils

Treatment of TB

Acute: Never a monotherapy --> antibiotic resistance quick. Get resistance to isoniazid via 2 mutations: decreased bacterial expression of catalase-peroxidase that activates isoniazid, and a mutation that modifies the protein binding site for isoniazid. Common regimen: isoniazid and rifampin + streptomycin, ethambutol, and/or pyrazinamide. Lasts a minimum of 6 months. If a patient has a positive PPD and negative CXR, then you can use the monotherapy.

Drugs that inhibit platelet plug formation (3)

Adhesion: Clopidogrel/ticlodipine: ADP inhibitor. and Aspirin: TXA2 inhibitor. Aggregation: Abciximab (Gp2b3a inhibitor).

ADE of prolonged glucocorticoid activity - adipose, adrenal cortex, bone, immune system, liver, skeletal muscle, skin

Adipose: lipolysis, altered fat distribution. Adrenal cortex: Atrophy Bone: osteoporosis Immune system: suppression, T-cell apoptosis Liver: Increased gluconeogenesis and glycogenolysis Skeletal muscle: atrophy (myopathy) (antagonize insulin) Skin: thinning, striae, impaired wound healing

Pseudomonas aeruginosa

Aerobic, gram-, catalase and oxidase +. Motile. Produces endotoxin (fever, shock) and exotoxin A (inhibits EF2), elastase (blood vessel destruction), phospholipase C (degrade cell membrane), pyocyanin (generate ROS). Causes: PNA (esp in CF and pts on vent), infections in *neutropenic*/burn patients, otitis externa, hot tub folliculitis, ecthyma gangrenosum (pictured - skin patches with necrosis and ulceration from insufficient blood flow). Treat: CAMPFIRE: carbapenems, aminoglycosides, monobactams, polymyxins, fluoroquinolones, thIRd/fourth gen cephalosporins (ceftazidime, cefepime), extended spectrum penicillins (piperacillin, ticarcillin)

Trypanosoma brucei

African sleeping sickness: large lymph nodes, recurring fever (antigenic variation), somnolence, coma Painful bite by tsetse fly. See trypomastigote in blood smear. Motile with single flagella. Suramin for blood disease; melarsoprol for CNS

Spironolactone

Aldosterone antagonist. K+ sparing diuretic. Blocks androgen receptor and decreases testosterone production --> gynecomastia, decreased libido. Eplerenone has fewer endocrine ADE.

Differ types of strep

All gram + cocci in chains. GAS (pyogenes) and GBS (agalactiae) are beta hemolytic but bacitracin resistance indicates GBS.

Differentiate the groups of strep

Alpha hemolytic (partial green hemolysis): Use optochin and bile. Optochin resistant and bile insoluble: strep viridans. Optochin sensitive and bile soluble: strep pneumo. Beta hemolytic strep: Bacitracin sensitive and PYR positive - GAS, bacitracin resistant and PYR negative and cAMP positive - GBS. Gamma hemolytic (no hemolysis) - if it grows in bile and 6.5% NaCl: Enterococci. If it grows in bile but not NaCl: strep gallolyticus

Serotonin Syndrome

Altered mental status Autonomic hyperactivity: hyperthermia, tachycardia, diaphoresis Neuromuscular excitation: hyperreflexia, clonus, tremor Treatment: cyproheptadine Drugs that increase 5-HT, psych drugs, non-psych drugs: tramadol, dextromethorphan, meperidine. ondansetron, triptan, st johns.

Treat opioid addiction

Alternative opioid agonists with fewer euphoric effects and less potential for acute withdrawal/craving. Use: methadone and buprenorphine. Methadone is a full mu agonist with a *long half-life*, which allows it to effectively suppress cravings and withdrawals ADE: QT prolongation, respiratory depression.

What drug that prolongs the QT interval has low risk of also causing Torsades de pointes

Amiodarone

Actinomyces. Shape, when do you see it, special findings, treatment

Anaerobic gram-positive bacilli with branching, filamentous growth. Can cause infection after mechanical trauma (tooth extraction). Grows without regard to tissue planes. Infections often in the cervicofacial region - a perimandibular mass. Often contain sulfur granule: yellow-orange granules in pus. Treat with penicillin. Pulmonary actinomycosis is usually caused by aspiration --> lower lobe consolidation and air bronchograms. Sulfur granules appear basophilic (purple/blue) on light microscopy with H and E.

HIV increases risk of these cancers

Anal and cervical squamous cell carcinoma (HPV) EBV lymphomas (and oral hairy leukoplakia)

-xaban reversal

Andexanet alfa. A biologic that shares homology with factor Xa but has no proteolytic effect. It's a decoy that binds Xa inhibitors. Reserved for life-threatening bleeds in patients on Xa inhibitor

Ranolazine

Anti-anginal drug. Inhibits late-phase inward sodium in ischemic heart cells during repolarization. So more calcium efflux and less myocardial O2 consumption

Benztropine

Anticholinergic, along with trihexyphenidyl. Used for parkinson to decrease muscarinic tone. Don't fix bradykinesia just tremor and rigidity. Also used for first gen antipsychotics extrapyramidal effects.c

Topiramate - MOA, use, ADE

Anticonvulsant. Blocks sodium and increases GABA action. Also use for migraine ppx. ADE:kidney stones, glaucoma, speech difficulty.

Preventive therapy for migraines

Anticonvulsants (topiramate, valproate), beta blockers, TCAs

Bupropion

Antidepressant with no sexual side effects or weight gain, can cause seizures (don't give if pt has eating disorder). Dopamine and NE reuptake inhibitor. (stimulant so useful for depression with hypersomnia and low energy). Nicotinic receptor antagonist.

Drugs commonly affected by drugs that affect CYP?

Antiepileptics Theophylline (adenosine antagonist; PDE inhibitor... bronchodilation by increasing cAMP. CYP inhibition --> Toxicity: excess CNS stimulation (tremor, insomnia, seizures), GI and cardiac issues (arrhythmias/tachycardia)) Warfarin

Neuroleptic malignant syndrome

Antipsychotics. Fever, encephalopathy, myoglobinuria, vitals unstable, increased enzymes (CK), muscle rigidity. Key: *fever, tachycardia, htn, ridity, increased CK* Treat: dantrolene, dopamine agonist (bromocriptine)

What are the second gen antipsychotics? What are their ADE

Aripiprazole, asen*apine*, cloz*apine*, olanz*apine*, queti*apine*, ilo*peridone*, pali*peridone*, ris*peridone*, luras*idone*, zipras*idone*. Metabolic syndrome...so monitor this. Highest risk are clozapine and olanzapine. Other ADE: agranulocytosis and seizures with clozapine. Risperidone causes hyperprolactinemia. Clozapine has seizure risk.

Treatment of asthma

As-needed short acting beta agonist (albuterol), inhaled corticosteroid (mometasone) Long acting beta agonist (salmeterol). If symptoms still uncontrolled - omalizumab: IgE-binding monoclonal antibody. Prevents IgE from binding to mast cells thereby inhibiting release of proinflammatory substances --> reduce airway inflammation.

For which fungal infection would you want to start with voriconazole?

Aspergillus

Aflatoxin

Aspergillus can produce this toxin. Causes p53 mutations. Associated with hepatocellular carcinoma.

Listeria

Asymptomatic to febrile gastroenteritis in healthy host. Invasive disease (sepsis, meningitis) in neonates, pregnant, elderly, immunocompromised In utero: chorioamnionitis, premature birth, fetal demise, neonatal sepsis/meningitis. Most severe neonatal infection: granulomatosis infantiseptica: multiple granulomas in internal organs.

Succinylcholine. MOA and ADE.

Attaches to nicotinic ACh receptor and depolarizes neuromuscular end plate. Not degraded by AChE --> continuous stimulation of end plate (initial transient fasciculations). Na+ channels become inactivated and can't reopen till repolarization. --> flaccid paralysis (phase 1 block). This channel is non-selective so it also allows K+ release --> hyperkalemia. This can cause arrhythmias in pts with myopathies, crush/burn injuries, denervating diseases/injuries. Can also cause malignant hyperthermia and brady or tachy cardia

Isoproterenol receptor binding and effects on SVR/CO

B1=B2 AGONIST. Decreases SVR and increases CO.

Dobutamine receptor binding and effects on SVR and CO

B1>B2 agonist. Decreases SVR and increases CO

Patient with acute febrile illness, thrombocytopenia, hemolytic anemia, abnormal liver function tests, intraerythrocytic inclusions (ring shaped and maltese cross forms)

Babesiosis: tick borne infection. See the parasites in RBC using giemsa. Maltese cross=tetrad of trophozoites. *Splenectomy increases risk.* Specifically carried by ixodes tick, which also carries borrelia burgdorferi. Coinfection is common Treat: atovaquone + azithromycin

Drugs for muscle spasticity

Baclofen (gaba agonist) Cyclobenzaprine Dantrolene (use for malignant hyperthermia and neuroleptic malignant syndrome Tizanidine (a2 agonist)

Treat COPD exacerbation

Beta adrenergic agonist. Relax bronchial smooth muscle by stimulating B2 (Gs --> increased cAMP)

Treat hyperthyroidism

Beta antagonists (propranolol) are indicated to alleviate the adrenergic symptoms (hyperthyroid has upregulate beta receptors) and then evaluation is done where you might administer methimazole to inhibit thyroid peroxidase (enzyme that iodinates tyrosine in colloid) - take a few weeks to be effective

What drugs improve survival in patients with heart failure due to LV systolic dysfunction?

Beta blockers (decrease work and oxygen demand - slows rate and contractility and decreases afterload by decreasing circulating levels of vasoconstrictors like renin), ACEI, Angiotensin 2 receptor blockers, aldosterone antagonists. The mortality benefit is due to decreased deleterious cardiac remodeling. AT2 and aldosterone --> cardiomyocyte hypertrophy and fibrosis. Beta blockers also reduce remodeling.

Treatment with what improves outcomes after an MI?

Beta blockers and ACEI

Drugs that increase insulin sensitivity

Biguanides (metformin), -glitazones

Gene enhancer

Bind activator proteins that facilitate bending of DNA. Increases rate of transcription. Can be upstream, downstream, or within introns. (silencers are similar but the decrease rate)

Glucocorticoids MOA

Bind cytoplasmic receptor, translocate to nucleus, and inhibit transcription of genes that encode inflammatory mediators and decrease immune cell survival and propagation....effects: 1. Decreased tissue production of proinflammatory PGs and LKAs thru inhibition of Phospholipase A2. 2. Decreased synthesis of almost all proinflammatory cytokines, with increased anti-inflammatory cytokines (IL-10). 3. Impaired macrophage activation and neutrophil emigration. 4. Increased apoptosis of eosinophils, T cells, monocytes, perhaps by decreasing Bcl-2 expression.

Staph toxic shock toxins

Bind invariant region of MHC-2 of APCs without first being processed. This then interacts with T cell receptor (beta chain) --> nonspecific stimulation of T cells. Same MOA for strep superantigen. Acquired via underlying mobile genetic element via bacteriophage or plasmid.

EBV

Binds CD21, the cellular receptor for C3d on B cells. EBV episome exists in nucleus of infected cells. This is the genome. Expresses latency genes: - periodic viral reactivation from memory B cells - promote survival of infected memory B cells Can cause nasopharyngeal cancer in Chinese people because they have nasopharyngeal epithelial premalignant lesions from their genetics and diet.

Vincristine/Vinblastine MOA and ADE

Binds beta-tubulin to inhibit microtubule formation. Neuropathy

Amphotericin toxicity and MOA

Binds ergosterol --> cell lysis. But it can bind human cholesterol and cause: - acute infusion reactions - dose-dependent *nephrotoxicity*: from decreased GFR. - significant electrolyte abnormalities (*hypomagnesemia and hypokalemia* --> arrhythmia) - anemia from suppression of renal EPO - thrombophlebitis at injection site

drug induced esophagitis is caused by? and what other ADE does this drug have? 14919

Bisphosphonates. Inhibit osteoclast-mediated bone resorption. Similar chemical structure of pyrophosphate and attach to hydroxyapatite on binding sites on bony surfaces to inhibit resorption. Esophagitis = burning pain in chest and dysphagia. These drugs are contraindicated in patients with impaired esophageal motility (sstricture, achalasia). Osteonecrosis of jaw

Fosfomycin MOA and resistance

Blocks development of NAM-NAG polymer backbone by inhibiting enzyme MurA. Resistance --> - efflux pumps - alterations to MurA that prevent fosfomycin binding

Lamotrigine MOA and ADE

Blocks voltage gated sodium channels. Used for partial and generalized seizure and effective for bipolar disorders. May will develop benign rash, but some will develop life threatening SJS-TEN. (SJS = <10%, TEN=>30%) Epidermal necrosis and subepidermal bullae.

Zidovudine ADE

Bone marrow toxicity --> anemia in 40% of patients

Lyme disease

Borrelia burgdorferi. Ixodes tick. Northeast USA. Spirochete. 1. Early localized: flu and erythema chornicum migrans (due to spread in dermis) 2. Early disseminated: facial palsy and/or cardiac involvement (AV block) 3. Late: in patients not given Abx. Asymmetric arthritis, subacute encephalopathy (decreased memory, mood changes, somnolence) Treat with doxycycline or penicillin-type abx: ceftriaxone. Reservoir=mouse;deer=essential to life but doesn't harbor.

Typhoid vs non typhoid salmonella

Both can cause gastroenteritis. Both penetrate enterocytes, travel in vacuoles to basolateral end of cell and invade lamina propria. Nontyphoidal: phagocytosed by neutrophils and macrophages in lamina propria --> massive inflammatory response by dramatic neutrophil infiltration. 1-5 of gastroenteritis. Typhoidal: contain *capsular antigen Vi that inhibits neutrophil recruitment/phagocytosis*. Limits acute inflammatory response and inhibits macrophages oxidative burst --> *unchecked intracellular replication* where it can then spread to RES. Results in typhoid fever. Typhoidal strains are fecal-oral. In areas with poor sanitation. Unvaccinated travelers are at risk of they don't adhere to food/water precautions. Escalating fever and *RELATIVE BRADYCARDIA*: pulse temperature association (high fever but pulse in the 60s). Patients develop abdominal pain, diarrhea, constipation, and transient salmon-colored macules (rose spots) on trunks. Can cause intestinal bleeding/perforation.

Salmonella typhi vs non typhi virulence immune response what it causes

Both have endotoxin; only typhi has capsule. Immune response: typhi-monocytes; non-typhi:PMNs. Typhi presentation: typhoid fever- rose spots on abdomen, constipation, abdominal pain, fever; later-GI ulcer and hemorrhage. Treated with ceftriaxone and fluoroquinolones. Stored in gallbladder. Non typhi doesn't need to be treated.

Heparin vs LMWH

Both have pentasaccharide to bind antithrombin 3 and induce conformational change that increases its ability to inactivate Factor Xa. Only heparin has a long enough pentasaccharide to inactivate thrombin too. LMWH: greater activity vs factor X1a. Heparin: equal against Xa and thrombin.

ketoconazole & spironolactone use

Both inhibit steroid synthesis: 17,20 desmolase and 17a-hydroxylase. Spironolactone also inhibits steroid binding. Used for PCOS gynecomastia and amenorrhea.

Rubella vs Measles

Both start on face and spread down. Rubella spreads faster and doesn't darken/coalesce. Rubella commonly has LAD

Treatment of bulimia and anorexia

Both: therapy and nutritional rehab. Can also add... Bulimia: SSRI Anorexia: Olanzapine (antipsychotic associated with weight gain)

Seizure treatment

Broad spectrum treat both focal and generalized (both hemispheres AT ONSET) (ex. juvenile myoclonic epilepsy) --> Levetiracetam, valproate. Narrow spectrum are used for focal onset (single hemisphere) only --> Carbamazepine, phenytoin (levitiracetam and lamotrigine too) Absence: Ethosuximide, valproic acid

Infant with worsening cough and respiratory distress with diffuse wheezing and crackles

Bronchiolitis: LRTI. Most commonly caused by RSV. Bordetella has a whooping cough and clear lungs. *RSV Bronchiolitis: URT sx followed by WHEEZING, cough, and respiratory distress* RSV uses fusion protein for entry.

Acute febrile illness with tender, erythematous inguinal LAD

Bubonic plague: zoonotic infection endemic to SW US. Yersinia pestis: gram-negetive coccovacillus with bipolar staining on Giemsa or Wright. Rodents are primariy reservoir. Tranmission via rodent flea bite.

EBV cancers

Burkitt Lymphoma (NHL) (esp endemic african type) Hodgkin Lymphoma and Nasopharyngeal carcinoma CNS lymphoma in HIV Post transplant lymphoproliferative disorder in allograft recipients. In patients with HIV, there is a very high risk of EBV associated lymphomafmyoc

How does cocaine work

By inhibiting NE re-uptake

GI sx with bowel wall bx showing acute inflammation, epithelial necrosis, denuded epithelium, fibrin, inflammatory cells

C diff pseudomembrane. May cause toxic megacolon leading to colonic perforation

Intranuclear and intracytoplasmic inclusions

CMV. "owls eyes"

Entacapone MOA

COMT inhibitor: prevents peripheral L-DOPA degradation. Combine it with levdopa to increase levdopa half life.

Decrease breakdown of levodopa in peripheral tissue

COMT inhibitors: entacapone, tolcapone dopa decarboxylase inhibitors: carbidopa

Effects of androgen abuse CV, derm, GU, psych, breast, other, muscles

CV: increased Hematocrit, increased LDL. Derm: Acne, hirsutism, male-pattern hair loss. GU: clitoromegaly, oligomenorrhea, testicular atrophy, decreased spermatogenesis. Psych: women-depression, hypomania. men-aggressiveness, mood disorders. Breast: women-atrophy. men-gynecomastia Other: deepening of voice, premature epiphyseal closure in adolescents Increased muscle mass

Pt camping in new mexico. Now has fever, muscle pain, diffuse and painful swelling of neck, underarms, groin area. physical exam shows generalized scattered black maculae. Upper extremity shows erythematous, solid, tender mass on underside of upper extremity just above elbow. Mass is draining blood and necrotic material. What is it and how to treat?

Camping trip in New Mexico (SW USA) -> zoonotic infection! I thought it was Francisella (bc lymphadenopathy, necrotic ulcers) which would be treated with Streptomycin (aminoglycoside which would inhibit 30S ribosomal subunit). But I looked up other explanations and the other possibility is this is Yersinia pestis (Bubonic plague) which presents similarly. Apparently Francisella is more seen in the Midwest while Yersina pestis is more common in SW USA (like New Mexico). Both Yersina pestis & Francisella are tx with aminoglycosides though so the answer choice would be the same

Opioid withdrawl

Can be 6-12 hours after cessation of short acting (heroin) and usually peaks within 24-48 hours. N/V, diarrhea, creamps, myalgia. Dilated pupils, *hyperactive bowel*, *lacrimation and yawning, piloerection.* Anxiety. Not lifethreatning (alcohol/benzo withdrawal is)

Ascaris lumbricoides

Can be from ingesting soil. May actually see the worm come out of butt. Ball of worms causes obstruction at ileocecal valve, biliary obstruction, intestinal perforation, migrates from nose/mouth. Knobby-coated, oval eggs in feces. Treat with bendazole

Regular insulin

Can be given IV or subQ. No AA modifications. When given SubQ, it polymerizes into hexamers which delays absorption. Starts working within 30 mins, peaks in 2-4 hours, and lasts 5-8 hours.

Amantadine

Can be used for parkinson - direct and indirect dopaminergic agent. Alleviates some of the motor symptoms of PD by enhancing the effects of endogenous dopamine. Also some anticholinergic effects.

Why do loop diuretics cause metabolic alkalosis?

Can reabsorb solutes --> lose water --> volume contraction --> activation of RAAS --> increased renal tubule bicarb reabsorption. Also hypokalemia.

Esophagitis in HIV patients

Candida can cause exudative esophagitis with concurrent oral thrush. Can have *pseudomembranes.* CMV can cause *linear* ulcerative esophagitis in distal esophagus. HSV-1: small vesicles --> "punched out" ulcers All can manifest as dysphagia (difficulty swallowing) and/or odynophagia (pain on swallowing)

DOC for extended spectrum beta lactamase producing organisms?

Carbapenems

Metoprolol

Cardioselective Beta-Blocker. No change in svr but facilitates mild reduction in bp due to decrease in contractility and heart rate that reduces stroke volume and cardiac output.

Treatment of acute MI (in pt with COPD). 1196

Cardioselective beta blockers with predominant b1 action are safe in pts with COPD. Combined beta and alpha are also safe. Cardioselective: Atenolol, bisoprolol, nebivolol, metoprolol Alpha and beta block: carved*ilol*, labet*alol* If you use a non-cardioselective beta blocker (propranolol, nadolol, timolol, pindolol), the b2 blockade can trigger bronchospasm.

Treatment of gonorrhea, chlamydia

Ceftriaxone (3rd gen cephalosporin) + azithromycin (macrolide).... (the azithromycin protects against chlamydia co-infection).Would only use azithromycin for chlamydia. Can also use doxycycline for chlamydia. Just remember...chlamydia lacks classic cell wall (muramic acid) so beta lactams not effective.

Selective COX-2 inhibitors

Celecoxib. Anti-inflammatory with no effect on platelet function. Lower risk of GI bleeds but increased risk of thrombosis.

Paracoccidioides brasiliensis

Central and south america. Mucocutaneous: chronic mucocutaneous or cutaneous ulcers, can progress to lymph nodes and lungs. DIMORPHIC! Culture (25˚C): multiple blastoconidia Bx: cells covered in budding blastoconidia

NMDA antagonist post cerebral infarcy

Cerebral infarction --> presynaptic glutamate release --> binds NMDA --> high sodium and calcium enter cell --> excitotoxicity. NMDA antagonists can protect against. Too much calcium can activate apoptotic phospholipases

When is clindamycin used

Certain infections caused by oxacillin-resistant Staph.

Malaria treatment/ppx of P falciparum

Chemoprophylaxis while in Africa and for 4 weeks after return. For ppx: in africa, chloroquine resistant p. falciparum is endemic so use atovaquone-proguanil, doxycycline, mefloquine. Mefloquine is a schizonitide that actively destroys replicating parasites in RBCs. But it's inactivated in liver and has no efficacy against hepatic schizonts. So you use ppx for 4 weeks upon return to ensure that anything released from the liver will be destroyed when it infects RBCs. P falciparum does not have a dormant hepatic phase; it matures in (and is release from) liver over 8-30 days (as opposed to vivax and ovale)

Person with recent travel history. Had a febrile illness and rash. Now has severe polyarthritis. 14903.

Chikungunya fever. Alpha virus. Arbovirus. Literally means "stooped walk" because of severe joint symptoms. *high fever, symmetric polyarticular arthralgia, maculopapular rash.* Lymphopenia and thrombocytopenia common. May develop into relapsed or chronic arthralgias, polyarthritis (wrist, finger ankle), and tenosynovitis.

Outcome of most Hep C infections without treatmen.

Chronic infections

TB meningitis

Circulating bacili lodge in subependymal or subpial space --> tubercle that subsequently ruptures into subarachnoid space: - thick, gelatinous exudate in basal portion of brain - vasculitis of cerebral arteries --> multiple bilateral brain infarcts - hydrocephalus (obstruction of CSF outflow by tubercular proteins) --> increased ICP and ventriculomegaly

What drugs affect QRS duration?

Class 1C (maybe all class 1s?? - yeah i think all class 1s but 1C the most) But definitely not classes 2,3,4.

Which antiarrhythmic causes QRS prolongation without muct QT prolongation

Class 1C. QT interval represents ventricular depolarization and repolarization. QRS only contributes a little so QT interval is primarily a measure of ventricular repolarization.

Amiodarone MOA and ADE

Class 3 antiarrhythmic. Can be used for management of ventricular arrhythmia in acute MI. Negative chronotropy. ADE: photodermatitis, blue/gray skin discoloration, pulmonary fibrosis, liver toxicity, hypo/hyper thyroidism.

alpha 2 agonists

Clonidine, Methyldopa

Which drugs inhibit ADP mediated platelet aggregation

Clopidogrel, ticlopidine

Management of treatment resistant schizophrenia (ex. have failed at least 2 antipsychotics)

Clozapine: superior efficacy in treatment resistant schizophrenia. Monitor neutrophil count....risk of agranulocytosis. Also risk of weight gain and metabolic effects

What kind of fungus is in SW US? What kind of infection does it cause? How does it stain?

Coccidioidomycosis. Pulmonary infection with occasional dissemination to skin/bone. Will see a spherule full of endospores, DIMORPHIC!! Culture (25˚C): hyphae Biopsy: thick walled spherules in endospore.

Opioid mu receptor agonists. Presentation of intoxication?

Codeine, fentanyl, hydromorphone, meperidine, methadone, oxymorphone... Decreased respiratory rate (improves with naloxone), depressed mental status, miosis, decreased bowel signs, hypotension (opioid induced histamine release).

Cholera

Comma shaped, oxidase positive, highly motile, gram negative rod. Contaminated food/water. Severe, watery diarrhea. Very acid sensitive, so you need a high burden to cause symptoms. But if you have decreased gastric acid (ex. on PPI), you're more susceptible.

H pylori

Common cause of peptic ulcers. Diagnose with rapid urease test. Urease: splits gastric urea into ammonia and CO2. Ammonia --> increase local pH to allow bacteria to survive (phenol red will turn from yellow to pink if alkaline) Located in the antrum. Commonly causes ulcers in duodenum. Risk for peptic ulcer disease, gastric adenocarcinoma, MALT Lymphoma

Sciatic Neuropathy

Common complication of hip fracture (femoral head) and/or arthroplasty because of proximity. Injury --> neurologic deficits across sciatic nerve: sciatic nerve: knee flexion common peroneal nerve: dorsiflexion, sensory numbness tibial nerve: plantar flexion, ankle reflex

Mycoplasma pneumoniae (what is causes, pathogenesis, treatment)

Common in adolescents with walking pneumonia (insidious onset, headache, non-productive cough, patchy/diffuse infiltrates - cxr looks way worse than pt). Attaches to resp epithelium with surface antigens (I-antigens) that are also on RBC plasma membranes. So, patients typically develop *cross-reactive* IgM antibodies that can attach to RBC --> complement --> lysis. These are *COLD agglutinins*. Attach at cold temperature. May cause a mild hemolytic anemia. Culture: requires *cholesterol supplementation* to grow on artificial media. Treatment: macrolide, doxycycline, fluoroquinolone

Viral vs bacterial meningitis

Common microbes: Viral: *enterovirus*, arbovirus, HSV2 Bacterial: adult -s pneumo and n meningitides. neonate - GBS, GNR. CSF: Viral: WBC<500, lymphocyte predominant, low-normal glucose, protein <150, no organisms on gram stain/culture. Bacterial: WBC>1000, neutrophil predominant, glucose < 45, protein >250, gram stain often positive. Viral is usually less sever.

Eculizumab

Complement protein C5. used for Paroxysmal nocturnal hemoglobinuria. Would need penicillin ppx for neisseria meningitidis risk

Nausea treatment

Conditions that cause GI irritation (infection, chemo, distension) --> increase mucosal serotonin. So use 5-HT3 antagonists (ondansetron). Also: dopamine antagonists (prochlorperazine, metoclopramide) and NK-1 antagonists (-aprepitant). Vestibular nausea (motion sickness): first gen H1 antagonists, Ach antagonist scopolamine, promethazine (dopamine and H1 antagonist)

Crescent shaped organism that causes *continental hydrocephalus, chorioretinitis, intracranial calcifications*

Congenital toxoplasmosis. Calcifications are diffuse. Acquired via vat feces or consumption of undercooked meat. Triad: chorioretinitis, hydrocephalus, diffuse intracranial calcifications.

Marihuana intoxication

Conjunctival infection, tachycardia, increased appetite, dry mouth.

Campylobacter

Contaminated food and pets. *Motile, curved, gram negative rod. Oxidase positive.*

mtb virulence

Cord factor: activates macrophages (promotes granuloma formation) and induces release of TNF alpha Sulfatides (surface glycolipids) inhibit phagolysosome fusion

Dextromethorphan

Cough suppressant. Inhibits medullary cough center thru sigma receptor activation. Structurally very similar to other opioids but has minimal mu and delta affinity. So at therapeutic doses, there are very little opioid ADE. However, it increases serotonin activity in CNS by decreasing rate of serotonin reuptake and directly stimulating serotonin receptors. So, abuse can cause serotonin syndrome: hypertonia, spasticity, autonomic instability, encephalopathy. Often occurs in overdose or accidental drug interaction with other serotonergic drugs. Addiction not likely.

Q fever

Coxiella burnetii. Spores inhaled from cattle/sheep amniotic fluid. Unpaserutized milk. *No arthropod vector.* Headache, cough, flu-like sx, *PNA*. May have *hepatitis*. Culture - endocarditis. Usually no rash.

Culture negative endocarditis

Coxiella burnetti or Bartonella

Herpangina

Coxsackie A virus = hand, foot, mouth disease Ssx: multiple small ulcers/vesicles on posterior pharynx and on fingers + FVR, dysphagia RF: fecal-oral transmission from swimming pools / water parks self-limiting. no complications

What are the enteroviruses that cause meningitis

Coxsackie, echovirus, poliovirus

Cyclophosphamide MOA and ADE

Cross link DNA to inhibit DNA synthesis. Hemorrhagic cystitis, bladder cancer.

Cisplatin MOA and ADE

Cross link DNA to inhibit DNA synthesis. Nephrotoxicity, ototoxicity, peripheral neuropathy

Yeast with a thick capsule

Cryptococcus (doesn't absorb india ink). Causes meningitis in immunocompromised. Latex agglutination positive. Morphology - round/oval with narrow-based buds (budding yeast). Lives in soil contaminated by bird droppings. Inhaled into lungs --> lymph nodes --> activate CD4+ --> granuloma. Most people develop life-long latent infection. Meningitis occurs when it gets into blood and spreads to brain. CSF: low glucose, increased protein, mild pleocytosis (esp in HIV patients)with predominance of lymphocytes. May present with headache, fever, lethargy over 2 weeks. Symptoms more acute/severe in HIV patients. Treatment: initial: amphotericin B and flucytosine. Long term: fluconazole

Person has a skin lesion and bx shows intracellular protozoa with rod-shaped kinetoplasts

Cutaneous leishmaniasis. Middle east/central and south america. Infected sand flies. Intracellular, round-oval amastigotes with rod-shaped kinetoplasts Cutaneous: chronic, enlarging, pinkish papule at bite site.

Nitroprusside toxicity

Cyanide toxicity. Nitroprusside is a vasodilator. It's metabolized into NO and cyanide. Cyanide is a potent mitochondrial toxin that binds Fe3+ in cyt C oxidase --> inhibits ETC and halts aerobic respiration. Toxicity: Altered mental status, seizures, cardiovascular collapse, lactic acidosis, bright red blood. Cyanide is normally metabolized by rhodanese, an enzyme that transfers a sulfur to cyanide to form thiocyanate --> excreted in urine. Cyanide OD: deplete available sulfur. Treat: *sodium thiosulfate* (sulfur donor to promote hepatic rhoadene-mediated conversion of cyanide to thiocyanate): Also hydroxocobalamin (directly binds cyanide) and sodium nitrite (induces methemoglobinemia).

Calcineurin inhibitors

Cyclosporine Tacrolimus Immunosuppressants.

Fludarabine

Cytotoxic purine analog used for CLL

treatment of rheumatoid arthritis

DMARDs for pain and inflammation and reduce long term joint destruction: methotrexate, sulfasalazine, hydroxychloroquine, minocycline, TNF-alpha inhibitors. These take weeks to work. Short term: NSAIDs and steroids. (not helpful in long term)

Direct thrombin inhibitor

Dabigatran . Also argatroban and bivalirudin. Dabigatran is used for a fib or venous thromboembolism. This inhibit activated thrombin - so directly inhibit conversion of fibrinogen to fibrin.

Treatment of PCOS

Decrease androgen levels (hirsutism or acne), decrease estrogen levels (anovulation). Decrease estrogen with aromatase inhibitor to decrease estrogen production - this normalizes LH and FSH release and allows for ovulation to occur To treat hirsutism: OCPs. Suppress LH secretion --> decrease ovarian androgen production. And increase sex hormone binding globulin --> less free T

-gliflozin

Decrease glucose reabsorption in PCT. SGLT-2 inhibitors. More sodium will be delivered to the macula densa so there will be a decrease in renin --> lower glomerular pressures and reduced hyperfiltration

Which HIV drugs inhibit reverse transcriptase but are not nucleotide analogs

Delavirdine, efavirenz, nevirapine. These are NNRTIs.

When do you use Griseofulvin or Terbinafine

Dermatophytes. Terbinafine specifically accumulates in skin, nails, adipose tissue (onychomycosis).

Potency of anesthetic

Determined by minimum concentration in brain necessary to achieve adequate level of anesthesia. Minimum alveolar concentration = percentage of anesthetic in inspired gas mixture that renders 50% of patients unresponsive to pain. Corresponds to ED50 of dose-effect curve. Potency is inversely proportional to the MAC. Higher lipid solubility = more potent. Lower MAC = more potent.

Lithium ADE

Diabetes insipidus Hypothyroidism Tremor Ebstein anomaly (teratogenic)

Cox1 and Cox2 inhibitors

Diclofenac, ibuprofen, indomethacin. Reversible

What should you be thinking for cat, dog bites.

Dog: Pasteurella. Infection within 24 hours and mouse like odor. Cat: Pasteurella (most common). And bartonella henselae (lymphangitis in immunocompetent hosts; use silver stain; large endothelial cells forming vascular channels around inflammatory infiltrate)

Metoclopramide issues and how to prevent

Dopamine ]blockage in basal ganglia --> excess cholinergic --> extrapyramidal symptoms --> acute dystonic reactions. Give diphenhydramine with the blockers (metoclopramide or prochlorperazine) to reduce the anticholinergic activity

Drug induced gynecomastia

Drugs that increase estrogen:testosterone ratio. Estrogen Antiandrogens (flutamide, bicalutamide) 5-alpha reductase inhibitors (finasteride) Spironolactone Ketoconazole (decrease synthesis of steroid hormones) Cimetidine (inhibits testosterone receptor) Androgen-anabolic steroids (aromatization to estrogen)

What can trigger statin myopathy? How to prevent?

Drugs that inhibit CYP!! (macrolides (but not azithromycin), ketoconazole, non-dihydropyridine CCBs, amiodarone, ritonavir) OATP inhibitor: cyclosporine Additive myocyte toxicity: steroids, fibrates, colchicine Pravastatin is NOT metabolized by CYP so if patients need to take a CYP inhibitor, consider switching to that.

Anesthesia induction....what properties are relevant?

During induction with a gaseous agent, the partial pressure of anesthesia rises until it reaches its partial pressure in the inspired gas. At that point, no more can dissolve in blood and blood is saturated. The speed at which the blood becomes saturated depends on the solubility of the gas in blood. Highly soluble --> dissolve easily --> larger amounts must be absorbed for the blood to be saturated. Blood solubility is indicated by blood/gas partition coefficient: high blood solubility, high coefficient. N2O is poorly soluble so it has a low coefficient - fast induction. Speed of induction is determined by rate at which brain tissue takes up agent, which depends on blood solubility. *If it has poor blood solubility, the amount of gas needed to saturate the blood is small and brain saturation occurs quickly.* Highly soluble are absorbed greater--> delayed CNS saturation. So: a poorly soluble gas like N2O will: -small amount needed to saturate blood - rapid rise in blood partial pressure -rapid equilibration with brain - rapid onset of action Whereas a highly soluble gas like halothane: -large amount needed to saturate blood -slow rise in partial pressure in blood -slow equilibration with brain -slow onset of action

Indole positive

E. Coli. This would differ it from enterobacter cloacae, another lactose fermenting GNR that commonly causes UTI in females...

EHEC... and compare this to other E. Coli

EHEC O157: H7 --> hemorrhagic colitis often after hamburger meat. This strain does NOT ferment sorbitol on MacConkey and also unlike other strains, it does NOT produce glucuronidase. Produces shiga-like toxin that inactivate 60s ribosomal subunit. Does NOT invade. Risk of hemolytic uremic syndrome: thrombocytopenia, MAHA, renal insufficiency. EIEC invades, ETEC (travelers diarrhea) produces heat labile (increase cAMP) (cholera-like toxin) and heat stable (increase cGMP) toxins --> increased absorption and increased secretion.

Typhus

Endemic-fleas-rickettsia typhi epidemic-louse-prowazekii; central rash that spread out but spares palms/soles.

What binds toll like receptors?

Endotoxin of gram negative bacteria. --> rapid onset fever/hypotension

HIV fusion inhibitor

Enfuvirtide. Binds Gp41 and prevents it from approximating the host and viral membranes

Treatment of thromboembolic disease (pt with a DVT)

Enoxaparin: low molecular weight heparin. Doesn't cross placenta. Relatively long half life... Use unfractionated heparin at term in pregnant women as it can be discontinued at onset of labor to minimize hemorrhagic risk (short half life).

UTI that doesn't convert nitrates to nitrites

Enterococcus

Tetanus toxin

Enters presynaptic terminals of LMN and travels retrograde to CNS. In spinal cord anterior horn cells, it blocks inhibitory interneurons --> spasmodic muscle contractions.

Dopamine agonists

Ergot—Bromocriptine Non-ergot (preferred)—pramipexole, ropinirole Can delay the need to start levodopa in parkinson. Bromocriptine can also treat hyperprolactinemia.

Which induction drug causes adrenocortical suppression

Etomidate. Avoid in patients with septic shock.

Before starting TNF-alpha inhibitor, you should

Evaluate pt for latent tuberculosis. TNF alpha impairs cell-mediated immunity.

What causes lung abscesses in alcoholics

Facultative and strict anaerobic oral organisms: bacteroides, prevotella, fusobacterium, peptostrep. Often polymicrobial. Subacute fever, foul-smelling sputum, weight loss, night sweats, digital clubbing. Dense fluid collection with air-fluid level in dependent parts of lung. Treat with ampicillin or carbapenem for coverage of oral anaerobes and aerobic gram positives. clindamycin only with penicillin allergies due to C diff risk.

Malaria presentation and lifecycle

Fever, chills, sweats, RBC inclusions on Giemsa following travel to geographic region (South america, africa, india, asia). Fever and sweating that occur every 48 hours. Inoculation --> travel to liver and replicate. Lysis of hepatocytes --> release merozoites that infect RBCs. RBC lysis causes the relapsing fever/ sweating. Vivax and Ovale establish latent infection in liver in form of hypnozoites - responsible for relapses. Primaquine must be used to eradicate hypnozoites (avoid in G6PD deficiency).

Neonatal meningitis causes and presentation

Fever, irritability, poor feeding. CSF with leukocytes. group b strep, E coli, listeria monocytogenes. Treat with ampicillin and gentamicin. COmplications: long term neuro deficits: delay and seizures older infants and adults: strep pneumo and n meningitidis

Treat a STEMI

Fibrinolytic agents (alteplase, tenecteplase, steptokinase) if they can't get percutaneous coronary intervention fast. Activates plasmin to break down the clot. May result in self-limiting reperfusion-related arrhythmia. HAVE TO USE SOMETHING TO BREAK DOWN THE CLOT - NOT JUST PREVENT AN ANTICOAGULANT. Heparin may be used to prevent further progression of a clot but it doesn't cause thrombolysis.

Macrocyclic antibiotic that inhibits sigma of RNA polymerase

Fidaxomicin. Used for C diff.

Alcohol withdrawl

First 24 hours: tremors, insomnia, palpitations. 12-24 hours: seizures, hallucinations. 48-96 hours: Delirium tremens - confusion, agitation, fever, tachycardia, HTN, diaphoresis, hallucinations Alcohol withdrawal leads to sympathetic overdrive.

First and second order kinetics

First order: rate of drug metabolism changes with increasing drug doses. Quantity of drug metabolism is directly proportional to dose administered: fixed proportion. At high drug doses, metabolism can't continue and change to zero order kinetics: constant amount of drug metabolized per unit time regardless of concentration/dose.

NNRTIs ADE

Flu-like, abdominal pain, jaundice = life threatening hepatic failure and SJS-TEN.

Treat low HDL and reduce risk of CV events

Focus on lowering LDL with statins. Niacin would increase HDL but it doesn't lower CV risk. Almost all lipid lowering drugs increase HDL but statins have the benefit of reducing CV risk.

Methotrexate. 1892. 1857. MOA and ADE.

Folic acid analog that inhibits DHFR (reduces folic acid to tetrahydrofolate). THF participates in transfer of carbon groups in purine and thymidine synthesis. Leucovorin (folinic acid) is N5-formyl-tetrahydrofolate that doesn't need to be reduced by DHFR to be a cofactor so it is used to rescue normal cells from MTX. Build up of folic acid and dihydrofolate polyglutamate. Death of rapidly dividing cells - Ex. GI mucosa - aphthous ulcers in the mouth Bone marrow - Pancytopenia Hair follicles - alopecia Also: Hepatotoxicity (hepatitis, fibrosis, cirrhosis) and pulmonary fibrosis.

Aspergillus

Fungal hyphae branching at acute angles with septations. Only exists as *mold*: multicellular hyphae. Causes: 1. invasive aspergillosis in immunosuppressed patients (ex. treatment for leukemia/lymphoma). Granulomas in lung/lung infection. hematogenous spread to skin, paranasal sinus, kidney, endocardium, brain. 2. Aspergillomas - fungal balls in lung cavities. 3. Allergic bronchopulmonary aspergillosis - in asthmatics...presents with wheezing, migrating pulmonary infiltrates, increased IgE.

What drugs increase glucose-dependent insulin release

GLP-1 is the peptide that does. So DPP-4 inhibitors (-gliptin) and GLP-1 agonists (exenatide, liraglutide). These have low risk of hypoglycemia since they're glucose dependent.

Treat prostate adenocarcinoma

Generally androgen sensitive. Initial treatment: medical/surgical orchiectomy to eliminate testicular production of androgens. But, androgens are also made in adrenal glands and tumor cells via 17-alpha-hydroxylase (CYP) that converts pregnenolone/progesterone to DHEA/androstenedione. *Drug: Abiraterone: irreversibly inhibits 17-alpha hydroxylase*

Nicotine withdrawl

Generally mild. Dysphoria, irritability, anxiety, increased appetite.

Why are HCV antibodies not enough to clear infection?

Genetic variations with a marked variety in antigenic structure of HCV envelope proteins

HSV-1 infection

Gingivostomatitis, fever, esophagitis, keratoconjunctivitis, cold sores, temporal lobe encephalitis. Neonatal form can cause fever/seizures.

Ovulation induction

Give Menotropin that mimics FSH and triggers formation of dominant ovarian follicle. When the follicle appears mature, give hCG. This is structurally similar to LH and stimulates the LH surge by induce ovulation.

Giving renally cleared drugs to elderly

Given them lower doses. Old people may have a normal creatinine BUT - creatinine is derived from muscle which old people have less of.

Drugs that affect calcium/bones (all these are associated with fractures)

Glucocorticoids: decrease bone formation PPI: decrease Ca absorption Anticonvulsants that induce cyp: increase Vit D catabolism And drugs that decrease estrogen

HIV attachment

Gp120 binds CD4 and CCR5 (or CXCR4). Then that induces a gp120 conf change and expose the underlying transmembrane gp41 --> viral fusion

Yersinia enterocolitica

Gram - coccobacillus with bipolar staining. Usually transmitted from pet feces (e.g., puppies), contaminated milk, or pork. Outbreaks are common in day-care centers. Blood diarrhea. Sx can mimic Crohn's or appendicitis: RLQ pain from mesenteric adenitis and/or terminal ileitis. Reactive arthritis.

Brucella

Gram -ve. coccobacillus. Animals or unpasteurized milk. Lives in macs in RES. Non caseating granulomas. Undulant fever, night sweats, arthralgias. Treat: doxycycline + rifampin or streptomycin

H flu

Gram negative coccobacillus. Nontypeable strains: otitis media, conjunctivitis, bronchitis. Also causes meningitis, PNA, epiglottitis. Virulence: polysaccharide capsule made of polymer *polyribosylribitol phosphate phosphate (PRP).* Protects against phagocytosis and complement mediated lysis by binding factor H: prevents C3b deposition. Also produces *IgA protease.* Vaccine is conjugated to protein toxoid. Treat with amoxicillin for mucosal infections; ceftriaxone for meningitis; rifampin ppx for close contacts.

Bordetella pertusis

Gram negative coccobacillus. Droplets.. Infants/children: mucoid rhinorrhea followed by paroxysmal *cough*, often *but not always!) with inspiratory whoop and subsequent *vomiting*. Tracheal cytotoxin --> directly damages and destroys ciliated epithelial cells (-->cough) Pertussis toxin --> disinhibit adenylate cyclase via Gi ADP-ribosylation --> increased cAMP --> increases histamine sensitivity (edema) and phagocyte dysfunction. And adenylate cyclase toxin --> increases cAMP --> inhibit phagocyte activity and cause lymphocytosis

Who has endotoxins/lipopolysaccharides

Gram negative pathogens. Gram+ don't have endotoxins.

C perfringens

Gram positive bacillus. Gas gangrene. Anaerobic. Produce phospholipase toxin that attacks cell membrane --> necrosis. Also causes food poisoning when ingesting spores.

Nocardia

Gram positive rod - beaded or branching Partially acid fast; aerobic. Endemic in soil; contracted via inhalation or skin puncture Immunocompromised or elderly patients Clinical features: PNA similar to tb, brain abscesses, cutaneous involvement. Treatment: TMP-SMX and surgical drainage

Listeria monocytogenes - stain, special features, who it affects

Gram positive rod with tumbling motility. Multiplies in the cold so its food borne. Narrow zone of beta hemolysis. Facultative intracellular. Often affects immunocompromised and pregnant women. Listeriolysin O: pores in phagosomes Actin-based transcellular spread (doesn't re-enter the extracellular space). Therefore, infection is primarily controlled by CD8+ cells.

Clostridium perfringens

Gram positive rod. Spore induction in penetrating injury. Gas gangrene (uses carbs for metabolism) Alpha toxin --> phospholipase C mimetic --> splits host phospholipids --> cell lysis and tissue necrosis. Also: intravascular aggregations of PLTs, neutrophils, fibrin --> vascular occlusion and anaerobic environment.

Dipthera

Gram positive rods in angular arrangements. Dissemination: myocarditis, arrhythmia, neuropathy + elek test for toxin gram + rods (club shaped) with metachromatic granules on loffler media black colonies on cystine-tellurite

Cutaneous Leishmaniasis

Granulomatous inflammation and intracellular amastigotes in macrophages. May present with ulcerated papules and nodules. Middle east, central, south america. Sandfly transmission. Treat with amphotericin, sodium stibogluconate

Antifungal targets: Griseofulvin, flucytosine, caspofungin, amphotericin, nystatin, azoles, terbinafine

Griseofulvin: mitosis; binds microtubules. Flucytosine: DNA/RNA synthesis.Inhibits protein synthesis by replacing uracil with 5-FU in mRNA Caspofungin (echinocandin): Cell wall - blocks synthesis of 1,3-beta-D glucan. Amphotericin B and Nystatin bind ergosterol -Azoles: inhibit ergosterol synthesis by inhibiting the CYP that converts lanosterol to ergosterol. Terbinafine: inhibit squalene epoxidase (ergosterol synthesis)

Chancroid

H. ducreyi. Deep, purulent, painful ulcers with matted/suppurative lymphadenitis. Dx with gram stain/culture and PCR - Gram negative rods in "school of fish" chain

Thiazide diuretics

HCTZ, chlorthalidone, metolazone

Roseola infantum

HHV-6. High fevers for several days --> seizures followed by diffuse macular wash that starts on trunk and spreads to extremities. Babies less than 2.

Maraviroc

HIV drug: CCR5 (macrophage) inhibitor. So it blocks interaction with gp120

HIV patient with progressive cognitive decline

HIV-associated dementia. AKA HIV encephalopathy Develop features of subcortical dementia --> working memory deficits, executive dysfunction, slow info processing. HIV enters CNS via infected *monocytes*. Establishes infection in microglial cells (resident *macrophages* of CNS) and blood-derived perivascular macrophages. Infection of these cells and inflammation causes them to closter into small areas of necrosis, *forming microglial nodules, and fusion to form multinucleated giant cells*. HIV does not invade the neurons...the dementia is due to release of neurotoxic compounds by activated monocytes.

Statins

HMG-CoA structural analogs --> competitively inhibit HMG-CoA reductase. Inhibit conversion of *HMG-CoA to mevalonate.* Increase in LDL receptor recycling. ADE: myopathy (can have myonecrosis leading to elevated CK, or rhabodymyolysis), hepatitis (check LFTs before starting)

Condyloma acuminata

HPV. Soft, verrucous anogenital lesions WITHOUT central indentation. Bx shows koilocytosis: perinuclear cytoplasmic vacuolization.

Councilman bodies

Hepatitis A

Subunit/conjugate vaccines

Hepatitis B, pertussis, Haemophilus type B, pneumococcal (capsular polysaccharide - T cell independent response so not for kids under 2; conjugate-polysaccharide attached to protein antigen--> T cell mediated humoral response), meningococcal, human papillomavirus, and influenza (injection)

Valproate ADE

Hepatotoxicity Neural tube defects Pancreatitis Tremor

Isoniazid toxicity

Hepatotoxicity. Peripheral neuropathy: due to interference with pyridoxine metabolism.

STD with multiple, painful, shallow ulcers with erythematous base on tender lymphadenopathy. And how to diagnose

Herpes!! Diagnose with PCR or Tzank

Why can you get gonorrhea again and again

High antigenic variability on surface. Prevents formation of immunity. Modify the pilus protein.

Propofol

Highly lipophilic anesthetic. Onset is <30 seconds and duration under 10 mins. Following bolus infusion, it's rapidly cleared from plasma and preferentially distributed to organs receiving high blood flow (ex. brain) - this accounts for rapid onset. Over time, it's redistributed to other tissues receiving less blood flow (fat, muscle). - this accounts for rapid termination.

What areas are at high risk in patients with systemic hypotension

Hippocampi: high metabolic demand. Will necrose. Watershed areas in the GI tract: splenic flexure (SMA and IMA). And rectosigmoid junction (sigmoid arteries and superior rectal arteries). And brain watershed areas.

Echinococcus granulosus

Hydatid cysts. Endemic regions and SW USA with sheep/dogs (part of tapeworm life cycle). Ingest eggs. Asymptomatic infection with subsequent manifestations depending on cyst. Liver is often affected. Infection: larvae implant in capillaries --> inflammation --> larvae encyst. Microscopic exam shows encapsulated and calcified cyst (eggshell calcification). Outer wall of gelatinous sheets surrounded by thick capsule. Treat with albendazole. Spilling of cyst in surgery --> anaphylaxis

Thiazide metabolic complications

Hypercalcemia: increased Ca2+ reabsorption (inhibits NaCl in DCT --> decreased intracellular Na+ --> activates basolateral Na/Ca antiporter which pumps Na into cell in exchange for Ca --> decreased intraluminal Ca increases Ca reabsorption. Also, it induces hypovolemia and this increases Na and water reabsorption in PCT and get passive increase in paracellular Ca2+ reabsorption) Hyperglycemia Hyperlipidemia Hyponatremia Hypokalemia

Tumor Lysis Syndrome

Hyperphosphatemia: because intracellular phosphate is much higher Hyperuricemia Hyperkalemia Elevated LDH (can form calcium phosphate stones or uric acid stones) Hyperkalemia can cause arrhythmia.

Mycobacterium avium lungs

Hypersensitivity pneumonitis. Nontuberculous mycobacterium. Acute dyspnea but can cause chronic sx. Imaging: ground glass pulmonary infiltrates. Can be acquired in pts working with hot tubs and swimming pools.