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Block 5 Case 2

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Normal liver span and location:
Total span 6-12cm.

No more than 2-3cm below costal margin.
Value and ddx of widened pulse pressure...
>65 mm Hg

Aortic dissection, valvular regurg, AAA, Anemia, Restrictive cardiomyopathy, Hyperthyroid, Graves disease, Age (decreased aortic compliance)
Value and ddx of narrowed pulse pressure...
<30 mm Hg

Cardiac Tamponade, aortic stenosis, hypothyroidism, extreme hemorrhage or volume loss
ALT: Primary purpose
Sensitive and specific for hepatocellular disease.
AST: Primary purpose
Coronary artery occlusive diseases OR hepatocellular.

Found in high metabolic tissue (heart, liver, skeletal muscle... some kidneys)
Elevted AST indicates...
CV diseases
Liver diseases
Skeletal muscle disease
Other: acute hemolytic anemia or pancreatitis.
Rapid strep test, methods and sensitivity/specificity
Enzyme immunoassay, optical immunoassay, chemiluminescent DNA probe.

70-95% sensitivity
>95% specificity
Centor score criteria
history of fever
tonsillar exudates
anterior cervical adenopathy
absence of cough
Centor score of 1 in presence of negative rapid strep?
No testing, no treatment
Centor score of 2,3,4 in presence of negative rapid strep?
Throat culture for both children & adults.
ASO: timeline
Shows up 1week - 1 month after streptococcal infection
ASO: Significance of rising titer vs single elevated value
Rising is more significant.
ASO: diagnostic use
CANNOT be used to diagnose acute strep infection.
Elevated in 70-80% of acute rheumatic fever cases.
ASO: combined with what to get what sensitivity?
Anti-DNase-B... an immunologic test that when combined with ASO is 95% sensitive.
Rofecoxib: trade name, class, MOA, side effects
Vioxx, NSAID
selective COX-2 inhibitor -> decreased prostaglandin synthesis
Withdrawn due to risk of MI and stroke.
Dopamine: uses, MOA (low, medium, high doses), side effects
Treatment for shock due to renal failure, CHF etc.
1) Low dose: stimulates dopaminergic receptors->renal and mesenteric vasodilation
2) Medium: cardiac stimulation and renal vasodilation -> increased cardiac output, renal perfusion.
3)High: alpha-adrenergic receptors lead to vasoconstriction, increased BP
Milrinone: uses, MOA, adverse effects
short term IV therapy for CHF and calcium anatgonist intoxication
phosphodiesterase inhibitor -> increased intracellular calcium and increased contractility.
long term use >48h leads to increased mortality
Furosemide: uses, MOA, adverse effects
management of edema, HT
inhibits NA/CL/K transporter in ascending loop of Henle
can lead to electrolyte imbalance: hypo- kalemia, chloremia, calcemia, natremia etc.
Vancomycin: class, MOA, uses
Glycopeptide antibiotic for gram+
MOA: binds to cell wall percursors (NOT same as penicillin) increasing permeability, also inhibits RNA synthesis... dual action = less resistance. CANNOT ENTER GRAM - CELLS.
Useful in MRSA, penicillin allergy.
Meropenem: class, MOA, uses, adverse effects
Carbapenem antibiotic
Inhibits cell wall formation at PBP, very resistant to beta-lactamases
excellent vs aerobic and anaerobic!
lower risk of seizure compared to imipenem!
Doxycycline: class, MOA, pharmacokinetics, adverse effects
tetracycline antibiotic
bacteriostatic vs both gram + and - by binding to 30S ribosomal subunit and inhibiting protein synthesis... humans cannot active transport it in, immune.
Oral absorption delayed by food, esp milk.
UNSAFE DURING PREGNANCY, CLASS D!!
Methylprednisolone: class, MOA, uses, adverse effects
synthetic glucocorticoid
binds to cytosolic receptors, translocate to nucleus, modifies transcription.
Used in SLE, RA, vasculitis, poly and dermatomyositis...
Adverse: HPA axis suppression, osteoporosis, etc.... all dose dependant.
Viral myocarditis: causes
Coxsackievirus (most common)
adenovirus
CMV
echovirus
EB virus
Hep C
Myocarditis: non-viral causes
bacteria, fungi, parasites, drugs, toxins, immunologic disorders
Viral myocarditis: pathophysiology
inflammation of myocardium leads to necrosis of myocytes and inflammatory infiltrate... leads to heart failure.
Viral myocarditis: symptoms
Follows viral URI.
Chest pain, heart failure, arrhythmia, dyspnea and fatigue.
Viral myocarditis: physical exam
Tachy, S3, murmur
JVD, edema
fatigue
fever
Viral myocarditis: Labs
high WBC, lymphocytosis
LDH, CK-MB, troponin up
bacterial cultures negative if viral
Viral myocarditis: Imaging
CXR: cardiomegaly, pul. edema
Echo: wall abnormalities
EKG: sinus tachy, low voltage QRS, T wave flattening or inversion.
Viral myocarditis: Dx gold standard
endomyocardial biopsy showing lymphocytic inflammation.
Viral myocarditis: treatment
admit due to risk of deterioration.

Usually selflimiting: support with O2, BiPAP, diuretics, inotropic agents, possibly corticosteroids.
ARF: epidemiology
US: 5-10:1000
High in developing world.
Males = females.
Follows .3% of GAS infection.
ARF: clinical manifestations
High fever, tachycardia.
Cardiomegaly, CHF, pericarditis, murmurs.
SubQ nodules, erythema marginatum.
Arthralgia, migratory polyarthritis.
Sydenham's Chorea -- involuntary purposeless dancelike movements
ARF: onset related to?
delayed sequelae to group A strep of PHARYNX. NOT after skin infection.
ARF: Carditis
Most serious manifestation
PANcarditis... inflammation of all 3 layers.
ASCHOFF bodies found in myocardium... swollen eosinophilic collagen surrounded by T cells.
ARF: erythema marginatum
rash found on trunk and proximal parts of extremities... never on face!

expanding rash, older areas return to normal.
ARF: 3 theories of pathogenesis
1) toxic effects of strepolysin O or A

2) serum sickness reaction

3) Antibodies against M proteins crossreact with glycoprotein antigens in heart, joints and other tissues.
ARF: post-disease risks
increased vulnerability to future attacks with _pharyngeal infections_. Each attack is worse since damage is cumulative.
ARF: Jones criteria requirements
2 Major OR 1 major/2 minor PLUS evidence of prior strep infection
ARF: Jones criteria major
Major: Carditis, Polyarthritis, Chorea, Erythema marginatum, subQ nodules
ARF: Jones criteria minor
Minor: Fever, arthralgia, previous RA, increased acute phase reactants or increased PR interval
ARF: Jones criteria evidence of prior GAS infection
Increased ASO or other strep antibodies.

Positive throat culture for GAS.

Positive rapid strep test.

Recent Scarlet fever.
ASO elevated values in adults and kids.
Adult: >250U

Child: >333U
Next step after negative ASO in suspected ARF?
Test anti-DNAase B, anti-DNAse and anti hyaluronidase.
Normal PR interval, indication if long:
.12 - .20s

Indicates AV block.
Normal QRS interval, indication if long:
.04 - .12s

Indicates BBB.
EKG signs of hypertrophy:
Diphasic P wave in V1 for Atrial enlargement.

R wave in V1 for RVH.

S wave V1+R wave V5 > 35mm for LVH.
EKG signs of infarction:
Q waves >1mm wide or 1/3 QRS amplitude.

Inverted T waves... opposite QRS, indicates ischemia.

ST segment elevation (acute) or depression (old infarct)
S. aureus: ID
Gram +, Catalase +, Beta hemolytic, Coagulase +
S. aureus: virulence factors
Protein A: binds to IgG, protecting from phagocytosis.

Penicillinase: inactivates PCN

Exfoliatin: skin sloughs

Enterotixins: N/V/D

TSST-1: toxic shock syndrome
S. aureus: antibiotics
Penicillinase resistant PCNs.

Vancomycin.

Clindamycin.
S. Marcescens: ID
Gram - bacillus, Motile, produces red/pink dye
S. Marcescens: Antibiotics
Cephalosporins, gentamicin.
Candida albicans: ID
Yeast-like fungi, hyphae and pseudohyphae.

Large, round, white colonies on agar.
Candida albicans: antibiotics
Cutaneous: -azoles (fluconazole)

Invasive: agument -azoles with Amphotericin B.
Candida albicans: associated disease
Oral thrush
Vaginitis (yeast infection)
Diaper rash

Candidemia (catheters, immunocompromised!)
Disseminiated candiasis
Aschoff bodies, morphology:
Foci of swollen eosinophilic collagen surrounded by lymphocytes, plasma cells, and macrophages.
Aschoff bodies: location
All 3 layers of heart, most commonly endocardium.
Chronic rheumatic fever: changes
thickening of mitral valve leading to stenosis, scarring where Aschoff bodies were, thickening of chordae tendinae.
ARF: describe erythema marginatum
Rash with paler center and rounded raised margins!
Heart murmurs: 5 auscultary areas
Aortic: 2nd right IC space
Pulmonic: 2nd left IC space
Pulmonic2: 3rd left IC space
Tricuspid: 4th left IC space
Mitral: apex at 5th IC space
Heart murmurs: grades
I: barely audible
II: quiet but clearly audible
III: moderately loud
IV: Loud with thrill
V: very loud, easily felt thrill
VI: very loud, audible w/o stethoscope, thrill very easily felt.
Heart murmurs: signs of pathological murmur
Symptoms (dyspnea, cyanosis etc)
Diastolic murmur (always bad)
Systolic click, opening snaps
S4 gallop
Benefits of mechanical vs bioprosthetic values
Mechanical: last 20-30 years
Bioprosthetic: last 10-15 years, but require no thrombolytics.

Mechanical if young, can take warfarin.

Bio if old, or can't take warfarin.
Ejection fraction threshold for left ventricular dysfunction:
< 50%.
3 post valve replacement syndromes:
postpericardiotomy syndrome: fever, pleuritis, pericarditis.

Postperfusion syndrome: fever, splenomegaly, lymphocytosis. From CMV in blood transfusions

Cardiac tamponade.
INR recommendations in valve replacement:
2-3: Normal mechanical valve
2.5-3.5: previous embolus, AFib, or mitral valve
3-4.5: tilted disc valve... highly thrombogenic
Poststrep Glomerulonephritis: strains
GAS strains 12,4,1 most cause 90%.
Poststrep Glomerulonephritis: time frame
10 days after pharyngitis (or 1-2 weeks)
2 weeks after impetigo (or 3-6 weeks)

Depends on source
Poststrep Glomerulonephritis: pathophysiology
Immune complex deposition of strept antigens and autoimmune reactivity.
Poststrep Glomerulonephritis: Labs
Creatinine elevated.
Complement (C3, CH50) low.
Circulating antibodies vs GAS: ASO, antiDNAse B etc.
Poststrep Glomerulonephritis: micro findings
Large, hypercellular glomeruli.
Humps on epithelial side of golmeruli.
Poststrep Glomerulonephritis: treatment and prognosis
Diuretics, !hypertensives, steroids to manage HTN, ECF volume, inflammation.

Good prognosis, rarely causes end stage renal disease.
Polyethylene glycol: trade name, class, MOA, Adverse effects
Miralax
Laxative
osmotic agent causing water retention in stool
Can lead to electrolyte imbalance or dependance.
Warfarin: trade name, class, MOA, adverse effects
Coumadin
Anticoagulant
Interferes with epoxide reductase, stopping vitamin K conversion from inactive to active. Effectively causes Vit K deficency.
Hemmorrhage. Treat with FFP and Vit K. PREGNANCY CLASS X! Use heparin.
Vitamin K dependant clotting factors:
II, VII, IX, X, protein C and S.
Spironolactone: class, use, moa, adverse effects
potassium sparing diuretic
HTN, edema from CHF, cirrhosis etc.
Synthetic steroid and competitive antagonist of aldosterone.
Hyperkalemia, hyponatremia etc.
L-thyroxine: class, use, MOA, adverse effects
thyroid agent
hypothyroidism, hyper TSH secretion
Same as endogenous. Suppresses TSH by feedback.
Overdose -> symptoms of hyperthroidism
Differin Gel: trade name, class, uses, MOA, adverse effects
Adapalene
Retinoid Dermatologic
Acne
Acts at retinoic acid receptors to modulate cellular differentiation, keratinization, inflammatory process.
Avoid sunlight, tanning etc.

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