ID, derm, and immunology

Question 1

syphilis: tx

Answer 1

• primary through early latent (< 1y of disease) = PCN G x 1 dose
• early tertiary (gummas, neuro deficits, CV effects) or late latent (> 1y of disease) = weekly PCN G x 3 wks

Question 2

Jarisch-Herxheimer reaction

Answer 2

systemic inflammatory response 2/2 dying spirochetes when syphilis is treated

Question 3

N. meningitides meningitis prophylaxis

Answer 3

rifampin

Question 4

H. ducreyi tx

Answer 4

ceftriaxone or azithromycin

Question 5

SBP definition

Answer 5

WBC > 100 cells/mm3 and neutrophils > 50%

Question 6

tularemia tx

Answer 6

streptomycin

Question 7

serum sickness

Answer 7

type III hypersensitivity w/onset 1-3 wks after exposure or 12-36h after re-exposure > flulike sx, rash, arthralgia
- tx: withdraw agent, sx control

Question 8

most common viral cause of rhabdomyolysis

Answer 8

influenza

Question 9

2 types of nec fasc

Answer 9

type 1: polymicrobial

type 2: group A strep

Question 10

malaria tx

Answer 10

Central America/Caribbean: chloroquine

other places: artesunate

Question 11

rheumatic fever: tx

Answer 11

PCN

alternative: erythromycin

Question 12

rash w/central clearing: don’t forget

Answer 12

erythema marginatum (rheumatic fever)
not always erythema migrans (Lyme)

Question 13

transplant rejection: hyperacute vs acute vs -chronic

Answer 13

hyperacute (mins-hrs): irreversible, 2/2 preformed antibodies

acute (weeks-3m): CD8+ T-cell-mediated (type IV hypersensitivity) reaction = WBCs infiltrate graft vessels, impairing perfusion
- tx: steroids

chronic (months-years): CD4+ T-cell-mediated (types II/IV hypersensitivity) reaction = vascular intimal proliferation and renal vessel fibrosis > luminal narrowing

Question 14

dysuria w/urethral discharge in a male

Answer 14

urethritis (STI until proven otherwise)

Question 15

STI empiric tx

Answer 15

ceftriaxone 25 mg IM + azithromycin 1 g PO (or doscy 100 mg BID x 7d)

Question 16

What kind of organism is Borrelia burgdorferi?

Answer 16

spirochete

Question 17

bilateral facial nerve palsy

Answer 17

Lyme

Question 18

What infectious organism is associated with intussusception?

Answer 18

rotavirus

Question 19

pemphigus vulgaris is associated with

Answer 19

myasthenia gravis and thymoma

Question 20

DRESS syndrome

Answer 20

potentially fatal complication of AED therapy started 2-6 weeks prior: rash 1-2 weeks after nonspecific sx which initially spares mucous membranes > multi-organ system failure and death

triad: fever, rash, internal organ involvement
tx: IVIG, steroids, stop drug

Question 21

ITP

Answer 21

if PLT < 50 and active bleeding = steroids and IVIG

if PLT < 20 = steroids and IVIG regardless of bleeding/not

if life-threatening bleeding = PLT transfusion to 10

Question 22

how to differentiate: SSSS from SJS and TENS

Answer 22

SSSS spares mucous membranes

Question 23

thrush vs oral hairy leukoplakia: which scrapes off?

Answer 23

thrush…like vaginal Candida

Question 24

common drugs that cause EM

Answer 24

Sulfa, Oral hypoglycemics, Anticonvulsants, Penicillin, NSAIDs (SOAPS)

Question 25

EM minor vs major

Answer 25

minor = localized eruption of the skin with minimal or no mucosal involvement

major = one or more mucous membranes are involved

Question 26

erysipelas

Answer 26

systemic symptoms > red, demarcated rash (often malar) 2/2 S. pyogenes

Question 27

balanitis tx

Answer 27

topical clotrimazole