Dermatology

Question 1

Causes erythema multiforme

Answer 1

1. Infections- HSV, mycoplasma pneumonia
2. Drugs- NSAIDs, antieplileptics, antibiotics (sulfa, PCN, erythromycin, nitrofuratoin, tetracyclines
3. IBD
4. Ca- lymphoma, leukemia, solid organ (renal cell)

Question 2

Erythema multiforme appearance

Answer 2

Pink, red papules that become plaques

• cause itching and burning
• develop into multiple types of lesion, classic is target lesion
• more on extensor surfaces and symmetric
• spread centripedally (starts on extremities and moves to trunk)
• mucosal lesions in 25-60% (more often systemic symptoms)

Question 3

Treatment erythema multiforme

Answer 3

Most resolve spontaneously in 2-4 weeks

Question 4

Persistent erythema multiforme

Answer 4

Associated with:

• malignancy
• IBD
• hep C
• HSV, EBV, CMV

Question 5

Tx erythema multiforme

Answer 5

Supportive, antihistamines, steroids
Stop offending drug
Antivirals don’t really work, but can help if recurrent HSV with using daily ppx
Month long pred taper if severe symptoms
If ocular involvement need referral to ophtho

Question 6

valacyclovir dosing shingles

Answer 6

1000 mg po q8hr x7 days