Dermatology cases

Question 1

24 year old woman has itchy lesions on the flexor surfaces of her wrists. The lesions are polygonal purple papules.

a) Likely diagnosis
b) Other possible feature to support this
c) Management

Answer 1

a) Lichen planus - purple, pruritic, polygonal papules
b) White lacy lesions on inside of cheeks

c) - Often no treatment required, usually resolves in 1 yr
- Symptomatic: topical steroids / antihistamines

Question 2

14 year old boy presents with intensely itchy vesicular rash on an erythematous base, affecting the buttocks, elbows and knees.

a) Diagnosis
b) Investigations
c) Management

Answer 2

a) Dermatitis herpetiformis

b) - Skin biopsy
- Coeliac serology (total IgA and IgA TTG)

c) - Gluten free diet
- Oral dapsone

Question 3

A 17 year old girl was started on the COCP and presents with tender red lesions on her shins

a) Diagnosis
b) Other causes of this
c) Treatment

Answer 3

a) Erythema nodosum
b) Idiopathic, IBD, sarcoid, TB, antibiotics

c) - Stop precipitant
- Most cases are self-limiting - NSAIDs if required
- If IBD flare-up, probably responds to oral steroids

Question 4

Previously fit and well 24 year old male presents with painful violaceous lesions on the shins. Started as pustules, which coalesced.

Answer 4

a) Pyoderma gangrenosum