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Dapsone Toxicity — SCE Dermatology MCQ

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HardDermatopharmacologyDapsone ToxicitySCE Dermatology

A patient with ulcerative colitis has a rapidly expanding painful leg ulcer with a violaceous undermined edge. Cultures and deep-tissue assessment show no invasive infection. The ulcer enlarged after two sharp debridements, and an edge biopsy shows neutrophilic inflammation. Which wound-management change is most important during active disease?

Educational content. Not a substitute for clinical judgement or local policy.

Reveal the answer and explanation

Correct answer: E — Avoid wide debridement; use atraumatic wound care while controlling inflammation

Explanation lettering: D = shown as B · E = shown as C · C = shown as D · B = shown as E

B is correct. The phenotype and neutrophilic edge histology support pyoderma gangrenosum after invasive infection has been assessed. Trauma can provoke pathergy, so repeated or wide surgical debridement during active inflammation may enlarge the ulcer. Management combines control of inflammation with gentle dressings, analgesia and treatment of associated disease. Negative-pressure therapy or reconstruction can sometimes assist selected controlled disease, but they are not substitutes for suppressing active inflammation and require an atraumatic multidisciplinary plan. Antibiotics treat documented secondary infection rather than the sterile neutrophilic process.

Reference: DermNet pyoderma gangrenosum: https://dermnetnz.org/topics/pyoderma-gangrenosum