skip to main content

TB Reactivation — SCE Dermatology MCQ

Instant feedback + full explanation. One question, done properly.

HardDermatopharmacologyTB ReactivationSCE Dermatology

A 60-year-old woman develops erythema and tenderness at the site of a BCG vaccination scar following the start of treatment with an anti-TNF biologic for psoriasis. What does reactivation at a BCG scar during biologic therapy suggest?

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

Reveal the answer and explanation

Correct answer: D — Possible tuberculosis reactivation requiring urgent investigation

Reactivation of BCG scar (erythema, swelling, ulceration at the BCG vaccination site) during immunosuppressive therapy, particularly anti-TNF biologics, can indicate mycobacterial reactivation and should be treated as a warning sign for possible TB. While BCG scar reactivation can occur in other inflammatory conditions (Kawasaki disease, sarcoidosis), in the context of biologic therapy it warrants urgent investigation including IGRA testing, CXR, and infectious diseases consultation. The biologic should be withheld pending investigation. This phenomenon has been reported with multiple biologic agents and serves as a clinical prompt for TB assessment.

Reference: BAD 2020 Biologic Guidelines; NICE NG33 TB