A 30-year-old woman presents with a well-defined erythematous plaque on the cheek with follicular plugging, adherent scales, and central scarring. Removing the scale reveals carpet-tack sign on the undersurface. What is the diagnosis?
- A Systemic lupus erythematosus
- B Discoid lupus erythematosus ✓
- C Subacute cutaneous lupus erythematosus
- D Rosacea
Correct answer: B. Discoid lupus erythematosus
Explanation
Discoid lupus erythematosus (DLE) presents as a coin-shaped (discoid) erythematous plaque with follicular plugging, scaling, and central atrophic scarring, predominantly on sun-exposed areas. The carpet-tack sign refers to the spiky follicular plugs on the undersurface of the removed scale, corresponding histologically to hyperkeratotic plugs in follicular ostia. DLE is a chronic scarring photosensitive dermatosis that remains localized in the majority; only about 5% progress to systemic lupus. ANA is positive in only 5-10% of DLE cases.
Reference: Neena Khanna Illustrated Synopsis of Dermatology & STD, 6th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.