A 30-year-old man with known lepromatous leprosy on multidrug therapy develops multiple firm, shiny, skin-coloured nodules over the face and trunk. Biopsy shows spindle-shaped histiocytes arranged in interlacing whorls, stuffed with acid-fast bacilli. What is this lesion called?
- A Lucio phenomenon
- B Histoid leprosy ✓
- C Borderline tuberculoid upgrade
- D Erythema nodosum leprosum
Correct answer: B. Histoid leprosy
Explanation
Histoid leprosy is a distinctive variant of lepromatous leprosy presenting as firm cutaneous and subcutaneous nodules that resemble dermatofibromas clinically. Histology shows spindle-shaped or polygonal histiocytes in storiform whorls packed with bacilli, unusually well demarcated for lepromatous disease. It may arise de novo or during inadequate therapy and carries a very high bacterial index. Lucio phenomenon is a diffuse necrotizing vasculitic reaction seen in diffuse lepromatous leprosy.
Reference: Robbins and Cotran Pathologic Basis of Disease, 10th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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