Lucio phenomenon is a severe form of leprosy reaction characterized by necrotizing arteritis. It occurs exclusively in patients with which type of leprosy?
- A Tuberculoid leprosy (TT)
- B Borderline lepromatous (BL) leprosy
- C Non-reactive (pure) diffuse lepromatous leprosy (Lucio leprosy) ✓
- D Borderline tuberculoid (BT) leprosy during type 1 reaction
Correct answer: C. Non-reactive (pure) diffuse lepromatous leprosy (Lucio leprosy)
Explanation
Lucio phenomenon is a severe cutaneous vasculitis that occurs exclusively in patients with diffuse, non-nodular lepromatous leprosy (Lucio leprosy), a variant especially seen in Mexico and Latin America. Histologically it shows endothelial invasion by M. leprae causing necrotizing small-vessel arteritis, leading to haemorrhagic infarcts and sloughing of skin. It is not a classic Type 1 or Type 2 reaction and is distinct from ENL.
Reference: Neena Khanna Illustrated Synopsis of Dermatology & STD, 6th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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