The lepromin test is best interpreted as which of the following?
- A An intradermal test measuring the patient's delayed hypersensitivity to M. leprae antigens, used for classification and prognosis rather than diagnosis ✓
- B A serological test that detects antibodies against phenolic glycolipid-1 and correlates with bacillary load
- C A skin test that confirms active disease when positive and must be read at 24 hours
- D A test that becomes positive only during lepra reactions and indicates treatment failure
Correct answer: A. An intradermal test measuring the patient's delayed hypersensitivity to M. leprae antigens, used for classification and prognosis rather than diagnosis
Explanation
Lepromin (Mitsuda test) injects killed M. leprae antigen intradermally and reads the late granulomatous response at 3 to 4 weeks. It reflects the host's cell-mediated immunity against M. leprae, so it is positive in the tuberculoid pole and negative in lepromatous leprosy. It is never used to diagnose leprosy because it does not distinguish infected from uninfected healthy persons in endemic areas. The Fernandez early reaction at 48 hours is a different reading.
Reference: IAL Textbook of Leprosy, 3rd ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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