A 35-year-old agricultural labourer presents with weakness of the right hand and clawing of fingers. There is marked thickening and tenderness of the ulnar nerve but no skin lesions anywhere on the body. Slit-skin smears are negative. Nerve biopsy shows epithelioid cell granulomas. What is the most likely diagnosis?
- A Borderline lepromatous leprosy
- B Tuberculoid leprosy with silent skin lesions
- C Pure neuritic (polyneuritic) leprosy ✓
- D Indeterminate leprosy
Correct answer: C. Pure neuritic (polyneuritic) leprosy
Explanation
Pure neuritic leprosy presents exclusively with nerve trunk involvement, commonly the ulnar, common peroneal or great auricular nerves, without any skin lesion. It is relatively more frequent in India. Diagnosis requires nerve biopsy showing granulomatous inflammation, since slit-skin smears are negative. Indeterminate leprosy shows vague hypopigmented macules rather than isolated nerve thickening, and borderline forms always have cutaneous lesions.
Reference: Park's Textbook of Preventive and Social Medicine, 27th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.