A patient with borderline tuberculoid leprosy on multidrug therapy suddenly develops swelling and erythema of existing skin lesions with severe pain along the ulnar nerve and early clawing of the little and ring fingers over 5 days. No new nodules or fever are present. The correct diagnosis and immediate management are:

• A Type 2 lepra reaction; give thalidomide and continue MDT unchanged
• B Type 1 reversal reaction; give oral prednisolone urgently and continue MDT ✓
• C Lucid phenomenon; stop MDT permanently and give clofazimine
• D Relapse of leprosy; restart MDT from scratch without steroids

Explanation

This is a type 1 (reversal) reaction: delayed hypersensitivity against M. leprae antigens in borderline spectrum patients, presenting as inflammation of pre-existing lesions plus neuritis threatening permanent nerve damage. Oral prednisolone in adequate dose (typically 40 to 60 mg daily, tapered over weeks to months) is the mainstay, and MDT is continued throughout. Thalidomide works for the humoral, TNF-alpha mediated type 2 reaction and has no role in type 1 reactions.

Reference: Harrison's Principles of Internal Medicine, 21st ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.