A 35-year-old man from rural Maharashtra presents with hypopigmented macules on his face and trunk with loss of sensation. Skin smear microscopy shows acid-fast bacilli (AFB). He is diagnosed with borderline tuberculoid leprosy and started on multidrug therapy (MDT). After 3 weeks of treatment, he develops painful erythematous nodules, fever, and worsening of existing skin lesions. What is the most appropriate next step in management?

Explanation

## Clinical Scenario Analysis The patient presents with features consistent with **Type 2 lepra reaction (Erythema Nodosum Leprosum, ENL)**: - Occurs during or after MDT in lepromatous or borderline lepromatous leprosy - Presents with painful nodules, fever, and worsening of skin lesions - Immune complex-mediated (Type III hypersensitivity) - Timing: typically 3 weeks to months into treatment ## Management of Type 2 Lepra Reaction **Key Point:** Type 2 lepra reaction is an immune complex-mediated reaction that requires continuation of MDT along with anti-inflammatory therapy. ### Immediate Management Steps 1. **Continue MDT** — stopping treatment allows bacillary multiplication and disease progression 2. **Add oral corticosteroids** — first-line anti-inflammatory agent - Prednisolone 0.5–1 mg/kg/day, tapered over 3–6 months - Effective in reducing inflammation and preventing complications 3. **Supportive care** — NSAIDs for pain and fever ### Differential Diagnosis: Type 1 vs Type 2 Lepra Reaction | Feature | Type 1 (Reversal Reaction) | Type 2 (ENL) | |---------|---------------------------|---------------| | **Timing** | During or after MDT | During or after MDT | | **Mechanism** | Cell-mediated (Type IV) | Immune complex (Type III) | | **Lesions** | Existing lesions inflame | New painful nodules | | **Systemic signs** | Mild or absent | Fever, malaise, common | | **Management** | Corticosteroids ± MDT continuation | Corticosteroids + MDT continuation | | **Thalidomide** | Not indicated | Indicated in severe/recurrent cases | **High-Yield:** ENL occurs in 50% of lepromatous and 10% of borderline lepromatous leprosy patients; it is NOT a sign of treatment failure but rather an immune reconstitution phenomenon. **Clinical Pearl:** The presence of systemic symptoms (fever, malaise) and new nodular lesions with existing lesion worsening strongly favors Type 2 reaction over Type 1. ## Why MDT Must Continue **Key Point:** Discontinuing MDT in lepra reaction is contraindicated because: - Bacilli remain viable and multiply - Disease reactivation occurs - Resistance may develop - MDT does not exacerbate the reaction; immune mechanisms do **Mnemonic:** **CONT** — **C**ontinue MDT, **O**ral corticosteroids, **N**ew nodules (ENL), **T**halidomide (if severe/recurrent)