Paper I
Question
Differences between tuberculoid and lepromatous leprosy
Answer
| Feature | Tuberculoid leprosy | Lepromatous leprosy |
|---|---|---|
| Host immunity | Strong cell-mediated immunity (Th1 response) | Poor cell-mediated immunity |
| Bacillary load | Paucibacillary (few/no bacilli, lepromin test positive) | Multibacillary (numerous bacilli, lepromin test negative) |
| Skin lesions | Few, well-defined, asymmetric, hypopigmented/anaesthetic patches | Numerous, ill-defined, symmetric, diffuse infiltration |
| Nerve involvement | Early, marked, asymmetric nerve thickening | Late, symmetric, diffuse nerve involvement |
| Granuloma | Epithelioid cell granulomas with Langhans giant cells (tuberculoid granuloma) | Sheets of foamy macrophages (lepra cells/Virchow cells) laden with bacilli |
| Nasal mucosa/other organs | Usually spared | Commonly involved (nasal septum destruction, “leonine facies”) |
| Prognosis | Stable, self-limiting | Progressive, more destructive if untreated |