A man from Ethiopia presents with symmetric, non-ulcerated nodules diffusely covering the face and extensor surfaces, clinically resembling lepromatous leprosy. Slit skin smear shows abundant amastigotes and the leishmanin test is negative. The underlying defect and likely species are:

• A Specific failure of cell-mediated immunity to Leishmania, caused by Leishmania aethiopica ✓
• B Humoral immunodeficiency, caused by Leishmania major
• C Complement deficiency, caused by Leishmania infantum
• D Impaired neutrophil chemotaxis, caused by Leishmania braziliensis

Explanation

Diffuse cutaneous leishmaniasis is an anergic variant in which parasite-specific cell-mediated immunity fails, giving disseminated nodules teeming with amastigotes and a negative leishmanin test. In Ethiopia it follows L. aethiopica infection. The main differential is lepromatous leprosy, excluded here by demonstrating amastigotes rather than acid-fast bacilli.

Reference: Rook's Textbook of Dermatology, 9th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.