A 35-year-old with AIDS (CD4 count 40 cells/μL) develops fever and generalized lymphadenopathy. Lymph node biopsy shows macrophages loaded with AFB but no granuloma formation. The most likely diagnosis is:

• A Tuberculosis with miliary spread
• B Lepromatous leprosy
• C Disseminated Mycobacterium avium-intracellulare complex (MAC) ✓
• D Mycobacterium kansasii infection

Explanation

Disseminated MAC is the most common non-tuberculous mycobacterial infection in advanced HIV disease (CD4 <50 cells/μL). The profound immunosuppression prevents granuloma formation, resulting in macrophages stuffed with AFB without organized granulomas. This histological picture resembles lepromatous leprosy. MAC causes systemic disease with persistent fever, night sweats, weight loss, diarrhea, and hepatosplenomegaly. Clarithromycin plus ethambutol is the treatment regimen of choice; azithromycin is used for prophylaxis when CD4 <50.

Reference: Ananthanarayan & Paniker's Textbook of Microbiology, 11th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.