Cotrimoxazole prophylaxis in HIV — DTM&H MCQ

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ModerateHIV/AIDS in tropical settingsCotrimoxazole prophylaxis in HIVDTM&H

A 33-year-old woman with newly diagnosed HIV in rural Zambia has CD4 count 128 cells/microlitre and chronic weight loss. She has no sulfonamide allergy and is starting ART next week. What is the most appropriate prophylaxis?

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Correct answer: B — Cotrimoxazole prophylaxis

The correct answer is B, cotrimoxazole prophylaxis. This woman has advanced HIV disease (CD4 128 cells/microlitre, well below the 200 to 350 cells/microlitre threshold, with wasting suggestive of WHO clinical stage 3 or 4), which is the specific indication for co-trimoxazole primary prophylaxis in resource-limited settings such as rural Zambia. Co-trimoxazole (as trimethoprim-sulfamethoxazole) prevents Pneumocystis jirovecii pneumonia and toxoplasmosis, and in high-transmission settings also reduces bacterial sepsis, diarrhoeal illness and malaria episodes, cutting mortality in advanced HIV disease. It should be started promptly and continued alongside, not instead of, ART, which is the definitive long-term intervention; she has no sulfonamide allergy, removing the main contraindication. Why the other options are wrong: E. Fluconazole lifelong for every patient: routine universal antifungal prophylaxis is not recommended; fluconazole is reserved for treatment or secondary prophylaxis after confirmed cryptococcal disease, not given blanket to all patients regardless of CD4 or symptoms. D. Weekly mefloquine prophylaxis: this is a travel chemoprophylaxis regimen for non-immune visitors to malaria-endemic areas, not a recognised HIV-related opportunistic infection prophylaxis for a resident of an endemic area with advanced immunosuppression. A. Praziquantel every month: praziquantel treats established schistosomiasis or other trematode infections; it has no role as a scheduled monthly prophylactic agent in HIV care. C. Benzathine penicillin monthly: this is secondary prophylaxis for rheumatic fever, not indicated in HIV management and irrelevant to her presenting immunosuppression and weight loss. Key point: co-trimoxazole prophylaxis is indicated in advanced HIV disease (CD4 below 200 to 350 cells/microlitre or WHO stage 3 or 4) and should be started without delaying ART initiation.

Reference: WHO Guidelines on Post-Exposure Prophylaxis for HIV and the Use of Co-trimoxazole Prophylaxis for HIV-Related Infections Among Adults, Adolescents and Children (recommendation: co-trimoxazole prophylaxis for CD4 count ≤350 cells/mm3 or WHO clinical stage 3/4) https://www.ncbi.nlm.nih.gov/books/NBK298965/