Initiating co-trimoxazole prophylaxis in HIV-infected patients in Africa: an evaluation of the provisional WHO/UNAIDS recommendations

Objective: To evaluate the proposed WHO/UNAIDS criteria for initiating co-t rimox-azole prophylaxis in adult HIV-infected patients in Africa [WHO clini cal stages 2-4 or CD4 count < 500 x 10(6) /l or total lymphocyte count (TLC ) equivalent]. Design: Observational cohort study of 5-year follow-up. Setting: Adult HIV clinics, University of Cape Town, South Africa. Methods: Effect of prophylactic low dose co-trimoxazole (480 mg per day or 960 mg three times per week) on survival and morbidity was assessed in pati ents stratified by WHO clinical stage, CD4 T-lymphocyte count or TLC. Patie nts receiving antiretroviral therapy were excluded. Results: Co-trimoxazole reduced mortality [adjusted hazard ratio (AHR), 0.5 6; 95% confidence interval (CI), 0.33-0.85; P > 0.001] and the incidence of severe HIV-related illnesses (AHR, 0.52; 95% CI, 0.38-0.68; P < 0.001) in patients with evidence of advanced immune suppression on clinical (WHO stag es 3 and 4) or laboratory assessment (TLC < 1250 x 10(6)/l or CD4 count < 2 00 x 10(6)/l). No significant evidence of efficacy was found in patients wi th WHO stage 2 or CD4 count 200-500 X 10(6)/l/TLC 1250-2000 X 10(6)/l. If w e had applied the WHO/UNAIDS recommendations 88.3% of our patients would ha ve received co-trimoxazole prophylaxis at their initial clinic visit. Conclusion: Co-trimoxazole in HIV-infected adults from an area in which Pne umocystis carinii pneumonia is uncommon demonstrated a survival benefit con sistent with previous randomized trials. Further studies are needed to asse ss the optimal time of commencement of prophylaxis, as widespread co-trimox azole use will lead to increasing antimicrobial resistance to other major p athogens in Africa. (C) 2001 Lippincott Williams & Wilkins.