RESUMEN
OBJECTIVE: To study incidence, risk factors, and impact of major opportunistic infections (OIs) after initiation of antiretroviral therapy (ART). METHODS: A retrospective cohort study was conducted among naïve HIV-infected patients who were initiated ART during January 2003-December 2004. All patients were followed until 15 months after ART. RESULTS: There were 793 patients with mean+/-SD age of 35.2+/-7.4 years and 56.3% male. Median (IQR) CD4 was 26 (9-78) cells/mm3. Of 793 patients, 61 (8%) patients developed 81 episodes of OIs after ART. These included tuberculosis (48.1%), CMV retinitis (19.8%), MAC infection (14.8%), PCP (9.9%), cryptococcosis (6.2%) and penicilliosis (1.2%). Overall incidence of new episode of OIs after ART was 8.0% during the first year of ART. Probabilities of OIs at 1, 2, 3, 6, and 12 months after ART were 2.6%, 4.0%, 5.3%, 6.9% and 8.0%, respectively. Baseline CD4 < or = 50 cells/mm3, male gender, and low body weight were associated with higher incidence of OIs after ART (P<0.05). CONCLUSIONS: Most of new episodes of major OIs develop within the first three months after ART. Tuberculosis is the most frequent OIs in this situation. The substantial increase of new episode of OIs after ART was observed among HIV-infected patients with CD4 cell counts < or = 50 cells/mm3 at ART initiation.