Occurrence of Pneumocystis Pneumonia in HIV-Infected Patients and the Interference of the Highly Active Antiretroviral Therapy

From the beginning of the AIDS epidemic, pneumocystis pneumonia (PCP) has been distinguished as one of the most frequent opportunistic diseases with high morbid-mortality. As from 1996, the advent of the highly active antiretroviral therapy (HAART) has changed the characteristics of such epidemic by reducing its related diseases and, as a result, AIDS-related mortality. With the purpose to estimate PCP occurrence and HAART interference, 376 HIV-infected or AIDS patients were studied from January 1992 to December 2002. Among them, 58 (15.5%) PCP cases were found. There was a higher occurrence of PCP in the group of patients in which HAART was not used, with 40 (69.0%) of the episodes. As regards the studied period, a tendency to a linear reduction in annual PCP incidence was observed. The mean of T CD4+ lymphocytes in the patients with PCP (117 cells/mm3) was significantly lower when compared to that of the other individuals (325 cells/mm3). Therefore, this study suggests a temporal reduction in PCP occurrence related to HAART use with higher T CD4+ lymphocyte counts. Nevertheless, this opportunistic infection still shows significant incidence in AIDS patients.