Geographic clustering of Pneumocystis carinii pneumonia in patients with HIV infection.

To detect whether there was geographic clustering of Pneumocystis carinii pneumonia cases among patients with human immunodeficiency virus (HIV) infection, we performed a retrospective analysis of a clinical database. The rates of pneumocystosis were analyzed by zip code zones for evidence of geographical clustering. During the study period, 118 patients at our AIDS Treatment Center had a first episode of P. carinii pneumonia. An analysis of the 24 zip code zones for which a P. carinii pneumonia rate was calculated (requiring a denominator of at least 10 known HIV- infected individuals residing in that zone) showed a trend toward geographic clustering (p = 0.07); when all 45 Cincinnati zip code zones were included in the analysis, clustering of cases was observed (p = 0. 02). By contrast, no clustering was observed for 52 HIV-infected control subjects with respiratory disease or for 960 HIV-infected patients treated at our center during the same time period. These data raise intriguing questions about exposure to exogenous sources of P. carinii and suggest the need for prospective studies.

Equal survival rates for first, second, and third episodes of Pneumocystis carinii pneumonia in patients with acquired immunodeficiency syndrome.

BACKGROUND: Second and subsequent episodes of acute Pneumocystis carinii pneumonia (PCP) are reported to have a worse prognosis than initial episodes in patients with the acquired immunodeficiency syndrome. We tested the hypothesis that survival rates of first, second, and subsequent episodes of acute PCP in patients with the acquired immunodeficiency syndrome are equal. METHODS: Analysis of the outcomes in prospective series of patients with the acquired immunodeficiency syndrome treated for acute PCP over 5 years. RESULTS: Survival rates of 222 PCP occurrences by episode number were: first, 86%; second, 84%; third, 88%; and fourth, 67%. Survival rates for the first, second, and third episodes were not significantly different. Second and third episodes had a larger proportion of patients with mild disease than initial episodes. CONCLUSIONS: Survival rates for first, second, and third episodes of PCP in patients with the acquired immunodeficiency syndrome are not different. In contrast to earlier articles, treatment for second and third episodes of acute PCP may be as successful as in initial episodes.