The impact of concomitant viral pathogens on the course of Pneumocystis carinii pneumonia.

A large retrospective study was conducted to evaluate the impact of culturing cytomegalovirus from the respiratory secretions of AIDS patients with Pneumocystis carinii pneumonia. Pneumocystis carinii was found in 220 (67%) of 327 episodes and cytomegalovirus was found in 106 (48%) of the P. carinii-positive patients. Cytomegalovirus-positive and -negative patients were similar at baseline and had a similar number of hospital days, but had a lower incidence of early deterioration in oxygenation, fewer intensive-care days, were less frequently intubated, and had a higher 30-day survival. The better short-term outcome of cytomegalovirus positive patients observed in this study may relate to the immunosuppressive effects of cytomegalovirus.