Investigation of the Role of the Cytomegalovirus as a Respiratory Pathogen in HIV-Infected Patients

Abstract

OBJECTIVE: To investigate the occurrence of cytomegalovirus (CMV) pneumonitis in the setting of human immunodeficiency virus (HIV) infection and whether the presence of CMV as copathogen is associated with increased clinical severity or short term mortality in patients with Pneumocystis carinii pneumonia.DESIGN: Retrospective cohort study.SETTING: Tertiary care university hospital.PATIENTS: One-hundred and fourteen HIV-infected homosexual men with pneumonia, followed for a minimum of four weeks.MEASUREMENTS: Clinical indicators of severity of pneumonia, microbiology of bronchoalveolar fluid and relative risk of short term mortality.RESULTS: Only two cases of CMV pneumonitis were found, one together with P carinii. However, 45 of the 86 patients with P carinii pneumonia were co-infected with CMV. No difference in clinical severity was detected between patients co-infected with P carinii and CMV and those with P carinii alone. The relative risk of short term mortality was 3.64 (95% CI 0.82 to 16.18), in patients with co-infection compared with those with P carinii alone. The risk reached statistical significance for patients with earlier stages of HIV infection.CONCLUSIONS: CMV pneumonitis occurs rarely in HIV-infected patients, while CMV co-infection occurs in at least 50% of the cases of P carinii pneumonia. Although no difference in clinical severity was detected, this study suggests that short term mortality from P carinii pneumonia may be increased by CMV co-infection, particularly in patients with earlier stages of the disease.