Use of bronchoalveolar lavage to diagnose acute diffuse pneumonia in the immunocompromised host.

We compared the diagnostic information obtained by bronchoscopy and needle aspiration of the lung with information obtained concurrently by open-lung biopsy in 15 marrow transplant recipients. Bronchoscopy included a wash, brush, and bronchoalveolar lavage. Laboratory evaluation included standard histological and cytological methods, specific immunofluorescence with monoclonal antibodies, and DNA hybridization to detect cytomegalovirus (CMV). Bronchoscopy permitted diagnosis of five of six patients with CMV pneumonia, whereas needle aspiration alone permitted diagnosis of only one of six. Bronchoalveolar lavage alone provided the diagnosis in four of six patients. Bronchoscopy also identified the bacterial component of a combined infection and identified one case of primary lung hemorrhage. Immunofluorescent staining and hybridization studies each diagnosed one case of CMV pneumonia not identified by standard techniques. The diagnostic sensitivity of the bronchoscopy was 89%, as compared with 17% for needle aspiration, and there were no complications.