Spectrum of pulmonary diseases associated with the acquired immune deficiency syndrome.

Over a four-year period, 130 patients with the acquired immune deficiency syndrome were studied to assess the incidence and spectrum of pulmonary disease associated with this illness. In 61 patients (47 percent), respiratory abnormalities were either present on admission or later developed. Multiple pathologic processes were present simultaneously in 24 patients and serial pulmonary problems developed in seven patients. Infection was the most common cause of pulmonary parenchymal disease and was due to Pneumocystis carinii (35 patients), cytomegalovirus (21 patients), Mycobacterium avium-intracellulare (13 patients), and bacteria (four patients). Noninfectious causes of parenchymal lung diseases were also frequently seen and included Kaposi's sarcoma (eight patients), non-specific pneumonitis (seven patients), and adult respiratory distress syndrome (four patients). Significant pleural disease was present in six cases and was usually related to Kaposi's sarcoma. A bronchospastic disorder developed in four patients. Pulmonary function tests, in particular the diffusing capacity and the difference between rest and exercise alveolar-arterial oxygen tension, were helpful in screening for pulmonary diseases. Patterns of clinical features and radiographic abnormalities were recognized and suggested specific diagnoses. Overall mortality from respiratory causes identified during the study was 41 percent, but varied markedly with the etiologic agent. Respiratory failure, however, carried a 100 percent mortality despite the underlying cause.