Nonspecific interstitial pneumonitis in patients with AIDS: radiologic features.

Chest radiographic abnormalities in patients with AIDS usually are associated with opportunistic infection or neoplasm. One hundred five patients with AIDS and clinical evidence of pneumonitis had chest radiographs and underwent bronchoscopy with bronchoalveolar lavage, transbronchial biopsy, or open-lung biopsy. Chest radiographs were abnormal in 73 (70%). Pneumocystis carinii pneumonia was identified at bronchoscopy or open-lung biopsy in 52 (50%). Nonspecific interstitial pneumonitis occurring in the absence of an identifiable infection was documented histologically in 36 (34%). Twenty (56%) of these 36 patients had abnormal chest radiographs. No currently recognized infectious agents were recovered from lavage fluid or were seen histopathologically in patients with nonspecific interstitial pneumonitis. The results show that nonspecific interstitial pneumonitis is clinically and radiologically indistinguishable from Pneumocystis carinii pneumonitis and should be considered in the differential diagnosis of AIDS patients with interstitial infiltrates.