[Pneumocystis carinii pneumonia (pneumocystosis)].

In former times Pneumocystis carinii (PC) primarily affected premature infants. More recently, it has proved to be one of the major infectious complications among immunocompromised patients, particularly those with AIDS. The most frequent radiographic feature is diffuse, bilateral alveolar and interstitial perihilar shadowing, spreading in a butterfly pattern. The typical findings may mimic other infectious diseases, but the presence of large pleural effusions of hilar adenopathy is evidence against the diagnosis of PC-pneumonia.