The changing face of Pneumocystis carinii pneumonia in AIDS patients.

The classic presentation of PCP is a bilateral interstitial pattern, which may be characterized as finely granular, reticular, or ground-glass opacities. When chest radiographic findings are normal or equivocal, high-resolution CT may be helpful because it is more sensitive than chest radiography for detecting PCP. The typical CT finding is extensive ground-glass attenuation. The face of PCP is changing. The classic radiographic presentation is being encountered less frequently. Increasingly recognized characteristic patterns of PCP include cystic lung disease, spontaneous pneumothorax, and an upper lobe distribution of parenchymal opacities. The spectrum of abnormalities associated with PCP is broadening and now includes abnormalities of the lung parenchyma, airways, lymph nodes, and pleura. An awareness of the varied presentations of PCP is important because the radiologist is often the first to suggest the diagnosis of PCP.