Pneumocystis carinii pneumonia: CT and HRCT observations.

We examined the chest radiography, CT, and high resolution CT (HRCT) of 14 patients with proven Pneumocystis carinii pneumonia. We compared the radiographic and HRCT patterns of abnormal lung parenchyma with histologic sections obtained in those 11 patients who had had transbronchial lung biopsies. Diffuse bilateral perihilar airspace disease was the most common radiographic pattern. Both CT and HRCT showed "ground glass" opacity in the lungs, through which the vessels remained visible in all patients. No enlarged lymph nodes or pleural effusions were seen in patients without associated lymphoproliferative disorders.