Chest, Vol 94, 580-583, Copyright © 1988 by American College of Chest Physicians

ARTICLES

Granulomatous Pneumocystis carinii pneumonia in three patients with the acquired immune deficiency syndrome

IJ Bleiweiss, JS Jagirdar, MJ Klein, JL Siegel, DJ Krellenstein, AR Gribetz and JA Strauchen
Department of Pathology, Mt Sinai Medical Center, New York, New York 10029.

Pneumocystis carinii pneumonia is a frequent manifestation of the acquired immune deficiency syndrome (AIDS). It usually presents radiologically as diffuse bilateral infiltrates and histologically as a foamy, eosinophilic intra-alveolar exudate containing the organisms' cysts. We recently studied two rare cases of P carinii pneumonia presenting as pulmonary nodules on chest x-ray films in two patients with AIDS. The corresponding histologies were a combination of the usual intra-alveolar pattern, with an alveolar and interstitial granulomatous appearance. Pneumocystis carinii was present in both areas and was the only organism found in the tissues examined. A third case presented with the more common radiographic appearance but also had a granulomatous histology. We conclude that P carinii pneumonia should be considered in the differential diagnosis of pulmonary nodules in immunocompromised patients and that pathologists should be aware of the possibility of a granulomatous reaction to this organism.