Alveolar Damage in AIDS-Related Pneumocystis carinii Pneumonia

Pneumocystis carinii pneumonia is the most common and serious of the pulmonary complications of AIDS. Despite this, many basic aspects in the pathogenesis of HIV-associated P carinii pneumonia are unknown. We therefore undertook a light and electron microscopic study of transbronchial biopsy specimens to compare pathologic features of P carinii pneumonia and other HIV-related lung diseases. Thirty-seven consecutive HIV-infected patients undergoing a diagnostic bronchoscopy. P carinii pneumonia was characterized by an increase in inflammation, edema, exudate, fibrosis, type II pneumocyte proliferation, and cellular infiltration of the alveolar wall when compared with other lung diseases (all p