Tissue Changes and Tissue Diagnosis in Cryptococcosis: A Study of 26 Cases

Abstract

Twenty-six human cases of cryptococcosis showed early gelatinous lesions and older granulomatous lesions. Gelatinous lesions consisted of masses of organisms with little inflammatory response, whereas the granulomatous lesions were composed chiefly of giant cells, macrophages, lymphocytes and fibrosis. "Caseous" necrosis, observed in only 5 of the cases, consisted of necrotic masses of organisms. Small cavities occurred in 2 of the 5 cases. Neutrophils were numerous in 5 cases and minute abscesses were found in one. The authors conclude that cryptococcosis is usually a nonsuppurative disease. Tissue diagnosis of cryptococcosis was made on the basis of presence of gelatinous capsules and budding in organisms of appropriate size. The periodic acid-Schiff, the Gridley, and the Gram stains were all helpful in demonstrating the organisms, but hematoxylin and eosin was an adequate method. Although cultural methods should always be performed, the diagnosis of cryptococcosis can be made without a positive culture.