Ultrastructure of Cryptococcus neoformans.

The ultrastructure of C. neoformans was studied in two cases of cutaneous cryptococcosis. Extracellular and intracellular fungi were observed. Their capsules and clear zones were thick and distinct, but their cytoplasmic organelles were not obvious. In macrophages, a few stages of fungal degeneration could be observed. It could not be ascertained whether the changes were caused by anti-fungal drugs or by an influence by host macrophages. The ultrastructure of the yeast cells in vitro appeared to be that of degenerated cells because of a long culture period.