Yeast Fungi

Cryptococcosis (Cryptococcus neoformans)

This H&E-stained section shows organisms, 4-7 µm in diameter (arrow). The inner circle separates the capsule from the organism. India ink is used to outline organisms in the CSF.

A mucicarmine stain that colors the polysaccharide capsule red is diagnostic. A narrow-necked budding form is indicated at the arrow.

Coccidioidomycosis (Coccidioides immitis)

This granuloma has a purulent center (many PMNs). Some of the multinucleated giant cells around the edge contain maturing sporangia (arrow indicates one).

This GMS stain shows a spherule (30-60 µm) releasing endospores (2-3 µm). The other forms are maturing sporangia. Only the spherule with endospores is diagnostic. Contiguous immature sporangia (arrow) resemble blastomyces.