Large, broadly-based budding yeast cells characteristic of Blastomyces dermatitidis in a GMS-stained biopsy section from a human leg. Inhaled conidia of B. dermatitidis are phagocytosed by neutrophils and macrophages in alveoli. Some of these escape phagocytosis and transform into yeast phase rapidly. Having thick walls, these are resistant to phagocytosis and express glycoprotein, BAD-1, which is a virulence factor as well as an epitope. In lung tissue, they multiply and may disseminate through blood and lymphatics to other organs, including the skin, bone, genitourinary tract, and brain. The incubation period is 30 to 100 days, although infection can be asymptomatic.
Blastomycosis
Chromoblastomycosis
Actinomycosis
Basidiobolomycosis
Botryomycosis
Conidiobolomycosis
Talaromycosis
Dermatomycosis