Mycology Organism Flashcards

This set of flashcards covers key mycology organisms, including their modes of transmission, diagnostic methods, microscopy characteristics, colony morphology, growth conditions, stains, and diseases they cause.

Histoplasma capsulatum

How you get it: Inhalation (bird/bat droppings). Diagnosis/Test: Urine antigen, biopsy, culture. Microscopy: Small intracellular yeast in macrophages. Colony morphology: White cottony mold at 25–30°C. Growth temp: Mold at 25–30°C; yeast at 37°C (dimorphic). Stain: GMS, PAS, Giemsa. Causes: Histoplasmosis.

Blastomyces dermatitidis

How you get it: Inhalation (soil). Diagnosis/Test: Culture, microscopy. Microscopy: Large yeast with broad-based budding. Colony morphology: Cottony white mold that darkens with age. Growth temp: Mold at 25–30°C; yeast at 37°C. Stain: GMS, PAS. Causes: Blastomycosis.

Coccidioides immitis/posadasii

How you get it: Inhalation (dust). Diagnosis/Test: Culture, serology. Microscopy: Large spherules with endospores. Colony morphology: White to gray cottony colonies. Growth temp: Mold at 25–30°C; spherules in tissue (37°C). Stain: GMS, PAS. Causes: Valley fever.

Paracoccidioides brasiliensis

How you get it: Inhalation. Diagnosis/Test: Microscopy, culture. Microscopy: Mariner’s wheel budding. Colony morphology: Mold colony (not commonly emphasized). Growth temp: Mold at 25°C; yeast at 37°C. Stain: GMS, PAS. Causes: Paracoccidioidomycosis.

Sporothrix schenckii

How you get it: Trauma (rose thorn). Diagnosis/Test: Culture, microscopy. Microscopy: Cigar-shaped yeast. Colony morphology: Moist wrinkled colonies. Growth temp: Mold at 25°C; yeast at 37°C. Stain: GMS, PAS. Causes: Sporotrichosis.