DQ stain, high power:
Extracellular yeast form with negatively staining, double contoured cell wall
The size of yeast is larger than red cells and comparable to lymphocyte nuclei
Pap stain, high power:
Yeast form with broad based budding and thick double contoured cell wall
Pap stain, high power:
Extracellular yeast forms with negatively staining thick double contoured cell wall
GMS stain, high power:
Broad based budding yeast of relatively similar sizes
Features
• Bronchioloalveolar lavage or washing
• Lung, skin, bone FNA
Blastomyces dermatitidis
Predominant form: Yeast
Size: 1-3x the size of lymphocyte nucleus or background RBC (8 • 21 µm)
Location: Predominantly extracellular
Features:
– Negative staining cell wall on DQ stain
– Thick, double-contoured cell wall
– Broad based budding