Histoplasmosis and Ajellomyces (Histoplasma)
capsulatum
Histoplasma capsulatum and Ajellomyces casulatus: in vitro | |||
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Holoblastic macroconidia at 25°C | Hypha and tuberculate macroconidia | Yeast cells at 37°C | ||||
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Typical older white mold colony at 25°C
Older = after many subcultures |
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H. capsulatum: In tissue | |||
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In liver | ||||||
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mΦ with many yeast cells from acute pulmonary case | ||||||
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H + E; yeast cells in phagocyte yeast cell shrunk from cell wall looks like a capsule | ||||||
Histoplasmosis: | Residual lesions | ||
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Residual calcified lesions in lung | Lesions (calcified) in spleen from previous acute histoplasmosis (0.2-0.4 cm in diameter) | |||||
Cutaneous lesions: | |||
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From dissemination | From dissemination | From dissemination | ||||
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Primary lesion from lab accident | ||||||
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