Blastomyces dermatitidis is a dimorphic fungus with some characteristics similar to thoseof Histoplasma. Growth develops in the yeast phase in tissues and in cultures incubated at 37°C. The yeast cells are typically larger (8–15 mm) than those of H. capsulatum,with broad-based buds and a thick wall (Fig 49–3). The mold phase appears in culture at 25°C. Hyphae are septate and produce round to oval conidia sufficiently similar to the micro-conidia produced by H. capsulatum to cause confusion between the two in young cul-tures. Although older cultures may produce chlamydoconidia, B. dermatitidis produces no structure as distinctive as the tuberculate macroconidium of Histoplasma.
Copyright © 2018-2021 BrainKart.com; All Rights Reserved. (BS) Developed by Therithal info, Chennai.