Blastomyces dermatitidis and Blastomycosis
Gregory M. Gauthier
from: Human Pathogenic Fungi: Molecular Biology and Pathogenic Mechanisms (Edited by: Derek J. Sullivan and Gary P. Moran). Caister Academic Press, U.K. (2014)
The etiologic agent of blastomycosis, Blastomyces dermatitidis, belongs to a group of ascomycete fungi that exhibit thermal dimorphism. In the soil (22-25°C), these fungi grow as filamentous mold that produce infectious conidia. Following the disruption of soil by activities such as construction, aerosolized conidia and mold fragments are inhaled into the lungs of a host (37°C) and convert into pathogenic yeast. In the yeast form, B. dermatitidis is capable of evading immune defenses by altering the composition of the fungal cell wall and impairing the host's cytokine response. Approximately 25-40% of patients infected with B. dermatitidis develop disseminated disease, which frequently involves the skin or bone. Diagnosis of blastomycosis requires a high degree of clinical suspicion coupled with the use of culture and non-culture diagnostics. Treatment requires the use of polyene or azole antifungals read more ...