Zygomycosis.

Zygomycosis is an invasive mycotic disease caused by fungi in the class Zygomycetes. Within this class, the most common species associated with infection include Absidia corymbifera, Apophysomyces elegans, Cunninghamella bertholletiae, Rhizomucor pusillus, Rhizopus microsporus var. rhizopodiformis, and Rhizopus arrhizus. These fungi all produce characteristic hyphal forms in tissue that are variable in width, produce haphazard branching, and lack septation. Although these fungi are ubiquitous in the environment, they are opportunists causing invasive disease in compromised hosts with a high mortality even when aggressive antifungal therapy and surgical intervention are utilized. Clinically, the disease most often affects the sinus with or without pulmonary involvement; direct extension from sinuses into cerebral tissue is not uncommon. This article describes the general clinical features of zygomycosis, with an emphasis on management in the setting of immunosuppression.