Mucor circinelloides as a cause of invasive maxillofacial zygomycosis: an emerging dimorphic pathogen with reduced susceptibility to posaconazole.

A case of maxillofacial zygomycosis caused by Mucor circinelloides, identified by phenotypic and molecular methods and treated successfully with liposomal amphotericin B (AmBisome) and surgical debridement, is described. The isolate was resistant to posaconazole. This report underscores the importance of prior susceptibility testing of zygomycetes to guide therapy with the most effective antifungal agent for an improved prognosis.