The fungus can be isolated from soil, water and sewage.
Risk factors for human infection:
(1) significant immunosuppression, often an organ transplant
(2) environmental trauma with direct inoculation
An implicated episode of trauma may occur years prior to onset, suggesting that the organism can persist for a long period of time.
The fungus most often causes a subcutaneous nodule. Biopsy of a lesion shows septate fungal hyphae with the organism growing on chocolate agar.
The organism may respond to antifungal therapy (itraconazole, voriconazole, posaconazole, fluconazole, amphotericin B) but may also be resistant, requiring surgical excision.
