Disseminated Fusarium infection in an immunocompromised host

A 42-year-old white man with acute myelomonocytic leukemia (AML) was admitted to the hospital for inductive chemotherapy. Four days after developing neutropenia, he developed fever, pain, and swelling of the third left toe. On examination, the foot was erythematous, swollen, and tender with onychomycosis and early gangrene of the toe. Examination of the eyes and heart were normal. Empiric treatment with vancomycin, piperacillin, cefetazidime, and fluconazole was started for presumed cellulitis. Despite the antibiotics, the toe required surgical drainage and distal partial amputation. Cultures from the blood and toe grew Fusarium spp. in 48 hours. Amphotericin B was started and fluconazole discontinued. In addition, he also developed multiple painful erythematous lesions with central necrotic areas over the rest of his body; these lesions also grew Fusarium. These lesions were not biopsied. The exit site of the Hickman catheter also became infected and on culture grew Fusarium. A computerized tomography (CT) scan of the abdomen was normal. The minimal inhibitory concentration (MIC) of amphotericin B at 48 and 72 hours was 4 μg per mL. The minimal fungicidal concentration (MFC) of amphotericin B at 48 and 72 hours was 4 μg per mL. Antifungal resistance was defined as > 1.56 μg per mL for amphotericin B and > 8 μg per mL for itraconazole. Amphotericin B treatment was continued for approximately 3 weeks with resolution of the lesions and the fungemia. On readmission, 4 weeks later for chemotherapy, he was placed on alternate-day amphotericin B. Monitoring of the blood levels was also started prior to discharge and continued for a total of 4 weeks. The patient remained well 8 weeks after discharge.