Gastrointestinal Zygomycosis Masquerading as Acute Appendicitis

Zygomycosis is a rare invasive opportunistic fungal infection that occurs in the setting of hematologic malignancies, chemotherapy-induced neutropenia, and immunosuppressive therapies. We report the first case of disseminated appendiceal zygomycosis due to Absidia spp. in a neutropenic patient who initially presented as acute appendicitis. A 63-year-old woman with acute myeloid leukemia presented as acute appendicitis while receiving induction chemotherapy and ultimately succumbed to overwhelming disseminated zygomycosis. Initial symptoms included loose stools and right lower abdominal pain unresponsive to broad-spectrum antibiotics. Clinical examination and cross-sectional imaging suggested acute appendicitis. The final diagnosis was established by histological evaluations of the ileocecectomy specimen, which showed angioinvasive fungal organisms within the necrotic appendiceal wall with characteristics typical of zygomycetes. Fungal cultures demonstrated Absidia spp. The patient was treated with amphotericin B but expired in the setting of fungal sepsis. A diagnosis of a fungal infection, including zygomycosis, should be considered in all chemotherapy-induced neutropenic patients who present with symptoms of acute appendicitis. A high index of clinical suspicion with prompt histologic and culture diagnosis of zygomycosis may reduce the high mortality and morbidity associated with zygomycosis of the gastrointestinal tract.