An Uncommon Case of Upper-Extremity Mucormycosis in a Patient With Acute Myeloid Leukemia.

Upper-extremity mucormycosis is a rare, life-threatening fungal infection mainly affecting immunocompromised patients. We report a case of a 30-year-old woman with acute myelogenous leukemia who developed this infection during her hospital stay. The culprit was Mucorales, a subgroup of Zygomycetes species known for fast-progressing, highly lethal infections. She presented with fever, chills, and a lesion on her left forearm that worsened despite initial broad-spectrum antibiotics. A punch biopsy confirmed the diagnosis, leading to antifungal therapy with isavuconazonium sulfate and later amphotericin B, combined with surgery. Timely intervention is critical because delayed treatment can result in severe complications and death. Early suspicion, histology, microscopy, and fungal cultures are vital for accurate diagnosis. Treatment primarily involves amphotericin B, whereas adjunctive therapies such as topical amphotericin B and hyperbaric oxygen show promise. This case underscores the importance of prompt medical and surgical action, enhancing early detection of mucormycosis in immunocompromised patients.