Isolated peripheral neuropathy as an unusual presentation for an extramedullary relapse of acute leukemia

A 23-year-old man in remission from acute myeloblastic leukemia after allogeneic peripheral blood stem cell transplantation developed peripheral neuropathy presenting as sciatic and peroneal nerve deficits. Electrophysiological tests localized the lesions to the left sciatic and common peroneal nerve. Magnetic resonance imaging revealed nerve thickening and enhancement, while a positron emission tomography-computed tomography scan demonstrated increased fluorodeoxyglucose uptake tracking along the nerve, suggesting peripheral nerve infiltration. This report demonstrates an unusual presentation of acute leukemia relapse presenting as focal neuropathy