CNS relapse of acute myelogenous leukemia masquerading as pseudotumor cerebri.

An 18-year-old man in remission from acute myelogenous leukemia 3 years after a bone marrow transplant presented with signs of pseudotumor cerebri, including headache, visual changes, and papilledema. He manifested elevated opening pressure on lumbar puncture and positive cytology, with a concurrent normal bone marrow aspirate and biopsy. He was diagnosed with an isolated central nervous system relapse of acute myeloid leukemia. Although the precise etiology remains elusive, this case demonstrates that pseudotumor cerebri must remain within the differential diagnosis after other complications are excluded, particularly in persons with underlying hematologic malignancies.