Acute disseminated encephalomyelitis (ADEM) after allogeneic bone marrow transplantation for acute myeloid leukemia.

Acute disseminated encephalomyelitis (ADEM) is a rare inflammatory demyelinating disease of the central nervous system. We describe here a patient who developed ADEM after allogeneic bone marrow transplantation (BMT). A 48-year-old woman with acute myeloid leukemia (M2) underwent allogeneic BMT from her HLA-identical sister. Cyclosporin for prophylaxis of acute graft-versus-host disease (GVHD) was discontinued from day 15 because of its toxicity. She was relatively well after the resolution of cytomegalovirus reactivation and chronic GVHD. Nine months after BMT, she suddenly developed diplopia, dysarthria, and gait disturbance. Computed tomography of the brain at that time revealed no abnormal findings. Leukemia recurrence was not revealed. The neurological symptoms were very mild without further deterioration. Her clinical course was carefully watched without therapy. Two weeks after onset, fluid attenuated inversion recovery magnetic resonance imaging (MRI) revealed multifocal abnormal high-signal intensity mainly in the white matter of the cerebrum as well as in the cerebellum and brainstem. Cerebrospinal fluid examination showed no abnormal findings. No laboratory findings suggested the presence of infectious agents. The typical MRI findings and an acute monophasic clinical course of this patient led to a diagnosis of ADEM. Twelve weeks after onset, the symptoms had almost resolved. Follow-up MRI showed a substantial improvement of the previous lesions without any new lesions. The symptoms had completely resolved 5 months after onset. This is a rare case of ADEM developing after allogeneic BMT.