Methotrexate-Induced Neurotoxicity: An Uncommon Stroke Mimic

A 21-year-old man with a recent diagnosis of high-risk pre-B-cell acute lymphocytic leukemia (ALL) presented with acute onset of aphasia. He had been on chemotherapy for 6 weeks and his regimen included intrathecal methotrexate (MTX) for central nervous system prophylaxis. The last 2 administrations were 1 and 9 days before presentation. Examination showed nonfluent aphasia without other deficits. Noncontrast computed tomography of the head was normal. Intravenous tissue plasminogen activator was not administered due to rapidly improving symptoms. Magnetic resonance imaging (MRI) of the brain showed multiple areas of restricted diffusion involving the subcortical white matter (Figure 1A and B) and splenium of the corpus callosum (Figure 1C and D). He returned to his baseline within 24 hours of the onset. Intrathecal methotrexate was discontinued after this episode