RESUMEN
Key Clinical Message: Marchiafava-Bignami disease, a rare condition often associated with alcoholism, shows myelin degeneration with tissue necrosis specifically in the corpus callosum. Urgent application of magnetic resonance imaging could lead to prompt diagnosis. Abstract: A 66-year-old male with habitual alcohol drink complained acute deterioration of left-side muscle weakness as initial presentation. On the arrival, the patient was confused, with stable vital sign and unremarkable pyramidal sign. Although several potential diagnoses could be considered, brain computed tomography did not provide diagnostic information, and subsequently-performed magnetic resonance imaging revealed hyperintense lesions on T2-flair images in corpus callosum, suggesting MBD as clinical diagnosis. Prompt diagnosis enabled us to introduce thiamine administration with subsequent favorable neurological outcome.