Reversible white matter lesions in a patient with fulminant hepatitis and acute renal failure

A 36-year-old man developed fulminant hepatitis and acute renal failure with profound hyponatremia (116 mEq/L). Emergent hemodialysis corrected the serum sodium to 136 mEq/L within 24 hours. He developed generalized convulsions 11 days later. Magnetic resonance imaging (MRI) revealed a single large symmetrical lesion in the pons and extensive white matter lesions in the bilateral occipital, temporal, parietal and right frontal regions. These lesions showed marked resolution as the patient recovered. Fulminant hepatitis and acute renal failure could induce extensive edema in the cerebral white matter. Therefore, not all MRI abnormalities in the white matter after correction of hyponatremia necessarily reflect myelinolysis.