Reversible Leukoencephalopathy Due to Cobalamin Deficiency After Subtotal Thyroidectomy for Graves' Thyrotoxicosis

We report a woman aged 37 years who showed rapid deterioration of psychomotor functions 6 months after a subtotal thyroidectomy for Graves' thyrotoxicosis. In addition to cobalamin deficiency, we observed pathologic changes in the brain tissue in accordance with a white matter disorder on brain imaging. The neurologic deficits and leukoencephalopathic changes in brain imaging responded to cobalamin replacement and returned to normal 6 months after treatment. The relationship between thyroid dysfunction and cobalamin levels in maintaining white matter is briefly reviewed.