Asymptomatic Extrapontine Myelinolysis in Diabetic Woman

ABSTRACT

Osmotic myelinolysis syndrome in central nervous system is classified into central pontine myelinolysis(CPM) and extrapontine myelinolysis(EPM). The former can cause a spastic quadriplegia, pseudobulbar palsy, and varying degree of mental disorder, but the latter a movement disorder(tremor, dystonia, parkinsonism, and chorea, etc), behavior change(mood instability, personality change, agitated delirium, and disinhibition, etc), and cognitive dysfunction. Although a few cases of asymptomatic CPM have been reported, asymptomatic EPM were rare. A 67-year-old woman with diabetes mellitus and old cerebral infarction has suffered from the common bile duct stone. She had hyponatremia(Na=126mEq/L) on admission and was corrected rapidly. Incidental findings of her brain MRI showed EPM. We experienced a case of bilateral middle cerebellar peduncle myelinolysis incidentally without neurological presentations and report a rare case of asymptomatic EPM recoverd in diabetic woman after rapid correction of hyponatremia.