Central pontine myelinolysis: association with parenteral magnesium administration.

A 29-year-old woman with diabetes mellitus and nephrotic syndrome was given 30 g of magnesium sulfate over 14 hours after a cesarian section. Her serum magnesium level increased to 7.4 mg/dl. Five days later, she became quadriplegic with inability to speak or swallow. Cranial magnetic resonance imaging demonstrated central pontine myelinolysis (CPM). Initial serum sodium was not measured. Although CPM is usually associated with a rapid increase in serum osmolality, most patients who experience a rapid increase in serum osmolality do not develop the clinical syndrome of CPM. Consequently, additional factors may also be important in the pathogenesis of CPM. Parenteral magnesium administration may be a potential contributing factor in the pathogenesis of some cases of CPM.