Central pontine myelinolysis. Considerations on etiology, diagnosis, and treatment.

Pontine myelinolysis can be suspected clinically on the basis of the following criteria: (1) Electrolyte disturbance manifested mainly by hyponatremia; (2) progressive neurologic deficits resulting in a "locked-in" syndrome; (3) usually, but not necessarily, alcohol abuse; and (4) frequent iatrogenic precipitation of the syndrome by inappropriate rehydration of patients at risk. A major pathophysiologic mechanism for this disorder seems to be the anatomic grid structure of the base of the pons, which is more vulnerable to edema than the cerebral hemispheres. Treatment should be focused on rapid reversal of electrolyte imbalance and judicious use of dehydrating agents. Early diagnosis and treatment might reverse an otherwise malignant syndrome.