[Osmotic demyelination syndrome complicating the quick correction of a severe hyponatremia associated with hypokalemia]. / Syndrome de démyélinisation osmotique compliquant la correction rapide d'une hyponatrémie sévère associée à une hypokaliémie.

Osmotic demyelination syndrome is characterized by the loss of myelin in the center of the basis pontis and other areas of the central nervous system. We report a case of osmotic demyelination syndrome in a 55-year-old female, with a past medical history of arterial hypertension and multi-level cervical spondylosis, hospitalized for acute altered mental status complicating an array of acute gastroenteritis, the patient was afebrile. The course was marked by neurologic aggravation with confusion, aphasia, tetraplegia and osteo-tendinous areflexia. Initial cerebral magnetic resonance imaging did not show any specific abnormalities. The diagnosis of Central pontine myelinolysis and extrapontine myelinolysis was confirmed by a cerebral magnetic resonance imaging done after 20 days of the first. The rapid correction of hyponatremia was the main cause of this syndrome, without neglecting the very likely role of the associated hypokalemia. The evolution of centropontine myelinolysis (CPM) and extrapontine myelinolysis (EPM) is variable. The treatment is primarily preventive based on the careful correction of severe hyponatraemia and contributing factors.