# Osmotic Demyelination Syndrome Associated With Severe Acute Hypernatremia Secondary to Poorly Controlled Central Diabetes Insipidus

## TL;DR

A rare case of osmotic demyelination syndrome caused by severe hypernatremia due to poorly managed central diabetes insipidus is reported, with successful treatment.

## Contribution

This paper presents a rare clinical case linking hypernatremia and osmotic demyelination syndrome in the context of central diabetes insipidus.

## Key findings

- Severe acute hypernatremia at 181 mEq/l was secondary to abrupt discontinuation of desmopressin.
- The patient developed centropontine and extrapontine myelinolysis.
- Reintroduction of desmopressin and correction of hypernatremia led to favorable clinical evolution.

## Abstract

Osmotic demyelination syndrome is a rare disorder caused by destruction of the myelin sheath, particularly in the pontine region, generally secondary to rapid osmotic variations. Osmotic demyelination syndrome due to hypernatremia is rarely described in the literature. The prognosis has improved thanks to a better understanding of its pathophysiology and advances in diagnosis and therapy. In this article, we report the case of centropontine and extrapontine myelinolysis associated with severe acute hypernatremia at 181 mEq/l secondary to abrupt discontinuation of desmopressin prescribed in the setting of central diabetic insipidus complicating pituitary surgery in a 58-year-old man. The evolution was favorable after reintroduction of desmopressin and correction of hypernatremia.