[Central pontine myelinolysis induced by hyperemesis gravidarum].

An 18-year-old woman in her first pregnancy with hyperemesis gravidarum, presented dehydration, without hyponatremia. She was confused with profound disorientation, apathy, and drowsiness. She presented upbeating nistagmus on upward gaze and gate ataxia recognised as Wernicke's encephalopathy. Laboratory tests demonstrated hypokalemia, hypernatremia and aminotransferase elevation. The serum osmolality was 319 mOsm/kg and the water deficiency 2.73 l. The patient developed weakness in the four limbs, with hypotonicity, absence of tendon reflexes and showed bilateral Babinski signs. A T2 weighted sagittal cranial-magnetic resonance imaging revealed a high signal within mid-pons suggesting central pontine myelinolysis. In this case we highlight the absence of hyponatremia. Furthermore, the central pontine myelinolysis was probably secondary to hypokalemia, hypernatremia and hyperosmolality.