Abstract
Hypernatremia dehydration in infancy is a medical emergency, which constitutes a potential threat to life. Diagnosis is quite often difficult and the fluid deficit is commonly underestimated. This happens because the intra-cellular fluid comes into the extracellular compartment due to hypertonicity. Complications are frequent and occur not only from the primary process of hypernatremia and loss of water, but more often because of rapid re-hydration. Overzealous treatment is as dangerous as delayed or sub-optimal treatment. The dramatic drop in serum sodium concentration leads to rebound cerebral oedema with resultant seizures and neurological complications. The mortality in acute cases in infants can be as high as 70%. Here we report a 5-month-old baby with severe hypovolemic hypernatremia dehydration and seizures due to rotavirus gastroenteritis and usage of formula milk and improperly diluted oral rehydration solution. The infant was ventilated and successfully re-hydrated with slow sodium correction and ultimately discharged without any neurological deficit. The clinical presentation and complications of hypernatremia are reviewed, and the essentials of management are discussed.

Key words: Cerebral edema, hypovolemia, hypertonicity, seizures.