Association of prolonged fever and hypernatremia: rare presentation of hypothalamic/third ventricle tumor in a toddler.

The authors describe a 2-year-old boy with a clinical presentation of prolonged fever of unknown origin and severe hypernatremia. This rare association was the result of a hypothalamic/third ventricle tumor. The lesion was removed and was found to be a low-grade neuronal tumor. After surgery, the child did generally well, but hypothalamic thermoregulatory and osmoregulatory functions were not restored. These presenting symptoms, their pathophysiology, and the implications for pediatric practice are discussed.