Essential hypernatraemia in a young dog

A five-month-old great dane puppy was presented with hypernatraemia and clinical signs of vomiting, depression, disorientation, hyperi-rritability and adipsia. A diagnosis of essential hypernatraemia was based on the observation of adipsia, severe hypernatraemia, ability to concentrate urine only when hypovolaemic, normal serum aldosterone levels, normokalaemia and normotension. No abnormalities were found on histopathology of the neurocircuitry of the brain. This dog is compared with other reported cases of hypernatraemia in both dogs and humans.