Severe Hyponatremia as an Uncommon Presenting Feature of Pituitary Macroadenoma.

: Hyponatremia is a common electrolyte disturbance, but less commonly utilized and require a thorough evaluation to unmask etiology. It has variety of causes and is rarely due to hypopituitarism. Hyponatremia is a very early complication of pituitary tumor. Here, we report a case, who presented to us with hyponatremia and eventually thorough work-up led us to a diagnosis of Non-functioning pituitary macroadenoma.