[Inter-phase hyponatremia ‒ A case report of a three-phase response in antidiuretic hormone release following...

Introduction: electrolyte disorders are the most common complication following pituitary surgery, with hyponatremia occurring in up to 25 % of cases. The triphasic response of antidiuretic hormone is a rare entity characterized by a sequence of transient vasopressin deficiency secondary to damage of the neurohypophyseal axonal tracts, followed by a phase of syndrome of inappropriate antidiuretic hormone secretion (SIADH) due to the release of preformed vasopressin, and finally by permanent vasopressin deficiency secondary to neuronal gliosis. Case report: we present the case of a 34-year-old woman who underwent pituitary adenoma resection and subsequently developed this complication. Discussion: this case highlights the importance of close postoperative monitoring and early treatment to prevent potentially serious complications.