Hyponatraemia after orthopaedic surgery - a case of pituitary apoplexy.

We describe a case of profound hyponatraemia in a postoperative patient after total hip replacement caused by corticosteroid insufficiency due to a non-functioning pituitary macroadenoma diagnosed by dynamic endocrine tests and radiological imaging. Adopting a multidisciplinary approach, successful diagnosis and management lead to a complete recovery without any long-term sequelae.