Hyponatremia as the presenting manifestation of Sheehan’s syndrome in elderly patients

Abstract

Hyponatremia is not a disease in itself, but a manifestation of a variety of disorders and side-effects of diuretics; alternatively, it may be the only manifestation of hypopituitarism or hypothyroidism. In our experience, diagnosis of hypopituitarism in hyponatremic patients is often overlooked, especially in the elderly. We report here data from five elderly multiparous women (mean age 69 yr; range 62-78 yr) with a past history of complicated delivery, in whom initial symptoms were due to hyponatremia (serum sodium less than 128 mEq/L) who went undiagnosed and untreated for a long time (up to 42 years) after the initial event. Initial hormonal levels indicated hypopituitarism, and magnetic resonance imaging led to diagnosis of empty sella in all patients, so that they were diagnosed as suffering from Sheehan's syndrome (SS). The occurrence of sodium and water disorders associated with SS depends on the degree of pituitary damage, time of onset since the initial pituitary insult, and concurrent medical conditions which also play a role in sodium and water balance. In these patients, clinical condition and hyponatremia improved rapidly after glucocorticoid substitution. L-thyroxine was appropriately substituted subsequently. We suggest that, especially in elderly patients, much more attention should be paid to patients' past history. Early recognition of severe hyponatremia due to hypopituitarism with adrenal insufficiency is critical, and treatment with hydrocortisone results in safe and improved quality of life.