Hyponatremia due to Secondary Adrenal Insufficiency Successfully Treated by Dexamethasone with Sodium Chloride

Final Diagnosis: Hyponatremia due to secondary adrenal insufficiency Symptoms: prolonged general fatigue and anorexia Medication: — Clinical Procedure: Successfully treated by dexamethasone with sodium chloride Specialty: Nephrology Objective: Rare co-existance of disease or pathology Background: Patients who were surgically treated for Cushing’s syndrome postoperatively surrender to “primary ” adrenal insufficiency. However, the preoperative over-secretion of cortisol or the postoperative administration of ex-cessive glucocorticoids can cause “secondary ” adrenal insufficiency, in which the prevalence of hyponatremia is usually lower than that of primary adrenal insufficiency. Case Report: A 60-year-old woman with a past medical history of Cushing’s syndrome developed hyponatremia with symp-toms of acute glucocorticoid deficiency, such as prolonged general fatigue and anorexia, after upper respirato-ry tract infection. A decrease in the serum cortisol level and the lack of increase in the ACTH level, despite the increased demand for cortisol, enabled a diagnosis of “secondary ” adrenal insufficiency. Although the initial fluid replacement therapy was not effective, co-administration of dexamethasone and sodium chloride quick