A Case of Acute Adrenal Insufficiency: A Rare but Possible Cause of Hypercalcemia.

A 30-year-old woman presented with a 15-day history of epigastric pain, nausea, vomiting, asthenia, and weight loss. On admission, hypercalcemia was reported with a negative etiologic workup (including no primary hyperparathyroidism, malignancy, or vitamin D toxicity). Fluid replacement did not improve her hypercalcemia. We performed a blood ionogram and assessed the adrenocortical function, which showed that her serum cortisol was decreased, her adrenocorticotropic hormone (ACTH) was elevated, and anti-21 hydroxylase antibodies were positive. We established the diagnosis of autoimmune primary acute adrenal insufficiency. The patient was treated with hydrocortisone. Shortly after initiating the treatment, her serum calcium levels returned to normal and her symptoms improved. This case report highlights the fact that even though adrenal insufficiency is an uncommon etiology of hypercalcemia, it should not be totally ignored, especially since hypercalcemia can sometimes be indicative of adrenal impairment.