Endocrine Abstracts

JOINT2534

Introduction: Pheochromocytoma is a rare catecholamine-secreting tumor that arises from chromaffin cells in the adrenal medulla. Pheochromocytomas may rarely secrete adrenocorticotropic hormone (ACTH) or CRH (corticotropin-releasing hormone) and calcitonin in addition to catecholamines. Ectopic ACTH syndrome due to pheochromocytoma is a very rare disorder. These patients carry a significant risk of severe complications if not diagnosed and managed appropriately.

Case: A 53-year-old male was referred to our clinic with muscle weakness, weight loss, high blood pressure, headache, palpitations, and flushing. The patient had developed diabetes in the last month and was taking oral antidiabetic medication. The patient was normokalemic in her first evaluation and in her hormonal evaluation. The patient’s hormone levels showed that ACTH was 19.8 pg/ml, cortisol was 15.4 µg/dl, DHEA-SO4 was 89.51 µg/dl (34.5-568.9), 24-h urine cortisol was 46.69 µg (10-100), 1 mg dexamethasone suppression test was 11.1, 24-h urine metanephrine was 2719 µg, normetanephrine was 2693 µg, plasma metanephrine was 303 pg/ml, and normetanephrine was 935 pg/ml. The CT imaging of the patient’s abdomen revealed a 35x30 mm thick-walled, low-density, heterogeneous lesion in the right adrenal gland. During follow-up, the patient rapidly became hypokalemic, potassium replacement was administered, and spironolactone was started. Plasma cortisol level increased to 110 µg, ACTH level to 452 pg/ml and 24-h urine cortisol level increased to 3755 µg. We started the patient on 400 mg of fluconazole intravenously. During follow-up, the patient benefited somewhat from the treatment. The treatment brought the patient’s blood pressure and blood sugar under control. The patient was operated after appropriate surgical preparation. After the removal of a right adrenal pheochromocytoma, the patient’s elevated levels of serum and urine corticosteroids, plasma ACTH, plasma catecholamines, and urinary catecholamine metabolites decreased. Pathological examination revealed diffuse positive staining with ACTH in the pheochromocytoma area. The patient became normotensive after the operation. The patient, who was receiving basal-bolus insulin therapy, continued his diabetes treatment with oral antidiabetic.

Conclusion: Ectopic ACTH syndrome is very rare in patients with pheochromocytoma. These patients have a relatively rapid course, marked hypokalemia, diabetes mellitus or significant hypertension. The management of these patients is difficult, and there may be difficulties in obtaining therapeutic agents. Proper preoperative recognition and management can result in total cure.