Cushing's syndrome due to ACTH-secreting pheochromocytoma

Ectopic secretion of adrenocorticotropic hormone (ACTH) is an infrequent cause of Cushing's syndrome. We report a case of ectopic ACTH syndrome caused by a pheochromocytoma. A 53-year-old female with clinical features of Cushing s syndrome presented with serious recurrent hypertensive crisis. Endocrinological investigation confirmed the diagnosis of ectopic ACTH production and revealed markedly elevated urinary catecholamines leading to the diagnosis of pheochromocytoma. Abdominal computerized tomography (CT) scan showed a 3.5 cm left adrenal mass and a nodular hypertrophic right adrenal gland. Bilateral selective adrenal vein catheterization suggested bilateral pheochromocytoma. After treatment with phenoxybenzamine, bilateral adrenalectomy was performed and resulted in remission of Cushing's syndrome and hypertensive crisis. In addition, this article provides a short guideline for endocrine testing if Cushing's disease or pheochromocytoma is suspected. However, the most important message of this article is to think of them.