Endocrine Abstracts

Introduction: The clinical presentation of ectopic Cushing’s syndrome secondary to pheochromocytoma differs from the classic manifestations of these endocrinopathies separately. This cosecretion causes greater morbidity, requiring a complex preoperative preparation. We describe two clinical cases, a 46-year-old male with grade II overweight and a 65-year-old female with grade I obesity, both with a personal history of hypertension poorly controlled with 7 and 3 antihypertensive drugs respectively and new-onset diabetes, the first as hyperosmolar hyperglycemic state, classified as type 2 diabetes mellitus (DM) treated with non-insulin hypoglycemic agents and insulin with progressive worsening of glycemic control despite a weight loss of 27.3% and 16.5% in the last 3 months respectively. The first case was associated with axonal sensory polyneuropathy in the lower limbs with clinical suspicion of Guillain-Barré Syndrome under follow-up by Neurology, while the second case reported paroxysmal tachycardia. On physical examination both had lower limbs edema and muscular atrophy in the extremities, but without cushing phenotype. Blood tests from the first and second cases reported: glucose 161 mg/dl and 284 mg/dl (70-100), potassium 2.2mEq/l and 2.3mEq/l (3.5-5.5), HbA1c 8.2% and 8.6% (<6.5%), pH 7.52 and 7. 48 (7.35-7.45), bicarbonate 46mmol/l and 33mmol/l (22-29), urine cortisol 9582 mgg/24h and >11253mg/24h (0.1-180), Nugent’s test >75 mg/dl in both cases, ACTH 260pg/ml and 241pg/Ml (5-50), androgens, aldosterone, renin and normal ratios, metanephrine 2205 mg/24h and 1113 mg/24h (20-302), normetanephrine 1230 mgg/24h and normal (30-527) and methoxytyramine 1212 mg/24h and normal (103-434), respectively. Pituitary MRI was normal in both. In the first case, the thoraco-abdominal CT revealed multiple chronic dorso-lumbar vertebral fractures and left adrenal mass of 37 x 37mm compatible with pheochromocytoma, while the second case presented bilateral adrenal hypertrophy with right adrenal mass of 31 x 26mm compatible with pheochromocytoma. Given the clinical diagnosis of ectopic Cushing’s syndrome due to pheochromocytoma, unilateral adrenalectomy was decided after being treatment with fenoxybenzamine and doxazosin, respectively, and metyrapone in both cases. Patology reported pheochromocytoma with free resection borders, PASS score 9 and 2 respectively, with ACTH expression. Both developed post-surgical primary adrenal insufficiency. Currently, both present normo-cortisolims ascertained with Synacthen test and remission of DM. Blood pressure controlled with 3 hypotensors and none, respectively.

Conclusions: In our experience, ectopic ACTH-producing pheochromocytomas are characterized by the association of uncontrolled hypertension, hyperglycemia, metabolic alkalosis and severe hypokalemia. In these scenarios, pre-surgical preparation with steroidogenesis inhibitors to maintain homeostasis is just as much a priority as alpha-adrenergic blockade.