SUN-396 Subclinical Cushing's Syndrome: Should We Treat?

Abstract

Background: Subclinical (mild) Cushing’s syndrome (SCS) is a common finding in incidental adrenal masses. Recent studies have shown there is increased morbidity and mortality with SCS. We present two cases that illustrate the importance of aggressive treatment of SCS. Clinical Case: A 66-yr-old female with multiple sclerosis and HTN presented to the ER with a 3-week history of hypertensive paroxysms >200/110. HTN previously has been well controlled with metoprolol and olmesartan. Evaluation for pheochromocytoma was negative. ACTH was <5 pg/mL, AM cortisol 14.6 mcg/dL, 24-hr-urine cortisol 108.4 mcg/d (RR <50), and 1 mg dexamethasone suppression test showed plasma cortisol 1.9 mcg/dL (RR <1.8). Patient was maintained on Toprol XL, amlodipine, amiloride, clonidine patch, and clonidine tablets. She continued to experience hypertensive paroxysms in addition to fatigue, hypersomnolence, proximal muscle weakness and developed pre-diabetes (HbA1c 6.1%). CT abdomen showed left adrenal thickening; 8 AM cortisol 23.4 mcg/dL (RR 6-18.4) and 11 pm salivary cortisol 0.145 mcg/d (RR <0.112). Mifepristone 300 mg QD and spironolactone 50 mg QD were initiated. Within 2 months, patient had resolution of hypertensive swings, was off clonidine, had a 25-50% improvement in muscle strength, and HbA1c 5.9%. Clinical Case: A 67-yr-old male with coronary disease and HTN presented with a BP of 240/130. Work up revealed left adrenal mass of 1.5 x 2.9 x 1.4cm. Endocrine work up was negative except for 24-hr-urine cortisol 100 mcg/day (RR <50). Patient maintained on 4 antihypertensive medications. He continued to have borderline HTN, weight gain, and developed pre-diabetes (FBG 116). CT scan at 6 months showed decreased L adrenal adenoma of 1.7 cm. Two years after initial presentation, 1 mg dexamethasone test showed AM cortisol 1.9 mcg/dL (RR <1.8), 11 pm salivary cortisol x2 negative, and repeat 24-hour urine cortisol 58 mcg/d (RR <50). Physical exam was negative for Cushingoid features. Patient was pretreated with mifepristone and underwent L adrenalectomy. Pathology was consistent with nodular adrenal hyperplasia with positive ACTH staining. Six months following surgery, improved blood pressure and glycemic control were noted allowing medication dose reduction. Discussion: It is important to recognize that patients with adrenal SCS are at increased risk for metabolic disease, cardiovascular incidents, and mortality. Patients should be monitored closely, and treatment can result in improved metabolic parameters and quality of life. Reference: Di Dalmazi, G., et al. (2014). Cardiovascular events and mortality in patients with adrenal incidentalomas that are either non-secreting or associated with intermediate phenotype or subclinical Cusing’s syndrome: 15-year retrospective study. The Lancet Diabetes & Endocrinology, Vol 2, Issue 5, 396-405.