SAT-475 Two for One: A Case of Dual Cortisol and Aldosterone Secretion from an Adrenal Incidentaloma

Abstract Disclosure: L.H. Rosoph: None. N. Cazac: None. S. Rosoph: None. M. Shah: None. Adrenal incidentalomas are relatively prevalent, affecting 1-8% of the general population. Although the majority of adenomas are non-functioning, a small percentage secrete a single hormone. Dual-secreting adenomas, particularly those producing both aldosterone and cortisol, are rare and pose unique diagnostic and therapeutic challenges. This report describes a case of a dual aldosterone and cortisol secreting adrenal adenoma. A 41-year-old female with history of hypertension and ovarian and endometrial cancer was noted to have a 2.2 cm left adrenal incidentaloma on abdominopelvic CT for cancer surveillance. Initial endocrine evaluation including metanephrines, renin, aldosterone and 24-hour urinary cortisol was unremarkable. Repeat imaging in one year showed interval nodule growth to 2.9 cm. Urinary cortisol was found to be elevated at 106 (N: <45 mcg/day). Subsequent testing showed low DHEAS 8.8 μg/dL (N: 60.9-337 ug/dL) and suppressed ACTH (< 3 pg/mL, N: 7.2-63.3 pg/mL). Hypercortisolism was confirmed by low dose dexamethasone suppression test (cortisol level: 19.9 ug/dL, N: 6.0-18.4 ug/dL) and elevated midnight salivary cortisol levels (0.26 and 0.28 mcg/dL, N: < or = 0.09mcg/dL). Patient’s hypertension was difficult to control despite adherence to medication therefore further work up was completed revealing hyperaldosteronism given the aldosterone-to-renin ratio (ARR) of 22.2 ng/dL per ng/mL/h (N: < 20 ng/dL per ng/mL/hour). Adrenal venous sampling (AVS) demonstrated left-sided cortisol lateralization, however there was no evidence of aldosterone lateralization. The patient underwent laparoscopic adrenalectomy, with pathology confirming an adrenocortical adenoma. Postoperatively, ACTH levels slightly up trended, aldosterone-to-renin ratio normalized, oral glucocorticoids were tapered, and antihypertensive medications were discontinued. Dual aldosterone and cortisol secretion by a single adenoma is rare, with prevalence ranging from 5.3% to 21% among primary aldosteronism patients. This case highlights the diagnostic challenges of dual-secreting adrenal adenomas, particularly those producing both aldosterone and cortisol. Adrenal venous sampling plays a crucial role in lateralizing hormone production, guiding surgical management. However, AVS in the context of elevated cortisol levels makes the results difficult to interpret. As the value of AVS interpretation may be skewed, comprehensive endocrine evaluation is pivotal in the diagnosis and management of dual-secreting adrenal adenomas. Presentation: Saturday, July 12, 2025