Endocrine Abstracts

Background: Primary aldosteronism (PA) is a group of disorders characterized with inappropriately high adrenal aldosterone production, suppressed renin and hypertension. Prevalence of PA is approximately 5-10% in people with hypertension and up to 20-50% in those with resistant hypertension. PA is associated with increased cardiovascular and cerebrovascular morbidity and mortality rates compared with patients with essential hypertension when matched with age, sex and blood pressure. PA is commonly caused by an adrenal adenoma, unilateral or bilateral adrenal hyperplasia (BAH), or in rare cases adrenal carcinoma or inherited conditions of familial hyperaldosteronism. The cause of PA dictates the optimal treatment strategy- curative surgery (unilateral adrenalectomy) or mineralocorticoid receptor blockade. Corticotropin (ACTH)-independent hypercortisolism is relatively rare condition, diagnosed in <5% of patients with adrenal tumors or hyperplasia, while mild autonomous cortisol secretion (MACS) is common, affecting up to 50% of patients with unilateral adrenal adenomas. ACTH independent hypercortisolism can present with overt features of Cushing Syndrome (CS) or as MACS. Laparoscopic adrenalectomy is the treatment of choice.

Case presentation: We present a case of a 45 year old man with 10 year history of hypertension and spontaneous hypokalemia first documented 5 years ago. He was treated with Perindopril, Amlodipine, Indapamide, Nebivolol and potassium supplements. Laboratory workup planned at our clinic confirmed the diagnosis of primary aldosteronism. Adrenal CT revealed 14 mm left adrenal adenoma (-20 HU). Further evaluation with dexamethasone suppression test, ACTH and DHEA-S confirmed MACS. Considering the cosecretion of cortisol with aldosterone, adrenal venous sampling (AVS) was no longer required and the patient was advised about unilateral adrenalectomy.

Conclusion: In conclusion, in patients with large aldosterone-producing adenomas, the possibility of MACS should be evaluated as the identification of aldosterone and cortisol co-secreting neoplasms will require specific approach.

References: 1. Young WF Jr. Diagnosis and treatment of primary aldosteronism: practical clinical perspectives. J Intern Med. 2019;285(2):126-148.

2. Funder JW, Carey RM, Mantero F, et al. The Management of Primary Aldosteronism: Case Detection, Diagnosis, and Treatment: An Endocrine Society Clinical Practice Guideline. J Clin Endocrinol Metab. 2016;101(5):1889-916.