Hyperaldosteronism

Excerpt

Aldosterone is a mineralocorticoid hormone that promotes sodium (salt) and water (fluid) retention, ultimately raising blood pressure. Aldosterone also increases urinary potassium excretion, which can sometimes lead to hypokalemia. Aldosterone is secreted by the zona glomerulosa, which is the outermost layer of the adrenal cortex. The production of this hormone is primarily regulated by angiotensin II, serum potassium, and adrenocorticotropic hormone (ACTH) levels. Please see StatPearls' companion resources, "Physiology, Aldosterone" and "Primary Hyperaldosteronism," for more information.

Hyperaldosteronism refers to the excess production of aldosterone. Patients typically present with hypertension initially that ranges from mild to severe and often resists medical treatment. Underlying hyperaldosteronism, causing the hypertension, often goes undiagnosed. Please see StatPearls' companion resource, "Primary Hyperaldosteronism," for more information.

Hyperaldosteronism may be classified as either primary or secondary. Although both forms present with similar clinical features, they are distinguished through laboratory testing and other diagnostic studies. Primary hyperaldosteronism is characterized by inappropriate autonomous hypersecretion of aldosterone by the adrenal glands, resulting in low plasma renin concentrations (PRCs; typically <1 ng/mL/h) and elevated serum aldosterone levels (usually >20 ng/dL). In contrast, secondary hyperaldosteronism arises from increased renin production and activity, often due to underlying conditions (see "Secondary Hyperaldosteronism" in the Etiology section below). Please see StatPearls' companion resources, "Physiology, Aldosterone" for more information.

The initial definitive laboratory tests for diagnosing hyperaldosteronism include serum aldosterone levels, PRC, plasma renin activity (PRA), and the aldosterone-to-renin ratio. Patients with hyperaldosteronism—particularly women—often face significant diagnostic delays, with more than one-third of patients waiting over 5 years to receive a correct diagnosis. Please see StatPearls' companion resource, "Primary Hyperaldosteronism," for more information.

Routine screening for hyperaldosteronism (defined by a serum aldosterone level >20 ng/dL or an aldosterone-to-renin ratio >20:1) is recommended for all patients newly diagnosed with hypertension. Screening is essential for individuals with an adrenal nodule, a family history of hyperaldosteronism, early-onset hypertension or stroke (before age 40), hypokalemia, the need for four or more antihypertensive medications, obstructive sleep apnea, atrial fibrillation, age younger than 35, or resistance to treatment with three standard antihypertensive agents.

Understanding the diagnosis and differentiation of hyperaldosteronism is crucial for effective management—whether surgical for unilateral primary hyperaldosteronism or medical for bilateral adrenal disease and secondary hyperaldosteronism.