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, resulting in hypokalemia. It is secreted by the zona glomerulosa—the outermost layer of the adrenal cortex. Excess production of aldosterone is referred to as hyperaldosteronism. This condition typically presents initially as hypertension, which can range from mild to severe and resistant to treatment. Often, the underlying hyperaldosteronism responsible for the hypertension goes undiagnosed. Please see the companion StatPearls' reference resource, "Physiology, Aldosterone," for more information.

Hyperaldosteronism can be of primary or secondary origin. Although both forms present similarly, they are differentiated through laboratory testing and diagnostic studies. Primary hyperaldosteronism is characterized by low plasma renin concentrations, usually less than 1 ng/mL/h, and elevated serum aldosterone levels, typically more than 20 ng/dL, due to inappropriate autonomous hypersecretion of adrenal aldosterone. Secondary hyperaldosteronism results from excessive renin production and activity due to various conditions, including renal artery stenosis, left heart failure, liver failure with ascites, cor pulmonale, pregnancy, renin-secreting tumors, excessive licorice ingestion, renal tubular acidosis, nutcracker syndrome, kidney failure, and genetic conditions such as Bartter and Gitelman syndromes.

The initial definitive laboratory measurements to diagnose hyperaldosteronism include plasma renin concentration and activity, serum aldosterone levels, and the aldosterone-to-renin ratio. Patients with hyperaldosteronism, especially women, often experience significant diagnostic delays, with more than one-third of patients waiting over 5 years to receive a correct diagnosis. Please see the companion StatPearls' reference resource, "Primary Hyperaldosteronism," for more information.

Routine screening for hyperaldosteronism (serum aldosterone >20 ng/dL or an aldosterone-to-renin ratio >20:1) is recommended for all patients newly diagnosed with hypertension, particularly those unresponsive to standard antihypertensive medications. Understanding the diagnosis and differentiation of hyperaldosteronism is essential to determine the appropriate treatment, whether surgical for unilateral primary hyperaldosteronism or medical for bilateral adrenal disease and secondary hyperaldosteronism.