Enfermedades de la secreción de aldosterona

Abstract

Hyper- and hypoaldosteronism are caused by an excessive or insufficient adrenal secretion of aldosterone, respectively. Idiopathic bilateral hyperplasia and aldosterone-producing adenoma are the commonest causes of primary hyperaldosteronism. Primary hyperaldosteronism is characterized by hypertension, hypokalemia and metabolic alkalosis; in turn, hypoaldosteronism presents hyperkalemia and metabolic acidosis. The aldosterone/plasma renin activity ratio (ARR) is routinely used as a screening test of primary hyperaldosteronism. Functional tests are recommended if ARR is high (salt-loading, intravenous or oral, and fludrocortisone or captopril suppression). Once diagnostic is confirmed, imaging studies (abdominal computed tomography —CT—) and adrenal vein catheterization (in patients for surgery) have to be performed. Plasma levels of aldosterone and renin activity have to be determined by stimulatory functional tests (response to posture and volume depletion tests). Unilateral laparoscopic adrenalectomy is recommended in primary hyperaldosteronism caused by unilateral hyperplasia or adenoma; mineralocorticoid (spironolactone) receptor antagonists are the first-choice treatment for bilateral cases and in patients considered unfit for surgery. Potassium restriction and mineralocorticoid replacement therapy with fludrocortisone is the treatment of hypoaldosteronism.