The renin-angiotensin-aldosterone system in primary and secondary hypertension.

Important advances have been made in understanding the role of the renin-angiotensin-aldosterone system in the pathogenesis and diagnosis of hypertensive disorders. Measurement of plasma renin activity (PRA) and aldosterone is very important in the assessment of secondary hypertension. Hypertensions with increased PRA include renovascular hypertension, some cases of unilateral and bilateral renal parenchymal disease, malignant hypertension, hypertension associated with oral contraceptive agents, and renin-secreting tumors. Hypertension with decreased PRA is observed in four recognized types of primary aldosteronism: adenoma, bilateral hyperplasia, indeterminate aldosteronism, and glucocorticoid-responsive aldosteronism. Other conditions with hypertension and depressed PRA include ACTH and DOC secreting tumors, primary hyperpituitarism, syndromes of 17-hydroxylase and 11-beta-hydroxylase deficiency. Liddle's syndrome, licorice abuse, exogenous administration of mineralocorticoids, and preeclampsia.