An elevation in the aldosterone with a markedly decreased plasma renin activity is evidence for primary hyperaldosteronism.


Patient Preparation: The patient should be kept supine prior to sample collection.


aldosterone-to-renin ratio =

= (plasma aldosterone) / (plasma renin activity)



• Primary aldosteronism is suspected if (1) the plasma aldosterone level is increased, (2) the plasma renin is decreased, and (3) the aldosterone-to-renin ratio is > 50.

• With exogenous or endogenous mineralocorticoids, hypervolemic hypertension and hypokalemia will be present and the plasma renin activity will be reduced, but aldosterone levels will also be depressed.



• False positive tests may occur, especially in patients taking beta-adrenergic blockers.

• Assays for plasma renin activity can be problematic.


To read more or access our algorithms and calculators, please log in or register.