*Interpretive guideline: A plasma aldosterone concentration (PAC) > 10 ng/dL, plasma renin activity (PRA) < 1 ng/mL/hr, and PAC/PRA ratio > 20 are suggestive of primary aldosteronism (PA). Plasma renin and aldosterone were measured in the morning after the patient had been seated for 30 minutes. This evidence concerns the gene REN and primary aldosteronism.