High-probability features of primary aldosteronism may obviate the need for confirmatory testing without increasing false-positive diagnoses.

This retrospective review examined all primary aldosteronism (PA) adrenal vein sampling (AVS), diagnoses, and outcomes from an endocrine hypertension unit where confirmatory testing was abandoned in 2005 to determine the potential rate of false-positive diagnoses. Patients with outcome-verified PA (surgical patients) were compared with patients with high-probability PA (nonsurgical but high aldosterone-renin ratio, imaging abnormalities, and/or hypokalemia) or possible PA (nonsurgical, no features besides mild elevation of aldosterone-renin ratio, a potential false diagnosis of PA). Of 83 patients, 58% had unilateral PA and 42% had bilateral aldosteronism. Less than 3% of the cohort showed bilateral aldosteronism without hypokalemia or computed tomographic findings, potentially representing the false-positive PA diagnosis rate with omission of confirmatory tests in this population. In a hypertension referral unit enriched in high-probability PA cases and where high AVS success is achieved, omission of a PA confirmatory test yields a high rate of surgical diagnosis with few potential false-positive diagnoses.