Comparison of active renin concentration and plasma renin activity for the diagnosis of primary hyperaldosteronism in patients with an adrenal mass

Abstract

Objective: Plasma aldosterone concentration (PAC) to plasma renin activity (PRA) ratio is an established screening test for primary hyperaldosteronism. Due to the increased recognition of adrenal incidentalomas, reliable parameters are required. Determination of active renin concentration (ARC) in contrast to PRA offers advantages with regard to processing and standardization. The present study compared PRA and ARC under random conditions to establish thresholds for the diagnosis of primary hyperaldosteronism. Design and methods: Fifty patients with various adrenal tumors, including ten patients with aldosterone-secreting adrenal adenomas, as well as ten hypertensive patients and 23 normotensive volunteers were studied. PAC and PRA were measured by radioimmunoassay. ARC was determined by an immunoluminometric assay. Results: Receiver operating curve (ROC) analysis suggested a PAC to ARC ratio threshold of 90 ((ng/l)/(ng/l)) (sensitivity 100%, specificity 98.6%) and a ratio threshold of 62 by additional consideration of PAC $200 ng/l (sensitivity 100%, specificity 100%) for the diagnosis of aldosterone-secreting adrenal adenomas. Conclusions: A PAC to ARC ratio of $62 in patients with PAC levels $200 ng/l is a reliable screening method for primary hyperaldosteronism in patients with an aldosterone-producing adenoma under random conditions. Because of its advantages with regard to probe processing and its independence from endogenous angiotensinogen levels, ARC may be preferred to PRA.European Journal of Endocrinology 150 517-523

Prospective validation of an automated chemiluminescence-based assay of renin and aldosterone for the work-up of arterial hypertension

“…Accordingly, the replacement of the PRA with the chemi luminescent renin assay has rapidly occurred at many centers in spite of lack of any proof for superiority of the former over the latter in terms of diagnostic accuracy. The available studies mostly investigated the correlation of DRC with DRA [6][7][8][9][10][11]; only one retrospective study vali dated a chemiluminescent assay in PA patients, but did not compare the ARR CL , with the ARR RIA [12].…”

“…Several studies have evaluated chemiluminescent assays for measuring the plasma concentration of active renin (DRC) and aldosterone in hypertensive patients [6][7][8][9][10][11]. These studies, albeit showing that compared to the radioimmunometric methods the DRC assay allowed saving labor time and costs, overall had limitations in that most of them were designed to compare PRA to DRC [6,[8][9][10][11][12], rather than to test the diagnostic accuracy of the aldosteronerenin ratio (ARR) based on DRC (ARR CL ) and the PRAbased ARR (ARR RIA ), for identifying the sub types of primary aldosteronism that can be diagnosed conclusively.…”

Pharmacodynamic and Pharmacokinetic Characterization of the Aldosterone Synthase Inhibitor FAD286 in Two Rodent Models of Hyperaldosteronism: Comparison with the 11β-Hydroxylase Inhibitor Metyrapone

“…We sought to increase PAC to the middle to upper range (1-5 nM ϭ 360-1800 pg/ml) reported in patients with primary hyperaldosteronism (Phillips et al, 2000;Perschel et al, 2004;Unger et al, 2004). We initially explored a low-sodium diet, dietary potassium supplementation, diuretic/natriuretic treatment, or combinations thereof to amplify endogenous aldosterone.…”

“…These PACs represent the middle to upper range reported in patients with primary aldosteronism (Phillips et al, 2000;Perschel et al, 2004;Unger et al, 2004). Rats with baseline PAC values outside this range were excluded from analyses (see Results).…”

Indicators of mineralocorticoid excess in the evaluation of primary aldosteronism

“…14,17 The good accuracy of ARR is confirmed by other studies, in which plasma renin concentration was used with 1 ng l À1 as lower detection limit of the laboratory assay. 37 The same principle was applied for A UR /R ratio. Multiplying the ratio with A UR or A UR 2 , the AUC increased, but the specificity decreased gradually at constant sensitivity.…”