The following is a summary of “Screening Cutoff Values for the Detection of Aldosterone-Producing Adenoma by LC-MS/MS and a Novel Noncompetitive CLEIA,” published in the June 2024 issue of Endocrinology by Ono, et al.

Detecting surgically treatable aldosterone-producing adenoma (APA) in hypertensive patients is crucial in clinical practice. While liquid chromatography-tandem mass spectrometry (LC-MS/MS) is the gold standard for measuring plasma aldosterone concentration (PAC), its expense and requirement for specialized expertise pose challenges. A newly developed noncompetitive CLEIA (NC-CLEIA) for PAC measurement offers rapid results within 30 minutes, presenting a potential alternative to LC-MS/MS. For a study, researchers sought to validate NC-CLEIA PAC measurements by comparing them with LC-MS/MS measurements and establishing screening cutoffs for both methods to detect APA.

Retrospective PAC measurements were conducted using LC-MS/MS and NC-CLEIA in a cohort comprising 133 patients with APA, 100 with bilateral hyperaldosteronism, and 111 with essential hypertension. The accuracy of NC-CLEIA PAC measurements was assessed by comparing them with LC-MS/MS measurements, and cutoff values for detecting APA were determined.

Analysis revealed a significant correlation and equivalence between PAC values obtained by NC-CLEIA and LC-MS/MS (Passing-Bablok analysis: slope=0.962, intercept=-0.043, correlation coefficient=0.994). NC-CLEIA demonstrated smaller systemic errors than LC-MS/MS (Bland-Altman analysis: bias=-0.348 ng/dL, limits of agreement=-4.390 to 3.694 within a 95% CI). Receiver operating characteristic analysis showed similar cutoff values for aldosterone/renin activity ratio obtained by both methods, with high sensitivity and specificity for distinguishing APA from non-APA (LC-MS/MS: cutoff=31.2 ng/dL per ng/mL/hour, sensitivity=91.0%, specificity=75.4%; NC-CLEIA: cutoff=31.5 ng/dL per ng/mL/hour, sensitivity=90.2%, specificity=76.8%).

The novel NC-CLEIA for measuring PAC offered a clinically reliable alternative to LC-MS/MS for detecting surgically treatable APA among patients with hypertension, potentially streamlining diagnosis and treatment decisions.

Reference: academic.oup.com/jes/article/8/6/bvae080/7655430