Development of a New Chemiluminescent Enzyme Immunoassay Using a Two-Step Sandwich Method for Measuring Aldosterone Concentrations.

Yoshinori Ozeki,Mizuki Kinoshita,Satoshi Nagai,Koro Gotoh,Takuya Nomura,Yukie Tanimura,Hirotaka Shibata,Yuichi Yoshida,Shotaro Miyamoto,Kanako Shibuta,Kengo Kambara,Naoki Matsuda,Takayuki Masaki,Mitsuhiro Okamoto

doi:10.3390/diagnostics11030433

Yoshinori Ozeki, Mizuki Kinoshita + Show 12 more

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https://doi.org/10.3390/diagnostics11030433

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Journal: Diagnostics	Publication Date: Mar 4, 2021
Citations: 18	License type: CC BY 4.0

Affiliation: Oita University, Fujifilm (Japan)

Abstract

In the present study, we developed a new chemiluminescent enzyme immunoassay (CLEIA) using a two-step sandwich method to measure aldosterone concentrations. We investigated serum and plasma aldosterone concentrations in 75 blood samples from 27 patients using a radioimmunoassay (RIA) and the CLEIA (with current and newly improved reagents) as well as liquid chromatography-tandem mass spectrometry (LC-MS/MS). Based on the results of the Passing–Bablok regression analysis, the aldosterone levels measured using CLEIA with the new reagents and those measured by LC-MS/MS were found to be significantly correlated (slope, 0.984; intercept, 0.2). However, aldosterone levels varied depending on the measurement method (i.e., CLEIA with the new reagent, CLEIA with the current reagent, and RIA). Aldosterone levels were lower with the improved CLEIA method than with RIA and CLEIA using the current reagent. Therefore, the cutoff values of the screening test as well as those of the confirmatory test for primary aldosteronism (PA) should be adjusted to follow current clinical practice guidelines for PA. The formula that can be used to obtain the aldosterone level (pg/mL) when using CLEIA with the new reagent is 0.765 × RIA (pg/mL) − 33.7. This formula will enable PA cutoff values to be set for provisional screening and confirmatory tests.

Highlights

Primary aldosteronism (PA) is the most frequent cause of secondary hypertension, and 5–10% of patients with hypertension have PA [1,2,3]
The results showed that the aldosterone concentrations measured with the new chemiluminescent enzyme immunoassay (CLEIA) kit were highly correlated with those measured with LC-MS/MS; the concentrations were lower than those obtained using the current CLEIA kit and RIA
No significant differences were observed in the plasma aldosterone concentration (PAC) or active renin concentration ratio (ARC) between between groups, but the aldosterone to renin ratio (ARR) was significantly higher in PA patients than in non-PA pagroups, but the ARR was significantly higher in PA patients than in non-PA patients

Summary

Introduction

Primary aldosteronism (PA) is the most frequent cause of secondary hypertension, and 5–10% of patients with hypertension have PA [1,2,3]. PA causes hypertension and hypokalemia due to excessive aldosterone secretion by the adrenal glands [4,5]. Patients with PA have an increased risk of cardiovascular events, such as cerebral infarction, myocardial infarction, and chronic kidney disease, compared to those with essential hypertension, and early diagnosis makes PA a treatable disease [6,7,8,9]. The aldosterone to renin ratio (ARR) is used as a screening test for PA [2,10,11]. In Japan, the screening cutoff values for PA diagnosis are a plasma aldosterone concentration (PAC)

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