Comparison of chemiluminescence immunoassay with LC-MS/MS in the determination of plasma aldosterone concentration in patients with declined renal function

Comparison of chemiluminescence immunoassay with LC-MS/MS in the determination of plasma aldosterone concentration in patients with declined renal function | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Comparison of chemiluminescence immunoassay with LC-MS/MS in the determination of plasma aldosterone concentration in patients with declined renal function Qiurong Zeng, Junlong Li, Yi Yang, Yifan He, Ying Song, Jinbo Hu, and 3 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-4336691/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Purpose Compared with chemiluminescence immunoassay (CLIA), quantification of plasma aldosterone concentration (PAC) by liquid chromatography-tandem mass spectrometry (LC-MS/MS) yields lower values. Whether this difference is exacerbated by a declined glomerular filtration rate (eGFR) is unclear. Therefore, this study aims to assess the impact of renal insufficiency on PAC measured by CLIA using LC-MS/MS as the reference method. Methods In subjects with normal or declined estimated glomerular filtration rate (eGFR), PAC were measured by both LC-MS/MS and two different CLIA kits (Mindray and Diasorin). Results 383 patients were included in our study. Among them, there were 71 subjects with eGFR > 90 (group one), 79 with eGFR 60–89 (group two), 108 with eGFR 30–59 (group three), 51 with eGFR 15–29 (group four), and 74 with eGFR < 15 (group five) ml/min per 1.73m 2 , respectively. In all subjects, PAC measured by CLIA [68.2(37.1-122.1) pg/ml for Mindray, 109.0(68.1–170.0) pg/ml for Diasorin] were significantly increased compared with those measured by LC-MS/MS [47.2(22.9–88.7) pg/ml]. The PAC measured by CLIA was positively correlated with that by LC-MS/MS, but the correlation coefficient diminished gradually with eGFR decline. Between LC-MS/MS and Diasorin CLIA kit, the difference of PAC increased with declined eGFR in groups one to five (76.8%, 69.2%, 113.2%, 152.2% and 476.2% for groups one to five, respectively). However, the difference increased only in group five in Mindray CLIA kit (46.4%, 48.1%, 45.7%, 45.0% and 74.9% for group one to five, respectively). Conclusion In patients with declined renal function, PAC measured by CLIA might be overestimated. Caution is needed in the interpretation of PAC in patients with severe renal impairment. When accurate measurements are required, LC-MS/MS should be considered. Plasma Aldosterone Liquid chromatography-tandem mass spectrometry Chemiluminescence assays Renal function Figures Figure 1 Introduction Aldosterone, an important mineralocorticoid secreted by the zona glomerulosa of the adrenal cortex, plays an essential role in regulating water and salt balance as well as blood pressure. Excessive or insufficient levels of aldosterone can result in a range of endocrine disorders and diseases. As we all know, primary aldosteronism (PA), which is one of the most common causes of secondary hypertension, accounting for 5%-10% of all hypertensive patients[ 1 ], is characterized by the autonomous secretion of aldosterone. Accurate measurement of plasma aldosterone concentration (PAC) is essential for the diagnosis of PA[ 2 – 4 ]. Moreover, PAC is also commonly used in the diagnosis of other endocrine hypertension, such as secondary aldosteronism and congenital adrenal hyperplasia. Therefore, the accurate measurement of PAC is crucial in the clinic. The methods of PAC measurement mainly include immunoassay and liquid chromatography-tandem mass spectrometry (LC-MS/MS). Currently, PAC is mostly determined by immunoassays, including radioimmunoassay (RIA) and chemiluminescence immunoassay (CLIA). CLIA has been widely used in clinical laboratories owing to its convenience and low cost. However, since these immunoassays are based on the antigen-antibody reaction, there is a risk of interference from nonspecific reactions and cross-reactivity. Accordingly, CLIA is less accurate in measuring PAC than LC-MS/MS, which has been considered the “gold standard” [ 5 , 6 ]. Renal impairment is common in clinical practice. Two studies have reported that PAC measured by immunoassay without solvent extraction in patients with renal impairment was significantly higher than that of the method with solvent extraction[ 7 , 8 ], suggesting that renal insufficiency may affect the PAC measured by the immunoassay. However, there is no study comparing LC-MS/MS and immunoassay in the detection of PAC in patients with declined glomerular filtration rate. Thus, Our study aims to evaluate the effect of declined renal function on PAC measured by CLIA using LC-MS/MS as the reference method. The results of this study may provide valuable insights into the accurate assessment of PAC. Methods Subjects The study was approved by the Ethics Committee of the First Affiliated Hospital of Chongqing Medical University. The Ethics Committee waived informed consent because it was a retrospective study. Residual plasma samples of inpatients with different levels of glomerular filtration rate in the endocrine laboratory of the First Affiliated Hospital of Chongqing Medical University were collected from March 2022 to July 2022. The patients were categorized into Groups 1–5 according to the estimated glomerular filtration rate (eGFR) which was calculated by the CKD-EPI formula[ 9 ]. Group 1: eGFR > 90 ml/min per 1.73m 2 ; Group 2: eGFR 60–89 ml/min per 1.73m 2 ; Group 3: eGFR 30–59 ml/min per 1.73m 2 ; Group 4: eGFR 15–29 ml; Group 5: eGFR < 15 ml/min per 1.73m 2 . Electronic medical record of the patients was examined to collect the data of age, sex, height, weight, blood pressure, glucose, glutamic-pyruvic transaminase, glutamic oxalacetic transaminase, urea nitrogen, serum creatinine, and hemoglobin at admission. Patients with elevated glutamic-pyruvic transaminase or glutamic oxalacetic transaminase greater than 3 times the upper limit of normal were excluded. PAC Measurements For PAC measurements, residual plasma samples were stored in a refrigerator at -20°C, and rapidly re-melted in a 37°C water bath before PAC assay. Two CLIA kits were used to determine PAC (DiaSorin, Italy; Mindray, China). The PAC assay of Diasorin has a measuring range from 30 pg/ml to 1000 pg/ml. The intra-assay coefficient of variation for PAC assay of Diasorin was from 1.8–4.2% and the inter-assay coefficient of variation was from 5.6–10.5%. The PAC assay of Mindray has a measuring range from 12 pg/ml to 2000 pg/ml. The intra-assay coefficient of variation for PAC assay of Mindray was from 1.1–3.4% and the inter-assay coefficient of variation was from 2.8–6.6%. For LC-MS/MS measurement, 300 µl of sample was added to a stable isotope-labeled internal standard working solution and underwent a protein precipitation procedure using a mixture of zinc sulfate solution and methanol as the protein precipitant. Subsequently, the resulting supernatant underwent C18-based solid-phase extraction for further purification and fractionated elution of aldosterone. The eluent was then analyzed using LC-MS/MS on a reversed-phase analytical column (ACQUITY UPLC BEH C18 column, 2.1mm × 100 mm, 1.7µm, Waters, USA) coupled with a Thermo Ultimate 3000 UPLC and TSQ Endura triple quadrupole mass spectrometer (Thermo Fisher Scientific, USA) equipped with an ESI ion source operating in multiple reaction monitoring mode. The concentrations of the analyte were determined by calculating the integrated chromatograms using appropriate calibration curves established in the plasma matrix, considering the corresponding response factors. Signals with a signal-to-noise ratio exceeding 10 were considered for the calculations. The measurement range spanned from 10 to 10000 pg/ml. The recoveries of PAC determined by LC-MS/MS ranged from 98.3–102.2%, with relative standard deviations below 5.1%. The inter-assay and intra-assay coefficients of variation for PAC were 2.7–5.0% and 1.8–3.2%, respectively. Statistical analysis Med Calc 19.1.3 was used for statistical analysis. Variables with normal distribution were expressed as mean ± standard deviation (SD), and comparison between the two groups was analyzed by independent sample t-test. Variables with skewed distribution were expressed as median (interquartile range) and Mann-Whitney U test was used for comparison between groups. Bland Altman plots were used to evaluate the concordance of CLIA and LC-MS/MS. P<0.05 was considered statistically significant. Results Patients with elevated glutamic-pyruvic transaminase or glutamic oxalacetic transaminase greater than 3 times the upper limit of normal were excluded, and 383 participants were included in our study. Among them, there were 71 subjects with eGFR > 90 (group one), 79 with eGFR 60–89 (group two), 108 with eGFR 30–59 (group three), 51 with eGFR 15–29 (group four), and 74 with eGFR < 15 (group five) ml/min per 1.73m 2 , respectively. The clinical characteristics of the subjects were shown in Table 1 . Significant differences were observed in age, systolic blood pressure, alanine aminotransferase, aspartate aminotransferase, urea nitrogen, serum creatinine, eGFR, fasting plasma glucose, and hemoglobin among five groups. There were no significant differences in terms of sex, body mass index, and diastolic blood pressure among those in group one to five. Table 1 Characteristics of the Patients Characteristics Total (n = 383) Group 1 (n = 71) Group 2 (n = 79) Group 3 (n = 108) Group 4 (n = 51) Group 5 (n = 74) P value Female, n (%) 158(41.3) 35(49.2) 37(46.8) 34(31.4) 21(41.1) 31(41.8) 0.127 Age (y) 64.0(64.2 ± 14.7) 57(57.6 ± 11.7) 58(59.2 ± 11.2) 70(67.8 ± 16.4) 72(70.1 ± 13.3) 68.5(66.6 ± 15.4) < 0.001 BMI (kg/m 2 ) 23.8(24.2 ± 4.3) 23.8(24.1 ± 4.0) 23.8(24.4 ± 3.3) 24.2(24.4 ± 4.8) 23.2(23.9 ± 4.5) 23.6(23.8 ± 4.6) 0.772 SBP (mmHg) 136(139 ± 24) 131(133 ± 19) 135(136 ± 24) 134(136 ± 26) 141(142 ± 23) 148(148 ± 23) < 0.001 DBP (mmHg) 79(80 ± 15) 78(81 ± 13) 82(82 ± 14) 77(78 ± 17) 74(77 ± 15) 78(80 ± 14) 0.101 ALT (U/L) 16(12,25) 20(14,32) 18(12,22) 16(11,25) 18(12,27) 13(9,16) < 0.001 AST (U/L) 19(15,26) 20(15,27) 19(16,24) 20(16,26) 22(16,38) 17(14,22) 0.005 Urea nitrogen (mmol/L) 8.6(5.9,15.1) 5.1(4.4,6.2) 6.0(4.7,6.9) 9.6(7.6,13.1) 14.1(11.6,17.3) 19.2(15.1,26.4) < 0.001 Serum creatinine (µmol/L) 124(75,250) 59(53,69) 80(69,91) 135(112,160) 226(190,296) 597(460,792) < 0.001 eGFR (ml/min per 1.73m 2 ) 60.3(29.8,94.4) 109.5(103.1,118.0) 82.9(74.4,91.9) 43.6(37.6,56.9) 23.4(18.3,27.3) 7.3(5.6,10.4) < 0.001 Fasting plasma glucose (mmol/L) 5.7(5.1,7.5) 5.5(5.0,6.4) 5.6(5.1,7.2) 5.8(4.9,6.7) 5.9(5.3,10.7) 7.3(5.5,12.1) 0.027 Hemoglobin (g/L) 120(101,134) 131(121,146) 131(123,142) 117(102,133) 105(90,120) 94(81,107) < 0.001 Data were presented as mean ± SE or median (IQR) for continuous variables or numbers (percentages) for categorical variables. BMI, body mass index; SBP, systolic blood pressure; DBP, diastolic blood pressure; ALT, alanine aminotransferase; AST, aspartate aminotransferase; eGFR, estimated glomerular filtration rate; Hb, hemoglobin. In all subjects, PAC measured by CLIA [Mindray: 68.2 (37.1-122.1) pg/ml; Diasorin: 109.0 (68.1–170.0) pg/ml] significantly increased compared with those measured by LC-MS/MS[47.2(37.1-122.1)pg/ml]. In group one to five, the difference of PAC between LC-MS/MS and Diasorin CLIA kit was exacerbated with declined eGFR(76.8%, 69.2%, 113.2%, 152.2% and 476.2% for group one to five). However, the difference of PAC between LC-MS/MS and Mindray CLIA kit increased only in group five (46.4%, 48.1%, 45.7%, 45.0% and 74.9% for group one to five) (Table 2 ). Table 2 Plasma Aldosterone Concentration Measured by LC-MC/MS and CLIA Total (n = 383) Group 1 (n = 71) Group 2 (n = 79) Group 3 (n = 108) Group 4 (n = 51) Group 5 (n = 74) P value PAC LC−MC/MS (pg/ml) 47.2(22.9,88.7) 60.5(35.5,104.6) 63.4(35.5,111.2) 38.7(17.2,77.89) 54.1(19.2,89.4) 24.1(13.5,57.2) < 0.001 PAC CLIA Mindray (pg/ml) 68.2(37.1,122.1) 79.6(52.4,139.6) 100.4(54.1,140.6) 56.6(27.3,104.0) 66.6(30.9,99.2) 38.5(17.7,110.5) < 0.001 Changes of PAC CLIA Mindray (%) 48.1(23.8,74.7) 46.4(29.2,69.3) 48.1(25.6,60.0) 45.7(18.6,75.9) 45.0(14.9,78.2) 74.9(22.2,113.3) 0.029 PAC CLIA Diasorin (pg/ml) 109.0(68.1,170.0) 97.8(68.1,155.0) 117.0(78.9,159.0) 94.45(57.4,146.8) 127.0(67.5,248.0) 142.0(82.6,332.0) 0.004 Changes of PAC CLIA Diasorin (%) 110(57.6,276.5) 76.8(41.5,108.5) 69.2(39.6,115.7) 113.2(66.2,227.4) 152.2(48.7,305.9) 476.2(261.6,1054.6) < 0.001 PAC, plasma aldosterone concentration; LC-MC/MS, Liquid chromatography-tandem mass spectrometry; CLIA, chemiluminescent immunoassay. Spearman correlation analysis showed that the PAC measured by CLIA was positively correlated with that by LC-MS/MS, but the correlation coefficient diminished gradually with the decrease of eGFR (Table 3 ). Table 3 Spearman Correlation Analysis for PAC Measured by LC-MS/MS and by CLIA Group 1 (n = 71) Group 2 (n = 79) Group 3 (n = 108) Group 4 (n = 51) Group 5 (n = 74) LC-MC/MS – CLIA Mindray 0.957 0.955 0.936 0.904 0.899 LC-MC/MS – CLIA Diasorin 0.896 0.807 0.785 0.725 0.661 PAC, plasma aldosterone concentration; LC-MC/MS, Liquid chromatography-tandem mass spectrometry; CLIA, chemiluminescence immunoassay. Bland-Altman analysis for PAC measured by LC-MS/MS and by Mindray CLIA showed that there were7.0% (5/71), 2.5% (2/79), 8.6% (9/105), 9.1% (4/44) and 8.7% (6/69) located outside the limits of agreement in groups one to five, respectively (Fig. 1 ). Bland-Altman analysis for PAC measured by LC-MS/MS and by DiaSorin CLIA showed that there were 4.2% (3/71), 5.1% (4/79), 6.5% (7/108), 5.9% (3/51), and 6.8% (5/74) located outside the limits of agreement in group one to five, respectively (Fig. 1 ). Discussion In this study, PAC determined by LC-MS/MS and CLIA were compared in patients with different levels of eGFR. We found that PAC determined by CLIA were overestimated compared with those by LC-MS/MS, and the overestimation of PAC by different CLIA kits varied greatly. The average deviation of PAC measured by Mindray CLIA was 48.1% and that measured by Diasorin CLIA was 110%. The PAC measured by CLIA was positively correlated with that by LC-MS/MS, but the correlation coefficient diminished gradually with the decline of eGFR. The deviation of PAC measured by Diasorin CLIA is as high as 476% in group five which included the patients with very low eGFR (< 30 ml/min per 1.73m 2 ). These findings suggest that PAC measured by CLIA could be affected by declined renal function, which is consistent with previous studies[ 6 – 8 ], and in addition, the extent of the effect varies with different kits. As an important indicator for screening and confirming the diagnosis of PA, PAC is of great significance for its accurate quantification. Currently, the main methods for aldosterone determination are radioimmunoassay, CLIA and LC-MS/MS. Compared with radioimmunoassay, CLIA method has the advantages of automatizability, good reproducibility and rapidity[ 1 , 10 ]. Besides, it has no radioimmunoassay contamination and is thus recommended by the guidelines. At present, immunoassays have been widely used for determining PAC in clinical laboratories in China. Several studies have demonstrated a large difference in the determination of PAC by CLIA compared with the results of LC-MS/MS[ 5 , 10 – 13 ], which has been considered the “gold standard” for determining PAC under its high specificity and sensitivity[ 5 ]. Two small-sample studies have reported that renal insufficiency may affect the PAC measured by the immunoassay. Lam et al[ 7 ]included 24 patients on hemodialysis, 41 patients with varying degrees of renal impairment (eGFR 30–90 ml/min per 1.73m 2 ), and 21 subjects with normal renal function as control. They performed aldosterone measurements by CLIA with solvent extraction (dichloromethane and other reagents) step and without solvent extraction step respectively. The study found that PAC measured by the immunoassay without solvent extraction was significantly higher compared with the immunoassay with solvent extraction, and the magnitude of this bias increased with the worsening of renal function. In comparison to results for individuals with normal renal function, the assay overestimated aldosterone on average by 129% in hemodialysis patients and 42% in moderate renal impairment (eGFR 30–60 ml/min per 1.73m 2 ) and 27% in patients with mild renal impairment (eGFR 60–90 ml/min per 1.73m 2 ). Hartman et al [ 7 ] included 37 subjects with normal renal function, 19 patients with regular hemodialysis, and 11 patients with low-clearance-chronic renal failure not receiving dialysis. PAC was determined by CLIA with and without solvent extraction (dichloromethane and other reagents) respectively. In patients with normal renal function, a significantly strong correlation (r 2 = 0.90) was observed between PAC measurements obtained with and without the extraction methods. By contrast, there was poor agreement between the two methods for patients with renal failure (patients not receiving dialysis: r 2 = 0.83, patients with regular hemodialysis: r 2 = 0.79). The above studies utilized chemical reagents to eliminate some interfering metabolites in blood samples before determining PAC by CLIA. However, as interfering metabolites may not be completely cleared from plasma in patients with renal insufficiency, this method is hard to measure PAC accurately. Our study found that the PAC measured by LC-MS/MS, which is considered the reference standard, provides a more accurate reflection of the deviation between the results of CLIA and the true aldosterone level in plasma. Similar to previous studies, we found that renal insufficiency affects the PAC determined by CLIA. Our study also showed that the PAC determined by LC-MS/MS was lower than that by CLIA. Since the CLIA is based on the antigen-antibody reaction, interference from non-specific reactions and cross-reactivity are inevitable. The aldosterone concentration detected by CLIA is the sum of the aldosterone and its metabolites, such as aldosterone 3C-glucuronide, due to the lack of antibody specificity[ 14 ]. Aldosterone 3C-glucuronide is present in normal human serum and excreted in the urine. However, an elevated concentration of aldosterone 3C-glucuronate was accumulated in the plasma of these patients with renal insufficiency[ 7 ]. While LC-MS/MS is based on the principle of liquid-phase separation and combined with the characteristic property of kernel ratio, which gives it high specificity and little cross-reactivity with aldosterone metabolites, therefore, PAC determined by LC-MS/MS is lower than that by CLIA. One of the main strengths of our study is the larger sample size of patients with varying levels of eGFR when compared with previous studies. Another strength of our study is the use of LC-MS/MS as the reference standard and the simultaneous evaluation of the results of two CLIA methods. Limitations of our study need to be mentioned. Firstly, the study is a single-center, retrospective design. Besides, our study did not assess the accuracy of PAC measured by radioimmunoassay. In conclusion, in patients with declined renal function, PAC measured by CLIA might be overestimated, and the more severe the renal insufficiency, the greater the overestimation is likely to be. Caution is needed in the interpretation of PAC in patients with severe renal impairment. When accurate measurements are required, LC-MS/MS should be considered. Declarations Funding Source: This work is supported by the National Natural Science Foundation of China (82170825 and U21A20355); Joint Medical Research Project of Chongqing Science and Technology Commission & Chongqing Health and Family Planning Commission (Major Project, 2022ZDXM003). National key research & development plan of China, major project of prevention and treatment for common diseases (2021YFC2501600, sub-project: 2021YFC2501603). Disclosures: Authors have disclosed no conflicts of interest. Contributors: Conception and design: S.Y. and Q.L. Acquisition, analysis, or interpretation of data: Q.Z. and J.H. Drafting of the article: Q.Z. Critical revision of the article for important intellectual content: J.H., Y.S., J.L.,Y.Y., and Y.W. Obtaining of funding: Q.L., Y.Y., and J.H. Ethics approval: This is a retrospective study. The Ethics Committee of the First Affiliated Hospital of Chongqing Medical University has confirmed that no ethical approval is required. Data sharing: Shumin Yang had full access to all the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis. Acknowledgments: We thank other members of the Chongqing Primary Aldosteronism Study (CONPASS) Group: Mei Mei, MD, PhD; Suxin Luo, MD, PhD; Kangla Liao, MD; Yao Zhang, MD, PhD; Yunfeng He, MD, PhD; Yihong He, MD; Ming Xiao, PhD; and Bin Peng, PhD for suggestions of study design and revision. 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Journal of Chromatography B. 970, 102-107 (2014). https://doi.org/10.1016/j.jchromb.2014.08.042. Eisenhofer G, Kurlbaum M, Peitzsch M, et al.: The Saline Infusion Test for Primary Aldosteronism: Implications of Immunoassay Inaccuracy. The Journal of Clinical Endocrinology & Metabolism. 107, e2027-e2036 (2022). https://doi.org/10.1210/clinem/dgab924. Yin Y, Ma C, Yu S, et al.: Comparison of three different chemiluminescence assays and a rapid liquid chromatography tandem mass spectrometry method for measuring serum aldosterone. Clinical Chemistry and Laboratory Medicine (CCLM). 58, 95-102 (2019). https://doi.org/10.1515/cclm-2019-0706. Blocki F, Zierold C, Olson G, et al.: In defense of aldosterone measurement by immunoassay: a broader perspective. Clinical Chemistry and Laboratory Medicine (CCLM). 55, (2017). https://doi.org/10.1515/cclm-2016-0707. Additional Declarations No competing interests reported. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-4336691","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":298682118,"identity":"fdfa1247-15e8-45cf-af09-64fecd49318b","order_by":0,"name":"Qiurong Zeng","email":"","orcid":"","institution":"The First Affiliated Hospital of Chongqing Medical University","correspondingAuthor":false,"prefix":"","firstName":"Qiurong","middleName":"","lastName":"Zeng","suffix":""},{"id":298682119,"identity":"a34f7061-8ffc-4010-8144-ab76a68f8db0","order_by":1,"name":"Junlong Li","email":"","orcid":"","institution":"The First Affiliated Hospital of Chongqing Medical University","correspondingAuthor":false,"prefix":"","firstName":"Junlong","middleName":"","lastName":"Li","suffix":""},{"id":298682120,"identity":"ad0b9166-49ae-420b-aa5b-4b024dbbf02d","order_by":2,"name":"Yi Yang","email":"","orcid":"","institution":"The First Affiliated Hospital of Chongqing Medical University","correspondingAuthor":false,"prefix":"","firstName":"Yi","middleName":"","lastName":"Yang","suffix":""},{"id":298682121,"identity":"03ac5c66-cd53-41c9-bfcc-26ae43eb0e06","order_by":3,"name":"Yifan He","email":"","orcid":"","institution":"The First Affiliated Hospital of Chongqing Medical University","correspondingAuthor":false,"prefix":"","firstName":"Yifan","middleName":"","lastName":"He","suffix":""},{"id":298682122,"identity":"3600730b-f43c-4fdf-bbdc-ff398a136165","order_by":4,"name":"Ying Song","email":"","orcid":"","institution":"The First Affiliated Hospital of Chongqing Medical University","correspondingAuthor":false,"prefix":"","firstName":"Ying","middleName":"","lastName":"Song","suffix":""},{"id":298682124,"identity":"ed9f2870-165a-4800-9888-b9cb045b1200","order_by":5,"name":"Jinbo Hu","email":"","orcid":"","institution":"The First Affiliated Hospital of Chongqing Medical University","correspondingAuthor":false,"prefix":"","firstName":"Jinbo","middleName":"","lastName":"Hu","suffix":""},{"id":298682126,"identity":"56d3091c-c093-4fc9-ac0d-83c2817fd436","order_by":6,"name":"Yue Wang","email":"","orcid":"","institution":"The First Affiliated Hospital of Chongqing Medical University","correspondingAuthor":false,"prefix":"","firstName":"Yue","middleName":"","lastName":"Wang","suffix":""},{"id":298682129,"identity":"30d399a5-6e43-4875-a6db-835ee80c15fa","order_by":7,"name":"Qifu Li","email":"","orcid":"","institution":"The First Affiliated Hospital of Chongqing Medical University","correspondingAuthor":false,"prefix":"","firstName":"Qifu","middleName":"","lastName":"Li","suffix":""},{"id":298682132,"identity":"b8a0c5b4-75e6-4e27-87a8-e76e23991007","order_by":8,"name":"Shumin Yang","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAAwklEQVRIiWNgGAWjYBACxobjBw58qGCTY2xvIFILc+OZxIczzvAZM/ccIFILe/MBY2PONrnE9hkJRGrhbTuQJs1wxiyxd+bjjTcYamyiCWqR7Dl4TLqgIs145uy0YguGY2m5DYS0GM4A2jLjzDHZjbNzzCQYGw4T1mJ//4GZNG/bf8b9N88QqYWxAeh93jY2xcYZPERrAQcymzFjD9AvCcT4BSkqD2+88aHGhrAWZGAgkUCKcogWUnWMglEwCkbByAAAOF1JZDe6z9EAAAAASUVORK5CYII=","orcid":"","institution":"The First Affiliated Hospital of Chongqing Medical University","correspondingAuthor":true,"prefix":"","firstName":"Shumin","middleName":"","lastName":"Yang","suffix":""}],"badges":[],"createdAt":"2024-04-28 07:28:47","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-4336691/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-4336691/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":56037297,"identity":"94309ed2-546e-44cc-9e78-015d1bd1c41a","added_by":"auto","created_at":"2024-05-07 18:50:28","extension":"jpg","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":1301881,"visible":true,"origin":"","legend":"\u003cp\u003eBland–Altman plots for PAC measured by LC-MS/MS and by CLIA in groups one to five\u003c/p\u003e\n\u003cp\u003eBland–Altman plots for PAC measured by LC-MS/MS and by CLIA Mindray in five groups (a-e); Bland–Altman plots for PAC measured by LC-MS/MS and by CLIA Diasorin in five groups (f-j); PAC, plasma aldosterone concentration; LC-MS/MS, Liquid chromatography-tandem mass spectrometry; CLIA, chemiluminescence immunoassay.\u003c/p\u003e","description":"","filename":"1.jpg","url":"https://assets-eu.researchsquare.com/files/rs-4336691/v1/1d838b774bbb15a9880cb41c.jpg"},{"id":56038891,"identity":"2ed05911-f1ab-417a-b02f-ac15d418da71","added_by":"auto","created_at":"2024-05-07 19:06:30","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":499658,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-4336691/v1/c4881c5f-d0da-46af-98d5-81e1ab539184.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Comparison of chemiluminescence immunoassay with LC-MS/MS in the determination of plasma aldosterone concentration in patients with declined renal function","fulltext":[{"header":"Introduction","content":"\u003cp\u003eAldosterone, an important mineralocorticoid secreted by the zona glomerulosa of the adrenal cortex, plays an essential role in regulating water and salt balance as well as blood pressure. Excessive or insufficient levels of aldosterone can result in a range of endocrine disorders and diseases. As we all know, primary aldosteronism (PA), which is one of the most common causes of secondary hypertension, accounting for 5%-10% of all hypertensive patients[\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e], is characterized by the autonomous secretion of aldosterone. Accurate measurement of plasma aldosterone concentration (PAC) is essential for the diagnosis of PA[\u003cspan additionalcitationids=\"CR3\" citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e]. Moreover, PAC is also commonly used in the diagnosis of other endocrine hypertension, such as secondary aldosteronism and congenital adrenal hyperplasia. Therefore, the accurate measurement of PAC is crucial in the clinic.\u003c/p\u003e \u003cp\u003eThe methods of PAC measurement mainly include immunoassay and liquid chromatography-tandem mass spectrometry (LC-MS/MS). Currently, PAC is mostly determined by immunoassays, including radioimmunoassay (RIA) and chemiluminescence immunoassay (CLIA). CLIA has been widely used in clinical laboratories owing to its convenience and low cost. However, since these immunoassays are based on the antigen-antibody reaction, there is a risk of interference from nonspecific reactions and cross-reactivity. Accordingly, CLIA is less accurate in measuring PAC than LC-MS/MS, which has been considered the \u0026ldquo;gold standard\u0026rdquo; [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e, \u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eRenal impairment is common in clinical practice. Two studies have reported that PAC measured by immunoassay without solvent extraction in patients with renal impairment was significantly higher than that of the method with solvent extraction[\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e, \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e], suggesting that renal insufficiency may affect the PAC measured by the immunoassay. However, there is no study comparing LC-MS/MS and immunoassay in the detection of PAC in patients with declined glomerular filtration rate. Thus, Our study aims to evaluate the effect of declined renal function on PAC measured by CLIA using LC-MS/MS as the reference method. The results of this study may provide valuable insights into the accurate assessment of PAC.\u003c/p\u003e"},{"header":"Methods","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003eSubjects\u003c/h2\u003e \u003cp\u003e The study was approved by the Ethics Committee of the First Affiliated Hospital of Chongqing Medical University. The Ethics Committee waived informed consent because it was a retrospective study. Residual plasma samples of inpatients with different levels of glomerular filtration rate in the endocrine laboratory of the First Affiliated Hospital of Chongqing Medical University were collected from March 2022 to July 2022.\u003c/p\u003e \u003cp\u003eThe patients were categorized into Groups 1\u0026ndash;5 according to the estimated glomerular filtration rate (eGFR) which was calculated by the CKD-EPI formula[\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e]. Group 1: eGFR\u0026thinsp;\u0026gt;\u0026thinsp;90 ml/min per 1.73m\u003csup\u003e2\u003c/sup\u003e; Group 2: eGFR 60\u0026ndash;89 ml/min per 1.73m\u003csup\u003e2\u003c/sup\u003e; Group 3: eGFR 30\u0026ndash;59 ml/min per 1.73m\u003csup\u003e2\u003c/sup\u003e; Group 4: eGFR 15\u0026ndash;29 ml; Group 5: eGFR\u0026thinsp;\u0026lt;\u0026thinsp;15 ml/min per 1.73m\u003csup\u003e2\u003c/sup\u003e.\u003c/p\u003e \u003cp\u003eElectronic medical record of the patients was examined to collect the data of age, sex, height, weight, blood pressure, glucose, glutamic-pyruvic transaminase, glutamic oxalacetic transaminase, urea nitrogen, serum creatinine, and hemoglobin at admission. Patients with elevated glutamic-pyruvic transaminase or glutamic oxalacetic transaminase greater than 3 times the upper limit of normal were excluded.\u003c/p\u003e \u003cdiv id=\"Sec4\" class=\"Section3\"\u003e \u003ch2\u003ePAC Measurements\u003c/h2\u003e \u003cp\u003eFor PAC measurements, residual plasma samples were stored in a refrigerator at -20\u0026deg;C, and rapidly re-melted in a 37\u0026deg;C water bath before PAC assay.\u003c/p\u003e \u003cp\u003eTwo CLIA kits were used to determine PAC (DiaSorin, Italy; Mindray, China). The PAC assay of Diasorin has a measuring range from 30 pg/ml to 1000 pg/ml. The intra-assay coefficient of variation for PAC assay of Diasorin was from 1.8\u0026ndash;4.2% and the inter-assay coefficient of variation was from 5.6\u0026ndash;10.5%. The PAC assay of Mindray has a measuring range from 12 pg/ml to 2000 pg/ml. The intra-assay coefficient of variation for PAC assay of Mindray was from 1.1\u0026ndash;3.4% and the inter-assay coefficient of variation was from 2.8\u0026ndash;6.6%.\u003c/p\u003e \u003cp\u003eFor LC-MS/MS measurement, 300 \u0026micro;l of sample was added to a stable isotope-labeled internal standard working solution and underwent a protein precipitation procedure using a mixture of zinc sulfate solution and methanol as the protein precipitant. Subsequently, the resulting supernatant underwent C18-based solid-phase extraction for further purification and fractionated elution of aldosterone. The eluent was then analyzed using LC-MS/MS on a reversed-phase analytical column (ACQUITY UPLC BEH C18 column, 2.1mm \u0026times; 100 mm, 1.7\u0026micro;m, Waters, USA) coupled with a Thermo Ultimate 3000 UPLC and TSQ Endura triple quadrupole mass spectrometer (Thermo Fisher Scientific, USA) equipped with an ESI ion source operating in multiple reaction monitoring mode. The concentrations of the analyte were determined by calculating the integrated chromatograms using appropriate calibration curves established in the plasma matrix, considering the corresponding response factors. Signals with a signal-to-noise ratio exceeding 10 were considered for the calculations. The measurement range spanned from 10 to 10000 pg/ml. The recoveries of PAC determined by LC-MS/MS ranged from 98.3\u0026ndash;102.2%, with relative standard deviations below 5.1%. The inter-assay and intra-assay coefficients of variation for PAC were 2.7\u0026ndash;5.0% and 1.8\u0026ndash;3.2%, respectively.\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv id=\"Sec5\" class=\"Section2\"\u003e \u003ch2\u003eStatistical analysis\u003c/h2\u003e \u003cp\u003eMed Calc 19.1.3 was used for statistical analysis. Variables with normal distribution were expressed as mean\u0026thinsp;\u0026plusmn;\u0026thinsp;standard deviation (SD), and comparison between the two groups was analyzed by independent sample t-test. Variables with skewed distribution were expressed as median (interquartile range) and Mann-Whitney U test was used for comparison between groups. Bland Altman plots were used to evaluate the concordance of CLIA and LC-MS/MS. P\u0026lt;0.05 was considered statistically significant.\u003c/p\u003e \u003c/div\u003e"},{"header":"Results","content":"\u003cp\u003ePatients with elevated glutamic-pyruvic transaminase or glutamic oxalacetic transaminase greater than 3 times the upper limit of normal were excluded, and 383 participants were included in our study. Among them, there were 71 subjects with eGFR\u0026thinsp;\u0026gt;\u0026thinsp;90 (group one), 79 with eGFR 60\u0026ndash;89 (group two), 108 with eGFR 30\u0026ndash;59 (group three), 51 with eGFR 15\u0026ndash;29 (group four), and 74 with eGFR\u0026thinsp;\u0026lt;\u0026thinsp;15 (group five) ml/min per 1.73m\u003csup\u003e2\u003c/sup\u003e, respectively. The clinical characteristics of the subjects were shown in Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e. Significant differences were observed in age, systolic blood pressure, alanine aminotransferase, aspartate aminotransferase, urea nitrogen, serum creatinine, eGFR, fasting plasma glucose, and hemoglobin among five groups. There were no significant differences in terms of sex, body mass index, and diastolic blood pressure among those in group one to five.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eCharacteristics of the Patients\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"8\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c8\" colnum=\"8\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCharacteristics\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eTotal (n\u0026thinsp;=\u0026thinsp;383)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eGroup 1 (n\u0026thinsp;=\u0026thinsp;71)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eGroup 2 (n\u0026thinsp;=\u0026thinsp;79)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eGroup 3 (n\u0026thinsp;=\u0026thinsp;108)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003eGroup 4 (n\u0026thinsp;=\u0026thinsp;51)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c7\"\u003e \u003cp\u003eGroup 5 (n\u0026thinsp;=\u0026thinsp;74)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c8\"\u003e \u003cp\u003eP value\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eFemale, n (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e158(41.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e35(49.2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e37(46.8)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e34(31.4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e21(41.1)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e31(41.8)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e \u003cp\u003e0.127\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAge (y)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e64.0(64.2\u0026thinsp;\u0026plusmn;\u0026thinsp;14.7)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e57(57.6\u0026thinsp;\u0026plusmn;\u0026thinsp;11.7)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e58(59.2\u0026thinsp;\u0026plusmn;\u0026thinsp;11.2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e70(67.8\u0026thinsp;\u0026plusmn;\u0026thinsp;16.4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e72(70.1\u0026thinsp;\u0026plusmn;\u0026thinsp;13.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e68.5(66.6\u0026thinsp;\u0026plusmn;\u0026thinsp;15.4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eBMI (kg/m\u003csup\u003e2\u003c/sup\u003e)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e23.8(24.2\u0026thinsp;\u0026plusmn;\u0026thinsp;4.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e23.8(24.1\u0026thinsp;\u0026plusmn;\u0026thinsp;4.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e23.8(24.4\u0026thinsp;\u0026plusmn;\u0026thinsp;3.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e24.2(24.4\u0026thinsp;\u0026plusmn;\u0026thinsp;4.8)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e23.2(23.9\u0026thinsp;\u0026plusmn;\u0026thinsp;4.5)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e23.6(23.8\u0026thinsp;\u0026plusmn;\u0026thinsp;4.6)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e \u003cp\u003e0.772\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSBP (mmHg)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e136(139\u0026thinsp;\u0026plusmn;\u0026thinsp;24)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e131(133\u0026thinsp;\u0026plusmn;\u0026thinsp;19)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e135(136\u0026thinsp;\u0026plusmn;\u0026thinsp;24)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e134(136\u0026thinsp;\u0026plusmn;\u0026thinsp;26)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e141(142\u0026thinsp;\u0026plusmn;\u0026thinsp;23)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e148(148\u0026thinsp;\u0026plusmn;\u0026thinsp;23)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eDBP (mmHg)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e79(80\u0026thinsp;\u0026plusmn;\u0026thinsp;15)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e78(81\u0026thinsp;\u0026plusmn;\u0026thinsp;13)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e82(82\u0026thinsp;\u0026plusmn;\u0026thinsp;14)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e77(78\u0026thinsp;\u0026plusmn;\u0026thinsp;17)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e74(77\u0026thinsp;\u0026plusmn;\u0026thinsp;15)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e78(80\u0026thinsp;\u0026plusmn;\u0026thinsp;14)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e \u003cp\u003e0.101\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eALT (U/L)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e16(12,25)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e20(14,32)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e18(12,22)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e16(11,25)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e18(12,27)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e13(9,16)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAST (U/L)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e19(15,26)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e20(15,27)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e19(16,24)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e20(16,26)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e22(16,38)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e17(14,22)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e \u003cp\u003e0.005\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eUrea nitrogen (mmol/L)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e8.6(5.9,15.1)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e5.1(4.4,6.2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e6.0(4.7,6.9)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e9.6(7.6,13.1)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e14.1(11.6,17.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e19.2(15.1,26.4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSerum creatinine (\u0026micro;mol/L)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e124(75,250)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e59(53,69)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e80(69,91)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e135(112,160)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e226(190,296)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e597(460,792)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eeGFR (ml/min per 1.73m\u003csup\u003e2\u003c/sup\u003e)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e60.3(29.8,94.4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e109.5(103.1,118.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e82.9(74.4,91.9)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e43.6(37.6,56.9)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e23.4(18.3,27.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e7.3(5.6,10.4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eFasting plasma glucose (mmol/L)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e5.7(5.1,7.5)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e5.5(5.0,6.4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e5.6(5.1,7.2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e5.8(4.9,6.7)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e5.9(5.3,10.7)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e7.3(5.5,12.1)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e \u003cp\u003e0.027\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHemoglobin (g/L)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e120(101,134)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e131(121,146)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e131(123,142)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e117(102,133)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e105(90,120)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e94(81,107)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"8\"\u003eData were presented as mean\u0026thinsp;\u0026plusmn;\u0026thinsp;SE or median (IQR) for continuous variables or numbers (percentages) for categorical variables. BMI, body mass index; SBP, systolic blood pressure; DBP, diastolic blood pressure; ALT, alanine aminotransferase; AST, aspartate aminotransferase; eGFR, estimated glomerular filtration rate; Hb, hemoglobin.\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eIn all subjects, PAC measured by CLIA [Mindray: 68.2 (37.1-122.1) pg/ml; Diasorin: 109.0 (68.1\u0026ndash;170.0) pg/ml] significantly increased compared with those measured by LC-MS/MS[47.2(37.1-122.1)pg/ml]. In group one to five, the difference of PAC between LC-MS/MS and Diasorin CLIA kit was exacerbated with declined eGFR(76.8%, 69.2%, 113.2%, 152.2% and 476.2% for group one to five). However, the difference of PAC between LC-MS/MS and Mindray CLIA kit increased only in group five (46.4%, 48.1%, 45.7%, 45.0% and 74.9% for group one to five) (Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab2\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003ePlasma Aldosterone Concentration Measured by LC-MC/MS and CLIA\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"8\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c8\" colnum=\"8\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eTotal (n\u0026thinsp;=\u0026thinsp;383)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eGroup 1 (n\u0026thinsp;=\u0026thinsp;71)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eGroup 2 (n\u0026thinsp;=\u0026thinsp;79)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eGroup 3 (n\u0026thinsp;=\u0026thinsp;108)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003eGroup 4 (n\u0026thinsp;=\u0026thinsp;51)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c7\"\u003e \u003cp\u003eGroup 5 (n\u0026thinsp;=\u0026thinsp;74)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c8\"\u003e \u003cp\u003eP value\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePAC\u003csub\u003eLC\u0026minus;MC/MS\u003c/sub\u003e (pg/ml)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e47.2(22.9,88.7)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e60.5(35.5,104.6)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e63.4(35.5,111.2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e38.7(17.2,77.89)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e54.1(19.2,89.4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e24.1(13.5,57.2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePAC \u003csub\u003eCLIA Mindray\u003c/sub\u003e (pg/ml)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e68.2(37.1,122.1)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e79.6(52.4,139.6)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e100.4(54.1,140.6)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e56.6(27.3,104.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e66.6(30.9,99.2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e38.5(17.7,110.5)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eChanges of PAC \u003csub\u003eCLIA Mindray\u003c/sub\u003e (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e48.1(23.8,74.7)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e46.4(29.2,69.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e48.1(25.6,60.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e45.7(18.6,75.9)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e45.0(14.9,78.2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e74.9(22.2,113.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e \u003cp\u003e0.029\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePAC \u003csub\u003eCLIA Diasorin\u003c/sub\u003e (pg/ml)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e109.0(68.1,170.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e97.8(68.1,155.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e117.0(78.9,159.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e94.45(57.4,146.8)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e127.0(67.5,248.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e142.0(82.6,332.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e \u003cp\u003e0.004\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eChanges of PAC \u003csub\u003eCLIA Diasorin\u003c/sub\u003e (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e110(57.6,276.5)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e76.8(41.5,108.5)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e69.2(39.6,115.7)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e113.2(66.2,227.4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e152.2(48.7,305.9)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e476.2(261.6,1054.6)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"8\"\u003ePAC, plasma aldosterone concentration; LC-MC/MS, Liquid chromatography-tandem mass spectrometry; CLIA, chemiluminescent immunoassay.\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eSpearman correlation analysis showed that the PAC measured by CLIA was positively correlated with that by LC-MS/MS, but the correlation coefficient diminished gradually with the decrease of eGFR (Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab3\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 3\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eSpearman Correlation Analysis for PAC Measured by LC-MS/MS and by CLIA\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"6\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eGroup 1 (n\u0026thinsp;=\u0026thinsp;71)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eGroup 2 (n\u0026thinsp;=\u0026thinsp;79)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eGroup 3 (n\u0026thinsp;=\u0026thinsp;108)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eGroup 4 (n\u0026thinsp;=\u0026thinsp;51)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003eGroup 5 (n\u0026thinsp;=\u0026thinsp;74)\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eLC-MC/MS \u0026ndash; CLIA Mindray\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e0.957\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0.955\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.936\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.904\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0.899\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eLC-MC/MS \u0026ndash; CLIA Diasorin\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e0.896\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0.807\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.785\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.725\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0.661\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"6\"\u003ePAC, plasma aldosterone concentration; LC-MC/MS, Liquid chromatography-tandem mass spectrometry; CLIA, chemiluminescence immunoassay.\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eBland-Altman analysis for PAC measured by LC-MS/MS and by Mindray CLIA showed that there were7.0% (5/71), 2.5% (2/79), 8.6% (9/105), 9.1% (4/44) and 8.7% (6/69) located outside the limits of agreement in groups one to five, respectively (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). Bland-Altman analysis for PAC measured by LC-MS/MS and by DiaSorin CLIA showed that there were 4.2% (3/71), 5.1% (4/79), 6.5% (7/108), 5.9% (3/51), and 6.8% (5/74) located outside the limits of agreement in group one to five, respectively (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e).\u003c/p\u003e "},{"header":"Discussion","content":"\u003cp\u003eIn this study, PAC determined by LC-MS/MS and CLIA were compared in patients with different levels of eGFR. We found that PAC determined by CLIA were overestimated compared with those by LC-MS/MS, and the overestimation of PAC by different CLIA kits varied greatly. The average deviation of PAC measured by Mindray CLIA was 48.1% and that measured by Diasorin CLIA was 110%. The PAC measured by CLIA was positively correlated with that by LC-MS/MS, but the correlation coefficient diminished gradually with the decline of eGFR. The deviation of PAC measured by Diasorin CLIA is as high as 476% in group five which included the patients with very low eGFR (\u0026lt;\u0026thinsp;30 ml/min per 1.73m\u003csup\u003e2\u003c/sup\u003e). These findings suggest that PAC measured by CLIA could be affected by declined renal function, which is consistent with previous studies[\u003cspan additionalcitationids=\"CR7\" citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e], and in addition, the extent of the effect varies with different kits.\u003c/p\u003e \u003cp\u003eAs an important indicator for screening and confirming the diagnosis of PA, PAC is of great significance for its accurate quantification. Currently, the main methods for aldosterone determination are radioimmunoassay, CLIA and LC-MS/MS. Compared with radioimmunoassay, CLIA method has the advantages of automatizability, good reproducibility and rapidity[\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e, \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e]. Besides, it has no radioimmunoassay contamination and is thus recommended by the guidelines. At present, immunoassays have been widely used for determining PAC in clinical laboratories in China. Several studies have demonstrated a large difference in the determination of PAC by CLIA compared with the results of LC-MS/MS[\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e, \u003cspan additionalcitationids=\"CR11 CR12\" citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e], which has been considered the \u0026ldquo;gold standard\u0026rdquo; for determining PAC under its high specificity and sensitivity[\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eTwo small-sample studies have reported that renal insufficiency may affect the PAC measured by the immunoassay. Lam et al[\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]included 24 patients on hemodialysis, 41 patients with varying degrees of renal impairment (eGFR 30\u0026ndash;90 ml/min per 1.73m\u003csup\u003e2\u003c/sup\u003e), and 21 subjects with normal renal function as control. They performed aldosterone measurements by CLIA with solvent extraction (dichloromethane and other reagents) step and without solvent extraction step respectively. The study found that PAC measured by the immunoassay without solvent extraction was significantly higher compared with the immunoassay with solvent extraction, and the magnitude of this bias increased with the worsening of renal function. In comparison to results for individuals with normal renal function, the assay overestimated aldosterone on average by 129% in hemodialysis patients and 42% in moderate renal impairment (eGFR 30\u0026ndash;60 ml/min per 1.73m\u003csup\u003e2\u003c/sup\u003e) and 27% in patients with mild renal impairment (eGFR 60\u0026ndash;90 ml/min per 1.73m\u003csup\u003e2\u003c/sup\u003e). Hartman et al [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e] included 37 subjects with normal renal function, 19 patients with regular hemodialysis, and 11 patients with low-clearance-chronic renal failure not receiving dialysis. PAC was determined by CLIA with and without solvent extraction (dichloromethane and other reagents) respectively. In patients with normal renal function, a significantly strong correlation (r\u003csup\u003e2\u003c/sup\u003e\u0026thinsp;=\u0026thinsp;0.90) was observed between PAC measurements obtained with and without the extraction methods. By contrast, there was poor agreement between the two methods for patients with renal failure (patients not receiving dialysis: r\u003csup\u003e2\u003c/sup\u003e\u0026thinsp;=\u0026thinsp;0.83, patients with regular hemodialysis: r\u003csup\u003e2\u003c/sup\u003e\u0026thinsp;=\u0026thinsp;0.79).\u003c/p\u003e \u003cp\u003eThe above studies utilized chemical reagents to eliminate some interfering metabolites in blood samples before determining PAC by CLIA. However, as interfering metabolites may not be completely cleared from plasma in patients with renal insufficiency, this method is hard to measure PAC accurately. Our study found that the PAC measured by LC-MS/MS, which is considered the reference standard, provides a more accurate reflection of the deviation between the results of CLIA and the true aldosterone level in plasma. Similar to previous studies, we found that renal insufficiency affects the PAC determined by CLIA.\u003c/p\u003e \u003cp\u003eOur study also showed that the PAC determined by LC-MS/MS was lower than that by CLIA. Since the CLIA is based on the antigen-antibody reaction, interference from non-specific reactions and cross-reactivity are inevitable. The aldosterone concentration detected by CLIA is the sum of the aldosterone and its metabolites, such as aldosterone 3C-glucuronide, due to the lack of antibody specificity[\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e]. Aldosterone 3C-glucuronide is present in normal human serum and excreted in the urine. However, an elevated concentration of aldosterone 3C-glucuronate was accumulated in the plasma of these patients with renal insufficiency[\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]. While LC-MS/MS is based on the principle of liquid-phase separation and combined with the characteristic property of kernel ratio, which gives it high specificity and little cross-reactivity with aldosterone metabolites, therefore, PAC determined by LC-MS/MS is lower than that by CLIA.\u003c/p\u003e \u003cp\u003eOne of the main strengths of our study is the larger sample size of patients with varying levels of eGFR when compared with previous studies. Another strength of our study is the use of LC-MS/MS as the reference standard and the simultaneous evaluation of the results of two CLIA methods. Limitations of our study need to be mentioned. Firstly, the study is a single-center, retrospective design. Besides, our study did not assess the accuracy of PAC measured by radioimmunoassay.\u003c/p\u003e \u003cp\u003eIn conclusion, in patients with declined renal function, PAC measured by CLIA might be overestimated, and the more severe the renal insufficiency, the greater the overestimation is likely to be. Caution is needed in the interpretation of PAC in patients with severe renal impairment. When accurate measurements are required, LC-MS/MS should be considered.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eFunding Source:\u003c/strong\u003e This work is supported by the National Natural Science Foundation of China (82170825 and U21A20355); Joint Medical Research Project of Chongqing Science and Technology Commission \u0026amp; Chongqing Health and Family Planning Commission (Major Project, 2022ZDXM003). National key research \u0026amp; development plan of China, major project of prevention and treatment for common diseases (2021YFC2501600, sub-project: 2021YFC2501603).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eDisclosures:\u0026nbsp;\u003c/strong\u003eAuthors have disclosed no conflicts of interest.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eContributors:\u0026nbsp;\u003c/strong\u003eConception and design: S.Y. and Q.L.\u003c/p\u003e\n\u003cp\u003eAcquisition, analysis, or interpretation of data: Q.Z. and J.H.\u003c/p\u003e\n\u003cp\u003eDrafting of the article: Q.Z.\u003c/p\u003e\n\u003cp\u003eCritical revision of the article for important intellectual content: J.H., Y.S., J.L.,Y.Y., and Y.W.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eObtaining of funding: Q.L., Y.Y., and J.H.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eEthics approval:\u0026nbsp;\u003c/strong\u003eThis is a retrospective study. The Ethics Committee of the First Affiliated Hospital of Chongqing Medical University has confirmed that no ethical approval is required.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eData sharing: \u003c/strong\u003eShumin Yang had full access to all the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAcknowledgments:\u0026nbsp;\u003c/strong\u003eWe thank other members of the Chongqing Primary Aldosteronism Study (CONPASS) Group: Mei Mei, MD, PhD; Suxin Luo, MD, PhD; Kangla Liao, MD; Yao Zhang, MD, PhD; Yunfeng He, MD, PhD; Yihong He, MD; Ming Xiao, PhD; and Bin Peng, PhD for suggestions of study design and revision.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eFunder JW, Carey RM, Mantero F, et al.: The Management of Primary Aldosteronism: Case Detection, Diagnosis, and Treatment: An Endocrine Society Clinical Practice Guideline. The Journal of Clinical Endocrinology \u0026amp; Metabolism. 101, 1889-1916\u003cem\u003e \u003c/em\u003e(2016). https://doi.org/10.1210/jc.2015-4061. \u003c/li\u003e\n\u003cli\u003eMitsuhide Naruse, Shibata TKH. Japan Endocrine Society clinical practice guideline for the diagnosis and management of primary aldosteronism 2021. Endocrine Journal. 69, 327-359\u003cem\u003e \u003c/em\u003e(2022). https://doi.org/10.1507/endocrj.EJ21-0508. \u003c/li\u003e\n\u003cli\u003eMulatero P, Monticone S, Deinum J, et al.: Genetics, prevalence, screening and confirmation of primary aldosteronism: a position statement and consensus of the Working Group on Endocrine Hypertension of The European Society of Hypertension \u0026lowast;. Journal of Hypertension. 38, 1919-1928\u003cem\u003e \u003c/em\u003e(2020). https://doi.org/10.1097/hjh.0000000000002510. \u003c/li\u003e\n\u003cli\u003eMulatero P, Sechi LA, Williams TA, et al.: Subtype diagnosis, treatment, complications and outcomes of primary aldosteronism and future direction of research: a position statement and consensus of the Working Group on Endocrine Hypertension of the European Society of Hypertension \u0026lowast;. Journal of Hypertension. 38, 1929-1936\u003cem\u003e \u003c/em\u003e(2020). https://doi.org/10.1097/hjh.0000000000002520. \u003c/li\u003e\n\u003cli\u003eFunder JW, Carey RM, Fardella C, et al.: Case Detection, Diagnosis, and Treatment of Patients with Primary Aldosteronism: An Endocrine Society Clinical Practice Guideline. The Journal of Clinical Endocrinology \u0026amp; Metabolism. 93, 3266-3281\u003cem\u003e \u003c/em\u003e(2008). https://doi.org/10.1210/jc.2008-0104. \u003c/li\u003e\n\u003cli\u003eRehan M, Raizman JE, Cavalier E, Don-Wauchope AC, Holmes DT. Laboratory challenges in primary aldosteronism screening and diagnosis. Clinical Biochemistry. 48, 377-387\u003cem\u003e \u003c/em\u003e(2015). https://doi.org/10.1016/j.clinbiochem.2015.01.003.\u003c/li\u003e\n\u003cli\u003eDavidson JS, Chiu WW, Lam L. Overestimation of Aldosterone by Immunoassay in Renal Impairment. Clinical Chemistry. 62, 890-891\u003cem\u003e \u003c/em\u003e(2016). https://doi.org/10.1373/clinchem.2016.255737. \u003c/li\u003e\n\u003cli\u003eHartman D. Plasma Aldosterone: Comparison of a New Automated Assay with a Standard Extraction Method. Clinical Chemistry. 52, 2118-2119\u003cem\u003e \u003c/em\u003e(2006). https://doi.org/10.1373/clinchem.2006.073411. \u003c/li\u003e\n\u003cli\u003eLevey AS, Stevens LA, Schmid CH. A New Equation to Estimate Glomerular Filtration Rate. Annals of Internal Medicine. 150, 609-612\u003cem\u003e \u003c/em\u003e(2009). https://doi.org/10.7326/0003-4819-150-9-200905050-00006. \u003c/li\u003e\n\u003cli\u003eBidlingmaier M, Reincke M, Beuschlein F, et al.: Automated Chemiluminescence-Immunoassay for Aldosterone during Dynamic Testing: Comparison to Radioimmunoassays with and without Extraction Steps. Clinical Chemistry. 52, 1749-1755\u003cem\u003e \u003c/em\u003e(2006). https://doi.org/10.1373/clinchem.2006.068502. \u003c/li\u003e\n\u003cli\u003eRay JA, Kushnir MM, Palmer J, et al.: Enhancement of specificity of aldosterone measurement in human serum and plasma using 2D-LC\u0026ndash;MS/MS and comparison with commercial immunoassays. Journal of Chromatography B. 970, 102-107\u003cem\u003e \u003c/em\u003e(2014). https://doi.org/10.1016/j.jchromb.2014.08.042. \u003c/li\u003e\n\u003cli\u003eEisenhofer G, Kurlbaum M, Peitzsch M, et al.: The Saline Infusion Test for Primary Aldosteronism: Implications of Immunoassay Inaccuracy. The Journal of Clinical Endocrinology \u0026amp; Metabolism. 107, e2027-e2036\u003cem\u003e \u003c/em\u003e(2022). https://doi.org/10.1210/clinem/dgab924. \u003c/li\u003e\n\u003cli\u003eYin Y, Ma C, Yu S, et al.: Comparison of three different chemiluminescence assays and a rapid liquid chromatography tandem mass spectrometry method for measuring serum aldosterone. Clinical Chemistry and Laboratory Medicine (CCLM). 58, 95-102\u003cem\u003e \u003c/em\u003e(2019). https://doi.org/10.1515/cclm-2019-0706. \u003c/li\u003e\n\u003cli\u003eBlocki F, Zierold C, Olson G, et al.: In defense of aldosterone measurement by immunoassay: a broader perspective. Clinical Chemistry and Laboratory Medicine (CCLM). 55, (2017). https://doi.org/10.1515/cclm-2016-0707.\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"Plasma Aldosterone, Liquid chromatography-tandem mass spectrometry, Chemiluminescence assays, Renal function","lastPublishedDoi":"10.21203/rs.3.rs-4336691/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-4336691/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003ePurpose\u003c/h2\u003e \u003cp\u003eCompared with chemiluminescence immunoassay (CLIA), quantification of plasma aldosterone concentration (PAC) by liquid chromatography-tandem mass spectrometry (LC-MS/MS) yields lower values. Whether this difference is exacerbated by a declined glomerular filtration rate (eGFR) is unclear. Therefore, this study aims to assess the impact of renal insufficiency on PAC measured by CLIA using LC-MS/MS as the reference method.\u003c/p\u003e\u003ch2\u003eMethods\u003c/h2\u003e \u003cp\u003eIn subjects with normal or declined estimated glomerular filtration rate (eGFR), PAC were measured by both LC-MS/MS and two different CLIA kits (Mindray and Diasorin).\u003c/p\u003e\u003ch2\u003eResults\u003c/h2\u003e \u003cp\u003e383 patients were included in our study. Among them, there were 71 subjects with eGFR\u0026thinsp;\u0026gt;\u0026thinsp;90 (group one), 79 with eGFR 60\u0026ndash;89 (group two), 108 with eGFR 30\u0026ndash;59 (group three), 51 with eGFR 15\u0026ndash;29 (group four), and 74 with eGFR\u0026thinsp;\u0026lt;\u0026thinsp;15 (group five) ml/min per 1.73m\u003csup\u003e2\u003c/sup\u003e, respectively. In all subjects, PAC measured by CLIA [68.2(37.1-122.1) pg/ml for Mindray, 109.0(68.1\u0026ndash;170.0) pg/ml for Diasorin] were significantly increased compared with those measured by LC-MS/MS [47.2(22.9\u0026ndash;88.7) pg/ml]. The PAC measured by CLIA was positively correlated with that by LC-MS/MS, but the correlation coefficient diminished gradually with eGFR decline. Between LC-MS/MS and Diasorin CLIA kit, the difference of PAC increased with declined eGFR in groups one to five (76.8%, 69.2%, 113.2%, 152.2% and 476.2% for groups one to five, respectively). However, the difference increased only in group five in Mindray CLIA kit (46.4%, 48.1%, 45.7%, 45.0% and 74.9% for group one to five, respectively).\u003c/p\u003e\u003ch2\u003eConclusion\u003c/h2\u003e \u003cp\u003eIn patients with declined renal function, PAC measured by CLIA might be overestimated. Caution is needed in the interpretation of PAC in patients with severe renal impairment. When accurate measurements are required, LC-MS/MS should be considered.\u003c/p\u003e","manuscriptTitle":"Comparison of chemiluminescence immunoassay with LC-MS/MS in the determination of plasma aldosterone concentration in patients with declined renal function","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-05-07 18:50:23","doi":"10.21203/rs.3.rs-4336691/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"3a2f9197-5742-47fe-a5c0-be1bca49640c","owner":[],"postedDate":"May 7th, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2024-05-07T18:50:25+00:00","versionOfRecord":[],"versionCreatedAt":"2024-05-07 18:50:23","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-4336691","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-4336691","identity":"rs-4336691","version":["v1"]},"buildId":"qtupq5eGEP_6zYnWcrvyt","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}