Comparisons of renin-angiotensin-aldosterone levels measured by chemical luminescence immunoassay and liquid chromatography-tandem mass spectrometry in hypertensive patients under different pathophysiological conditions

This study aimed to compare measurements of the renin-angiotensin-aldosterone system (RAAS) components by liquid chromatography-tandem mass spectrometry (LC-MS/MS) and chemiluminescent immunoassay (CLIA) in hypertensive patients with different gender, position and renal function. EDTA plasma from 100 hypertensive patients who completed postural test were included. Aldosterone (PAC), renin (PRC, using Autobio CLIA microparticles kit; DRC, using LIAISON Direct Renin CLIA kit), angiotensin I and II (AngI and AngII), 18-hydroxycorticosterone (18-OHB) and 18-hydroxycortisol (18-OHF) were measured. Median PAC CLIA was 46.0% higher ( P < 0.01) than PAC LC-MS/MS . Median PAC CLIA , 18-OHB LC-MS/MS and 18-OHF LC-MS/MS were higher ( P < 0.01) in patients with renal dysfunction compared with patients with normal renal function, whereas median PAC LC-MS/MS did not show a significant difference between the two groups. Both median PRC CLIA and DRC CLIA were higher ( P < 0.01) in male patients compared with female patients. PAC LC-MS/MS , PAC CLIA , PRC CLIA and DRC CLIA all showed good consistency in response to an assumption of upright posture. Close ( P < 0.01) correlations were observed between PAC CLIA and PAC LC-MS/MS , between PRC CLIA and DRC CLIA , between AngII LC-MS/MS and PRC CLIA , and between AngII LC-MS/MS and DRC CLIA . LC-MS/MS is a reliable assay for measurement of the RAAS components in hypertensive patients under different pathophysiological conditions.