Analytical evaluation of the new Beckman Coulter Access high sensitivity cardiac troponin I immunoassay

Background: This study was aimed to evaluate the analytical performance of the novel chemiluminescent and fully-automated Beckman Coulter Access hsTnI high-sensitivity immunoassay for measurement of cardiac troponin I (cTnI). Methods: The study, using lithium heparin samples, included assessment of limit of blank (LOB), limit of detection (LOD), functional sensitivity, linearity, imprecision (within run, between-run and total), calculation of 99th percentile upper reference limit (URL) in 175 healthy blood donors (mean age, 36 +/- 12 years; 47% women) and comparison with two other commercial cTnI immunoassays. Results: The LOB, LOD and functional sensitivity of Access hsTnI were 0.14, 0.34 and 1.35 ng/L, respectively. The within-run, between-run and total imprecision was 2.2%-2.9%, 4.6%-5.4%, and 5.4%-6.1%, respectively. The linearity was excellent in the range of cTnI values between 0.95 and 4195 ng/L (r = 1.00). The 99th percentile URL was 15.8 ng/L. Measurable cTnI values were found in 173/175 healthy subjects (98.9%). Good agreement of cTnI values was found with AccuTnI+3 (r = 0.97; mean bias, -9.3%), whereas less satisfactory agreement was found with Siemens Dimension Vista cTnI (r = 0.95; mean bias, -55%). Conclusions: The results of our evaluation of the Beckman Coulter Access hsTnI indicate that the analytical performance of this fully-automated immunoassay is excellent.