Füzéry Anna K, Raizman Joshua E, Goudreau Bobbi Lynn, Moses Karin, Niemann Keri, Park Janice, Cembrowski George S
Department of Laboratory Medicine and Pathology, University of Alberta, Edmonton, Alberta, Canada; Alberta Health Services, Edmonton, Alberta, Canada.
Department of Laboratory Medicine and Pathology, University of Alberta, Edmonton, Alberta, Canada; Alberta Health Services, Edmonton, Alberta, Canada.
Clin Biochem. 2017 Oct;50(15):851-857. doi: 10.1016/j.clinbiochem.2017.05.015. Epub 2017 Jun 3.
BD Canada recently released a blood collection tube with a novel mechanical separator called the Barricor. We evaluated this tube as an alternate sample type for cardiac troponin I (cTnI) testing using the Beckman Coulter AccuTnI+3 assay.
3014 paired patient specimens (Barricor, plasma separator tube or PST) were obtained from the emergency departments and cardiac care units of nine hospitals in and around Edmonton, Alberta. After centrifugation, each plasma sample was analyzed for cTnI using the Beckman Coulter AccuTnI+3 assay. In addition, selected samples were analyzed multiple times within a single run or over 4-5days to generate imprecision data for the assay.
Repeatability and within-laboratory studies revealed an imprecision of <10% at concentrations above 0.025μg/L for the Barricor as well as BD's traditional PST. Paired patient sample comparisons over the full range of the assay yielded linear regression slopes ranging from 0.956 to 1.011 and Pearson correlation coefficients ranging from 0.993 to 0.999. At a lower range of results closer to the manufacturer's 99th percentile cutoffs correlation was slightly worse, but still acceptable, with linear regression slopes ranging from 0.967 to 1.211 and Pearson correlation coefficients ranging from 0.983 to 0.987. Notably, at these lower concentrations the agreement between individual PST and Barricor results worsened with decreasing cTnI concentration. Differences between pairs of results became particularly large (-50 to +400%) at PST cTnI concentrations ≤0.015μg/L. Closer inspection of the data around the 0.02 and 0.04μg/L 99th percentile cutoffs revealed a number of discordances between PST and Barricor results, with at least some of these attributable to false elevations in the PST results.
Together, our results suggest that the Barricor blood collection tube is good alternative to the traditional PST for cTnI testing using the AccuTnI+3 assay. The Barricor appears to minimize spurious, nonreproducible, and false elevations in cTnI results for a subset of patients but additional studies are needed to determine if it reduces overall false elevations. cTnI results below 0.04μg/L may still be of questionable accuracy even with the use of this new tube.
BD加拿大公司最近推出了一种带有新型机械分离器Barricor的采血管。我们使用贝克曼库尔特AccuTnI + 3检测法评估了该采血管作为心肌肌钙蛋白I（cTnI）检测的替代样本类型。
从艾伯塔省埃德蒙顿及其周边地区九家医院的急诊科和心脏监护病房获取了3014对患者标本（Barricor采血管、血浆分离管或PST）。离心后，使用贝克曼库尔特AccuTnI + 3检测法对每个血浆样本进行cTnI分析。此外，对选定的样本在单次运行内或4 - 5天内进行多次分析，以生成该检测法的不精密度数据。
重复性和实验室内部研究表明，对于Barricor采血管以及BD公司的传统PST，在浓度高于0.025μg/L时，不精密度<10%。在整个检测范围内对成对患者样本进行比较，得到的线性回归斜率范围为0.956至1.011，皮尔逊相关系数范围为0.993至0.999。在更接近制造商第99百分位数临界值的较低结果范围内，相关性稍差，但仍可接受，线性回归斜率范围为0.967至1.211，皮尔逊相关系数范围为0.983至0.987。值得注意的是，在这些较低浓度下，随着cTnI浓度降低，单个PST和Barricor采血管结果之间的一致性变差。当PST的cTnI浓度≤0.015μg/L时，成对结果之间的差异变得特别大（-50%至 +400%）。对0.02和0.04μg/L第99百分位数临界值附近的数据进行更仔细检查发现，PST和Barricor采血管结果之间存在一些不一致，其中至少有一些归因于PST结果中的假升高。
总体而言，我们的结果表明，对于使用AccuTnI + 3检测法进行cTnI检测，Barricor采血管是传统PST的良好替代品。Barricor采血管似乎能将一部分患者cTnI结果中的假性、不可重复和假升高降至最低，但还需要进一步研究以确定它是否能减少总体假升高。即使使用这种新采血管，cTnI结果低于0.04μg/L时的准确性可能仍值得怀疑。
