Smith Joe S, Varga Anita, Schober Karsten E
Department of Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA, United States.
Department of Biomedical Sciences, College of Veterinary Medicine, Iowa State University, Ames, IA, United States.
Front Vet Sci. 2020 Aug 27;7:531. doi: 10.3389/fvets.2020.00531. eCollection 2020.
Multiple cardiac troponin I (cTnI) immunoassays are commercially available. Overall, assays have not been standardized, and inter-assay differences in the detection of the analyte cardiac troponin I can be clinically relevant. To compare the diagnostic accuracy of the commercially available Abbott i-STAT®1 cTnI immunoassay (i-STAT) and the previously validated ADVIA Centaur TnI-Ultra immunoassay (Centaur) in cattle. There will be significant differences in bovine serum cTnI results measured by the Centaur and i-STAT methods. Ten dairy cows with experimentally induced myocardial injury due to monensin administration. Thirty apparently healthy dairy cows with no history of monensin exposure served as controls. Blood was collected at various time points after administration of a single dose of monensin (20 to 50 mg/kg) via orogastric tube. A total of 112 blood samples were collected. Cardiac TnI concentration was analyzed with the two methods and the association between methods analyzed via linear regression. Bland-Altman analysis to evaluate agreement between methods was performed on samples divided into groups (cTnI < 1.0 ng/mL and cTnI ≥ 1.0 ng/mL). Analyzer results were linearly correlated with each other ( = 0.931). Samples with cTnI concentrations <1.0 ng/mL had a bias of -0.13 ± 0.20 ng/mL and samples with cTnI concentrations >1.0 ng/mL had a bias of -9.81 ± 13.26 ng/mL. The results of this study reveal that cTnI concentrations determined with the i-STAT are systematically lower compared to the concentrations determined by the Centaur.
有多种心肌肌钙蛋白I（cTnI）免疫测定法可供商业使用。总体而言，这些测定法尚未标准化，并且在分析物心肌肌钙蛋白I的检测中，不同测定法之间的差异可能具有临床相关性。为了比较市售的雅培i-STAT®1 cTnI免疫测定法（i-STAT）和先前经过验证的ADVIA Centaur TnI-Ultra免疫测定法（Centaur）在牛中的诊断准确性。通过Centaur和i-STAT方法测量的牛血清cTnI结果将存在显著差异。十头因服用莫能菌素而导致实验性心肌损伤的奶牛。三十头无莫能菌素接触史的明显健康奶牛作为对照。通过口胃管单次给予莫能菌素（20至50mg/kg）后，在不同时间点采集血液。总共采集了112份血样。用这两种方法分析心肌肌钙蛋白I浓度，并通过线性回归分析方法之间的关联。对分为两组（cTnI<1.0 ng/mL和cTnI≥1.0 ng/mL）的样本进行Bland-Altman分析以评估方法之间的一致性。分析仪结果彼此线性相关（ = 0.931）。cTnI浓度<1.0 ng/mL的样本偏差为-0.13±0.20 ng/mL，cTnI浓度>1.0 ng/mL的样本偏差为-9.81±13.26 ng/mL。本研究结果表明，与Centaur测定的浓度相比，i-STAT测定的cTnI浓度系统性地更低。
