Christenson R H, Apple F S, Morgan D L, Alonsozana G L, Mascotti K, Olson M, McCormack R T, Wians F H, Keffer J H, Duh S H
Department of Pathology, University of Maryland School of Medicine, Baltimore 21201, USA.
Clin Chem. 1998 Jan;44(1):52-60.
We evaluated the ACCESS cardiac troponin I (cTnI) immunoassay as a marker for myocardial infarction (MI). Total imprecision was 6.0% to 13.5%, the minimum detectable concentration was 0.007 microg/L, and the limit of quantitation was 0.046 microg/L. Comparison of cTnI measurement between the ACCESS and Stratus systems (n = 114) showed a proportional difference: ACCESS cTnI = 0.0996 Stratus cTnI + 0.049 microg/L (r = 0.811). Fifty-nine of 61 ambulatory patients without cardiac symptoms had no detectable cTnI (95% range, 0.00 to 0.025 microg/L). The optimum cutoff for discriminating MI (n = 289, 45 with MI) was 0.15 microg/L by receiver operator characteristic curve analysis; at this cutoff, the ACCESS cTnI assay showed a sensitivity of 88.9% (95% CI, 79.7-98.1%) and specificity of 91.8% (95% CI, 88.4-95.2%). The ACCESS cTnI assay results showed 89.4% and 93.0% concordance with the MB isoenzyme of creatine kinase (CK-MB) mass and Stratus cTnI results, respectively, for classification of patients with suspected MI. The ACCESS cTnI assay appears to show sensitivity and specificity comparable with those of both CK-MB mass and Stratus cTnI assays for the diagnosis of MI in patients presenting within 12 h of onset of symptoms.
我们评估了ACCESS心肌肌钙蛋白I（cTnI）免疫测定法作为心肌梗死（MI）标志物的性能。总不精密度为6.0%至13.5%，最低检测浓度为0.007μg/L，定量限为0.046μg/L。ACCESS系统和Stratus系统之间的cTnI测量结果比较（n = 114）显示出比例差异：ACCESS cTnI = 0.0996 Stratus cTnI + 0.049μg/L（r = 0.811）。61例无心脏症状的门诊患者中有59例检测不到cTnI（95%范围，0.00至0.025μg/L）。通过受试者操作特征曲线分析，鉴别MI（n = 289，45例为MI）的最佳临界值为0.15μg/L；在此临界值下，ACCESS cTnI测定法的灵敏度为88.9%（95%CI，79.7 - 98.1%），特异性为91.8%（95%CI，88.4 - 95.2%）。对于疑似MI患者的分类，ACCESS cTnI测定结果与肌酸激酶（CK - MB）质量的MB同工酶和Stratus cTnI结果的一致性分别为89.4%和93.0%。对于症状发作12小时内就诊的患者，ACCESS cTnI测定法在诊断MI时的灵敏度和特异性似乎与CK - MB质量测定法和Stratus cTnI测定法相当。
