丙型肝炎病毒抗体化学发光免疫分析法 ≥ 95%阳性预测值最佳吸光度/临界值建立方法学和重要性探讨

Methodology of the optimal signal-to-cutoff value by chemiluminescence immunoassay of the positive predictive value of hepatitis C antibody ≥ 95% and the discussion of importance

摘要

目的  确定丙型肝炎病毒（hepatitis C virus,HCV）抗体阳性预测值 ≥ 95%的最佳吸光度/临界值（signal-to-cutoff，S/CO），确定首都医科大学附属北京地坛医院实验室医学决定水平，为探索不同系统丙型肝炎病毒抗体检测试剂95%阳性置信区间建立方法学。方法  收集2021年7月至2022年2月门诊及住院患者进行化学发光免疫分析法（chemiluminescence analysis,CLIA）初筛检测同时进行HCV RNA检测的血浆样本共282例，其中抗体初筛有反应性（S/CO ≥ 1）样本252例，阴性样本30例，进行重组免疫印记试验（recombinant immunoblot assay,RIBA）并查阅其HCV RNA检测结果，通过受试者工作特征(receiver operating characteristic,ROC)曲线得到预测本实验室阳性预测值 ≥ 95%时HCV感染的抗体S/CO值。结果  初筛为阴性的30例样本双重确证试验结果均为阴性；排除16例HCV感染史不明确的样本，丙型肝炎病毒抗体S/CO ≥ 1的236例样本经双重确证试验得到真阳性样本188例，阴性样本48例，经ROC曲线分析，本实验室阳性预测值 ≥ 95%时，本实验室抗体S/CO值为7.83，灵敏度为93.09%，特异度为95.83%，曲线下面积（area under the curve,AUC）为0.98（P < 0.000 1）。结论  为临床提供本实验室阳性预测值 ≥ 95%时HCV感染抗体的S/CO值以协助临床诊疗。

Abstract

Objective  To determine the optimal signal-to-cutoff (S/CO) value of the positive predictive value of hepatitis C virus  (HCV) antibody ≥ 95%,and to determine the medical decision level of the laboratory and to establish the methodology for exploring the 95% positive confidence intervals for different systems of HCV antibody detection reagents. Methods  From July 2021 to February 2022,a total of 282 plasma samples from outpatients and inpatients in Beijing Ditan Hospital,Capital Medical University were subjected to both the initial screening of chemiluminesent immunoassay (CLIA) and HCV RNA testing.Among the samples,252 showed reactivity in the antibody initial screening (S/CO ≥ 1),while 30 samples tested negative; supplemental confirmation test of recombinant immunoblot assay (RIBA) was performed and the results of HCV RNA were consulted. The antibody S/CO value of HCV infection was obtained by receiver operating characteristic  (ROC) curve when the positive predictive value in our laboratory was ≥ 95%.  Results  The 30 samples tested negative in the initial screening also showed negative results for HCV RNA testing and RIBA. Excluding 16 cases with unclear history of HCV infection,among 236 samples with HCV antibody S/CO ≥ 1,188 samples were true positive and 48 samples were negative. ROC analysis showed that the optimal S/CO value was 7.83,the sensitivity was 93.09%,the specificity was 95.83% and the area under the curve (AUC) was 0.98. (P < 0.000 1). Conclusion  It is helpful for clinical diagnosis and treatment to provide the antibody S/CO value of HCV infection when the positive predictive value was ≥ 95% in our laboratory.

关键词

丙型肝炎病毒抗体 / 重组免疫印迹试验 / 受试者工作特征曲线 / 阳性预测值

Key words

hepatitis C virus antibody / recombinant immunoblotting assay / receiver operating characteristic curve / positive predictive value