Ultrio和Ultrio plus 2种核酸试剂对献血者HCV RNA筛查的一致性分析

Comparison of Ultrio and Ultrio Plus NAT assays for screening of HCV RNA among blood donors

目的追踪分析Ultrio和Ultrio plus 2种核酸试剂对抗-HCV阳性献血者血液标本筛查结果不一致的原因,并评价此2种核酸试剂检测HCV RNA的一致性。方法 6 254份ORTHO抗-HCV ELISA阴性及158份ORTHO抗-HCV ELISA阳性的无偿献血者血液标本,应用Procleix TIGRIS核酸检测系统的Ultrio、Ultrio plus试剂分别进行核酸筛查,对2种核酸试剂筛查HCV RNA结果不一致的献血者进行追踪,重新采集追踪标本补充Procleix Ultrio Elite、HCV Blot、HCV RNA定量检测,综合分析此2种核酸筛查试剂检测HCV RNA的临床灵敏度。结果 6 254份ORTHO抗-HCV ELISA阴性标本Ultrio、Ultrio plus试剂均未检出HCV RNA反应性。158份ORTHO抗-HCV ELISA阳性标本Ultrio反应性48例,Ultrio plus反应性51例,2种核酸试剂均为反应性47例。2种核酸试剂检测结果高度线性相关(Spearman相关系数rs=0.940,P<0.001),Kappa检验显示一致性极强(Kappa=0.940,P<0.001),配对卡方检验差异无统计学意义。6例核酸检测不一致标本分别为:2例Ultrio+/Ultrio plus-中1例HCV Blot阳性、1例HCV Blot可疑,1例HCV病毒核酸定量检测有结果;4例Ultrio-/Ultrio plus+标本中HCV Blot阳性3例、阴性1例,HCV病毒核酸定量检测3例有结果。追踪标本分析:1例Ultrio+/Ultrio plus-标本检测结果HCV Blot确证试验可疑,Ultrio Elite无反应性、HCV病毒核酸定量检测无结果;2例Ultrio-/Ultrio plus+追踪标本Ultrio Elite检测均无反应性,HCV Blot均阳性。结论 Ultrio与Ultrio plus核酸试剂检测HCV RNA一致性好,对临近检出限的低病毒载量标本均存在概率性检出。

Objective To analyze the performance of Ultrio plus and Ultrio for screening of HCV RNA by tracking samples with discordant nucleic acid test results in anti-HCV positive blood donors.Methods A total of 6254 ORTHO anti-HCV ELISA negative donor samples and 158 anti-HCV positive donor samples were tested by Ultrio and Ultrio plus on Procleix TIGRIS nucleic acid detection system. Blood donors with inconsistent HCV RNA results screened by two NAT reagents were followed up. The followed-up samples were collected again and retested by Procleix Ultrio Elite, HCV confirmatory test and quantitative detection of HCV RNA.The clinical sensitivity of two NAT reagents for detection of HCV RNA Was comprehensively analyzed.Results No HCV RNA was detected in 6254 ORTHO anti-HCV ELISA negative samples. There were 48 cases of Ultrio reactivity, 51 cases of Ultrio plus reactivity, and 47 cases of both nucleic acid reagents in 158 ORTHO anti-HCV ELISA positive samples. Good correlation between two reagents results(Spearman correlation coefficient RS=0.940, P<0.001). The Kappa statistic for results of two reagents was 0.940, indicating strong concordance(Kappa value=0.940, P<0.001). The McNemar-Bowker test revealed no statistical significance(McNemar-Bowker, P>0.05). Inconsistent sample analysis: Among 2 Ultrio+/Ultrio plus-samples, 1 HCV Blot confirmed test positive, 1 HCV Blot suspicious, 1 HCV virus nucleic acid quantitative test had result;1 HCV Blot confirmed test negative, 3 HCV Blot positive in 4 Ultrio-/Ultrio plus-samples. 3 HCV virus nucleic acid quantitative test had results. Follow-up sample analysis: 1 Ultrio+/Ultrio plus-samples HCV Blot was suspicious, while Ultrio Elite was negative, HCV virus nucleic acid quantitative hadn’t result. 2 Ultrio-/Ultrio plus + samples Ultrio Elite were non-reactive, and HCV Blot were positive.Conclusion Ultrio and Ultrio plus reagents have good consistency in detecting HCV RNA, and there are probabilistic detections for low viral load samples near the detection limit.