探索一种能降低血液抗-HIV筛查假阳性率的有效路径

An effective path to reduce the false positive rate of blood anti-HIV screening

目的将无偿献血者血液进行艾滋病病毒(HIV)抗体和核酸检测,探索一条既能有效降低抗-HIV筛查假阳性率,又能节约有限资源的可行路径。方法收集山西省血液中心2017年1-12月80 235份无偿献血者血液标本,使用两种路径检测并评估新筛查路径的有效性和可行性。统计学分析采用SPSS 17.0软件,应用χ2检验比较两路径阳性预测值及报废率。结果抗-HIV检测有反应性的标本数为187份。通过路径1,此187份标本送疾病预防控制中心(CDC)进行确证,确证后阳性标本数为36份,其阳性预测值(PPV)为19.3%(36/187);通过路径2,仅有52份标本送CDC进行确证,135份标本直接做NAT试验,确证后阳性标本数为36份,阳性预测值为69.2%(36/52)。两路径阳性预测值比较,差异有统计学意义(χ2=48.281,P<0.05)。1份抗-HIV检测无反应的样本,经NAT检测为核酸阳性,其捐献者经过随访及后续试验证明是1例HIV窗口期感染者。采用路径1,血液制品报废率为2.3‰(187/80 235),而路径2极大地降低了报废率,为0.65‰(52/80 235)。两条路径报废率比较,差异有统计学意义(χ2=76.369,P<0.05)。结论路径2对于抗-HIV检测敏感性、特异性好,同时还能降低成本,节约时间,可作为一种降低血液抗-HIV筛查假阳性率的有效路径。

Objective To test HIV antibody and nucleic acid in blood of voluntary donors for exploration of an effective path to reduce the false-positive rate of blood anti-HIV screening and to save the limited resources.Methods A total of 80 235 voluntary donors’samples were collected in the study from Shanxi blood center during January and December 2017.All of the samples were screened through HIV antibody and nucleic acid methods followed by the analysis of effectiveness.SPSS17.0 software was used for statistical analysis,andχ2 test was used to compare the positive predictive value and the rejection rate of the two.Results There were 187 samples with anti-HIV testing reacted.By using path one,187 reacted samples were sent to CDC,and 36 samples were confirmed as HIV positive(PPV=19.3%,36/187).By using path two,only 52 samples were sent to CDC for confirmation,and 135 samples were tested by NAT directly,with 36 samples confirmed as HIV positive(PPV=69.2%,36/52).The positive predictive values of the two pathways were significantly different(χ2=48.281,P<0.05).One non-reactive sample of anti-HIV testing was HIV-positive by NAT,and the donor was confirmed to be a window-stage HIV infection by follow-up visit and testing.With path one,the rejection rate of blood products was 2.3‰(187/80235),while path two greatly reduced the rejection rate to 0.65‰(52/80235).The statistical difference was significant(χ2=76.369,P<0.05).Conclusion Path two is a sensitive and specific way for anti-HIV testing,and can reduce costs and save time,which is effective to reduce the false-positive rate of blood anti-HIV screening.