基于抗-TP检测结果细化反应性献血者屏蔽策略的研究

Study on blood donor deferral strategy by analyzing anti-TP test results

目的探讨现行献血者屏蔽策略中对抗-TP ELISA反应性献血者实施屏蔽的准确性和适宜性。方法使用2种不同的抗-TP ELISA试剂常规检测后的标本,进行TPPA确证试验。根据抗-TP ELISA初筛结果及确证结果对双试剂反应性和单试剂反应性献血者检测数据进行分析和整理,从而判定献血者真阳性的可能性。结果共收集抗-TP ELISA反应性的献血者血液标本共1 624份,其中包括双试剂反应性标本1 467份,单试剂反应性标本77份和80份。双试剂反应性标本中,确证阳性1 254份,阳性预期值85.48%;双试剂反应性标本确证为真阳性的可能性与S/CO值的高低相关,试剂1和2的S/CO值≥13和17时,阳性预期值分别为98.56%和99.13%,明显较S/CO值≥1时高。确证阳性的单试剂反应性标本中,试剂1确证阳性2份,试剂2确证阳性3份,阳性预期值分别为2.60%和3.75%。而单试剂反应性标本无高S/CO值的特征。结论高S/CO值的抗-TP ELISA双试剂反应性献血者真阳性可能性高,宜永久屏蔽;TPPA试验可有效辅助单试剂反应性献血者筛选出真阳性。现行的献血者屏蔽策略可能需要补充确证实验和献血者追踪检测等措施方能更精确地屏蔽真阳性献血者,保障血液安全。

Objective To discuss the reliability and applicability of the current blood deferral strategy concerning anti-TPreactive blood donors(by ELISA). Methods TPPA confirmatory test was performed on the samples routinely detected by two different anti-TP ELISA reagents(reagent 1 and reagent 2), and the test data of dual reagent reactive and one reagent reactive blood donors were analyzed to determine the possibility of true positivity. Results 1 624 anti-TP reactive samples(by ELISA) were collected, among which 1 467 were dual reagent reactive, 77 were reagent 1 reactive, and 80 were reagent 2 reactive. TPPA results showed that the positive predictive value(PPV) of dual reactive samples was 85.48%. Samples with high S/CO value(reagent 1≥13 and/or reagent 2 >17) were more likely to be true positive, with the PPV at 98.56%(reagent 1) and 99.13%(reagent 2), respectively, which were significantly higher than that when the S/CO value was≥1. Among the samples reactive to one reagent, 2 were confirmed positive in reagent 1 and 3 in reagent 2, with the PPV at 2.60% and 3.75% respectively, and had no correlation with high S/CO value. Conclusion Dual-reagent reactive donors with high S/CO value showed high possibility of true positivity, therefore should be deferred. TPPA test is helpful to identify true positivity in one-reagent reactive donors. Confirmatory test and follow-up should be a supplement to the current blood donor deferral strategy to ensure blood safety.