化学发光法检测输血前梅毒特异性抗体复查策略的研究

The Rechecking Strategy of Detecting the Specific Antibody Against Treponema Pallidum in Patients before Blood Transfusion

目的探讨化学发光法(chemiluminescence immunoassay,CLIA)完全替代酶联免疫吸附法(Enzyme linked immunosorbent assay,ELISA)进行患者输血前梅毒特异性抗体检测的可行性,并制定化学发光法检测弱反应性标本的复查策略。方法首先采用CLIA试剂筛选出梅毒特异性抗体结果 S:CO(absorbance signal of sample∶cutoff value,即样本吸光度值∶临界值)>0.30的血清样本,再采用2种ELISA试剂复查,最后以梅毒螺旋体血凝实验(treponema pallidum haemagglutination assay,TPHA),对3种试剂均在临界值以上(S/CO≥0.80)或至少1种试剂临界值以上的标本进行确认。评估检测效果,制定复查策略。结果应用CLIA试剂从5 000份标本中筛查出梅毒特异性抗体S/CO>0.30的血清样本141份,经2种ELISA试剂复查后,CLIA检测结果S/CO≥0.5、ELISA检测结果≥0.8的阳性率为92.5%;3种试剂或至少1种试剂检测结果S/CO≥0.8的72份标本,经TPHA确认阳性58份,其中2份标本CLIA检测结果0.8>S/CO>0.60。结论 CLIA与ELISA方法检测梅毒特异性抗体存在一定不符合性;建议对CLIA检测结果 S/CO>0.50标本采用ELISA联合检测,对S/CO>0.60的标本采用梅毒螺旋体明胶颗粒凝集试验(Treponema pallidum particle assay,TPPA)或TPHA法确证。

Objective To investigate the feasibility of chemiluminescence immunoassay （CLIA） in enzyme linked immunosorbent assay （ELISA） to detect the specific antibodies against Treponema pallidum in patients before blood transfusion, and to develop a rechecking strategy for the weak positive samples by CLIA. Methods The samples were selected by CLIA for antibodies against T. pallidum S/CO（absorbance signal of sample： cutoff value）〉0. 30. Thereafter, the samples were rechecked by ELISA kits from two companies. The samples of which the antibody test results was above the cut-off value （S/CO〉0. 30） either by all the three reagents or one reagent at least was confirmed by T. pallidum haemagglutination assay （TPHA）. Consequently, the assay effect was evaluated and the rechecking strategy was determined. Results 141 samples of which the assay results of antibodies against T. pallidum were S/CO〉0. 30 by CLIA were selected for the study from 5 000 collected sera samples. The positive rate in the 141 sera samples was 92.5% rechecked by the two deferent ELISA reagents （S/CO≥0. 8） and CLIA（S/CO^O. 5）. Among the 72 samples of which the assay results were S/CO≥0. 8 detected either by all the three reagents or one reagent at least, 58 samples were definitely positive when confirmed by TPHA. However, the results of 2 samples from these 58 samples assayed by CLIA were 0. 8〉S/CO〉0. 60. Conclusions There is inconsistence of the results between the two existing methods of CLIA and ELISA. The results suggest that ELISA should be combined with CLIA to detect the samples with S/CO more than 0. 50 by CLIA. T. pallidum particle assay （TPPA） or TPHA should be performed to confirm the samples with S/CO more than 0. 60 by CLIA.