化学发光微粒子免疫分析法检测孕妇梅毒特异性抗体的应用评价

Evaluation of the Chemiluminescent Microparticle Immunoassay for Detection of Specific Antibodies to Syphilis in Pregnant Women

目的探讨化学发光微粒子免疫分析法(CMIA)检测孕妇血清中梅毒螺旋体特异性抗体(TP-Ab)的应用价值。方法150314例妊娠期妇女血清标本采用CMIA检测TP-Ab,S/CO≥0.5用TPPA及ELISA检测;以TPPA为确证方法,比较不同S/CO值CMIA与TPPA的符合率。CMIA与TPPA检测结果不一致的标本进行梅毒WB检测。分析CMIA不同cutoff值筛查妊娠期妇女血清TP-Ab的灵敏度、特异性、阳性预测值及阴性预测值,绘制ROC曲线。结果CMIA检测孕妇TP-Ab阳性检出率为1.06%,TPPA阳性检出率为0.84%,差异有统计学意义(P<0.05)。近3年妊娠期妇女梅毒阳性检出率逐年减低,差异有统计学意义(P<0.05)。以TPPA为确证方法,CMIA检测结果S/CO在1.01~2.00之间与TPPA的符合率仅40.21%,而S/CO≥5.0时与TPPA的符合率可达98.98%。CMIA与TPPA结果不一致的298例标本进行WB检测,结果表明TPPA与WB两种方法的一致性较好(Kappa=0.866,P=0.227)。CMIA检测妊娠期妇女血清TP-Ab的ROC曲线下面积为0.980(95%CI:0.975-0.984),最佳cutoff值为2.105,此时敏感度为94.3%,特异性为91.3%。结论基于孕妇梅毒漏检、误检的高危害性,建议将妊娠期妇女雅培CMIA检测结果梅毒抗体S/CO≥0.5的标本均进行TPPA复检,以确保检测结果的准确性。

Objective To investigate the chemiluminescent microparticle immunoassay(CMIA)for detecting specific antibodies to syphilis(TP-Ab)in pregnant women.Methods CMIA first screened 150314 serum samples of pregnant women;samples with S/CO≥0.5 were further detected by TPPA and ELISA.TPPA was used as the confirming test.The coincidence rates of CMIA and TPPA were compared.The samples with the inconsistent results by CMIA and TPPA methods were verified by Western blot(WB).The ROC curve of CMIA detecting the TP-Ab in pregnant women serum was drawn.Results The positive TP-Ab rates in pregnant women serum measured by CMIA and TPPA were 1.06%and 0.84%,respectively(P<0.05).In the last three years,the positive TP-Ab rates in pregnant women serum were decreased,and the difference was significant(P<0.05).The coincidence rates of CMIA and TPPA were 40.21%for samples with S/CO of 1.01-2.00,but 98.98%for samples with S/CO≥5.0.In 298 samples with the inconsistent results by CMIA and TPPA,WB method showed that TP-Ab results detected by TPPA and WB were in good agreement(Kappa=0.866,P=0.227).ROC analysis showed that the area under the curve(AUC)of TP-Ab in pregnant women serum detected by CMIA was 0.980(95%CI:0.975-0.984).The optimal cutoff value was 2.105,with 94.3%sensitivity and 91.3%specificity.Conclusion To ensure the test accuracy,the samples with S/CO≥0.5 first detected in pregnancy by Abbott CMIA should be validated by TPPA due to the high risk of syphilis in pregnancy.