实时聚合酶链反应技术检测妊娠晚期孕妇B族溶血性链球菌的多中心研究

A multi-center study on realtime polymerase chain reaction assay for group B Streptococcus in pregnant ;women

目的探讨实时聚合酶链反应（polymerase chain reaction，PCR）技术检测妊娠晚期孕妇B族溶血性链球菌（group B Streptococcus，GBS）的准确性。方法本研究为多中心研究。选择2009年3月1日至12月31日在北京大学第一医院妇产科、首都医科大学附属北京妇产医院产科和北京大学第三医院妇产科产前保健的妊娠35～37周孕妇，取阴道下1/3分泌物及肛周分泌物，采用常规细菌培养法及实时PCR方法进行GBS检测。采用基因测序作为矫正方法，分析实时PCR方法检测GBS的敏感性和特异性。结果（1）3家医院共收集1395份标本，细菌培养法检测GBS阳性40例（2.9%），实时PCR方法检测GBS阳性114例（8.2%）。（2）仅实时PCR方法检测GBS阳性者77例，采用事先设计好的第2对引物扩增后进行测序，检测鉴定为GBS序列的共66例，11例为非GBS。（3）以细菌培养法加测序法校正作为金标准，实时PCR方法检测GBS的敏感性为97.2%（103/106），特异性为99.1%（1278/1289）。常规细菌培养法漏诊率62.3%（66/106）。（4）细菌培养法加测序法校正3家医院孕妇妊娠晚期GBS携带率为7.6%（106/1395）。结论实时PCR方法检测GBS具有较高的敏感性和特异性，有望成为妊娠晚期常规检测GBS的方法。

Objective To evaluate the accuracy of realtime polymerase chain reaction （PCR） assay in the detection of group B Streptococcus （GBS） in pregnant women. Methods Samples were collected from 1 395 women at 35-37 weeks of gestation from March 1 to December 31, 2009 at three hospitals in Beijing. Samples were obtained from the lower one third vaginal wall and perianal area and tested for GBS using standard culture and PCR. Standard culture and gene analysis for GBS were applied as the gold standard, and the sensitivity and specificity of the rapid assay were determined. Results Of the 1 395 women qualified for PCR testing, 40（2.9%） were identified as GBS positive on the basis of the results of specimen culture, compared to 114 （8.2%） on the basis of PCR assay. The culture was negative and the PCR positive in 77 patients. The results which were not in agreement using the two tests were evaluated by the gene analysis for GBS. Among the 77 samples which were GBS positive by PCR, 66 samples were determined as GBS positive by gene analysis. The sensitivity of the PCR assay was 97.2%（103/106） and specificity was 99.1%（1 278/1 289）, the maternal GBS colonization was 7.6%（106/1 395）. Conclusions Realtime PCR assay allows rapid and reliable detection of GBS in last trimester with high sensitivity and specificity.