围产期孕妇B群链球菌三种筛查方法的评估

Evaluation of Three Screening Methods for Group B Streptococci in Perinatal Women

目的评价Xpert GBS LB法、免疫层析法和普通培养法在围产期孕妇B群链球菌(group B streptococcus, GBS)筛查中的诊断效能及一致性。方法收集35~37周孕妇的生殖道或直肠拭子标本1063份,分别应用显色肉汤增菌培养法、Xpert GBS LB法、免疫层析法和普通培养法进行检测。以显色肉汤增菌培养法为"金标准",评价其他3种检测方法诊断效能并比较其检测结果的一致性。结果 1063例围产期孕妇生殖道或直肠标本使用Xpert GBS LB法检出阳性者251例(23.61%),免疫层析法检出阳性者261例(24.55%),普通培养法检出阳性者193例(18.16%)。与"金标准"比较,Xpert GBS LB法和普通培养法具有极高的一致性,免疫层析法的一致性中度。普通培养法特异性最高,Xpert GBS LB敏感性最高,而免疫层析法的敏感性和特异性均较差。结论 3种方法均适用于临床GBS筛查,其中Xpert GBS LB法和普通培养法与"金标准"显色肉汤增菌培养法具有极强的一致性,而Xpert GBS LB法还具有更高的敏感性,适用于GBS感染的快速诊断。

Objective To evaluate the diagnostic efficacy and consistency of Cepheid Xpert GBS LB, immunochromatography and general culture in the screening of group B streptococci in perinatal women. Methods A total of 1063 cases of genital rectal swab specimens were collected from pregnant women at 35-37 weeks of gestation. The chromogenic broth enrichment culture, Xpert GBS LB, immunochromatography and general culture were used for detection respectively. The color-increasing broth enrichment culture method was used as the "gold standard", to evaluate the diagnosis efficiency of the other three methods and the consistency with their results. Results In 1063 specimens from reproductive tract or rectum of perinatal women, 251 cases(23.61%) were positive detected by Xpert GBS LB, 261 cases(24.55%) were positive by immunochromatography and 193 cases(18.16%) by general culture method. Compared with the "gold standard", Xpert GBS LB test and general culture method had a very high consistency, but immunochromatography had a moderate consistency. General culture method had the highest specificity, Xpert GBS LB had the highest sensitivity, while immunochromatography has poor sensitivity and specificity. Conclusion All three laboratory methods are suitable for clinical GBS screening, in which Xpert GBS LB and general culture method are highly consistent with the "gold standard". The Xpert GBS LB method is not only highly consistent but also highly sensitive, which is suitable for rapid screening of GBS.