围产期B族链球菌感染及其对妊娠结局的影响

Influence of perinatal group B Streptococcus infection on pregnancy outcomes

目的探讨围产期B族链球菌(GBS)感染及其对妊娠结局的影响。方法选择2017年3月-2019年12月于新乡市中心医院产科进行产前检查的674例孕妇作为研究对象,检测孕妇GBS带菌情况及菌株耐药性、荚膜血清学分型、表面蛋白基因、菌毛蛋白基因分布,收集孕妇妊娠结局。结果 674例孕妇共检出GBS阳性98例,阳性率为14.54%。药敏试验显示,98株GBS菌株对红霉素、克林霉素、四环素耐药率>50%,未检出青霉素、头孢噻肟、万古霉素耐药株;98株GBS菌株共检出5种基因型,其中Ia型14株(14.29%)、Ib型27株(27.55%)、Ⅱ型4株(4.08%)、Ⅲ型45株(45.92%)、IV型8株(8.16%);93株菌株均检出表面蛋白基因,以rib、esp、bca基因为主,alp2/3检出率最低;所有菌株均至少检出一种菌毛蛋白基因,以P1-2a+P1-1、P1-2b为主;GBS阳性孕妇胎膜早破、早产发生率及总不良妊娠结局发生率高于GBS阴性孕妇(P<0.05);Logsitic多因素分析显示,产妇年龄、产次、有异常孕产史、妊娠合并症、GBS阳性是不良妊娠结局的独立影响因素(P<0.05)。结论孕妇GBS带菌率较高,与不良妊娠结局密切相关,监测其耐药性、毒力因子分布对于抗菌药物选择、疫苗研发均可提供理论依据及数据支持。

OBJECTIVE To explore the influence of perinatal group B Streptococcus(GBS) infection on pregnancy outcomes. METHODS A total of 674 pregnant women who received prenatal check-ups in substetrics department of Xinxiang Central Hospital from Mar 2017 to Dec 2019 were recruited as the study objects. The positive rate of GBS, drug resistance, capsular serotypes, surface protein genes and pilin genes were detected, and the pregnancy outcomes were observed. RESULTS Among the 674 pregnant women, 98 were tested positive for GBS, with the positive rate 14.54%. The drug resistance rates of 98 strains of GBS to erythromycin, clindamycin and tetracycline were more than 50%, and no strains that were resistant to penicillin, cefotaxime or vancomycin were found. Totally 5 genotypes were detected from the 98 strains of GBS, there were 14(14.29%) strains with type Ia, 27(27.55%) strains with type Ib, 4(4.08%) strains with type Ⅱ, 45(45.92%) strains with type Ⅲ and 8(8.16%) strains with type IV. All of the 93 strains were detected with surface protein gens, among which rib, esp and bca gene were dominant, and the detection rate of alp2/3 was the lowest. All of the strains were detected with at least 1 type of pilin gene, and P1-2 a+P1-1 and P1-2 b were dominant. The incidence of premature rupture of membranes and premature delivery and total incidence of adverse pregnancy outcomes of the GBS-positive pregnant women were significantly higher than those of the GBS-negative pregnant women(P<0.05). Multivariate logistic analysis showed that age, parity, history of abnormal pregnancy, pregnancy comorbidities and positive test of GBS were the independent influencing factors for the adverse pregnancy outcomes(P<0.05). CONCLUSION The positive rate of GBS is high among pregnant women, which is closely associated with the adverse pregnancy outcomes. The surveillance of drug resistance and virulence genes may provide theoretical basis and data support for use of antibiotics and development of vaccine.