Department of Obstetrics and Gynecology, Copenhagen University Hospital, Hvidovre, Denmark.
Department of Obstetrics and Gynecology, Copenhagen University Hospital, Hvidovre, Denmark.
Eur J Obstet Gynecol Reprod Biol. 2019 Sep;240:178-181. doi: 10.1016/j.ejogrb.2019.06.037. Epub 2019 Jul 2.
To estimate the prevalence of group B streptococcus at onset of labor and to compare the accuracy of intrapartum antibiotic prophylaxis based on a risk factor strategy versus an intrapartum screening.
In this cross-sectional study, 700 women referred for intended vaginal delivery were tested for group B streptococcus at onset of labor by gold standard culture in vaginal and rectal swabs. The results were blinded, and intrapartum antibiotic prophylaxis was given to women with risk factors for group B streptococcus infection: previous neonatal group B streptococcus infection, group B streptococcus in urine and/or vagina in current pregnancy, gestational age <36 + 0 weeks, temperature ≥38.0 °C or rupture of membranes ≥18 h.
Of 642 women, who delivered within three days of specimen collection, 170 (26.5%) received benzylpenicillin as intrapartum antibiotic prophylaxis based on risk factors. The prevalence of group B streptococcus at onset of labor was 17.8% (114/642), with 62 women positive for group B streptococcus in both the vagina and rectum, 12 in the vagina only and 40 in rectum only. Intrapartum antibiotic prophylaxis was administered correctly in 31.6% (36/114) of GBS positive women at time of delivery and 78.8% (134/170) of women who received antibiotics were actually GBS negative. The positive predictive value of intrapartum antibiotic prophylaxis based on risk factors was 21.2%. The sensitivity was 31.6% and the specificity was 74.6%.
The accuracy of predicting maternal group B streptococcus infection from risk factors is low. Intrapartum group B streptococcus diagnostics is more precise and will not increase the overall use of intrapartum antibiotic prophylaxis.
估计临产时 B 群链球菌的流行率，并比较基于危险因素策略与产时筛查的产时抗生素预防的准确性。
在这项横断面研究中，700 名计划阴道分娩的妇女在临产时通过阴道和直肠拭子的金标准培养检测 B 群链球菌。结果是盲法的，对有 B 群链球菌感染危险因素的妇女给予产时抗生素预防：新生儿 B 群链球菌感染史、当前妊娠 B 群链球菌尿和/或阴道感染、妊娠龄<36+0 周、体温≥38.0°C 或胎膜破裂≥18 小时。
在标本采集后三天内分娩的 642 名妇女中，170 名（26.5%）根据危险因素接受了苄星青霉素作为产时抗生素预防。临产时 B 群链球菌的流行率为 17.8%（114/642），其中 62 名妇女阴道和直肠均为 B 群链球菌阳性，12 名仅阴道阳性，40 名仅直肠阳性。在分娩时，114 名 B 群链球菌阳性妇女中有 31.6%（36/114）正确使用了产时抗生素预防，而实际接受抗生素的 170 名妇女中有 78.8%（134/170）为 B 群链球菌阴性。基于危险因素的产时抗生素预防的阳性预测值为 21.2%。敏感性为 31.6%，特异性为 74.6%。
从危险因素预测产妇 B 群链球菌感染的准确性较低。产时 B 群链球菌诊断更为准确，不会增加产时抗生素预防的总体使用。
