Gavino Michael, Wang Eileen
Department of Obstetrics and Gynecology, University of Chicago, Chicago, IL, USA.
Am J Obstet Gynecol. 2007 Oct;197(4):388.e1-4. doi: 10.1016/j.ajog.2007.06.016.
The objective of the study was to evaluate a rapid real-time polymerase chain reaction (PCR)-based assay for intrapartum detection of group B streptococcus (GBS).
This prospective, observational study enrolled outpatients after GBS screening at 35-37 weeks' gestation. At admission for delivery, paired rectovaginal swabs were obtained for the GBS GeneXpert (Cepheid, Sunnyvale, CA) assay and standard culture. Using the intrapartum culture as the gold standard, sensitivities, specificities, and predictive values of the rapid assay and the antenatal screen were determined. Statistical significance was determined by Fisher's exact test.
Fifty-five subjects had both rapid test and intrapartum culture results. The intrapartum GBS colonization rate was 43.6%. The sensitivity and specificity of the PCR test were 95.8% (95% confidence interval [CI], 76.9-99.8%), and 64.5% (95% CI, 45.4-80.2%), respectively, whereas the antenatal culture sensitivity was 83.3% and specificity was 80.6%.
The GeneXpert rapid GBS point-of-care assay was highly sensitive for GBS detection in our sample population. Corroboration of these data is needed on a large population basis.
本研究的目的是评估一种基于实时聚合酶链反应（PCR）的快速检测方法，用于产时B族链球菌（GBS）的检测。
这项前瞻性观察性研究纳入了妊娠35-37周时进行GBS筛查后的门诊患者。在入院分娩时，采集配对的直肠阴道拭子用于GBS GeneXpert（Cepheid公司，加利福尼亚州桑尼维尔）检测和标准培养。以产时培养作为金标准，确定快速检测方法和产前筛查的敏感性、特异性及预测值。采用Fisher精确检验确定统计学意义。
55名受试者同时有快速检测结果和产时培养结果。产时GBS定植率为43.6%。PCR检测的敏感性和特异性分别为95.8%（95%置信区间[CI]，76.9-99.8%）和64.5%（95%CI，45.4-80.2%），而产前培养的敏感性为83.3%，特异性为80.6%。
在我们的样本人群中，GeneXpert快速GBS即时检测方法对GBS检测具有高度敏感性。需要在大量人群中对这些数据进行验证。
