Laboratório de Biologia Molecular em Doenças Auto-imunes e Infecciosas, Centro de Pesquisas, Hospital de Clínicas de Porto Alegre , Porto Alegre, RS , Brasil.
Braz J Microbiol. 2012 Jan;43(1):253-60. doi: 10.1590/S1517-838220120001000029. Epub 2012 Jun 1.
Group B Streptococcus (GBS) is the most common cause of life-threatening infection in neonates. Guidelines from CDC recommend universal screening of pregnant women for rectovaginal GBS colonization. The objective of this study was to compare the performance of a combined enrichment/PCR based method targeting the atr gene in relation to culture using enrichment with selective broth medium (standard method) to identify the presence of GBS in pregnant women. Rectovaginal GBS samples from women at ≥36 weeks of pregnancy were obtained with a swab and analyzed by the two methods. A total of 89 samples were evaluated. The prevalence of positive results for GBS detection was considerable higher when assessed by the combined enrichment/PCR method than with the standard method (35.9% versus 22.5%, respectively). The results demonstrated that the use of selective enrichment broth followed by PCR targeting the atr gene is a highly sensitive, specific and accurate test for GBS screening in pregnant women, allowing the detection of the bacteria even in lightly colonized patients. This PCR methodology may provide a useful diagnostic tool for GBS detection and contributes for a more accurate and effective intrapartum antibiotic and lower newborn mortality and morbidity.
B 组链球菌（GBS）是导致新生儿危及生命感染的最常见原因。疾病预防控制中心的指南建议对孕妇进行普遍的直肠阴道 GBS 定植筛查。本研究的目的是比较针对 atr 基因的联合富集/PCR 方法与使用选择性肉汤培养基进行富集（标准方法）在识别孕妇 GBS 存在方面的性能。用拭子采集≥36 周妊娠妇女的直肠阴道 GBS 样本，并通过两种方法进行分析。共评估了 89 个样本。与标准方法相比，联合富集/PCR 方法检测 GBS 的阳性结果率明显更高（分别为 35.9%和 22.5%）。结果表明，使用选择性富集肉汤，然后针对 atr 基因进行 PCR 是一种高度敏感、特异和准确的孕妇 GBS 筛查试验，即使在定植较轻的患者中也能检测到细菌。这种 PCR 方法学可能为 GBS 检测提供有用的诊断工具，并有助于更准确和有效地进行产时抗生素治疗，降低新生儿死亡率和发病率。
