Clinical impact of rapid polymerase chain reaction (PCR) test for group B Streptococcus (GBS) in term women with ruptured membranes

Abstract

Background: Early-onset group B Streptococcus (EOGBS/GBS) infection remains a significant cause of neonatal morbidity and mortality. Aims: Aiming to improve antimicrobial stewardship and reduce unnecessary maternal and infant exposure to intrapartum antibiotic prophylaxis (IAP), this study assessed the clinical use of a commercially available GBS polymerase chain reaction (PCR) assay for term women with pre-labour rupture of membranes. Methods: This was a retrospective study in a tertiary level maternity unit of term women with pre-labour rupture of membranes (ROM), without any clinical suspicion of infection performed between November and December 2017. GBS PCR tests were cross-referenced with patient clinical data. PCR test results, the impact of testing on antibiotic administration, pyrexia in labour, induction, interventional delivery rates and neonatal outcomes were analysed. Results: Of 200 patients included in the study, 29 were positive (14.5%) and 166 were negative (83%), with five invalid results (2.5%). One hundred and twenty three women had > 18-h ruptured membranes and 86 women (70%) who would have been eligible for IAP based on risk factors avoided antibiotic therapy following a negative PCR test. There were no significant differences in induction or interventional delivery rates between GBS-positive and GBS-negative women following PCR testing. During the study period, there were no cases of EOGBS. Conclusions: In a centre adhering to a risk-factor-based GBS policy, the introduction of limited rapid GBS screening for term women with pre-labour rupture of membranes resulted in a clinically significant reduction in prophylactic antibiotic use.