Intrapartum group B streptococcus antibiotic prophylaxis in beta-lactams allergic women and risk of neonatal infection.

OBJECTIVE

In women with Group B Streptococcus (GBS) vaginal colonization who report a beta-lactams allergy, the prevention of neonatal GBS early-onset disease (EOD) mainly relies on maternal antibiotic prophylaxis with lincosamides during labor. With approximately 30% of GBS being resistant to macrolides or lincosamides, this antibiotic prophylaxis may be inappropriate, leading to a risk of EOD. We aim to measure the proportion of inappropriate antibiotic prophylaxis despite the existence of an antibiotic susceptibility testing, and its possible impact on the newborn.

METHODS

Single-center retrospective study between 2012 and 2021 among women with beta-lactam allergy and GBS vaginal colonization in the 3rd trimester, for whom an antibiotic susceptibility testing had been performed.

RESULTS

Among 138 beta-lactam allergic pregnant women with GBS vaginal colonization, 30 carried a strain resistant to clindamycin (21.7%). Eight gave birth before a first antibiotic injection could be administered (labor < 2 h). Of the 130 other women eligible for antibiotic prophylaxis, 17 did not receive appropriate antibiotic treatment (13.1%). Finally, among eight newborns presented with EOD, two had received inappropriate antibiotic prophylaxis. There was no clear evidence of an increased risk of EOD in women who received inappropriate antibiotic prophylaxis (OR 2.9 [0.5; 16.2], P = 0.23), although receiving ineffective treatment intuitively seems more likely to increase the risk.

CONCLUSION

Pregnant women colonized with group B streptococcus who report an allergy to beta-lactams may receive inappropriate or ineffective antibiotic prophylaxis, which could potentially lead to a higher risk of EOD.