The prevalence of Group B Streptococcus rectovaginal colonization and antimicrobial susceptibility pattern in Turkish...

Colonization with Group B Streptococcus (GBS) during pregnancy can lead to invasive GBS disease (iGBS) in neonates, including meningitis, pneumonia or sepsis, which carries a high mortality risk. American College of Obstetricians and Gynecologists (ACOG) recommends universal GBS screening for all pregnant individuals between 36 0/7 and 37 6/7 weeks of gestation. However, due to the insufficient population-based studies on universal screening and GBS colonization rates in late periods of pregnancy in Türkiye, we aimed to evaluate the prevalence of GBS and its antibiotic resistance to enhance awareness regarding GBS screening and prophylaxis during pregnancy and promote the use of appropriate antibiotics.

This prospective, single-center study was conducted between May 2017 and December 2017 on 518 pregnant women (363 Turkish and 155 Syrian). Vaginal and rectal samples were collected and cultured in Todd-Hewitt broth. Standard microbiological protocols were used to assess GBS colonization and antibiotic susceptibility.

In the study, we found that 10.6% (n = 55) of pregnant women were colonized with GBS asymptomatically. Group B Streptococcus colonization rates did not differ significantly between Turkish patients (11%, n = 40) and Syrian patients (9.7%, n = 15) (p = 0.756, p > 0.05). All patients colonized with GBS were penicillin-sensitive. However, resistance to at least one non-penicillin antibiotic was observed in 42.5% (n = 17) of Turkish patients and 60% (n = 9) of Syrian patients. Although not statistically significant (p > 0.05), Syrian patients exhibited relatively higher rates of antibiotic resistance, especially to erythrosine and clindamycin.

In our country, implementing universal screening for asymptomatic GBS in pregnant women, as recommended by the Centers for Disease Control and Prevention (CDC), would be more beneficial than a risk-based screening approach. Given the increased resistance patterns observed in antibiogram results, GBS prophylaxis at delivery, especially in patients with penicillin allergies, should be planned based on antibiotic susceptibility testing.