From the Guidelines
Women with GBS bacteriuria in any concentration during their current pregnancy should receive intrapartum antimicrobial prophylaxis. The treatment for Group B Streptococcus (GBS) bacteriuria is primarily focused on preventing the transmission of GBS to the newborn during delivery, rather than treating the bacteriuria itself 1. According to the CDC guidelines, women with GBS bacteriuria should receive intrapartum antimicrobial prophylaxis, which typically consists of penicillin or ampicillin administered intravenously during labor 1. For women allergic to penicillin, alternative regimens such as cefazolin, clindamycin, or vancomycin may be used, depending on the severity of the allergy and the susceptibility of the GBS isolate 1.
Key Considerations
- The primary goal of treatment is to prevent early-onset GBS disease in the newborn, rather than to treat the bacteriuria itself.
- Intravenous antibiotics during labor are still required for GBS-positive pregnant women, regardless of prior treatment.
- Women with GBS bacteriuria should receive intrapartum antimicrobial prophylaxis, regardless of the concentration of GBS in the urine.
- The choice of antibiotic regimen depends on the presence and severity of penicillin allergy, as well as the susceptibility of the GBS isolate.
Treatment Regimens
- Penicillin or ampicillin are the preferred agents for intrapartum antibiotic prophylaxis in women without penicillin allergy 1.
- Cefazolin is recommended for women allergic to penicillin who are at low risk of anaphylaxis 1.
- Clindamycin or vancomycin may be used in women allergic to penicillin who are at high risk of anaphylaxis, depending on the susceptibility of the GBS isolate 1.
From the Research
Treatment for Group B Streptococcus (GBS) Bacteriuria
- The treatment for Group B Streptococcus (GBS) bacteriuria typically involves intrapartum antibiotic prophylaxis (IAP) to prevent the transmission of GBS from mother to neonate during delivery 2, 3, 4, 5.
- Penicillin G is the primary antibiotic used for IAP, with clindamycin or erythromycin as secondary options in cases of penicillin allergy 2, 4.
- However, there is growing concern over the increasing resistance to clindamycin and erythromycin, with studies reporting resistance rates of up to 32.9% and 26.6%, respectively 2.
- In cases where patients are allergic to penicillin and second-line antibiotics are ineffective, vancomycin may be administered as a last resort 3.
- The American College of Obstetricians and Gynecologists (ACOG) recommends screening for GBS between 36 and 37 weeks of gestation, and administering IAP to patients who test positive 5.
- Patients with GBS in their urine should be treated with antibiotic prophylaxis at term, regardless of the colony count of the culture 5.
Antibiotic Resistance and Treatment Strategies
- GBS is still recognized as being universally susceptible to beta-lactam antibiotics, including penicillin, although there have been reports of reduced susceptibility in some countries 3.
- Resistance to second-line antibiotics, such as erythromycin and clindamycin, remains high amongst GBS, with several countries noting increased resistance rates in recent years 2, 3.
- The development of a conjugate vaccine has been shown to be effective in preventing GBS in neonates, and may be a useful adjunct to IAP and antenatal screening 6.
- Penicillin remains an important core antibiotic for treating early-onset GBS disease, and IAP according to guidelines may be effective in reducing the incidence of the disease 6.