Does Group B strep (GBS) bacteriuria require treatment?

Management of Group B Streptococcus in Urine During Pregnancy

Yes, Group B Streptococcus (GBS) detected in urine during pregnancy requires treatment, regardless of colony count, as it is a recognized risk factor for early-onset GBS disease in newborns. 1

Treatment Approach for GBS Bacteriuria

Immediate Management

• Women with GBS isolated from urine at any time during pregnancy require:
  1. Treatment of the current urinary tract infection if symptomatic 1
  2. Intrapartum antibiotic prophylaxis (IAP) during labor to prevent early-onset GBS disease 2, 1

Treatment Specifics

• For symptomatic GBS UTI: Treat according to current standards of care for UTI during pregnancy 2
• Standard duration of therapy for GBS urinary tract infections is 7-14 days 1
• No need to re-screen these women with vaginal-rectal cultures at 36-37 weeks as they are already considered GBS colonized 3

Intrapartum Antibiotic Prophylaxis

All women with GBS bacteriuria during pregnancy should receive IAP during labor with one of the following regimens 1:

• First-line therapy:

  • Penicillin G: 5 million units IV initial dose, then 2.5-3.0 million units IV every 4 hours until delivery
  • Ampicillin: 2 g IV initial dose, then 1 g IV every 4 hours until delivery

• For penicillin allergy:

  • Cefazolin: 2 g IV initial dose, then 1 g IV every 8 hours (if no anaphylaxis history)
  • Clindamycin or vancomycin (based on sensitivity testing) for severe penicillin allergy

Important Clinical Considerations

Colony Count Significance

• The CDC and ACOG recommend treatment regardless of colony count 1
• This differs from traditional UTI management where ≥100,000 CFU/mL is typically considered significant 3
• The presence of GBS in urine indicates heavy maternal colonization, which increases the risk of neonatal disease 1, 4

Risk Factors and Complications

• Untreated GBS bacteriuria is associated with higher rates of:
  • Preterm labor
  • Premature rupture of membranes
  • Neonatal infectious complications 1, 4

Special Situations

• Patients who are GBS-positive with preterm premature rupture of membranes after 34 weeks are not candidates for expectant management due to higher rates of neonatal infectious complications 1, 4
• Cesarean delivery performed before onset of labor with intact membranes does not require IAP, regardless of GBS status 2

Common Pitfalls to Avoid

1. Failing to treat asymptomatic GBS bacteriuria - Unlike other asymptomatic bacteriuria, GBS requires treatment due to implications for neonatal disease
2. Re-screening women with prior GBS bacteriuria - Not necessary as they are already candidates for IAP 3
3. Withholding IAP for women with treated GBS bacteriuria - Even if treated earlier in pregnancy, IAP is still required during labor 1
4. Overlooking communication - Ensure information about GBS bacteriuria is communicated to all providers involved in the patient's care, particularly those managing labor and delivery 1

By following these evidence-based recommendations, clinicians can significantly reduce the risk of early-onset GBS disease in newborns, which remains a significant cause of neonatal sepsis, morbidity, and mortality 4, 5.