What is the treatment for Group B strep (Streptococcus agalactiae) in urine?

Treatment of Group B Streptococcus in Urine

Women with Group B Streptococcus (GBS) bacteriuria during pregnancy should be treated according to current standards of care for urinary tract infection regardless of colony count, followed by intrapartum antibiotic prophylaxis during labor to prevent early-onset GBS disease. 1

Diagnosis and Significance

• GBS in urine during pregnancy indicates heavy genital tract colonization and increases risk for early-onset neonatal GBS disease 1
• Even low concentrations of GBS in urine can indicate heavy colonization, and treatment should not be withheld based on colony count alone 1
• Laboratories should report GBS in urine culture specimens when present at concentrations of ≥10^4 colony-forming units/ml in pure culture or mixed with a second microorganism 1

Treatment Protocol

Non-pregnant Adults with GBS UTI

First-line treatment options:

• Penicillin G
• Ampicillin
• Nitrofurantoin (for uncomplicated lower UTIs) 1

For Penicillin-Allergic Patients

Alternative options:

• Cefazolin (if non-anaphylactic allergy)
• Clindamycin
• Vancomycin (for severe penicillin allergy) 1

Treatment Duration

• For uncomplicated UTI: Standard UTI treatment course
• For complicated UTIs or pyelonephritis: 10-14 days of beta-lactam antibiotics 1

Special Considerations for Pregnant Women

1. Initial Treatment:

   • Treat GBS bacteriuria during pregnancy regardless of colony count 1
   • Use appropriate antibiotics according to susceptibility testing

2. Follow-up:

   • Perform follow-up urine culture after treatment completion 1
   • No need for vaginal and rectal screening at 35-37 weeks if GBS bacteriuria was detected earlier in pregnancy 1

3. Intrapartum Management:

   • Intrapartum antibiotic prophylaxis is REQUIRED during labor, regardless of whether treatment was provided earlier in pregnancy 1
   • This is because antibiotics during pregnancy do not eliminate GBS from genitourinary and gastrointestinal tracts, and recolonization after treatment is common 1

Important Clinical Caveats

• Women with GBS bacteriuria at any time during pregnancy are automatically candidates for intrapartum antibiotic prophylaxis and do not need third-trimester screening for GBS colonization 2
• Treatment of GBS bacteriuria during pregnancy may also reduce rates of preterm labor 3
• Do not re-screen women with documented GBS bacteriuria by genital tract culture or urinary culture in the third trimester, as they are presumed to be GBS colonized 4
• Asymptomatic women with urinary GBS colony counts < 100,000 CFU/mL should still receive treatment during pregnancy, contrary to previous recommendations that suggested only treating high colony counts 1

This approach to managing GBS bacteriuria during pregnancy helps reduce the risk of maternal complications and early-onset neonatal GBS disease, which remains a significant cause of neonatal morbidity and mortality 5.