Treatment of Group B Streptococcus Urinary Tract Infection

Dosing Recommendations

For uncomplicated Group B Streptococcal urinary tract infections, the American Academy of Pediatrics recommends ampicillin at a dose of 500 mg orally every 8 hours for 3-7 days 1, 2
For complicated UTIs or severe infections, the recommended dose is 18-30 g/day IV in divided doses 3, 4
Alternative oral option: Amoxicillin 500 mg every 8 hours 3, 1
For children, ampicillin 150-400 mg/kg/day IV in 4 divided doses (maximum 12,000 mg/day) is recommended 1
For neonates and young infants, dosing depends on gestational and postnatal age, with a recommended dose of 50 mg/kg/dose IV every 12 hours for gestational age >34 weeks, postnatal age ≤7 days 1

For uncomplicated UTI, the recommended duration of therapy is 3-7 days 1, 2
For complicated UTI, the recommended duration of therapy is 5-7 days 3, 1
For severe infections or bacteremia, the recommended duration of therapy is 10-14 days 3, 4

For patients with penicillin allergies, alternative agents should be selected based on susceptibility testing 4

Urine culture should be obtained before initiating therapy to confirm the diagnosis and guide treatment 2
Significant bacteriuria is defined as ≥50,000 CFUs/mL of a single urinary pathogen 2
For complicated or recurrent infections, evaluation for structural abnormalities of the urinary tract may be indicated 2
Distinguishing between colonization and true infection is important to avoid unnecessary treatment 5

For patients with penicillin allergies or treatment failures, consider Nitrofurantoin 100 mg orally four times daily for uncomplicated UTI 3, 1
For patients with penicillin allergies or treatment failures, consider Fosfomycin 3 g orally as a single dose for uncomplicated UTI 3, 1
For complicated infections, consult infectious disease specialists for alternative regimens 4