From the Guidelines
For a urinary tract infection (UTI) caused by Group B Streptococcus (GBS) with 10,000-49,000 CFU/mL in urine, the recommended treatment is according to current standards of care for urinary tract infections, which typically involves a 5-7 day course of antibiotics, with first-line options including amoxicillin or penicillin V for non-pregnant women, and amoxicillin generally preferred during pregnancy 1. The choice of antibiotic should be guided by the susceptibility of GBS to beta-lactam antibiotics, such as penicillins, which inhibit cell wall synthesis in the bacteria.
- For patients without penicillin allergies, amoxicillin 500 mg three times daily or penicillin V 500 mg four times daily are suitable options.
- For patients with penicillin allergies but no history of anaphylaxis, cephalexin 500 mg four times daily can be considered.
- For pregnant women, amoxicillin is generally the preferred choice due to its safety profile and effectiveness against GBS. It is crucial to complete the full course of antibiotics, even if symptoms resolve earlier, to ensure the infection is fully cleared and to reduce the risk of complications, such as the bacteria ascending to the kidneys or causing systemic infection. Increased fluid intake is also recommended to help flush bacteria from the urinary tract. Given that GBS bacteriuria in any concentration is a marker for heavy genital tract colonization, women with GBS urinary tract infections during pregnancy should receive appropriate treatment at the time of diagnosis as well as intrapartum GBS prophylaxis, as outlined in the guidelines for the prevention of perinatal group B streptococcal disease 1.
From the FDA Drug Label
To minimize the potential for gastrointestinal intolerance, amoxicillin should be taken at the start of a meal. Treatment should be continued for a minimum of 48 to 72 hours beyond the time that the patient becomes asymptomatic, or evidence of bacterial eradication has been obtained It is recommended that there be at least 10 days’ treatment for any infection caused by Streptococcus pyogenes to prevent the occurrence of acute rheumatic fever. Genitourinary Tract Mild/ Moderate 500 mg every 12 hours or 250 mg every 8 hours
The recommended treatment for a urinary tract infection caused by Group B Streptococcus is amoxicillin. The dosage for Genitourinary Tract infections is 500 mg every 12 hours or 250 mg every 8 hours for mild to moderate infections. Treatment should be continued for at least 10 days and for a minimum of 48 to 72 hours beyond the time that the patient becomes asymptomatic, or evidence of bacterial eradication has been obtained 2.
From the Research
Treatment Options for Group B Streptococcus Urinary Tract Infection
- The recommended treatment for a urinary tract infection caused by Group B Streptococcus is typically with beta-lactam antibiotics, such as penicillin or ampicillin, as these bacteria are generally susceptible to these antibiotics 3, 4, 5.
- According to the provided test results, beta-hemolytic streptococci, including Group B Streptococcus, are predictably susceptible to penicillin and other beta-lactams.
- However, it is essential to note that susceptibility testing is not routinely performed, and if desired, it should be requested from the laboratory within 3 days.
- Alternative treatment options, such as nitrofurantoin, may be considered for patients with Group B Streptococcus bacteriuria, as suggested by a study published in 2004 4.
- Amoxicillin-clavulanic acid combinations have also been shown to be effective in treating urinary tract infections caused by beta-lactamase-producing bacteria, including those resistant to penicillin 6, 7.
Antibiotic Susceptibility Patterns
- Studies have reported that Group B Streptococcus isolates are generally susceptible to penicillin, ampicillin, and vancomycin 3, 4, 5.
- However, some isolates may exhibit reduced susceptibility or resistance to other antibiotics, such as azithromycin, ceftriaxone, and clindamycin 4, 5.
- The antibiotic susceptibility pattern of the specific isolate should guide the selection of an appropriate antibiotic for treatment, especially in patients allergic to penicillin 4, 5.