From the Guidelines
For a urinary tract infection (UTI) caused by Group B Streptococcus (GBS), the recommended first-line antibiotic treatment is penicillin G or ampicillin, as stated in the guidelines from the CDC 1.
Recommended Treatment
- Penicillin G is typically dosed at 5 million units IV initial dose, then 2.5–3.0 million units every 4 hours until delivery, as recommended for intrapartum antibiotic prophylaxis 1.
- Ampicillin is an acceptable alternative, dosed at 2 g IV initial dose, then 1 g IV every 4 hours until delivery, as recommended for intrapartum antibiotic prophylaxis 1.
Considerations for Penicillin Allergies
- For patients with penicillin allergies, alternatives include cefazolin, clindamycin, or vancomycin, depending on the severity of the allergy and the susceptibility of the GBS isolate 1.
- Cefazolin is recommended for patients with a history of anaphylaxis, angioedema, or urticaria, while clindamycin and vancomycin are reserved for patients with severe penicillin allergies 1.
Importance of Treatment
- Treatment of GBS UTIs is crucial to prevent complications, including pyelonephritis and potential transmission to the newborn during delivery, especially in pregnant women 1.
- Completing the full course of antibiotics and maintaining adequate hydration are essential for effective treatment and prevention of complications.
Key Points
- GBS remains highly susceptible to penicillins, making them the treatment of choice 1.
- Follow-up urine cultures may be necessary to confirm the infection has cleared completely.
- The CDC guidelines provide recommendations for the management of GBS UTIs, including treatment and prevention of complications 1.
From the Research
UTI and Group B Strep Treatment
- For patients with UTI growing Group B strep, the recommended antibiotics are:
- Nitrofurantoin, as suggested by the study 2
- Ampicillin, with specific dosing recommendations for bacteremia and meningitis, as outlined in the study 3
- Vancomycin, as an alternative for patients allergic to penicillin, as mentioned in the study 2 and 4
- Cefazolin, also used for intrapartum neonatal sepsis prophylaxis in patients with penicillin allergy, as reported in the study 4
- It is essential to determine the antibiotic sensitivity pattern of the Group B strep isolate to guide the selection of antibiotics, as emphasized in the study 2 and 4
- The choice of antibiotic should be based on the patient's allergy status and the results of antibiotic susceptibility testing, as highlighted in the study 4
Antibiotic Resistance and Sensitivity
- The study 2 found that all Group B strep isolates were sensitive to vancomycin, ofloxacin, ampicillin, ciprofloxacin, nitrofurantoin, and penicillin
- However, some isolates exhibited intermediate or decreased sensitivity to these antibiotics, and 35% of the isolates were resistant to 6 of the 12 antibiotics tested, as reported in the study 2
- The study 4 found that cefazolin and vancomycin were the most frequently prescribed antibiotics for intrapartum neonatal sepsis prophylaxis in patients with penicillin allergy
Dosing Recommendations
- The study 3 discussed the dosing recommendations for ampicillin in neonates with Group B strep disease, including bacteremia and meningitis
- The dosing recommendations were based on the pharmacokinetics and pharmacodynamics of ampicillin in neonates, as reported in the study 3
- However, the study 3 also noted that the supporting evidence for the dosing recommendations was limited, particularly for meningitis.