From the Guidelines
For treating Group B Streptococcus (GBS) urinary tract infections in penicillin-allergic patients, vancomycin is the recommended first-line alternative, administered at 1 g IV every 12 hours until delivery, as it is the preferred agent for penicillin-allergic women at high risk for anaphylaxis 1. When considering treatment options, it's crucial to assess the severity of the penicillin allergy, as this guides the choice of antibiotic.
- For patients with a history of anaphylaxis, angioedema, respiratory distress, or urticaria following administration of penicillin or a cephalosporin, vancomycin is the preferred choice due to its effectiveness and safety profile 1.
- Clindamycin can be considered if the GBS isolate is susceptible to clindamycin and erythromycin, or if testing for inducible clindamycin resistance has been performed and is negative 1. Key considerations in treating GBS urinary tract infections include:
- The need for effective intraamniotic concentrations of the chosen antibiotic
- The potential for cross-reactivity with other antibiotics, such as cephalosporins
- The importance of local susceptibility data in guiding treatment decisions
- The potential for resistance to certain antibiotics, such as fluoroquinolones In the context of real-life clinical medicine, vancomycin remains the most appropriate choice for penicillin-allergic patients with GBS urinary tract infections, due to its efficacy and safety profile 1.
From the Research
Treatment Options for GBS Urinary Tract Infection in PCN Allergic Patients
- In patients allergic to penicillin, alternative antibiotics such as erythromycin, clindamycin, or vancomycin may be considered for the treatment of Group B Streptococcus (GBS) urinary tract infections (UTIs) 2.
- However, resistance to erythromycin and clindamycin is common among GBS isolates, with reported resistance rates of 39.5% and 26.4%, respectively 3.
- Vancomycin is often used as a last resort antibiotic, but there have been reports of vancomycin resistance in GBS 2.
- In cases where patients are allergic to penicillin and second-line antibiotics are ineffective, alternative treatment options may need to be considered, such as azithromycin or tetracycline, although resistance to these antibiotics has also been reported 4.
Antibiotic Resistance Patterns
- GBS isolates have shown high levels of multidrug resistance, with 33.6% of isolates resistant to four or more antibiotics 4.
- The most common resistance patterns include resistance to azithromycin, clindamycin, erythromycin, and tetracycline 4.
- However, no resistance was detected to other antibiotics, such as beta-lactams, which are often considered the first-line treatment for GBS infections 4.
Clinical Considerations
- In patients with a history of UTI, GBS UTI is more likely to occur, and increased age is also a significant risk factor for acute infection 3.
- The most common serotypes causing GBS UTI are serotypes V, Ia, and III, although other serotypes may also be involved 3, 5.
- Antibiotic susceptibility testing is essential to guide treatment decisions, especially in patients with a history of antibiotic use or resistance 6.