Is Clindamycin (clindamycin) effective for Group B Streptococcus (GBS) positive patients?

From the Guidelines

Clindamycin is an effective alternative antibiotic for women who are allergic to penicillin and have tested positive for Group B Streptococcus (GBS) during pregnancy, but only if the GBS isolate is susceptible to clindamycin, as determined by antimicrobial susceptibility testing, including testing for inducible clindamycin resistance 1. The recommended dosage for intrapartum prophylaxis is 900 mg intravenously every 8 hours until delivery. Some key points to consider when using clindamycin for GBS prophylaxis include:

• Treatment should begin when labor starts or when membranes rupture and continue until the baby is delivered.
• For women with a documented penicillin allergy who are GBS positive, clindamycin can be used if the GBS isolate has been tested and confirmed to be susceptible to clindamycin.
• If susceptibility is unknown or the isolate is resistant to clindamycin, vancomycin (1 g IV every 12 hours until delivery) should be used instead, as recommended by the CDC guidelines 1.
• The purpose of this antibiotic prophylaxis is to prevent vertical transmission of GBS from mother to baby during delivery, which can cause serious neonatal infections including sepsis, pneumonia, and meningitis.
• Clindamycin works by inhibiting bacterial protein synthesis, effectively reducing the bacterial load in the birth canal during delivery and decreasing the risk of neonatal GBS disease. It's also important to note that the American Academy of Pediatrics (AAP) has updated guidelines for the management of at-risk infants, which include recommendations for the use of clindamycin and vancomycin for GBS prophylaxis 1. In terms of antibiotic resistance, GBS isolates have shown increasing resistance to erythromycin and clindamycin, with some studies reporting resistance rates of up to 32% for erythromycin and 20% for clindamycin 1. Therefore, it's crucial to perform antimicrobial susceptibility testing, including testing for inducible clindamycin resistance, to ensure the effective use of clindamycin for GBS prophylaxis 1.

From the Research

Effectiveness of Clindamycin for Group B Streptococcus (GBS) Positive Patients

• The effectiveness of clindamycin for preventing early-onset group B streptococcal disease is lower compared to penicillin or ampicillin, with an effectiveness of 22% (95% CI -53% to +60%) 2.
• Clindamycin is generally active against Group B streptococci and carries no particular risks for the infant, making it an alternative option for women with penicillin allergy 3.
• The American Academy of Pediatrics and the American College of Obstetricians and Gynecologists recommend clindamycin as an option for prophylaxis in cases of significant maternal penicillin allergy 4.

Intrapartum Antibiotic Prophylaxis for GBS Positive Patients

• Intrapartum antibiotic prophylaxis is the primary recommended approach to prevent perinatal GBS disease, with penicillin, ampicillin, or cefazolin as the recommended options 4.
• The effectiveness of intrapartum antibiotic prophylaxis for preventing early-onset GBS disease is high, with a risk reduction from 4.7% to 0.4% (p = 0.02) 3.
• The optimal window for screening for GBS colonization is between 36 0/7 and 37 6/7 weeks of gestation, and all women with positive screens should receive appropriate intrapartum antibiotic prophylaxis unless a prelabor cesarean birth is performed in the setting of intact membranes 5, 4.

Management of GBS Positive Patients

• Screening for GBS should occur between 36 weeks and the end of the 37th week, and patients with GBS in the urine should be treated at term with antibiotic prophylaxis, independent of the colony count of the culture 6.
• Patients who are GBS-positive with preterm and prelabor rupture of membranes after 34 weeks are not candidates for expectant management, as this population has higher rates of neonatal infectious complications 6.
• Pregnant women with a history of penicillin allergy are now recommended to undergo skin testing, because confirmation of or delabeling from a penicillin allergy can provide both short- and long-term health benefits 4.