Group B Streptococcal Disease Prevention and Management

Introduction

Group B Streptococcal (GBS) disease is a significant cause of morbidity and mortality in newborns, and prevention and management strategies are crucial to reduce its impact 1, 2

The American Academy of Pediatrics and the Centers for Disease Control and Prevention recommend maternal intrapartum antibiotic prophylaxis (IAP) as the primary prevention strategy for early-onset GBS disease in women with GBS culture-positive within preceding 5 weeks, GBS status unknown with risk factors, GBS bacteriuria during current pregnancy, and history of a previous infant with GBS disease 1, 2
The preferred antibiotic for IAP is Penicillin G or ampicillin IV for ≥ 4 hours before delivery, according to the American College of Obstetricians and Gynecologists 1

Infants with signs of sepsis should receive a full diagnostic evaluation, including lumbar puncture, and immediate empirical antimicrobial therapy, as recommended by the American Academy of Pediatrics 1
Well-appearing infants born to mothers with chorioamnionitis should receive limited evaluation and empirical antimicrobial therapy, according to the American Academy of Pediatrics 1
Well-appearing infants whose mothers received adequate IAP can receive routine care and observation for 48 hours, and may be discharged after 24 hours if term birth and ready access to medical care, as recommended by the Centers for Disease Control and Prevention 1, 2

The first-line antibiotic for GBS disease is penicillin, with alternatives including ampicillin, ceftriaxone, and clindamycin (if susceptible), according to the Infectious Diseases Society of America 3
Clindamycin should never be used for GBS without susceptibility testing, as recommended by the American Academy of Pediatrics 1
Increasing resistance to macrolides and clindamycin among GBS isolates has been reported, according to the American Academy of Family Physicians 4

Chorioamnionitis is diagnosed by maternal fever, uterine tenderness, fetal tachycardia, maternal tachycardia, and foul-smelling amniotic fluid, and assessment of risk factors for resistant organisms is necessary 2
The Centers for Disease Control and Prevention recommends empirical antibiotic therapy with ampicillin 2g IV initial dose, then 1g IV every 4 hours, and gentamicin 5 mg/kg IV daily dose 1, 2
Add clindamycin 900mg IV when the umbilical cord is clamped in case of cesarean section, but only if susceptibility testing of the mother's GBS isolate has been performed 1, 2
The CDC suggests broader spectrum agents, including piperacillin/tazobactam (Zosyn), for treatment of chorioamnionitis when additional coverage beyond standard regimens is needed, particularly in cases with suspected polymicrobial infection or resistant organisms 2, 5

Suspect septic shock due to chorioamnionitis in the presence of maternal fever (≥38.0°C), maternal tachycardia, fetal tachycardia, uterine tenderness, foul-smelling or purulent amniotic fluid, and signs of shock: hypotension, tachypnea, altered mental status, and oliguria 6
Ensure a patent airway and administer oxygen to maintain saturation >95% 6
Consider intubation if there is severe respiratory distress 6
Establish at least two large-caliber venous access points 6
Administer fluid boluses of 10-60 ml/kg in the first hour, monitoring for signs of overload 6
Continuously monitor hemodynamics (blood pressure, heart rate, saturation) 6
If hypotension persists after fluid resuscitation, initiate vasopressors (norepinephrine as first-line) 6
Consider inotropes if there is myocardial dysfunction 6

All newborns of mothers with chorioamnionitis should receive limited diagnostic evaluation (blood culture, complete blood count with differential and platelet count) and empirical antimicrobial therapy (ampicillin and gentamicin) 1, 2, 5
Observe the newborn in the hospital for at least 48 hours 1, 5
Therapy for the infant should include antimicrobial agents active against GBS, including IV ampicillin, and coverage for other organisms like E. coli 2

Investigate and treat potentially reversible causes, such as pericardial effusion (pericardiocentesis), pneumothorax (thoracocentesis), hypoadrenalism (adrenal hormone replacement), hypothyroidism (thyroid hormone replacement), ongoing hemorrhage (hemostasis), increased intra-abdominal pressure (peritoneal catheter or abdominal decompression), and inadequate control of the infectious focus (review antibiotics, consider IV immunoglobulin) 6
Consider ECMO as a rescue alternative in refractory shock 6