Even in developed countries, the infection of streptococcus b (GBS) in newborns, gives doctors many problems. In our previous publication, we have already considered what measures to prevent streptococcal infection offers the American Academy of Pediatrics. The current material will focus on recommendations for the diagnosis and treatment of this serious disease.
Clinical presentation
Newborn infants with GBS EOD may present with signs of illness ranging from tachycardia, tachypnea, or lethargy to severe cardiorespiratory failure, persistent pulmonary hypertension of the newborn, and perinatal encephalopathy.
GBS LOD most commonly occurs as bacteremia without a focus and is often characterized by fever (≥38°C) as well as lethargy, poor feeding, irritability, tachypnea, grunting, or apnea. Infants with LOD meningitis can also have nonspecific signs such as irritability, poor feeding, vomiting, and temperature instability as well as signs suggestive of central nervous systems involvement such as bulging fontanelle or seizures.
Focal syndromes such as pneumonia, bone or joint infection, cellulitis, or adenitis often have findings that point to the site of infection. Osteomyelitis frequently is insidious and may not be associated with fever. Complications are common for meningitis and can include neurodevelopment impairment, hearing loss, persistent seizure disorders, or cerebrovascular disease.
Evaluation for GBS disease is the same as that for all forms of sepsis in the newborn and young infant.Blood culture, lumbar puncture for culture and analysis of CSF, and markers of inflammation are discussed in detail in the AAP clinical reports on management of neonates with suspected or proven early-onset bacterial sepsis.
The evaluation for GBS LOD should also include urine culture. If bone or joint infection is suspected, additional studies can include radiographs, MRI, and bone or joint fluid culture. When meningitis is diagnosed, cranial imaging is often useful to assess for complications such as ventriculitis or brain abscess. Cultures should include testing for antibiotic susceptibility.
Empirical treatment
Antibiotics initiated because of concern for GBS EOD are the same as those for all bacterial causes of EOS until the results of cultures are available. Ampicillin, together with an aminoglycoside, is the primary recommended therapy for infants up to 7 days of age. The empirical addition of broader-spectrum therapy should be considered if there is strong clinical concern for ampicillin-resistant infection in a critically ill newborn, particularly among neonates with very low birth weight.
Ampicillin, together with an aminoglycoside, is the primary recommended therapy for infants up to 7 days of age. The empirical addition of broader-spectrum therapy should be considered if there is strong clinical concern for ampicillin-resistant infection in a critically ill newborn, particularly among neonates with very low birth weight.
Among previously healthy infants in the community, if the infant is not critically ill and there is no evidence of meningitis, ampicillin and ceftazidime together are recommended as empirical therapy for those 8 to 28 days of age; ceftriaxone therapy is recommended under these circumstances for infants 29 to 90 days of age. For all previously healthy infants in the community from 8 to 90 days of age, vancomycin should be added to recommended empirical therapy if there is evidence of meningitis or critical illness to expand coverage.
The choice of empirical therapy among continuously hospitalized preterm infants beyond 72 hours of age is guided by multiple factors, including the presence of central venous catheters and local hospital microbiology. The empirical choice for such infants should include an antibiotic to which group B streptococci are susceptible, such as a β-lactam, cephalosporin, or vancomycin. When group B streptococci are identified in culture, penicillin G is the drug of choice, with ampicillin as an acceptable alternative therapy.
Recommended Intravenous Antibiotic Treatment Regimens for Confirmed Early- and Late-Onset GBS Bacteremia and Meningitis
GA ≤34 wk
PNA ≤7 d
PNA >7 d
GA >34 wk
PNA ≤7 d
PNA >7 d
Bacteremia
Ampicillin
50 mg/kg every 12 h
75 mg/kg every 12 h
50 mg/kg every 8 h
50 mg/kg every 8 h
Penicillin G
50.000 U/kg every 12 h
50.000 U/kg every 8 h
50.000 U/kg every 12 h
50.000 U/kg every 8 h
Meningitis
Ampicillin
100 mg/kg every 8 h
75 mg/kg every 6 h
100 mg/kg every 8 h
75 mg/kg every 6 h
Penicillin G
150.000 U/kg every 8 h
125.000 U/kg every 6 h
150.000 U/kg every 8 h
125 Од / кг кожні 6 год
GA ≤34 wk
Bacteremia
Ampicillin
Penicillin G
PNA ≤7 d
50 mg/kg every 12 h
50.000 U/kg every 12 h
PNA >7 d
75 mg/kg every 12 h
50.000 U/kg every 8 h
Meningitis
Ampicillin
Penicillin G
PNA ≤7 d
100 mg/kg every 8 h
150.000 U/kg every 8 h
PNA >7 d
75 mg/kg every 6 h
125.000 U/kg every 6 h
GA >34 wk
Bacteremia
Ampicillin
Penicillin G
PNA ≤7 d
50 mg/kg every 8 h
50.000 U/kg every 12 h
PNA >7 d
50 mg/kg every 8 h
50.000 U/kg every 8 h
Meningitis
Ampicillin
Penicillin G
PNA ≤7 d
100 mg/kg every 8 h
150.000 U/kg every 8 h
PNA >7 d
75 mg/kg every 6 h
125 U/kg every 6 h
Multiple Births
When invasive GBS infection occurs in an infant who is 1 of multiple births, the birth siblings should be observed carefully for signs of infection and treated empirically if signs of illness occur. There is no evidence to support full antibiotic treatment courses in the absence of confirmed GBS disease.
Recurrent GBS Disease
Recurrent neonatal and young infant GBS disease can occur after completed appropriate treatment of the primary infection.103,104 Authors of a population-based study conducted in Japan53 during 2011 to 2015 found that recurrence occurred in 2.8% of cases of neonatal GBS infection. Recurrent cases were identified 3 to 54 days after completion of the therapy for the first occurrence. Recurrent cases are generally caused by the same GBS serotype that caused the primary infection, and persistent mucosal colonization and poor neonatal antibody responses to the first infection likely contribute to the pathogenesis of recurrent infection. Recurrent disease is not preventable by extension of recommended antibiotic courses nor by the addition of rifampin to eradicate mucosal colonization. Parents should be counseled about the possibility of recurrent GBS disease after treatment of both GBS EOD and LOD.
Future Directions
Intrapartum Antibiotics, the Microbiome, and Childhood Health
GBS IAP and the administration of intrapartum antibiotics because of concern for maternal intraamniotic infection combined result in approximately 30% of pregnant women receiving antibiotics around the time of delivery. The composition of the gut microbiota develops and diversifies from birth through early childhood, and disruption of the microbiota during this critical period may have enduring health consequences. Perinatal antibiotic administration is associated with abnormal host development in animal models.
Human epidemiological studies have associated early infant antibiotic exposures with increased risks of atopic and allergic disorders as well as increases in early childhood weight gain.
GBS Vaccine Development
Multiple gaps remain in GBS disease prevention. Neonatal EOD continues to occur in the United States, primarily among preterm infants, term infants born to women with cultures negative for antenatal GBS, and infants born to mothers with reported β-lactam allergy that precludes maximally effective IAP.
The incidence of GBS LOD has not been affected by IAP. In addition, group B Streptococcus is a cause of stillbirth and of invasive infection among pregnant and postpartum women as well as among the elderly and those whose health is compromised by diabetes or malignancy.
Furthermore, GBS disease is a worldwide problem, particularly among resource-limited countries where IAP is not a readily available preventive strategy.
Effective, multivalent vaccines administered to pregnant women and at-risk nonpregnant adults could potentially prevent many of these issues. Preclinical and human phase I and II studies have been completed revealing the safety and immunogenicity of glycoconjugate GBS vaccines. Current ABCs reveals that 99% of infections are caused by 6 GBS serotypes, suggesting that a hexavalent vaccine could be widely effective.
