Streptococcal Group B Disease

Streptococcal Group B Disease

 

Group B Streptococcus (GBS) is one of the major causes of maternal or neonatal severe infections and sepsis.

Epidemiology

  • Incidence
    • 2/100 live births for neonatal infections
    • 45.5/1000 live birth risk of neonatal GBS infection if mother has one of the risk factors mentioned below
  • Transmission – vertical from mother to neonate in 75% of neonatal cases

Organism

  • Streptococcus Group B are gram-positive cocci that aggregate in clusters or chains
  • Also known as Streptococcus agalactiae

Risk Factors

  • Maternal – preterm delivery, prolonged rupture of membranes, intrapartum fever, prior infant with GBS infection

Clinical Presentation

  • Neonatal infection
    • Early onset (first week of life) – respiratory distress, lethargy and hypotension
    • Late onset (1 week - 3 months) – meningitis is the most frequent manifestation
    • Infection is associated with impaired psychomotor development
  • Adult infection
    • Majority are related to pregnancy and parturition
    • Most common presentation is fever with signs and symptoms of chorioamnionitis or endometritis
    • Other presentations outside of pregnancy include cellulitis, urinary tract infection, pneumonia and endocarditis

Diagnosis

  • Laboratory testing
    • Screening is routinely performed at 35-37 weeks
    • Culture is gold standard test when PCR is not available
    • Rapid diagnostic tests may be limited by false-negative results in patients not heavily colonized

Treatment

  • Intrapartum antibiotic therapy reduces attack rate in mother and neonate

See Also