GBS_Flashcards
What is Group B Streptococcus (GBS)?
GBS is the most common cause of early-onset severe infection in the neonatal period.
How prevalent is GBS in mothers?
Around 20-40% of mothers have GBS present in their bowel flora and may be thought of as ‘carriers’ of GBS.
When may infants be exposed to maternal GBS?
Infants may be exposed to maternal GBS during labour and subsequently develop potentially serious infections.
What are the risk factors for GBS infection?
Prematurity, prolonged rupture of the membranes, previous sibling GBS infection, maternal pyrexia (e.g. secondary to chorioamnionitis).
What did the Royal College of Obstetricians and Gynaecologists (RCOG) publish regarding GBS?
RCOG published guidelines on GBS in 2017.
Should universal screening for GBS be offered to all women?
No, universal screening for GBS should not be offered to all women.
Is a maternal request an indication for GBS screening?
No, a maternal request is not an indication for screening.
What should women who’ve had GBS detected in a previous pregnancy be informed about?
They should be informed that their risk of maternal GBS carriage in this pregnancy is 50%.
What should be offered to women who’ve had GBS detected in a previous pregnancy?
They should be offered intrapartum antibiotic prophylaxis (IAP) OR testing in late pregnancy and then antibiotics if still positive.
When should swabs for GBS be offered if necessary?
Swabs should be offered at 35-37 weeks or 3-5 weeks prior to the anticipated delivery date.
Who should be offered IAP?
IAP should be offered to women with a previous baby with early- or late-onset GBS disease, in preterm labour regardless of GBS status, and women with pyrexia during labour (>38ºC).
What is the antibiotic of choice for GBS prophylaxis?
Benzylpenicillin is the antibiotic of choice for GBS prophylaxis.
summarise
Group B Streptococcus
Group B Streptococcus (GBS) is the most common cause of early-onset severe infection in the neonatal period. It is thought around 20-40% of mothers have GBS present in their bowel flora and may therefore be thought of as ‘carriers’ of GBS. Infants may be exposed to maternal GBS during labour and subsequently develop potentially serious infections.
Risk factors for Group B Streptococcus (GBS) infection:
prematurity
prolonged rupture of the membranes
previous sibling GBS infection
maternal pyrexia e.g. secondary to chorioamnionitis
Management
The Royal College of Obstetricians and Gynaecologists (RCOG) published guidelines on GBS in 2017.
The main points are as follows:
universal screening for GBS should not be offered to all women
the guidelines also state a maternal request is not an indication for screening
women who’ve had GBS detected in a previous pregnancy should be informed that their risk of maternal GBS carriage in this pregnancy is 50%. They should be offered intrapartum antibiotic prophylaxis (IAP) OR testing in late pregnancy and then antibiotics if still positive
if women are to have swabs for GBS this should be offered at 35-37 weeks or 3-5 weeks prior to the anticipated delivery date
IAP should be offered to women with a previous baby with early- or late-onset GBS disease
IAP should be offered to women in preterm labour regardless of their GBS status
women with a pyrexia during labour (>38ºC) should also be given IAP
benzylpenicillin is the antibiotic of choice for GBS prophylaxis
A 28-year-old woman who is 34 weeks pregnant is diagnosed with a urinary tract infection after routine dipstick testing. Laboratory analysis shows group B streptococcus to be the cause and this is treated with a short course of oral antibiotics. How should this woman be managed with respect to delivering her baby in a few weeks time?
Neonatal antibiotics within 1 hour of birth
Caesarean section at 38 weeks
No additional measures needed
Intrapartum antibiotics
Vaginal swabs in early labour with treatment based on this result
Group B streptococcus (GBS) bacteriuria is associated with an increased risk of chorioamnionitis and neonatal sepsis. The Royal College of Obstetricians and Gynaecologists states that women with GBS bacteriuria should therefore be offered intrapartum antibiotics in addition to appropriate treatment at the time of diagnosis. For non-penicillin-allergic patients intrapartum antibiotics will consist of intravenous benzylpenicillin given as soon as possible after the start of labour, then at 4-hourly intervals until delivery.
Postnatal antibiotic treatment is not indicated unless there are signs of neonatal infection. Caesarean section is not indicated.
[RCOG Green-top Guideline No. 36]
