Preventing Early onset Group B Streptococcus Infection

Early onset neonatal Group B Streptococcus

Dr Sherrif Shawer Specialty trainee Obstetrics and Gynaecology
Dr Funmi Odusoga Consultant Obstetrician & Gynaecologist

Table of content

1. Background

2. Antenatal management

3. Term Labour

4. Preterm labour

5. Choice of antibiotics

6. Neonates

7. Abbreviations

8. Reference

Background

• GBS is most frequent cause of severe early-onset infection in new-born infants
• GBS present in bowel flora in 20-40% of adults
• Incidence of Early Onset GBS in UK in 2015 is 0.57/1000
• 22% were born prematurely
• 7.4% were reported as having a disability
• Case fatality rate dropped from 10.6% to 5.2%

Antenatal management

• Universal screening is not recommended in the U.K.
• If GBS is positive in previous pregnancy there is a 50% chance of GBS infection in the current pregnancy
• In GBS is present in previous pregnancy either offer intrapartum antibiotics or test for presence of GBS between 35-37weeks gestation or 3-5weeks prior to the anticipated delivery date e.g. 32-34weeks of gestation in women with twins

• If patient is not tested there is 1/800 chance of early onset GBS
• If test is positive there is a 1/400 chance of early onset GBS
• If test is negative there is a 1/5000 chance of early onset GBS

• If previous baby had early onset GBS (0.08% of pregnant women) offer Intrapartum antibiotics
• In patients with Group B streptococcus bacteriuria or GBS Urinary tract infection treat with antibiotics in the antenatal period and give intrapartum antibiotics
• Antenatal treatment is not recommended for GBS cultured from vaginal or rectal swab
• Membrane sweep is not contraindicated in women with GBS
• Antibiotic prophylaxis is not required in caesarean sections with intact membranes

Term Labour

• If there is spontaneous rupture of membranes in patient with positive GBS swab/culture administer intrapartum antibiotics immediately and commence Induction/augmentation of labour as soon as possible
• In the event of Intrapartum pyrexia >38.0C risk of EOGBS is 5.3/1000 (background risk of 0.6/1000) use broad-spectrum antibiotics (Amoxicillin or Cefuroxime)
• Pool birth is not contraindicated provided she is offered appropriate antibiotics

Preterm labour

• Administer intrapartum antibiotics in confirmed preterm labour
• Risk of EOGBS in preterm is 2.3/1000 (4 x risk compared to term)
• Mortality from EOGBS 20-30% vs 2-3% in term babies (10 x risk compared to term)
• If there is prelabour preterm rupture of membranes before 34weeks in the presence of GBS, wait till established labour then administer intrapartum antibiotics.
• If prelabour preterm rupture of membranes occurs in the presence of GBS at 34weeks gestation and above commence induction of labour as soon as possible

Choice of antibiotics

• Antibiotics of choice is Benzylpenicillin-Administer loading dose then offer every 4hours in active labour
• If there is non-anaphylactic allergy to penicillin administer Intravenous Cefuroxime 1.5g then 750mg every 8hours
• If there is anaphylactic allergy to penicillin administer Intravenous vancomycin 1g every 12 hours
• Clindamycin is no longer recommended in the U.K due resistance in 16% of patients

Neonates

• If intrapartum antibiotics is administered >4hours from delivery, no extra observation is required
• If intrapartum antibiotics is not administered do observation in the new born at 0,1,2hrs after birth then 2hourly until 12 hours and discourage early self-discharge from hospital
• 90% of infant with EOGBS will develop signs of infection by 12 hours after birth
• If there is clinical sign of EOGBS, administer penicillin and gentamicin within 1hour
• Signs of early onset neonatal infection are inconsolable crying or listlessness, unusually floppy infant, difficulty in feeding or tolerating feeds, temperature lower than 36C or higher than 38C, rapid breathing and change in skin colour
• If mother had a previous baby with EOGBS, do observation as described above regardless of administration of intrapartum antibiotics

Abbreviations

EOGBS – Early onset group B streptococcus

GBS – Group B streptococcus

Reference

RCOG green-top guideline No.36