OGCO-C3.9 Prevention of early onset Group B streptococcal (GBS) disease in the newborns

Question 1

When is routine screening for antenatal GBS done?

Answer 1

At 35-37 weeks before deciding whether intrapartum antibiotic prophylaxis is indicated in the current pregnancy, in particular
* History of GBS colonization in previous pregnancies
* Previous baby with GBS colonization but without invasive neonatal GBS disease
* Women with positive GBS culture found not during pregnnacy

Question 2

When should routine GBS screening not be performed?

Answer 2

• History of invasive neonatal GBS diseases: IAP requoired
• GBS bacteriuria in the index pregnancy: IAP required
• GBS colonization in the index pregnancy: IAP required

Question 3

Who is indicated for intrapartum antibiotic prophylaxis?

Answer 3

Question 4

Who is not indicated for intrapartum antibiotic prophylaxis?

Answer 4

Question 5

When is intrapartum antibiotic prophylaxis done?

Answer 5

Antibiotics should be started once rupture of membranes is confirmed or at onset of labour, whichever is earlier

Question 6

What is antibiotics given to women without known penicillin allergy?
Women with known penicillin allergy?

Answer 6

Women without known penicillin allergy: penicillin G 5 million units IV initial dose, then 2.5 million units IV every 4 hourly until delivery (or benzylpenicillin 3g IV loading, then 1.5g every 4 hourly)
Women with known penicillin allergy
* Not at high risk of anaphylaxis: cefazolin, 2g IV initial dose, then 1g IV every 8 hours until delivery
* At high risk of anaphylaxis. GBS susceptible to clindamycin and erythromycin. Clindamycin 900mg IV every 8 hours until delivery or erythromycin 500mg IV every 6 hours until delivery.

GBS resistant to clindamycin or erythromycin or susceptibility unknown: vancomycin 1g IV every 12 hours until delivery

Question 7

How is GBS testing done?
What susceptibility testing done?

Answer 7

2 separate swabs in single special broth culture medium. Take lower vaginal swab at vagina just above introitus. Speculum should not be used for culture collection. Take rectal swab with another swab by inserting through anal sphincter.

Susceptibility testing to penicillin, clindamycin and erythromycin will be routinely performed for all screen positive cases.