RANZCOG - GBS

Question 1

what are the maternal colonisation rates of GBS?

Answer 1

10-30%

Question 2

what is the incidence of early onset GBS infection?

Answer 2

untreated up to 4/1000

Question 3

what is the case fatality rate of GBS?

Answer 3

14%

Question 4

How much can the use of intrapartum antibiotics protect against EOGBS?

Answer 4

reduces by 80%

Question 5

list clinical risk factors for early onset GBS

Answer 5

• spontaneous labour <37/40
• ROM >18 hours
• maternal fever >38 deg
• previous infant with EOGBS or late onset GBS
• GBS bacteruria during current pregnancy
• known carriage of GBS during current prgnancy
• clinical diagnosis of chorioamnionitis
• other twin with current EOGBS

Question 6

what does universal screening program for maternal GBS mean and list two advantages?

Answer 6

• use of universal screening rather than risk based screening to assess for maternal carriage of GBS
• vaginal +/- anorectal culture at 36/40 = universal culture based screening
• advantages - reduces EOGBS when cf risk based screening

Question 7

when requesting GBS screening in a pregnant woman what should you write on the form?

Answer 7

• specify that collection is for screening rather than routine culture
• this is because specific culture conditions required
• if allergic to penicillin this needs to be written on form

Question 7

when requesting GBS screening in a pregnant woman what should you write on the form?

Answer 7

• specify that collection is for screening rather than routine culture
• this is because specific culture conditions required
• if allergic to penicillin this needs to be written on form

Question 8

when requesting GBS screening in a pregnant woman what should you write on the form?

Answer 8

• specify that collection is for screening rather than routine culture
• this is because specific culture conditions required
• if allergic to penicillin this needs to be written on form

Question 9

when requesting GBS screening in a pregnant woman what should you write on the form?

Answer 9

• specify that collection is for screening rather than routine culture
• this is because specific culture conditions required
• if allergic to penicillin this needs to be written on form

Question 10

why is it recommended that culture is taken at 36/40?

Answer 10

GBS carriage fluctuates over time
if taken at 36/40 then more likely to be relevant in labour
5/52 becomes less relevant

Question 11

which antibiotics should be given for GBS protection in labour?

Answer 11

• IV penicillin
• ampicilin
• cefazolin, vancomycin, clindamycin are alternatives if penicillin allergic

Question 12

if a woman is considered high risk for GBS and labours or SROMs prior to planned CS how would you manage?

Answer 12

• give antibiotics