1. Jeanine Spielberger MD 9/23/2013 INTRAPARTUM ANTIBIOTIC PROPHYLAXIS FOR GROUP B STREPTOCOCCAL INFECTION

2.  Recite indications and non-indications for intrapartum GBS prophylaxis to prevent early onset GBS disease.  Select appropriate antibiotics for intrapartum GBS prophylaxis.  Manage a patient with suspected preterm labor and unknown GBS status. GOALS AND OBJECTIVES

3.  Early-onset GBS Disease is leading cause of neonatal sepsis in U.S.  Annual incidence in 2008: 0.28 cases / 1,000 live births  Estimated 1,200 cases in 2008  Case fatality rate  1970s: As high as 50%  4-6% in recent years WHY THIS TOPIC? "Image courtesy of Praisaeng/ FreeDigitalPhotos.net".

4.  Gram positive, beta hemolytic bacteria  Common colonizer of human gastrointestinal and genitourinary tracts  Recognized as causing disease in humans in the 1930s  Emerged as most common cause of sepsis and meningitis in infants <3 months in the 1970s GROUP B STREPTOCOCCUS

5. MOTHER TO INFANT TRANSMISSION OF GBS Image courtesy of Jomphong at FreeDigitalPhotos.net GBS colonized mother 50% non-colonized newborn50% colonized newborn 98% asymptomatic 2% SICK

6. Indicated? INDICATIONS FOR INTRAPARTUM ANTIBIOTIC PROPHYLAXIS Image courtesy of Anitapeppers at morguefile.com

7.  Previous infant with invasive GBS disease  GBS bacteriuria current pregnancy  Positive vaginal-rectal GBS screening culture current pregnancy  Unknown GBS status at onset of labor and any of the following:  Delivery <37 weeks’ gestation  ROM >/=18 hours  Intrapartum test positive for GBS  Intrapartum temperature >/= 100.4°F INDICATIONS FOR INTRAPARTUM ANTIBIOTIC PROPHYLAXIS Indicated?

8. Not Indicated? NONINDICATIONS FOR INTRAPARTUM ANTIBIOTIC PROPHYLAXIS Image courtesy of Anitapeppers at morguefile.com

9.  Colonization with GBS during a previous pregnancy*  GBS bacteriuria during a previous pregnancy*  Negative vaginal-rectal GBS screening culture in late gestation during current pregnancy, regardless of intrapartum risk factors  Cesarean delivery before onset of labor with intact amniotic membranes NONINDICATIONS FOR INTRAPARTUM ANTIBIOTIC Not Indicated *unless an indication for GBS prophylaxis is present for current pregnancy

10.  Penicillin G  5 million units IV, followed by 2.5 - 3.0 million units IV every four hours  Ampicillin is an acceptable alternative RECOMMENDED ANTIBIOTICS

11.  ? RECOMMENDED ANTIBIOTICS- PENICILLIN ALLERGY "Image courtesy of arztsamui/ FreeDigitalPhotos.net".

12.  NOT high risk for anaphylaxis- Cefazolin RECOMMENDED ANTIBIOTIC- PENICILLIN ALLERGIC "Image courtesy of moggara12/ FreeDigitalPhotos.net".

13.  High risk for anaphylaxis  Clindamycin  susceptible to clindamycin AND erythromycin.  sensitive to clindamycin and resistant to erythromycin, IF inducible clindamycin resistance testing negative.  Vancomycin  Susceptibility to clindamycin and erythromycin is unknown  resistant to clindamycin or positive for inducible clindamycin resistance.  Erythromycin- no longer an acceptable alternative RECOMMENDED ANTIBIOTIC- PENICILLIN ALLERGIC

15.  In patients with threatened preterm delivery:  Give prophylaxis at hospital admission if:  GBS colonization status is unknown OR  they had a positive screen within five weeks  Discontinue antibiotics If :  admission screening results are negative for GBS OR  it is determined that a patient is not in true labor- THREATENED PRETERM DELIVERY

16. Infants born preterm  50% screened prior to admission  18% of GBS unknown screened on admission  Preterm 20% less likely to receive IAP when indicated than term MISSED PREVENTION OPPORTUNITIES Van Dyke, NEJM 2009, 360: 2626- 36.

17. Penicillin-allergic women:  Only 14% at low risk for anaphylaxis received cefazolin  70% at low risk for anaphylaxis received clindamycin even though:  <5% had susceptibility testing MISSED PREVENTION OPPORTUNITIES Van Dyke. NEJM, 2009, 360: 2626-36.

18. THERE’S AN APP FOR THAT!

19.  PENICILLIN is first line for intrapartum prophylaxis against early onset GBS disease.  CEFAZOLIN provides adequate prophylaxis in women who have PCN allergy who are LOW RISK for anaphylaxis.  Clindamycin should be used ONLY if appropriate susceptibility testing has been done, otherwise use vancomycin.  Obtain GBS testing and start antibiotics in ANY woman who is admitted in preterm labor who does not have an available GBS result.  Indications and non-indications for intrapartum prophylaxis are available through CDC app and web site. CONCLUSIONS