CAMBRIDGE HEALTH ALLIANCE GYNECOLOGY & OBSTETRICS

MORBIDITY & MORTALITY CONFERENCE 1/2013: GBS SEPSIS

CLINTON PONG, PGY-3 FAMILY MEDICINE

Privileged & Confidential: Subject to Peer Review and Medical Review Protections, O.C.G.A. 31-7-

130 et seq. and 31-7-140 et seq.

GBS prevalence GBS swab technique and collection GBS tx

CHA guidelines 2002-2010 changes

Privileged & Confidential: Subject to Peer Review and Medical Review Protections, O.C.G.A. 31-7-

130 et seq. and 31-7-140 et seq.

Privileged & Confidential: Subject to Peer Review and Medical Review Protections, O.C.G.A. 31-7-

130 et seq. and 31-7-140 et seq.

Privileged & Confidential: Subject to Peer Review and Medical Review Protections, O.C.G.A. 31-7-

130 et seq. and 31-7-140 et seq.

In the 1970s, GBS had a case-fatality ratio as high as 50%, with an estimated 7500 cases/year

GBS = Group B strep = S. agalactiaeEarly-onset GBS disease = <1wk

Sepsis & PNA most commonMeningitis less common

Late-onset GBS disease = >1wk-3mo

Now with active prevention, there is only 4-6% overall case-mortality,

20-30% of preterm infants compared to 2-3% of full-term infants.

n=10439

Early onset: vertical transmission from the vagina of a colonized womanGI/GYN colonizers: ~10-30% of pregnant woman have (+)GBS swabsGU colonizers: 2-7% of pregnant women have (+)GBS bacteriuria Threshold is >105 CFU for most studies; little data on <104 CFU

GBS swab technique GBS collection and cx medium/PCR:

Direct (50% false negative)Selective (Sn 83.3-84.3%)

○ TransVag (+gentamicin)○ Lim Broth (+colistin)

CAMP test vs serologicChromogenic agar

NAAT/PCRSn 90.7-95.8%

Selective broth + PCRSn 92.5-100%

Privileged & Confidential: Subject to Peer Review and Medical Review Protections, O.C.G.A. 31-7-

130 et seq. and 31-7-140 et seq.

Privileged & Confidential: Subject to Peer Review and Medical Review Protections, O.C.G.A. 31-7-

130 et seq. and 31-7-140 et seq.

0.2% resistance

86-89% effective

0.7-4% allergic reactions

0.05% resistance

0% resistance 13-20% resistance

25-32% resistance

Key changes from 2002 guidelines:Adequate tx = > 4hr of IV PCN/amp/Cefazolin

○ Well appearing 35-36 wk = no routine eval needed

Inadequate tx = everything else○ Well appearing infants = 48 hr obs

Clinical signs of sepsis are more Sn than lab tests

○ <37+0 or ROM >18hr = ltd eval +48hr obsSn of CBC is better at 6-12hr of life than 0hr

Privileged & Confidential: Subject to Peer Review and Medical Review Protections, O.C.G.A. 31-7-

130 et seq. and 31-7-140 et seq.

Case studies on GBS1984: 15 infants / 4 year period

○ All <1000g, <28wk GA○ 3 infants SROM > 24hr

“A history of intact membranes at the time of delivery does not exclude a diagnosis of an intrauterine infection with [group B strep] … highlighting the importance of routine bacteriologic studies of all perinatal deaths”

Privileged & Confidential: Subject to Peer Review and Medical Review Protections, O.C.G.A. 31-7-

130 et seq. and 31-7-140 et seq.

Case studies on GBS with intact membranes 1988: 16 infants / 3 years

6 infants had intact membranes Review of reports from OB and peds

literature reveal that 10-50% of GBS infections occur in this manner

Privileged & Confidential: Subject to Peer Review and Medical Review Protections, O.C.G.A. 31-7-

130 et seq. and 31-7-140 et seq.

New changes on the horizonGBS detection prior to delivery

○ NAAT needs enrichment○ Not yet feasible in triage setting

GBS vaccine: ○ Type-III capsular polysaccharide antibody

Responsible for most meningitis and burden of early-onset GBS disease

Clinical trials are ongoing

Privileged & Confidential: Subject to Peer Review and Medical Review Protections, O.C.G.A. 31-7-

130 et seq. and 31-7-140 et seq.

References ACOG Practice Bulletin: Management of Stillbirth. No 102,

March 2009. ACOG Practice Bulletin: Use of Prophylactic Antibiotics in L&D

June 2011. MMWR Prevention of Perinatal Group B Streptococcal

Disease. Revised Guidelines from CDC, 2010 www.cdc.gov/mmwr/cmw/conted.html

Desa, DJ., et al. Intrauterine infections with group B beta-haemolytic streptococci. Br J Obstet Gynaecol 1984;91:237-9 PMID 63667810

Katz V., et al. Perinatal GBS infections across intact amniotic membranes. J Reprod Med. 1988 May;33(5):445-9 PMID 3290476

Schuchat, A. Epidemiology of GBS Disease in the US: Shifting Paradigms. Clin Microbiol Rev. 7/1998;11:3:497-513

Privileged & Confidential: Subject to Peer Review and Medical Review Protections, O.C.G.A. 31-7-

130 et seq. and 31-7-140 et seq.