WELCOME APPLICANTS!Morning Report: Friday, November 4th, 2011

Geaux Tigers!!!! Roll Tide Roll…around the bowl and down the hole!

Group B Streptococcal Infections

Background Encapsulated gram-positive diplococcus

Currently 10 known serotypes Major cause of bacterial infections in

pregnant women in the perinatal period Bacteremia Amnionitis Endometritis UTIs

Also causes focal and systemic infections in newborns

Background RARE cause of infection in older children and

non-pregnant adults Three types of neonatal infection:

Early-onset disease (EOD): occurs within the first week of life (usually within 72h)

Late-onset disease (LOD): occurs between 1 and 4 weeks of life

Late,late-onset disease: occurs between 1 and 6 months of age Can be associated with immunodeficiency Most often seen in premature infants

Epidemiology Common inhabitant of the maternal GI

and genital tract Colonizes ~20% of pregnant women Increased risk of colonization

Low SES Black race Age <20 yo

Cultures obtained after 35-37 wga have a negative predictive value of 97% and a positive predicitve value of 89%

Epidemiology Women identified as GBS+ through

culture-based screening are 25 times more likely to deliver an infant with EOD.

Identification of colonized women along with intrapartum antibiotic prophylaxis has 80% decrease in EOD (since 2002)

Pathogenesis

Maternal colonization with GBS in the GI/GU tract and transmission to the infant either in utero or during passage through the birth canal

Horizontal transmission either in the nursery or at home

Early-onset Disease Late-onset Disease

*Clinical Aspects

Spectrum of EOD: bacteremia septic shock; can also see persistent fetal circulation or RDS

Diagnosis Non-specific testing

Leukocytosis/ left shift CSF pliocytosis Elevated acute phase reactants Lab signs of complications of sepsis (DIC, acidosis,

hepatic injury, BM failure) Isolation of organism from normally sterile site

BCx CSF Cx Joint space Cx

Diagnosis Latex agglutination

Can identify GBS polysaccharide Ag in isolates from culture as well as biologic fluids

Culture more sensitive Should be used when either mother or

infant has been treated with ABx prior to culture

Treatment Empiric treatment for EOD

Ampicillin (100-150mg/kg/d) AND Aminoglycoside

Empiric Treatment for LOD Ampicillin PLUS Cefotaxime OR Ceftriaxone

Continued for several days until GBS has been isolated (with sensitivities) and there is a good clinical response or the CSF becomes sterile

Treatment Meningitis

Antibiotic changes: Penicillin G 300,00U/kg/d Ampicillin 200-300mg/kg/d

Some experts believe a second LP 24-48h after initiation of therapy aids in management and prognosis

Treatment Duration

Bacteremia/ PNA/ soft tissue infection 10 days

Meningitis/ arthritis 14-21 days

Osteomyelitis/ endocarditis 21-28 days

*Repeated LPs and diagnostic imaging if response to therapy is unclear

An Ounce of Prevention…

Step 1…Testing! Universal screening at 35-37wga Options for GBS identification

Culture of maternal vaginal/ rectal swabs Positive identification from chromogenic

agar media Nucleic acid amplification tests (NAATs)

Step 2…Who Needs Prophylaxis? Prophylaxis indicated with:

Previous infant with invasive GBS GBS bacteruria during the current

pregnancy Positive GBS screen during the current

pregnancy Unknown GBS status AND:

Gestation <37 wks ROM> 18h Intrapartum fever >38.0

Step 3…What to Give? Penicillin is the agent of choice, ampicillin is

an acceptable alternative PCN-allergic women without a history of severe

reaction to PCN (anaphylaxis) or cephalosporins should receive cefazolin

PCN-allergic women with high risk of anaphylaxis should receive clindamycin if their isolate is susceptible or Vancomycin if it’s resistant

Adequate IAP= at least 4 hours of penicillin, ampicillin or cefazolin All others inadequate (including Vanc and Clinda)

The Old Nomogram

The New Nomogram

Prognosis Mortality=5% Major determinates of outcome

Severe prematurity Septic shock

Periventricular leukomalacia may develop as a sequela of septic shock without meningitis significant DD

Prognosis After meningitis:

Cortical blindness Spasticity Global intellectual disability

Minor or severe Deafness Motor defecits

How would you proceed? Ex 38 wga well-appearing F whose mother had a

previous infant with GBS meningitis. Mom received 3 doses of Clindamycin before delivery. ROM 15 hours PTD Inadequate IAP Observation x48h

Ex 36 wga M born via C-section. ROM at delivery. Mother was GBS+ by screening at 35wga. No IAP was given. The infant has a normal newborn exam. Routine newborn care IAP not indicated when C/S

happens before the onset of labor (membrane are intact)

How would you proceed? Ex 40 wga healthy M whose mother

broke out in a rash when she received PCN as a child. She was GBS+ by screening and received 1 dose of cefazolin 4h PTD. Adequate IAP Observe for 48 hours, but

may be discharged after 24h if all other criteria met and close f/u with PCP possible

How would you proceed? Ex 37 wga M whose mother was GBS+

treated with 4 doses of ampicillin prior to delivery. Mom had a temp of 101.5 during delivery, and you overheard the OB resident saying they were very suspicious of chorioamnionitis. Limited evaluation (CBC, BCx) and empiric

antibiotics until clinical course and lab evaluation can exclude sepsis (48h)

Love them Tigers!!!