Objectives

 Describe the epidemiology of Group B Update: Perinatal Group B , including incidence and Streptococcal Disease risk factors.  Discuss the latest treatment & Michele B. Zitzmann, M.H.S., MT(ASCP) prevention guidelines for perinatal LSUHSC Dept. of Clinical Laboratory Sciences Group B streptococcal disease. New Orleans CLPC Spring, 2017

Group B Streptococcus (GBS) Group B Streptococcus (GBS)

 Leading bacterial infection associated with  Currently: Remains the leading illness and death among newborns in the infectious cause of morbidity & mortality U.S. among newborns in the U.S. • Prior to active prevention activities (1996): – CDC estimates 1,200 cases of GBS –8,000 – 12,000 cases of GBS sepsis & sepsis & meningitis in newborns each year meningitis in newborns each year (U.S.) (U.S.) –Approximately 2,000 deaths – Approximately 70% of cases are among –Direct medical costs: $300 million/year babies born at term (>37 weeks gestation)

Group B Streptococcus

 Gram positive cocci – Short chains in clinical specimens – Longer chains in culture  Blood – Gray-white mucoid colonies – Small zone of beta

1 S. agalactiae: Blood Agar Plate Beta-Hemolysis

Streptococcus agalactiae CAMP test

 Laboratory Tests:  Used to presumptively identify group B – : Negative streptococci – 6.5% NaCl: No growth  Named after the individuals who discovered the reaction – CAMP test: Positive –Christie, Atkins, & Munch-Petersen – Bile Esculin: Negative  is inoculated onto blood – Hippurate hydrolysis: Positive agar plate  Unknown streptococcal isolate inoculated perpendicularly to S. aureus inoculum

Positive CAMP test Positive & Negative CAMP test

2 Hippurate Hydrolysis Lancefield Classification

 Differentiates S. agalactiae from other  Developed in the 1930’s beta-hemolytic streptococci  Rebecca Lancefield  Inoculate sodium hippurate with colony;  Differentiation of C carbohydrate in cell incubate 2 hours at 35oC; add ninhydrin wall reagent (indicator); incubate 10-15 min  Streptococcus agalactiae – Group B  Deep purple color = positive  Only one organism in Group B category result  Names used interchangeably

Schematic Representation: Source & Transmission Streptococcal Cell Wall  Normal flora of bowel, vagina, or throat  Many “carriers” of GBS (asymptomatic)  10 - 30% of all pregnant women carry GBS in the rectum or vagina  Fetus may come into contact with GBS before or during birth (vertical transmission)  Cesarean section does NOT eliminate risk

Maternal to Infant Transmission Clinical Disease

 If mother carries GBS:  Sepsis – most dramatic & devastating – 1 of every 100-200 babies will be affected complication • 1 in 4,000 chance if IAP is administered  Pneumonia - early-onset only; 0-5 days – 80% of the cases occur in the first week of  Meningitis – can be early-onset or late- life (Early-onset disease – EOD) onset (5-90 days) – Most cases apparent a few hours after birth  Neurologic - hearing and/or visual loss; – Premature babies are more susceptible impaired mental abilities

3 Signs & Symptoms – Early Onset

 Asymptomatic at birth  Within first 24 hours of life: – Tachypnea – Mottling of skin – Lethargy – Hypotension – Irritability – Decreased feeding – Jaundice – Cyanosis  60 – 80% of infections occur within 12 hours of life  Mechanical ventilation often required

GBS Disease in Infants

90 80 70 60 50 40 30 20

Percent of cases of Percent 10 0 < 1 1-3 1234567891011 wk wk Age (months)

Early-Onset Risk Factors for Early-Onset Neonatal GBS Disease GBS Disease

90  Maternal GBS colonization – primary risk 80 70  Obstetric: prolonged rupture of 60 50 membranes (>18 hours), preterm labor 40 (<37 weeks), intrapartum fever (100.4o F) 30 20  Percent of cases Previous infant with GBS disease 10 0  Demographic (age < 20 yrs, African- 0123456 American) Age (days)

4 Obstetric Risk Factors Among Women with GBS Infants Prevention Strategies: 1992-96

n = 245  American College of Ob & Gyn (ACOG) – No prenatal screening * no obstetric risk – Prophylaxis for women with OB risk factors factors * obstetric risk  American Academy of Pediatrics (AAP) 46% factors – Universal prenatal screening 54% – Prophylaxis for carriers with OB risk factors  EITHER approach expected to prevent * premature < 37 wk, ROM > 18 hr, temp > 100.4o F (38o C) 60-75% of early-onset disease

Prevention: Intrapartum Antibiotic Impact of Prevention Early-Onset GBS Disease by Year and Prophylaxis (IAP) Percent Hospitals with a GBS Policy -- Atlanta, GA

ACOG Tech Bulletin AAP Guidelines Consensus  Antibiotics administered IV after onset 2.5 60

Meeting y of labor or membrane rupture, but 2 50 before delivery Provider Practice Hospital 40 1.5 Survey Site Visits  Most likely method for preventing GBS 30 1 CDC Draft  Penicillin is drug of choice; ampicillin Guidelines (Dec) 20 Consensus 0.5 10 also used Guidelines (May) % Hospitals with GBS Polic % Hospitals GBS with Cases per 1000 live births per Cases 0 0 1989 1990 1991 1992 1993 1994 1995 1996 1997 Year

Barriers to Effective GBS Prevention Statistics Disease Prevention - Initially

 CDC and Prevention’s surveillance data  63% of clinicians collected prenatal indicate that early-onset GBS disease cultures for GBS declined by 65% between 1993 and 1998 BUT: (in areas with continuous data)  91% used suboptimal sites (not vag/rectal)  In 1998, an estimated 3,900 neonatal  Few clinicians knew what media their labs infections and 200 deaths were prevented used  <10% of 200 labs surveyed were using optimal media (selective broth)

Jafari et al., Pediatr Infect Dis J 1995;14:662-7. Whitney et al., OB GYN 1997;89:28-32.

5 Women Screened for GBS Prevention Strategies: 2002 (1998-9) vs. (2003-4)

 Universal culture screening for all pregnant women at 35-37 weeks gestation  Implementation was rapid & widespread  However, only 50.3% of women delivering preterm had known GBS status  Only 63.4% received prophylaxis

Women Who Received IAP Prevention Strategy: 2010 (1998-9) vs. (2003-4) Risk factors: Give • Previous infant w/GBS disease YES intrapartum • GBS this pregnancy penicillin • Delivery < 37 wks gestation NO GBS+ Give Collect rectal & vaginal swab at 35-37 wks intrapartum Not done, incomplete, or penicillin results unknown GBS- Risk factors: • Intrapartum fever > 100.4oF YES Give • ROM > 18 hrs intrapartum penicillin NO No intrapartum prophylaxis needed

CDC’s Recommendations for Advantages of Prevention Strategy Prenatal GBS Cultures

 Optimizes prenatal screening Optimize cultures: – Fewer false negatives  Site: vagina and rectum – Less pressure on physicians to treat – Single swab or two swabs  Antibiotics to all GBS carriers – Through anal sphincter – Antibiotics start earlier before development  Cervical, perianal, & perineal – NOT of risk factors acceptable – Adequate time for antibiotic effectiveness  Timing: 35 to 37 weeks  Processing: selective broth medium

6 Specimen Transport

 Inoculate swabs into non-nutritive transport medium – Commercially available (Stuart’s or Amie’s)  Specimens in media may remain viable at RT for up to 4 days, however… – Results most sensitive when processed within 24 hours & refrigerated  Specimens should be properly labeled – GBS specimen, penicillin allergy status

Laboratory Testing Laboratory Testing

 Inoculate swabs into selective broth  Pigmented enrichment broth – Todd-Hewitt broth with nalidixic acid – StrepB Carrot Broth (15 µg/ml) and EITHER colistin (10 µg/ml) or gentamicin (8 µg/ml) – Commercially: SBM or LIM broth  Incubate broth 18-24 h. Subculture to sheep blood agar plate

Laboratory Testing continued Slide Agglutination Tests

 Inspect and ID suggestive organisms – B-hemolytic or nonhemolytic, Gram+, catalase-  If GBS not identified after 18-24h on sheep BAP, reincubate and inspect at 48h  Various GBS Ag detection tests (slide agglutination, genetic probes, fluorescent antibodies) may be used for specific identification or CAMP test for presumptive identification

7 Results: Agglutination Commercial Tests PCR (Nucleic acid amplification tests – NAAT)

 Can be used for GBS screening at 35-37 weeks if performed from an enrichment broth (incubated for 18-24 hours)  Cannot be performed directly from vaginal-rectal swab unless woman with unknown GBS status presents in active labor & has no risk factors A positive agglutination A negative agglutination GBS is present GBS is not present

Photo courtesy of Dr. Richard Facklam, CDC

Laboratory Testing - Urine

 GBS bacteriuria – A marker for heavy colonization – A risk factor for having an infant with early- onset GBS disease – Colony count cutoff of 104 cfu/mL or higher • New guidelines • Prevents burden of reporting all colony counts

GBS Carriage by Culture Site

Women in Vagina (%) Anorectum Both study (#) (%) (%) 789 10 18 21

94 18 28 31

301 11 14 18

8 GBS Carriage by Culture Method Intrapartum Prophylaxis

Women in Selective Blood agar  Penicillin study (#) broth (%) plate (%) – 5 million units IV load, then 2.5 million units IV every 4h until delivery 166 34 14  Ampicillin – 2 g IV load, then 1g IV every 4h until delivery 952 17 9 – Acceptable alternative, but broader spectrum may select for resistant organisms  Penicillin allergy 383 20 13 – Clindamycin or Erythromycin (increase in resistance) – Vancomycin - if resistant

Timing of Intrapartum Ampicillin Diagnostic Evaluation of Infants and Transmission of GBS Born to Mothers with IAP

Interval between No. of GBS No. (%) GBS  Full Evaluation Ampicillin and carrier mothers colonized babies – CBC & Differential birth – Controls 209 98 (47) (no Ampicillin) – +/- Chest X-ray < 1 hour 30 13 (43) – +/- Lumbar puncture 1-2 hours 36 7 (19)  Limited Evaluation – CBC & Differential 2-4 hours 80 2 (2.4) – Blood culture >4 hours 105 1 (0.9)

Sample Algorithm for Management of Newborn if Maternal IAP Case Study #1

Maternal IAP for GBS?  28 year old female Yes • Full diagnostics evaluation Symptoms of sepsis in newborn? • Empiric therapy  First pregnancy No < 35 wks  Vaginally delivers 5 pound, 15 ounce Gestational age • Limited evaluation • Observe at least 48 hrs male 35 wks+ • If sepsis suspected, full Duration of maternal < 4 hrs or diagnostic evaluation and  37 weeks gestation IAP before delivery < 2 doses empiric therapy  Normal apgar scores at birth >4 hrs or >2 doses  Mother & baby discharged 24 hours • No evaluation • No therapy later • Observe at least 48 hrs

9 Case Study #1 Case Study #1

 24 hours after discharge (48 hours after  Laboratory tests were ordered: birth): – Urine culture (suprapubic aspiration) – Difficulty nursing and breathing – Blood cultures (from 2 different sites) – Lethargic – CSF culture – Irritable – Gram stains on all fluids  Baby brought to emergency room – Direct Antigen Test (DAT) on CSF and – Fever urine – Hypotension – Ventilator

Case Study #1 Case Study #1

 Laboratory results:  Baby treated successfully with Penicillin – CSF Gram stain  Future pregnancies: • Gram positive cocci in chains – Risk factor category – CSF Culture – Automatic Intrapartum Prophylaxis before • Group B Streptococcus delivery – Direct Antigen Test – Delay discharge of infant for 48 hours • Group B Streptococcus

Case Study #2 : 1995-96 Case Study #2 : 1995-96

 27 year old female  At 39 weeks gestation, vaginal culture reveals growth of normal flora  First pregnancy  6 days later, female is admitted to hospital for  At 32 weeks gestation, urine culture labor induction reveals 10,000 – 50,000 CFU/mL beta-  Vaginal culture is repeated: negative hemolytic streptococci, Group B  7 pound, 4 ounce female is vaginally delivered; apgar score = 9  Ob/Gyn prescribes 250 mg oral  Mother & baby discharged 48 hours later Amoxicillin 2x for 10 days  No complications with GBS

10 Case Study #2 : 1998-99 Case Study #2 : 1998-99

 30 year old female  Ob/Gyn prescribes 250 mg oral  Second pregnancy Amoxicillin 2x for 10 days  Previous GBS carrier; infant not  At 36 weeks gestation, vaginal culture affected repeated; reveals no GBS present  At 13 weeks gestation, vaginal culture  Admission to hospital 30 days later for reveals no GBS present labor induction  At 21 weeks gestation, urine culture reveals 1,000 – 10,000 CFU/mL GBS

Case Study #2 : 1998-99 Case Study #3

 Upon admission (8:00 am):  1938 – IV Penicillin G (5 mu) administered  6 month old male – Four hours later (12:00 pm) :  Diagnosed with streptococcal meningitis • Dosage lowered to 2.5 mu  Grave prognosis – At 3:07 pm: • 8 pound male vaginally delivered; apgar score = 9  7 other babies in with same – Mother & baby discharged 48 hours later diagnosis – No complications with GBS

Case study #3 Case Study #3

 Dr. offered “experimental treatment” “Experimental Treatment”  Mother had to sign consent – Treatment could: • Kill baby • Have no effect • Treat disease Penicillin  Only 1 of 8 mothers signed consent  Treated baby survived; other 7 died

11 Case Study #3 Case Study #3

 Penicillin  Age 21 (after MT school) – Very experimental in 1938  Returned to hospital & met Dr. that – Had not gone to clinical trials / no studies treated him yet  Dr. located patient’s medical chart – Extremely hard to acquire  Cause of patient’s GBS: – Breach baby – Long labor • ROM >18 hours

The Advocate, May 16, 2001 The Advocate, May 16, 2001

 “Child gets $107.8 million malpractice  However, award” – Test was ordered a day later than should – 10 year old male have been – Brain damage due to delayed treatment for – Delay of one day in returning test results bacterial meningitis from lab (sent out) – 1990, New York hospital – Another 24 hours elapsed before patient – Test result showed that mother was was given antibiotics positive for GBS  Jury ruled in favor of patient

Case Study #4 Case Study #4

 Woman delivered baby who developed  So, what happened??? severe GBS disease  Medical records revealed the collection site  Remembered being cultured for GBS & was the cervix results were negative – Suboptimal site  Attorney subpoenaed her medical records – Should be rejected & physician notified  Indicated patient was screened for GBS in  Physician was sued for inappropriate site 35th & 37th week of pregnancy collection  Results were negative  Hospital sued for accepting & processing

the specimen Medical Laboratory Observer, April 1, 2012

12 Concerns with Prophylaxis Concerns with Prophylaxis

 Adverse effects from antibiotics  Antimicrobial-resistant pathogens – Mild allergic reactions – 27% of pregnant women in U.S. receive – Anaphylaxis antibiotics during labor & delivery – Consequences for newborn treatment – 15% of GBS isolates resistant to Clindamycin (observe for 48 hours) or Erythromycin (no longer recommended w/o susceptibility testing) – Ampicillin-resistant Escherichia coli is increasing as cause of neonatal sepsis due to GBS-associated IAP

Possible Solutions Possible Solutions

 Vaginal Disinfectants  Vaccine development – Less invasive approach – No licensed vaccine currently available – Chlorhexidine investigated in randomised – Clinical trials are in progress trial in Sweden • Healthy, nonpregnant adults • Have shown vaccines to be well tolerated and – Less effective than antibiotic prophylaxis immunogenic – Does not lead to an increase in resistant pathogens – Clinical trials have found no protection against early-onset GBS disease - 2014

Concerns about Vaccination Vaccination During Pregnancy

 Vaccination during pregnancy  Most women reluctant to accept vaccine  Optimal timing of vaccination during pregnancy  Proposed target group: include non- – Warned to avoid smoking, alcohol & drugs pregnant women and even adolescent – Concerned about adverse effects of girls vaccine on developing fetus  Shift in serotypes of strains causing GBS disease

13 Timing of Vaccination Proposed Target Group

 Timing is crucial to minimize potential  Addition of GBS vaccine to adolescent harm to fetus while allowing adequate series (when booster doses are time for GBS antibodies to be produced administered) – Duration of protection is unknown  Health care professionals agree that rd – Need to protect women over all of their early in 3 trimester is most appropriate reproductive years time to vaccinate (low risk to fetus; – Many booster doses may be necessary and enough time to produce antibodies & complicate vaccination programs cross placenta) – Many countries do not immunize at this age

Other Suggestions: Natural Other Suggestions: Natural Remedies Remedies

 Boost competitive & healthy bacteria  No studies regarding the effectiveness – Probiotics (yogurt & aged cheeses) of these remedies  Boost the immune system  However, many women have – Avoid sugars & refined carbohydrates experienced a reversal from positive to – Increase vitamin C and D negative cultures for GBS after following – Increase proteins & vegetables in diet one or more of these remedies  Kill the bacteria  Many websites with suggestions of – Garlic, tea tree oil, colloidal silver herbal remedies to prevent GBS

Organizations Endorsing the 2010 GBS Guidelines

 American College of Obstetricians & Gynecologists 2010 Revised Guidelines  American Academy of Pediatrics  American College of Nurse-Midwives MMWR, Vol. 59  American Academy of Family (RR-10) Nov. 19, 2010 Physicians  American Society for Microbiology

14 Major Differences in New Minor Differences in New Guidelines Guidelines

 Expanded options for lab detection of  Recommendations for IAP agents to GBS, including use of pigmented media promote the most appropriate antibiotic & PCR assays for penicillin-allergic women  Revised colony count threshold for labs (clindamycin & erythromycin) to report GBS in urine of pregnant  Penicillin dosing changed to facilitate women the implementation in facilities with different pre-packaged penicillin products

What Can You Do to Help? Educational Methods

 Make sure your OB, Peds, and  Communication between Ob/Gyn and Microbiology colleagues keep up with patient the new guidelines  Public Awareness  Ensure your lab is using selective broth – Literature (brochures, advertising, posters) medium – Videos  Plan steps needed for implementation in – Web Sites your facility

Brochures Posters

Pre-natal Facilities

15 Posters Web Sites

Labor &  CDC's GBS Internet page Delivery – http://www.cdc.gov/groupbstrep

 GBS Association home page – http://www.groupbstrep.org Non-profit organization formed in June, 1990 by parents whose babies died from GBS

Podcasts e-cards

Pinterest: July is GBS Prevent Group B Strep App Awareness Month

16 Strepelle Home to Lab Test Kit

 Only available in United Kingdom  Two swabs collected by pregnant female (vaginal & rectal)  Swabs mailed to lab in transport gel  Results in 3 days  Cost $39.99

Key GBS Resources

 MMWR 2010;59 (No. RR-10):1-36  CDC's GBS Internet page – http://www.cdc.gov/groupbstrep  GBS Association home page – http://www.groupbstrep.org

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