Alexandria Egypt Sepsis 02-04-09

2nd International Neonatology Conference April 2 - 4, 2009 Alexandria, Egypt

Neonatal septicemia: Current concepts and the role of neonatal host defense

Prof. Christian P. Speer, MD, FRCPE Director and Chairman University Children’s Hospital Würzburg, Germany

Neonatal Sepsis

• Incidence • Meningitis • Case fatality

1- 4 Newborns / 1000 LB / Year 5 - 25 % ~ 25 % (5 - 60%)

Neonatal Sepsis Mortality • 1.6 Million Deaths / Year1 • Infections as cause of death in > 50 % of extremely LBW infants on autopsy2 Morbidity • Association between chorioamnionitis and cerebral palsy in mature infants (odds ratio 9.3, CI 2.7-31)3 • Qualitative MRI in extremely LBW infants: Association between non-cystic white mater injury (oligodendroglial specific injury) and perinatal infection (maternal fever, proven neonatal sepsis at delivery4) • Adverse neurodevelopmental outcome in preterm infants with postnatal sepsis or NEC is mediated by white matter abnormalities on MRI 5 Vergnano et al, Arch Dis Child Fetal Neonatal Ed 2006; 2 Barton et al, Pediatrics 1999; 3 Grether and Nelson, JAMA, 1997; 4 Inder et al, J Pediatr 2003; 5 Shaw et al, J Pediatr 2008 1

Descending infection

Ascending infection

Risk Factors of Early Onset Sepsis • Prolonged rupture of membranes >18 hours • Preterm premature rupture of membranes • Maternal amnionitis • Fever, bacteremia of the mother • Prematurity

Bacterial Colonization of Pregnant Women and Newborns in European Countries Bacteria Rate

Rectal-Vaginal Colonization Attack Colonization of the Newborn

GBS* 8 - 36 % 40 - 70 % ~ 1:100 E. coli 32 - 50 % 30 - 70 % ~ 1:200 • Women colonized with GBS* prenatally have a 25 fold higher risk of delivering a baby with early onset GBS compared with non-colonized women Barcaite et al Acta Obstet Gynecol 2008 (Review)

*GBS: Group B-Streptococci

Route of Infection Mikroorganismen

Spectrum of GBS Infection ● Pneumonia

35 - 55 %

● Sepsis

25 - 40 %

● Meningitis

4 - 10 %

● ~ 75 % of cases with GBS infection are early onset (within the first days of life) ● Most affected infants become ill within the first 24 hours

Tumbaga, Philip, NeoReviews 2003

Impact and risk factors for early-onset group B streptococcal disease: analysis of a national, populationbased cohost in Sweden 1997-2001, 435 070 live births Tentative risk factor

Verified sepsis n=174

Gestational age (completed weeks)

OR

95% CI

< 28 28-31 32-34 35-36 37-41 ≥ 42

22 34 11 5 3.5 1.9

8.5-57 18-62 6-21 2- 9 2-6.5 1-3.7

S Hakansson, K Källén, BJ0G 2006

Case Fatality Rates of Neonates with Early-Onset GBS-Sepsis in the United Sates, 1993 – 1998 n = 1584

Gestational Age

Case Fatality

< 33 wk

30 %

34 – 36 wk

10 %

> 37 wk Schrag SJ et al, NEJM 2000

2%

Case fatality rates for E. coli sepsis (Australasia, 1992 – 2001)

Birthweight

Case fatality rates

<1500g

33/66 (50%)

>1500g

2/30 (7%)

Daley AF et al. Pediatr Infect Dis J 2004

Predominant Microorganisms Responsible for Septicemia 60 50

(%)

40 30 20 10 0 USA 2000 GBS

Germany Spain 1997 2000

Israel 1997

coag.-neg. Staphylococci

Banerjea, Speer, Pädiat Prax, 2002

Nigeria Pakistan Panama 1999 2000 1994

Klebsiella Species

E.coli

Causes of serious bacterial infections in babies aged 0-3 days in hospitals of developing countries (1990-2004) 70 Proportion (%)

60 50 40 30 20 10 0

Africa (n=110)

Middle east (n=27)

GBS

South Southeast Asia Asia (n=239) (n=91)

E.coli

S aureus

Latin Am/ Caribbean (n=41)

All developing regions (n=508)

Others

Klebsiella spp, Pseudomonas spp, Acinetobacter spp,and other gram negative rods Zaudu AKM et al. Lancet 2005

Neonatal Infections in Asia

Iran, Thailand, China, Malaysia, Hong Kong, India, Australia

Organisms causing early-onset sepsis Organism

n (%)

Group B streptococcus Coagulase-negative staphylococcus Escherichia coli Staphylococcucs aureus

18 (38) 8 (17) 6 (13) 2 (4)

Other Gram-negative bacilli Other Gram-positive cocci

11 (23) 2 (4)

Total

47 (100)

Tiskumara, Arch Dis Child Fetal Neonatal Ed 2009

Day of first positive culture of coagulase negative staphylococci from blood or cerbrospinal fluid

Number of infected babies

100 90 80 70 60 50 40 30 20 10 0

3

5

7

9

11

13

15

17

19

21

Day of first positive culture Isaacs et al, Arch Dis Child Fetal Neonatal Ed 2003

23

25

27

29

Preterm infant/ Newborn

Cellular and humoral defense Innate immunity

LA: cell wall constituent of Gram-positive bacteria

Microorganisms

Factors of virulence - adherence - capsules - biofilm - endotoxin (LPS) - lipoteichoic acid (LA)

Neutrophils (mm³)

Total Number of Neutrophils

25000 20000 15000 10000 5000 12

24

36

hours

48

60 5

10

15

20

days

25

80 Postnatal Age

Granulopoesis in Newborns and Adults Newborns

Adults CFU - GM (%) 10 100 Proliferation (%) 80 25 Bone marrow reserve (%) 25 100 Manroe et al., J Pediatr 1977 Christensen et al, 1986, 1988; Cairo et al, 1990 Banerjea, Speer, Semin, Neonatol, 2002 Neutrophil release

Capillary LFA-1

CR-3

LFA-1

Shedding

CR-3 L-selectin Receptor

s-Lex

PSGL-1

P-selectin E-selectin ICAM-1

ICAM-2

Tissue Contact

Rolling

Urlichs, Speer NeoReviews 2004

Firm Adhesion

Diapedesis

Adherence and Receptor Expression by Neutrophils From Pretern and Term Infants Compared With Cells From Adults Preterm

Term

General adherence "Rolling" L-selectin (CD62L) expression L-selectin shedding

CR3 (CD11b/CD18) - surface expression

N

N

N

N

- upregulation LFA-1 (CD11a/CD18) expression

N = normal;

= decreased

Urlichs, Speer NeoReviews 2004

Circulation

Adherence

Apoptosis

Chemiluminescence

O2 H2O2 OH

Killing

Degranulation Microorganism Phagocytosis

Deformability Chemotaxis

Capillary

Tissue

( mg per 100 ml )

Serum-γ G Glubolin

2000 1000 800 600 400 300 200 100 50

20

25

30

35

40

Estimated Gestation (weeks) Serum γ G-globulin levels on logarithmic scale plotted against gestational age on linear scale Hobbs, Davis, Lancet 1967

specific IgG

C 3b opsonised bacterium

Fc-receptor

C3b-receptor

cell membrane Lysosome

Phagocytosis

Recognition of cell wall components of Gram-positive and Gram-negative bacteria by Toll-like recepors TLR2 and TLR4 Peptidoglycans Lipopeptides

1 CD

TLR2

4

TLR4

Mal MyD88

LPS Lipoteichoicacid

Mal TRAF-6

MyD88 TRIF

Cell

NF-kB

Transcription of inflammatory cytokines

Activation of Immune Cells by LPS and by GBS Cell Wall Constituents LPS

GBS (cell wall, soluble factors)

Toll-like receptors Concentrations

TNF-α

low

● adhesive molecules ● activation of neutrophils, monocytes , macrophages

high

● massive release of proinflammatory cytokines ● activation of clotting- and complement system

very high

● hypotension ● myocardial depression ● DIC

Berner et al, Pediatr Res 2001, Henneke et al, J Immunol 2002

Different GBS-Strains and Platelet Aggregation GBS-strain (GS130903); colonization of skin

Platelet Aggregation

-20 0

Platelets (no bacteria)

20 40 60 80

GBSreference strain (ATCC13813)

100 0

6

Siauw, Speer; Thromb Hemost, 2006

GBS-strain (SJ250903); Neonatal Sepsis 12

18

minutes

24

30

Partial Systemic Immunodeficiencies of Preterm and Term Infants ● IgG-concentrations in preterm infants ● Specific antibodies ● Complement activity in preterm infants ● Opsonin-dependent phagocytosis ● Bone marrow reserves ● Phagocyte functions - adherence - chemotaxis

● Myd88 expression in neonatal monocytes following TLR2 and TLR4 stimulation ● Production of IFN-γ by neonatal lymphocytes ● Activation of macrophages

Immune Therapies • Exchange transfusion

No benefit

• Granulocyte transfusion

Insufficient evidence 1

• G-CSF, GM-CSF

Insufficient evidence 2

• Immunoglobulins

Insufficient evidence 3

Mohan, Brocklehurst, Cochrane Database 2003 Cars et al, Cochrane Database 2003 3 Ohlsson, Lacy, Cochrane Database Syst Rev 2004; 1 2

Prevention of Sepsis by Immunoglobulins Randomized contr. double-blinded multicenter trial: Preterm infants 500 - 1500 g (n = 2416) Sepsis

Nosocomial Sepsis

Mortality

IgG

16 %

17 %

11 %

Placebo

17 %

19 %

11 %

Fanaroff et al, NEJM, 1996

Meta-Analysis of Intravenous Immunoglobulins (IVIG) • Prophylaxis1

- 3 % reduction in sepsis (p < 0.02) - No reduction in mortality or other severe outcomes (IVH, NEC etc.) • Therapeutic administration2 - inconsistent effects • Conclusion: There is currently insufficient evidence to support prophylactic or therapeutic IVIG to prevent mortality in infants with neonatal sepsis3 1 Ohlsson, Lacy, Cochrane Database Syst Rev 2004; 2 Ohlsson, Lacy, Cochrane Database Syst Rev 2004; 3 Suri, Cairo, Curr Opin Pediatr 2003

New Guidelines for GBS Prevention -American Academy of Pediatrics and American College of Obstetricians and Gynecologists -

● Universal screening of all pregnant women at 35 to 37 weeks’ gestational age is the proposed standard of care. It prevents more cases of early onset disease than the risk-based approach. ● Intrapartum prophylaxis has decreased the incidence of early-onset GBS sepsis by 70 %. ● Penicillin G remains the drug of choice for intrapartum prophylaxis ● For patients who are allergic to penicillin but do not have a history of anaphylaxis,cefazolin is the preferred choice Schrag et al, NEJM 2002; Tumbage, Philip, NeoReviews 2003

Cases per 1000 Live Births

Rate of early-onset and late-onset invasive group B streptococcal disease in infants, by year United States, 1996-2004 1.0 0.9

Prophylaxis protocol implemented

0.8

Early-onset disease Late-onset disease

0.7 0.6 0.5 0.4 0.3 0.2 1996 1997 1998 1999 2000

Year

2001 2002 2003 2004

Timing of Intrapartum Ampicillin Administration and Rate of Vertical Transmission Time Between Ampicillin Administration and Delivery

Number of Group B Streptococci Carriers

Number of Colonized Newborns (%)

<1h

24

11 (46)

1 to 2 h

21

6 (28)

> 2 to 4 h

70

2 (2.9)

>4h

86

1 (1.2)

253

120 (47)

Control group (no ampicillin) De Gueto et al, Obstet Gynecol, 1998

Intrapartum Antibiotics and Consequences on Newborn Treatment ● Pediatric recommendations suggest a 48-hour observation period for infants whose mothers received antibiotics ● With the exception of maternal chorioamnionitis routine use of antibiotics in infants whose mothers have received adequate treatment is not indicated ● Postnatal penicillin prophylaxis in infants has been associated with an increased mortality and is not recommended Tumbaga, Philip, NeoReviews 2003

Exposure

Gestation > 37 weeks PROM < 12 hours Less virulent GBS Low inoculum

Gestation < 37 weeks Chorioamnionitis PROM > 18 hours Virulent GBS High inoculum

Health

Disease

Maternal Antibody to Capsule

Histologic Chorioamnionitis Histological chorioamnionitis %

70 60

n= 261

n= 139

50

n= 200 n= 164 n= 236

40 30

n= 284

n= 375

n= 380

n= 539

20

n= 580

n= 770

10 0

20-24 25

26 27 28 29 30 31 32 Gestational Age (completed weeks)

Lahra and Jeffrey, AJOBGYN, 190:147, 2004

33

34

Frequency of a positive amniotic fluid (AF) culture and intraamniotic inflammation 80 60 % 40 20 0

20-27

27-30 30-33 Gestational age (weeks)

intra-amniotic inflammation (P< .001) Shim et al, Am J Obstet Gynecol, 2004

33-35

positive AF culture (P< .05)

Detection of bacteria in placental tissues obtained from extremely low gestational age neonates Study design: A sample of the chorionic parenchyma from neonates delivered between 23 – 27 weeks was cultured and tested by PCR , n = 1365 Results: Culture positive 68% of vaginal deliveries 41% of caesarean sections 30% had only aerobic bacteria 21% had only anaerobic bacteria 9% had Mycoplasma / Ureaplasma Conclusion: Approximately half of second – trimester placentas harbour organisms within the chorionic plate Onderdonk et al AJ0G 2008

Intrauterine Cytokine Exposure TNFα IL-1 IL-8

Systemic Fetal Inflammatory Response

Elevated IL-6 concentrations in umbilical cord blood Yoon et al, Am J Obstet Gynecol, 1999

The Alabama Preterm Birth Study: Umbilical cord blood Ureaplasma urealyticum and Mycoplasma hominis cultures in very preterm newborn infants Study 351 mother / infant dyads with deliveries between 23 and 32 weeks’ gestational age Results U. urealyticum an for M. hominis were present in 23% of cord blood cultures Intrauterine infection and inflammation were more common among infants with positive U. urealyticum and M. hominis cultures Infants with positive cord blood U. urealyticum and M. hominis cultures were more likely to have neonatal systemic inflammatory response syndrome (SIRS) and probably bronchopulmonary dysplasia (BPD). Goldenberg et al, AJOG 2008

Twenty percent of very preterm neonates (23-32 weeks of gestation) are born with bacteremia caused by genital Mycoplasmas

Romero, Garite, AJOG, 2008

Colony forming units for Ureaplasma urealyticum at delivery and postnatal tracheal aspirates in premature baboons 10.000.000

CFU`s

1.000.000 100.000 10.000 1.000 100 10 1

AF 24 hr (amniotic fluid)

72 hr

144 hr

240 hr

336 hr

Animals with negative culture at 14 days of postnatal age (Uu -), n=5 Animals with persistently positive cultures (Uu+), n=4

Yoder, Coalson et al, Pediatr Res 2004

Effects of antenatal colonization with Ureaplasma urealyticum on pulmonary disease in the immature baboon

Uninfected animals ventilated for 14 days

Yoder, Coalson et al, Pediatr Res 2004

Uu - negative animals at 14 days of age

Uu - positive animals at 14 days of age

Premature Rupture of Membranes

Maternal Amnionitis

Increased risk for VLBW infants to develop - Neonatal sepsis

1, 2, 3, 4, 5,6

- Bronchopulmonary dysplasia

1-7

- Severe intracerebral hemmorhage (ICH) 1, 3, 5 - Periventricular leukomalacia (PVL) 1, 3, 5 Neurodevelopmental and growth impairment among extremely LBWI with neonatal infection7 Alexander et al, Obst Gynecol 1998; 2 Dexter et al, Obstet Gynecol 1999; 3 Morales, Obstet Gynecol 1987 4 Beazley, Am J Obstet Gynecol 1998; 5 Ramsey et al, Am J Obstet Gynecol 2005; 6 Constantine et al, Am J Obst Gynecol 2007; 7 Stoll et al JAMA 2004 1

Clinical Signs of Sepsis •Respiratory distress • Thermal instability - hyperthermia - hypothermia • Pallor, peripheral vasoconstriction • Abdominal distension, vomiting, poor feeding • Irritability • Lethargy • Apnoea

Early Identification and Alarm Signs of Sepsis • Obstetrical risk factors • Clinical symptoms • Markers of inflammation - leucocytes - total number of neutrophils (T) - total number of immature neutrophils (I) - I/T-ratio - CRP - IL-6 - others • Identification of microorganisms; blood culture 0.5ml; frequently an insufficient amount of blood is drawn

Microbial invasion Recruitment and activation of neutrophilis and macrophages Mediator release by macrophages TNF-α IL-1 IL-6 Organ Reaction Liver: akute Phase-Reaction CRP

Symptomatik

Time (hours)

Plasma levels (Arbittray Units)

LPS

Cytokine profile kinetics after TNF experimental endotoxemia IL-1 IL-6

0

1 2 3 Hours after challenge

CRP

4

5

Abbas AK: Cell Mol Immunol, 1994

Diagnostic Tests for “Early Identification” or “Ruling out” of Sepsis Conclusion • No single individual test or combination of tests has a positive predictive accuracy of sepsis more than 40 % • Serial CRP determinations or sepsis screens (WBC, neutrophil counts, CRP, IL-6) have an extremely high negative predictive accuracy of sepsis (> 99 %) and can be helpful in ruling out infection Polin, J Pediatr 2003

Empiric use of ampicillin and cefotaxime, compared with ampicillin and gentamicin, for neonates at risk for sepsis is associated with an increased risk of neonatal death. Clark RH, Bloom BT, Spitzer AR, Gerstmann DR

BACKGROUND: Use of cephalosporins among premature neonates increased the risk of subsequent fungal sepsis. As a result, it is recommended that ampicillin and gentamicin be used as empiric coverage for early-onset neonatal sepsis while culture results are awaited. RESULTS: There were 128,914 neonates selected as the study cohort; 24,111 were treated concurrently with ampicillin and cefotaxime and 104,803 were treated concurrently with ampicillin and gentamicin. Logistic modeling showed that neonates treated with ampicillin/cefotaxime were more likely to die : adjusted odds ratio: 1.5; 95% confidence interval: 1.4-1.7 Pediatrics, 2006;117:67-74