Fever in the NeonateFever in the Neonate

June 2003June 2003

QODQOD

A 2 week old infant who was born at term A 2 week old infant who was born at term has fever, poor feeding, lethargy, and a has fever, poor feeding, lethargy, and a bulging fontanelle. The CSF is cloudy and bulging fontanelle. The CSF is cloudy and contains 2,000 WBCs/mmcontains 2,000 WBCs/mm33

The organism MOST likely to be causing The organism MOST likely to be causing this infant’s problem is:this infant’s problem is:

A.A. GBBSGBBSB.B. H. fluH. fluC.C. ListeriaListeriaD.D. NeisseriaNeisseriaE.E. Strep pneumo Strep pneumo

Learning ObjectivesLearning Objectives

Define feverDefine fever Know which age group with fever is of Know which age group with fever is of

highest concernhighest concern Know the mortality of neonatal sepsisKnow the mortality of neonatal sepsis Be able to explain the “rule out sepsis” Be able to explain the “rule out sepsis”

work upwork up Identify the most common Identify the most common

troublesome bacteriatroublesome bacteria

What is a Fever?What is a Fever?

Fever Fever – Temperature > or = 38.0C (100.4F)Temperature > or = 38.0C (100.4F)

How is it taken?How is it taken?– RectalRectal

Until old enough to keep thermometer under Until old enough to keep thermometer under the tonguethe tongue

– Tympanic and axillary temps Tympanic and axillary temps may miss 20-30% of feversmay miss 20-30% of fevers

Does time of fever recognition matter?Does time of fever recognition matter?– If fever discovered at home, but not If fever discovered at home, but not

present in office or ER, then MUST act on present in office or ER, then MUST act on historyhistory

Who is a Neonate?Who is a Neonate?

Neonate = <30 days oldNeonate = <30 days old In this context of Neonatal Fever In this context of Neonatal Fever

(Fever of Neonates and Young (Fever of Neonates and Young Infants?)Infants?)– Birth – 2 monthsBirth – 2 months– Debate on 2-3 months oldDebate on 2-3 months old

Why Worry about Why Worry about these Infants?these Infants? Most appear WELLMost appear WELL

No test is 100% sensitive/specific for No test is 100% sensitive/specific for serious bacterial infection (SBI)serious bacterial infection (SBI)

Can have rapid decline in face of SBICan have rapid decline in face of SBI

Fever may be the only indicator of Fever may be the only indicator of SBISBI

SBI =

bacterial meningitis, bacteremia, septic arthritis, osteomyelitis, UTI, bacterial enteritis, pneumonia

EpidemiologyEpidemiology

Incidence of SBI in febrile infantsIncidence of SBI in febrile infants– <1 month old – 13%<1 month old – 13%– 1-2 months old – 10%1-2 months old – 10%

So… younger age means higher So… younger age means higher riskrisk– 0-1mo>1-3mo>3-36mo0-1mo>1-3mo>3-36mo

Highly morbid conditionHighly morbid condition– Mortality of neonatal sepsis is 10-40% Mortality of neonatal sepsis is 10-40%

with significant morbiditywith significant morbidity

Why the Higher Risk?Why the Higher Risk?

Lower level of Lower level of immunocompetenceimmunocompetence– Decreased opsonin activityDecreased opsonin activity– Decreased macrophage functionDecreased macrophage function– Decreased neutrophil activityDecreased neutrophil activity

Poor IgG response to Poor IgG response to encapsulated bacteriaencapsulated bacteria– Until >24 months oldUntil >24 months old

So…What Do We Do?So…What Do We Do?

An An excellentexcellent HISTORY HISTORY– Especially with well-appearing infant, Especially with well-appearing infant,

diagnosis and level of concern likely diagnosis and level of concern likely determined by historydetermined by history

– Birth hx, PNC, recent Abx use, perinatal Birth hx, PNC, recent Abx use, perinatal exposures, h/o hyperbilirubinemiaexposures, h/o hyperbilirubinemia

Problems with the historyProblems with the history– Inconsistent presentation amongst febrile Inconsistent presentation amongst febrile

infantsinfants– Several clinical parameters have been Several clinical parameters have been

studied as predictors of SBIstudied as predictors of SBI None have been found to be 100% sensitive and None have been found to be 100% sensitive and

specific for infants <2months oldspecific for infants <2months old

The Physical ExamThe Physical Exam

Again….Again….– Most are well-appearingMost are well-appearing

2 large studies:2 large studies:– 747 febrile 1-2months old infants – 747 febrile 1-2months old infants –

66% appeared well to the MD despite 66% appeared well to the MD despite having SBIhaving SBI

– Similar study of 1-3 months old Similar study of 1-3 months old infants – those with SBI could not be infants – those with SBI could not be weeded out from those without by weeded out from those without by appearance aloneappearance alone

Well-Appearance DOES NOT rule out SBI

Deciding on Deciding on ManagementManagement

What does the literature say?What does the literature say?– Rochester criteriaRochester criteria– Philadelphia criteriaPhiladelphia criteria– Boston criteriaBoston criteria

More widely acceptedRochester CriteriaNo source for feverPreviously healthy

Full termNo prior or current Abx

NontoxicWBC 5,000-15,000

<1,500 bandsUA <10 WBC/HPF

Stool <5 WBC/HPF (if diarrhea)

Philadelphia CriteriaObservation Score

WBC<15,000Band:Seg <0.2

UA <10 WBC/HPFCSF analysis <8 WBC

Normal CXR

Boston CriteriaWBC<20,000

UA <10 WBC/HPFCSF analysis < 10WBC

Normal CXRAll criteria missed diagnosis of SBIin <1 month olds

Well-Established Well-Established ManagementManagement

< 1 month old< 1 month old– Automatic “rule out sepsis” work upAutomatic “rule out sepsis” work up

CBC with differentialCBC with differential Blood cultureBlood culture Urine cultureUrine culture

– Via straight cath or suprapubic tapVia straight cath or suprapubic tap CSF analysis and cultureCSF analysis and culture

– Glucose, protein, gram stain, cell count, and cultureGlucose, protein, gram stain, cell count, and culture– If clinically indicatedIf clinically indicated

CXRCXR NP aspirateNP aspirate

– RSV/ Influenza A screen as indicatedRSV/ Influenza A screen as indicated– AdmitAdmit– Empiric antibiotics until cultures negative for 48hrsEmpiric antibiotics until cultures negative for 48hrs

1-3 Month Olds – 1-3 Month Olds – Tougher DecisionTougher Decision

1-2 months old – usual practice1-2 months old – usual practice– Blood culture, CBC with diffBlood culture, CBC with diff– CSF evaluation CSF evaluation – Urine culture Urine culture – CXR CXR

clinically indicatedclinically indicated– NP aspirate NP aspirate

RSV/ Influenza A screen as indicatedRSV/ Influenza A screen as indicated– Hospitalize, treat with empiric antibiotics, and Hospitalize, treat with empiric antibiotics, and

observe for 48 hoursobserve for 48 hours 2-3 months old2-3 months old

– ““gray-zone”gray-zone”– No consensus on managementNo consensus on management

Bad BugsBad Bugs

GBBS, GBBS, GBBS, GBBS, GBBS! GBBS! (Streptococcus (Streptococcus agalactiae)agalactiae)

E.ColiE.Coli ListeriaListeria After d/c home, After d/c home,

thinkthink– Strep pneumoStrep pneumo– H. fluH. flu

GBBS and E. coli account for 50-70% of all neonatal infections

Antibiotic RegimenAntibiotic Regimen

Before discharge from Nursery or NICUBefore discharge from Nursery or NICU– Ampicillin and gentamicinAmpicillin and gentamicin

No H. flu coverageNo H. flu coverage After discharge homeAfter discharge home

– Ampicillin Ampicillin andand– Cefotaxime if <3moCefotaxime if <3mo– Ceftriaxone if >3mo Ceftriaxone if >3mo

Risk of ceftriaxone causing bilirubin Risk of ceftriaxone causing bilirubin displacement and theoretical risk of biliary displacement and theoretical risk of biliary sludging in <3month oldsludging in <3month old

After 6-9 weeks old, ampicillin for After 6-9 weeks old, ampicillin for listeria coverage is not necessarylisteria coverage is not necessary

The Daily The Daily QUIZQUIZ Continues!!Continues!!

Define FeverDefine Fever

38.0C or 100.4F or higher38.0C or 100.4F or higher Why not tympanic or axillary Why not tympanic or axillary

temps?temps?

Miss 20-30% of feversMiss 20-30% of fevers Who is at greatest risk of SBI?Who is at greatest risk of SBI?

0-1mo>1-2mo>3-36month0-1mo>1-2mo>3-36month

Oh, No! There’s More!!Oh, No! There’s More!!

Describe the “rule out sepsis” work upDescribe the “rule out sepsis” work up

CBC with diffCBC with diff

Blood cultureBlood culture

Urine cultureUrine culture

CSF analysis and cultureCSF analysis and culture Labs are drawn – now what?Labs are drawn – now what?

AdmitAdmit

Empiric antibioticsEmpiric antibiotics

Name the “Bad Bugs”Name the “Bad Bugs”

GBBS! GBBS! GBBS!GBBS! GBBS! GBBS!

E.coliE.coli

ListeriaListeria

Strep pneumoStrep pneumo

H. fluH. flu

Choose your antibioticsChoose your antibiotics In the nursery?In the nursery?

Ampicillin and gentamicinAmpicillin and gentamicin 6 week old at home?6 week old at home?

Ampiciliin and cefotaximeAmpiciliin and cefotaxime 9 week old at home?9 week old at home?

Ampicillin (?) and ceftriaxoneAmpicillin (?) and ceftriaxone

QODQOD

A 2 week old infant who was born at term A 2 week old infant who was born at term has fever, poor feeding, lethargy, and a has fever, poor feeding, lethargy, and a bulging fontanelle. The CSF is cloudy and bulging fontanelle. The CSF is cloudy and contains 2,000 WBCs/mmcontains 2,000 WBCs/mm33

The organism MOST likely to be causing The organism MOST likely to be causing this infant’s problem is:this infant’s problem is:

A.A. GBBSGBBSB.B. H. fluH. fluC.C. ListeriaListeriaD.D. NeisseriaNeisseriaE.E. Strep pneumo Strep pneumo

GBBS

Higher risk in older infants

Accounts for 5% of neonatal infections

GBBS and E. coli account for 50-70%% of all neonatal infections

Summer is Finally Here!Enjoy!!