The Febrile Child:Treat ‘em or Street ‘em

David Chaulk

Pediatric EM Fellow

January 2004

Overview

• Cases• Temperature

Measurement• Who Cares?• Schools of Thought• Scoring Systems• Empiric Therapy

• Changes in Prevalence & Changes in Management

• Recognizable Illnesses• CPS Guidelines• Cases Revisited

Case 1• A 3 week old male infant is brought to your ED with a 2 day

history of fever. He was born by uncomplicated vaginal delivery at 37 weeks gestation following a normal pregnancy. At his two week check-up he was noted to be gaining weight appropriately. His vital signs are: T 38.9C (R), HR 140, RR 40, and BP 90/60. He is sleepy but easily rousable. Physical exam is normal apart from a slightly dull left tympanic membrane. His peripheral WBC is 16,000, his UA shows 3 WBC/hpf. BC and UC are sent. Your management at this point would consist of:

a. Discharge on antipyretics with close follow-upb. Discharge on oral amoxicillin with close follow-upc. LP and admission for parenteral antibioticsd. CXR to r/o pneumoniae. Stool for analysis and culture, and outpatient follow-up

Case 2

• A 7 week old girl is referred in to ED for evaluation of a rectal temperature of 39.2C. Her PE is normal. Her UA is negative, her WBC is 9,000 (70% neuts, 28% lymphs, 2% bands). BC, UC are sent. Acceptable management options for this child would include any one of the following except:

a. IM ceftriaxone in the EDb. Admission to the hospital for IV antibioticsc. Discharge with follow-up in 24 hoursd. Admission to the hospital for observatione. Discharge on amoxicillin

• Any other investigations?

Case 3

• A 19 month old boy comes to the ED with a 3 day history of fever. He appears well but his tympanic T is 39.8C. His chest is clear, his abdomen is soft, and he is circumcised. No source can be found for his fever. A CBC reveals a WBC of 8200 (60% neuts, 27% bands). BC’s are sent.

Appropriate management at this point will be to:

a. Obtain a urine sampleb. Administer IM ceftriaxonec. Perform an LPd. Obtain a CXRe. Discharge on antipyretics

Temperature Measurement

Source Fever Problem

Rectal > 38 Invasive, takes time

Oral 0.5 lower Technique dependent

Axillary 1.0 lower ? Reliability

? variability

Tympanic 0.5 lower Technique dependent

• Rectal is gold standard based on study from 1937!• Controversial! Tympanic very accurate or very

inaccurate• Lanham 1999…tympanic misses too many febrile

children• Shinozaki, 1998…rectal inaccurate because of poor

blood supply to rectum, T is slow to change• Physiologically, T controlled by hypothalamus• Hypothalamus and Tympanic Membrane have same

blood supply (common carotid)

Temperature Measurement

Age Recommended technique Birth to 2 years

1. Rectal (definitive)2. Axillary (screening)

Over 2 years to 5 years 1. Rectal

2. Tympanic3. Axillary

Older than 5 years1. Oral2. Tympanic3. Axillary

Temperature MeasurementCPS Guidelines

Who cares?

• 65% of children 0-2 will visit a physician for a febrile illness– 10-20% of PED visits, 20-30% ped office visits

• 50% are fever without source

• Most represent self-limited illness

• Small precentage with Serious Bacterial Illness…but who?

A few Definitions…

• Fever without Source– “…An acute febrile illness in which the

etiology of the fever is not apparent after a careful history and physical examination.”

• Baraff et al, Pediatrics 1993; 92:1-12

• Fever of Unknown Origin1. Fever > 2 to 3 weeks2. Absence of localizing signs3. Failure of simple diagnostic efforts

• Occult Bacteremia– “…a positive blood culture in the setting of well appearance

and without focus (e.g. no pneumonia), BUT may be in the presence of URTI, otitis media, diarrhea, or wheezing”

– Fleisher et al, J Pediatrics 1994

• Serious Bacterial Infections– “…SBI include meningitis, sepsis, bone and joint

infections, urinary tract infections, pneumonia and enteritis”– Baraff et al, Pediatrics 1993; 92:1-12

A few Definitions…

Occult Bacteremia

• Strep pneumo. >85%• N.meningitidis 3-5%• Others

– GAS– Staph aureus– Salmonella spp– HiB

• Now rare, previously was ~10%

Bacteremia

• < 2 mos, T > 38 incidence is 2-3%Avner and Baker, Emerg Med Clin NA 2002;20(1)

• 3-36 mos, T < 39 incidence is <2%Klein, Ped Inf Dis J 2002;21(6):584-8

• 2002 data, ie. Post HiB era

Untreated Bacteremia Outcomes

• Persitent fever 56%

• Persistent bacteremia 21%

• Meningitis 9%– S.pneumo 6%– HiB 26% (no longer seen)

Scoring Systems

• Demographic and Clinical Parameters– Age, temperature, clinical appearance

• Lab Screens:– CBC, ESR, U/A

• Initially very promising…ultimately not so “hot”

Scoring Systems

• Can we identify high risk kids?– Yale Observational Score– 611 children, 192 bacteremic– Median score was the same for both groups– A high score was a good marker

• Specificity and NPV ~97%• Sensitivity and PPV ~5%

– Not great screening tool (screens should be sensitive)

Scoring Systems

• Can we identify low risk kids?• Three main scoring systems

– Philadelphia, Rochester and Boston Criteria– All are similar but there are differences

• Main risk factors identified– Age (3 groups. 0-28d, 28-90d, 3-36m)– Temperature T > 40.5 8-25% with OB– Petechiae – 15-20% SBI– WBC >15,000, bands>1000 – 5 fold in OB– Toxic appearance

Lethargy/irritabilty Poor eye contactPoor perfusion Hypo/hyperventilationCyanosis

Philadelphia Rochester Boston

Age 1-2 months 0-2 months 1-3 months

Temperature 38.2C 38.0C 38.0C

History Not specified Term infant

Previously well

No recent vacc /abx

Not dehydrated

Physical examination Well-appearing (IOS < 10)

Well-appearing Well-appearing

Laboratory parameters (defines lower-risk patients)

Wbc < 15,000

BNR < 0.2

UA < 10 WBC/hpf

Urine gram stain –ve

CSF <8 WBC

CSF gm stain –ve

CXR clear

Stool: no blood, few or

no WBC’s on smear

WBC > 5,000; < 15,000

Abs band ct <1500

UA < 10 WBC/hpf

< 5 WBC/hpf stool smear

* No LP required!

CSF < 10

UA < 10 WBC/hpf

CXR clear

WBC < 20,000

Higher risk patients Hospitalize + empiric abx Hospitalize + empiric abx Hospitalize + empiric abx

Lower risk patients Home

No antibiotics

Follow-up required

Home

No antibiotics

Follow-up required

Home

Empiric abx (IM ceftriaxone)

Follow-up required

Statistics

Philadelphia Rochester Boston

SBI (low risk) %

0 1.1 5.4

NPV % 100 98.9 94.6

Sensitivity

%

100 92.4 ?

Are neonates really different?

• Philadelphia criteria applied to 3-28 d• 254 pts, 43% low risk (managed as OP)• 32 (12.6%) with SBI

– 17 UTI’s, 8 OB, 4 BM

• 5 low risk infants has SBI• Would miss 20:1000 of infants with SBI • Empiric antibiotics standard of care in this

age group

Empiric Antibiotics28-90 d

• Lieu, 1992– Decision analysis based on 6 management strategies for

management of fever >38 in 28-90 d infants

• Worst Strategy– Clinical judgement

• Most Effective– Full septic work up, IM ceftriaxone and outpatient

management

Empiric Antibiotics3-36 mos

• Couple of big studies…neither great– Bass, 1993

• 519 children 3-36 mos, 11.6% with OB• Compared clavulin to ceftriaxone in children with T>40 or

T>39.5 and WBC>15• No difference between groups

– Fleisher, 1994• 6733 patients, 2.9% with OB• Compared amoxil to ceftriaxone• “…ceftriaxone eradicated bacteremia, had fewer focal

complications and less persitent fever…”

Us Vs. Them

• Survey of AAP general pediatricians– 610 (67%) responded– 40% indicated that parents frequently ask for

abx when MD feels it is not warranted• 48% stated parents pressure them to prescribe

– 30% stated they comply with that pressure– Parental pressure viewed as leading cause for

unnecessary abx

Us Vs. Them

• Pros– Decreases disomfort

– Dereases parental anxiety

– Extreme may cause brain damage (exceedingly rare)

– Limited/minimal evidence that it may reduce febrile seizures

• Cons– Harm of antipyretics

may outweigh benefits

– Fever is a normal physiologic response

– Fever is usually short lived and benign

– May obscure diagnostic/prognostic signs

Should Fever be Treated?

Us Vs. Them: Pyrexiophobia• 91% of caregivers believed fever was harmful

– 21% listed brain damage and 14% listed death as effects of fever

• 25% gave antipyretics for fever < 37.8

• 85% awakened the child to treat fever– 14% gave acetaminophen too frequently– 44% gave ibuprofen too frequently

• 65% of pediatricians believed fever in and of itself could be dangerous to the child

Changes and Controversies

• Eradication of HiB

• Decreasing Prevalence of Strep pneumo

• Increasing resistance of Strep pneumo

• Fever in infant with recognizable illness

HiB Vaccine (1987)

• Prior to vaccine:– 10-15% of OB and majority of SBI– 12,000 cases/year(US) invasive HiB in <5yo

• 1994-95– 300 cases/year (likely lower now)

• Invasive HiA/F are still uncommon but may emerge as serious pathogens

Prevnar/Pneumovax

• PCV7 (7 serotypes) studied in Northern California• Large herd effect noticed

– 34% of < 5 yo children immunized– 62% reduction in invasive PC seen

• Finnish otitis media study– Strep isolates from OM cultures– Significant reduction in the 7 serotypes– 33% increase in other serotypes

• PCV7 estimated to be 97% effective– Excellent but will still see dz

• Will still see PC in– Other serotypes– Vaccine failures– Unimmunized children– Immunocompromised children

• Bottom line:– Shouldn’t change our respect for OB/SBI in young

children…yet

Prevnar/Pneumovax

Pneumococcal ResistanceKaplan, 1998

• Three year MC study– 1291 systemic pneumococcal infections

• Resistance increased annually over the study period– Penicillin resistance 21%– Ceftriaxone resistance 9%

• Resistance changes region to region– Ottawa has ~20% resistant Strep pneumo

Fever and Recognizable Illness

• Kupperman, 1997– Risk of bacteremia and UTI in febrile children with and

without bronchiolitis• 432 children, 0-24 mos

– Children with bronchiolitis had significantly fewer positive cultures

• Blood 0% compared to 2.7%

• Urine 1.9% compared to 13.6%

• 0 children < 2 mos with bronchiolitis had bacteremia or UTI

• Greene, 1999– 5 year retrospective – Children 3-36 mos with T >39– 1347 children with recognizable viral syndrome

• Croup, varicella, bronchiolitis, stomatitis

– Blood cultures in 65%– 2 of 876 (0.2%) were culture positive

Fever and Recognizable Illness

Occult Pneumonia

• Bachur, 1999• Prospective cohort study

– < 5 yo children with T >39 and WBC > 20k

– CXR in 225/278

• CXR postive in– 40% with suggestive clinical exam

– 26% of those without clinical evidence

• Recommends empiric cxr in fever without source

UTI’s in the Febrile Child

• Most frequent SBI and may present with fever only

• Prevalence 3.3% in febrile infants

• Gorelick, 2000– Clinical Decision Rule

T > 39 fever > 2 days

White race age < 1 year

Absence of another potential source

• All with UTI had at least one risk factor

• Presence of any two factors– Sensitivity 95%– Specificity 31%

UTI’s in the Febrile Child

Febrile Seizures

• Trainor, 1999• Multi-centered analysis of ED management

– 455 children– 1.3% bacteremic– 5.9% UTI– 12.5% abnormal CXR– 135 had LP…all normal

• In other words, manage like any other kid with fever

So…now you’re completely lost!

What are the guidelines?

What do you really need to know?

CPS Guidelines (www.cps.ca)

0-28 days• No CPS guidelines documented for 0-28 d

• American Concensus Guidelines (Baraff, 1993)

– Full Septic Work up (all risk groups)• LP (culture, cell counts and glucose/protein)• Blood culture• Urine (routine, microscopy and culture)• If diarrhea, stool smear and culture• If resp symptoms, CXR

– Admit, + IV antibiotics

CPS Guidelines29-90 days

• NOT low risk

• CPS – “toxic or unduly lethargic”– FSWU (BC,UC,LP)– Admit– Broad spectrum IV antibiotics

• Low Risk– No investigations– Careful outpatient follow up, no treatment

• American Option– FSWU– Ceftriaxone– RTED in 24h for re-assessment

• In reality, somewhere in between

CPS Guidelines29-90 days

• Toxic Appearance– FSWU– Admit– IV antibiotics

CPS Guidelines3-36 months

• Non Toxic, T < 39.5– Observe only (if follow up assured)

• Non Toxic, T >39.5– CBC to decide if BC/UC and empiric therapy are needed– If WBC < 15k observe if follow up assured

• If follow up not assured a more aggressive approach may be indicated.

CPS Guidelines3-36 months

• If treating emprically:– Amoxicillin 60 mg/kg/day or– Ceftriaxone 50 mg/kg– “…,and neither a substitute for for careful

decision-making or follow-up.” Long, 1994

• American guidelines are ceftriaxone

CPS GuidelinesEmpiric Antibiotics

Blood Culture (+) 3-36 mos

• Pneumococcus– Persistent fever

• Admit, FSWU, IV abx

– Afebrile/well-looking• Repeat culture, no treatment

• All other bacteria• Admit, FSWU, IV abx

Case 1• A 3 week old male infant is brought to your ED with a 2 day

history of fever. He was born by uncomplicated vaginal delivery at 37 weeks gestation following a normal pregnancy. At his two week check-up he was noted to be gaining weight appropriately. His vital signs are: T 38.9C (R), HR 140, RR 40, and BP 90/60. He is sleepy but easily rousable. Physical exam is normal apart from a slightly dull left tympanic membrane. His peripheral WBC is 16,000, his UA shows 3 WBC/hpf. BC and UC are sent. Your management at this point would consist of:

a. Discharge on antipyretics with close follow-upb. Discharge on oral amoxicillin with close follow-upc. LP and admission for parenteral antibioticsd. CXR to r/o pneumoniae. Stool for analysis and culture, and outpatient follow-up

Case 2

• A 7 week old girl is referred in to ED for evaluation of a rectal temperature of 39.2C. Her PE is normal. Her UA is negative, her WBC is 9,000 (70% neuts, 28% lymphs, 2% bands), and her LP reveals a CSF WBC count of 8. BC, UC, and CSF cultures are sent. Acceptable management options for this child would include any one of the following except:

a. IM ceftriaxone in the EDb. Admission to the hospital for IV antibioticsc. Discharge with follow-up in 24 hoursd. Admission to the hospital for observatione. Discharge on amoxicillin

Case 3

• A 19 month old boy comes to the ED with a 3 day history of fever. He appears well but his tympanic T is 39.8C. His chest is clear, his abdomen is soft, and he is circumcised. No source can be found for his fever. A CBC reveals a WBC of 8200 (60% neuts, 27% bands). BC’s are sent.

Appropriate management at this point will be to:

a. Obtain a urine sampleb. Administer IM ceftriaxonec. Perform an LPd. Obtain a CXRe. Discharge on antipyretics

After all that….Here’s what you need to know!

• Infants < 28 days:

• Infants 1-3 months

• Infants and children 3 months to 3 yrs (T < 39C):

• Infants and children 3 months to 3 years (T 39C):

hospitalize +/- abx

+/- labs, home, +/- abx

home, no antibiotics

+/- labs, home, no antibiotics