Revising the Decision Analysis For Febrile Children At Risk For Occult

Bacteremia In a Future Era of Widespread Pneumococcal

Immunization

Revising the Decision Analysis For Febrile Children At Risk For Occult

Bacteremia In a Future Era of Widespread Pneumococcal

Immunization

Loren G. Yamamoto, MD, MPH, MBALoren G. Yamamoto, MD, MPH, MBA

University of Hawaii John A. Burns School of MedicineUniversity of Hawaii John A. Burns School of Medicine

Kapiolani Medical Center For Women And ChildrenKapiolani Medical Center For Women And Children

Febrile Children at Risk for Occult BacteremiaFebrile Children at Risk for Occult Bacteremia

3 to 36 months3 to 36 monthsTemp > 39 C (102.2 F)Temp > 39 C (102.2 F)No reliable source of fever No reliable source of fever

identifiedidentifiedLooks good clinicallyLooks good clinically

StrategiesStrategies

(X) Obs: Observation(X) Obs: Observation (Y) CBC: CBC first. If WBC high, (Y) CBC: CBC first. If WBC high,

then BC+Abx. If WBC low, then BC+Abx. If WBC low, observe.observe.

(Z) BC+Abx: Blood culture and (Z) BC+Abx: Blood culture and empiric antibiotics for all.empiric antibiotics for all.

Abx: Antibiotics without testing.Abx: Antibiotics without testing.

Decision AnalysisDecision Analysis

Compares outcome variables of Compares outcome variables of the different strategiesthe different strategies

Based on multiple assumptionsBased on multiple assumptions What outcome variable should be What outcome variable should be

used? Death and neurologic used? Death and neurologic disabilitydisability

Previous Decision AnalysesPrevious Decision Analyses

Kramer: Observation superiorKramer: Observation superior Lieu: BC+Abx superiorLieu: BC+Abx superior Downs: BC+Abx superiorDowns: BC+Abx superior Yamamoto: Depends on Yamamoto: Depends on

assumption of negative assumption of negative consequences of unnecessary consequences of unnecessary treatmenttreatment

HiB Freq 10%, NCT 0.0001, Abx efficacy 80%

0

20

40

60

80

100

0 5% 10% 15% 20%

Bacteremia Frequency

Death

s &

Neuro

Sequela

e

X (Obs)

Y (CBC)

Z (BC+Abx)

Bacteremia 4%, NCT 0.0001, HiB Freq 10%

0

10

20

30

40

50

0 20% 40% 60% 80% 100%

Empiric Antibiotic Efficacy

Death

s &

Neuro

Sequela

e X (Obs)

Y (CBC)

Z (BC+Abx)

Negative Consequences of TrmtNegative Consequences of Trmt

Allergic reactions from antibiotics.Allergic reactions from antibiotics. Pain from testing.Pain from testing. Monetary cost.Monetary cost. Amplification factor.Amplification factor. Anxiety factor.Anxiety factor. Excessive antibiotic use - ? resistanceExcessive antibiotic use - ? resistance

New ConsiderationsNew Considerations

Widespread HiB vaccineWidespread HiB vaccine Widespread pneumococcal vaccineWidespread pneumococcal vaccine

HiB vaccineHiB vaccine

HiB essentially eliminatedHiB essentially eliminated Only one serotypeOnly one serotype Overall reduction in morbidity and Overall reduction in morbidity and

mortalitymortality Does not change the RANKING of the Does not change the RANKING of the

strategies X, Y, Zstrategies X, Y, Z

Bacteremia 4%, NCT 0.0001, Abx Efficacy 80%

0

10

20

30

40

50

0 10% 20% 30%

HiB Frequency

Death

s &

Neuro

Sequela

e

X (Obs)

Y (CBC)

Z (BC+Abx)

Pneumococcal vaccinePneumococcal vaccine

Highly efficacious in preliminary Highly efficacious in preliminary studiesstudies

Covers limited number of serotypesCovers limited number of serotypes Probably reduces risk of bacteremiaProbably reduces risk of bacteremia Likely to become widespread in the Likely to become widespread in the

near futurenear future

Decision analysis assumptionsDecision analysis assumptions

MultipleMultiple Beyond the scope of this Beyond the scope of this

presentationpresentation Standard assumptions which Standard assumptions which

have been used in previous have been used in previous decision analysisdecision analysis

Overall morbidity/mortality reducedOverall morbidity/mortality reduced

For strategies X (Obs), Y (CBC+) and Z (BC+Abx), bad outcomes per 100,000:

Pre-HiB vaccine era: 76, 36, 17 Post-HiB vaccine era: 37, 25, 15 Future era of widespread

pneumococcal vaccine (at 80% efficacy): 15, 10, 13

ConclusionsConclusions

Overall morbidity/mortality reducedOverall morbidity/mortality reduced RANKING of strategies largely RANKING of strategies largely

unaffected by pneumococcal vaccine unaffected by pneumococcal vaccine efficacy, but more so dependent on efficacy, but more so dependent on negative consequences of treatment negative consequences of treatment assumption.assumption.

The magnitude of the differences The magnitude of the differences between strategies is smaller.between strategies is smaller.

ConclusionsConclusions

Since the difference between Since the difference between strategies X, Y, Z are small, consider strategies X, Y, Z are small, consider them similar.them similar.

Social factors surrounding the patient Social factors surrounding the patient encounter may be important in encounter may be important in selecting a strategyselecting a strategy

Social FactorsSocial Factors

Patient observation and follow-up Patient observation and follow-up reliability.reliability.

Parents demand tests and antibiotics.Parents demand tests and antibiotics. Parents’ fear of tests.Parents’ fear of tests. Parents are lawyers, physicians, etc.Parents are lawyers, physicians, etc. Primary care office versus emergency Primary care office versus emergency

department.department.