Validation of a laboratory risk score
for the identification of severe
bacterial infection in children with
fever without source
Galetto-Lacour A, Zamora S, Andreola B, Bressan
S, Lacroix L, Da Dalt L and Gervaix A
Arch Dis Child 2010; 95: 968-973
Dr Vanessa Craven
Procalcitonin
2 ng/ml
0.5 ng/ml
0.05 ng/ml
Healthy
Individuals
Local
Infections
Systemic
Infections
(Sepsis)
Severe
Sepsis
Septic
Shock
Brunkhorst FM et al. Intens. Care Med 1998; 24: 888-892
Pediatr Infect Dis J 2008; 27: 654-6
• 202  7- 36 months
• Rectal temp >38°C & no focus
•
•
•
•
•
IOS
Urine MC&S
WCC, CRP & PCT
LP ‘when meningitis suspected’
Clinical follow up within 48 hours
Results
• SBI 54 (27%)
• PCT: OR 37.6 (5.8 - 243)
• CRP: OR 7.8 (2 - 30.4)
• Urine dipstick:
OR 23.2 (5.1 - 104.8)
Predictor
Points
PCT (ng/ml)
< 0.5
≥ 0.5
≥ 2.0
0
2
4
CRP (mg/ml)
< 40
40-99
≥ 100
0
2
4
Urine dipstick
Negative
Positive
0
1
AIM
• External validation
• More children
• 2007 Italian population
• Laboratory score ≥ 3
Methodology
•
•
•
•
Prospective enrolment - 408 children
Data from Italian study
May 2004 - October 2005
7 days (>38C) to 36 months (>39.5°C)
7 days to 36 months
Fever without source
Exclusion criteria
Looking for severe bacterial
infection (defined) – diagnosis
‘at end of follow up’
SBI vs ‘benign viral infection’
Retrospective (5 years)
Using another study’s
cohort
Reasonable age definition & exclusion
criteria
Using another study’s data set
Higher temperature cut off than used
in practice?
Laboratory measurements
Who confirmed FWS?
ALL were assessed at 72 hours
(including telephone contact) – no
details
Cultures would be back but not always
reliable
What happened to the classification of
children that did not improve? Or had
focal infection and did not get Abx
DMSA to diagnose pyleonephritis
(1/52)
Who did the assessments?
Who followed up?
ALL were followed up
No details about
- follow up length
- location
Was 72 hr review conclusive in
all
Any need Abx/admission
What happened to the ‘focal
bacterial infection’ 15.8%?
SBI in 92 (22.7%)
Score ≥3: Sens 86% (77-92%)
Spec: 83% (79-87%)
Sens ↑and spec ↓ with age
WBC: Sens 52%, Spec 75%
CRP: Sens 52%, Spec 75%
PCT: Sens 75%, Spec 76%
Missed 13 cases
Very large confidence intervals!
Large confidence
intervals
Selected population
BUT referral pathway different
WCC poor predictor
Pediatr Infect Dis J 2008; 27:
654-6
Results comparable to derivation
set
Summary & Conclusion
There is insufficient evidence to support the sole use of
the lab score to identify those with severe bacterial
infection