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Step-by-Step approach to febrile infants
Sequential risk stratification for invasive bacterial infection.
Step-by-Step approach to febrile infants
Ill-appearing on clinical assessment
Age
days
Leukocyturia on urine dipstick/microscopy (positive leukocyte esterase or nitrites, or pyuria)
Procalcitonin
ng/mL
C-reactive protein
mg/L
Absolute neutrophil count
/mm³
Complete the fields above to see the result.
When to use
- Sequential (stepwise) risk stratification of infants <=90 days old with fever without a source in the emergency department.
Formula
Sequential decision rule: (1) ill appearance -> high risk; (2) age <=21 days -> high risk; (3) leukocyturia -> intermediate risk; (4) procalcitonin >=0.5 ng/mL -> intermediate risk; (5) CRP >=20 mg/L or ANC >=10,000/mm³ -> intermediate risk; otherwise low risk.
Pearls and pitfalls
- In the prospective multicenter validation, sensitivity and NPV for invasive bacterial infection were 92.0% and 99.3%, outperforming the Rochester criteria and the Lab-score.
- Use caution in infants presenting within about 2 hours of fever onset, since inflammatory markers may not yet have risen.