Step-by-Step Approach to Febrile Infants
Sequential rule for well and unwell febrile infants ≤ 90 days old with fever without source (Gomez 2016): appearance, age, urinalysis, procalcitonin, then CRP and neutrophil count, to identify infants at low risk of invasive bacterial infection (IBI).
Score interpretation
Well-appearing, > 21 days, no leukocyturia, procalcitonin < 0.5 ng/mL, CRP ≤ 20 mg/L and ANC ≤ 10 × 10⁹/L. IBI in 0.7% of low-risk infants (negative predictive value 99.3%, Gomez 2016).
→ May be managed without lumbar puncture or empirical antibiotics, with observation, close follow-up and safety-net advice.
No high-risk feature, but CRP > 20 mg/L or ANC > 10 × 10⁹/L.
→ Blood culture and admission for observation; consider lumbar puncture and empirical antibiotics per local guidance. Paediatric review.
Ill-appearing, ≤ 21 days old, leukocyturia or procalcitonin ≥ 0.5 ng/mL.
→ Full septic workup (blood culture, urine culture, lumbar puncture) and empirical IV antibiotics per local guidance; admit to the paediatric ward or PICU.
Interpretation bands for the Step-by-Step Febrile. Apply clinical judgement and local guidance.
References
- Gomez B, et al. Validation of the 'Step-by-Step' Approach in the Management of Young Febrile Infants. Pediatrics. 2016;138(2):e20154381.
- Mintegi S, et al. Accuracy of a sequential approach to identify young febrile infants at low risk for invasive bacterial infection. Emerg Med J. 2014;31:e11.
Related
Curated clinical cross-links plus same-class fallbacks.
- Gentamicin (Paediatric) · Aminoglycoside — Neonatal Sepsis / Gram-Negative Infections in Children
- Phenobarbital (Paediatric Epilepsy — Beyond Neonatal) · Barbiturate Anticonvulsant
- Diazepam (Paediatric) · Benzodiazepine — Status Epilepticus / Febrile Convulsions (Community)
- Dexamethasone (Paediatric) · Corticosteroid — Croup / Bacterial Meningitis / Post-Extubation Stridor / Cerebral Oedema
- Ceftriaxone (Paediatric) · Third-Generation Cephalosporin — Meningitis / Sepsis / Community-Acquired Pneumonia
- Aciclovir (Paediatric) · Antiviral — HSV Encephalitis / Neonatal Herpes / VZV in Immunocompromised
Decision support only — verify against a current formulary, NICE, or your local guideline before clinical use.