Am Fam Physician. 2016;94(11):933
Clinical Question
Is the Step-by-Step approach useful for ruling out systemic infection in young low-risk infants?
Bottom Line
The Step-by-Step approach, using a basic physical examination and readily available urine and blood tests (without lumbar puncture; see the Synopsis section), can successfully identify low-risk infants younger than 90 days who will not need empiric antibiotic treatment and lumbar puncture. However, this approach has not been studied (nor has any other approach, I believe) in a randomized controlled trial to see whether it is effective at decreasing lumbar punctures or hospital admissions. (Level of Evidence = 1a)
Synopsis
This study was conducted at 11 European pediatric emergency departments. The researchers enrolled 2,185 previously healthy term infants younger than 90 days with fever without source. The relatively new Step-by-Step approach was evaluated in comparison with the Rochester criteria or the Lab-score (Arch Dis Child. 2010;95(12):968–973), both methods of ruling out invasive bacterial infection. All infants were evaluated via urine dipstick, a urine culture, white blood cell count, C-reactive protein level, procalcitonin, and blood culture. Eventually, 4% (n = 87) of the infants were given a diagnosis of systemic infection and approximately 45% (n = 991) were classified as low-risk using the Step-by-Step approach. Sensitivity and negative predictive value for ruling out infection were 92.0% and 99.3% for the Step-by-Step approach, 81.6% and 98.3% for the Rochester criteria, and 59.8% and 98.1% for the Lab-score. Seven of the 991 infants (0.7%) who were classified as low risk by the score were found to have a systemic infection using the Step-by-Step approach.
The Step-by-Step approach: Children at low risk of systemic infection have the following characteristics: not ill-appearing, younger than 21 days, no leukocyturia, procalcitonin level less than 0.5 ng per mL, C-reactive protein level less than 20 mg per L (190.5 nmol per L), and absolute neutrophil count less than 10,000 per mm3 (10.0 × 109 per L).
Study design: Decision rule (validation)
Funding source: Self-funded or unfunded
Setting: Emergency department
Reference: GomezBMintegiSBressanSDa DaltLGervaixALacroixLEuropean Group for Validation of the Step-by-Step ApproachValidation of the “Step-by-Step” approach in the management of young febrile infants. Pediatrics2016;138(2):e20154381.
