C-reactive protein as a marker of serious bacterial infections in hospitalized febrile infants

Acta Paediatr. 2009 Nov;98(11):1776-80. doi: 10.1111/j.1651-2227.2009.01469.x. Epub 2009 Aug 6.


Objective: To determine the potential predictive power of C-reactive protein (CRP) as a marker of serious bacterial infection (SBI) in hospitalized febrile infants aged < or =3 months.

Patients and methods: Data on blood CRP levels were collected prospectively on admission for all infants aged < or =3 months who were hospitalized for fever from 2005 to 2008. The patients were divided into two groups by the presence or absence of findings of SBI.

Results: A total of 892 infants met the inclusion criteria, of whom 102 had a SBI. Mean CRP level was significantly higher in the infants who had a bacterial infection than in those who did not (5.3 +/- 6.3 mg/dL vs. 1.3 +/- 2.2 mg/dL, p < 0.001). The area under the ROC curve (AUC) was 0.74 (95% CI: 0.67-0.80) for CRP compared to 0.70 (95% CI: 0.64-0.76) for white blood cell (WBC) count. When analyses were limited to predicting bacteremia or meningitis only, the AUCs for CRP and WBC were 0.81 (95% CI: 0.66-0.96) and 0.63 (95% CI: 0.42-0.83), respectively.

Conclusion: C-reactive protein is a valuable laboratory test in the assessment of febrile infants aged < or =3 months old and may serve as a better diagnostic marker of SBI than total WBC count.

MeSH terms

  • Analysis of Variance
  • Bacterial Infections / blood
  • Bacterial Infections / diagnosis*
  • Biomarkers / blood
  • C-Reactive Protein / analysis*
  • Female
  • Fever / blood
  • Fever / microbiology*
  • Hospitalization
  • Humans
  • Infant
  • Infant, Newborn
  • Leukocyte Count
  • Logistic Models
  • Male
  • Observation
  • Prospective Studies
  • Sensitivity and Specificity
  • Severity of Illness Index


  • Biomarkers
  • C-Reactive Protein