1578 The Correlation Between C-Reactive Protein and Serious Bacterial Infection in a Tertiary Paediatric Emergency Department: An Observational Case-Controlled Cohort Study

Background and Aims C-Reactive Protein (CRP) is a common component of the blood panel in children being investigated for the considered diagnosis of serious bacterial infection (SBI). We aimed to correlate CRP values to SBI in a paediatric population. Methods This is a retrospective study from 2007–2009 of all patients with CRP greater than 100mg/L. Controls were randomly selected age-matched patients with a CRP less than 100mg/L. SBI was defined as bacterial meningitis, bacteraemia, urinary tract infection, pneumonia, osteomyelitis, septic arthritis, appendicitis or abscess formation confirmed by microbiological investigations and/or supporting radiology and ultimate clinical diagnosis. Results 570/10,191 patients had a CRP > 100mg/L. 496 patients were controls 424 patients had SBI. A significant difference between the non-SBI group (n= 642), 35±68mg/L (median±standard deviation), compared to the SBI group (n=424), 141±87mg/L, existed. The absolute and ratio risk of SBI increased consistently with rising CRP values (Table 1). Abstract 1578 Table 1 Incidence, Absolute & Ratio Risks for SBI CRP Range Incidence of SBI Total cases Absolute Risk Ratio Risk 0–20 20 248 8% 0.08 21–100 39 181 21% 0.27 101–150 174 365 48% 0.92 151–200 83 134 62% 1.63 201–250 43 64 67% 2.03 251–300 44 52 84% 5.25 301+ 21 22 95% 21.2 Conclusion This multi-layered risk evaluation should aid the future management of children attending the PED being investigated for SBI.