Early signaling of bacteremia in patients who present to the department of emergency medicine with relatively low C-reactive protein (CRP) concentrations

Objectives: Examining the usefulness of C-reactive protein velocity (CRPv) as an early biomarker for the presence of bacteraemia in patients presenting to the Department of Emergency Medicine with acute infection/inflammation and suspected bacteraemia. Methods: A retrospective study examining a cohort of patients who presented to the E.R and in whom blood cultures were taken. CRPv was calculated as the difference in mg/hour/litter between two consecutive CRP tests performed within 12 h. Results: 256 patients were included in the cohort. Using CRPv in patients who at first presented with a relatively low (17.9 ≤ mg/L 1st quartile) CRP concentration, we found an AUC of 0.808 ± 0.038 (p < 0.001) for the presence of positive versus negative blood cultures (what is AUC?). This was better than the AUC that was obtained when the WBC for the same purpose. Conclusions: CRPv may be a useful biomarker in the identification of patients with suspected bacteremia and a low CRP-a challenging situation for clinicians who may underestimate the severity of illness in this patient group.