Sepsis biomarkers for early diagnosis of bacteremia in emergency department

Introduction: We compared the diagnostic values of individual and composite biomarkers used in the prediction of bacteremia in adult emergency department patients.

Methodology: First-hour blood levels of C- reactive protein, procalcitonin, interleukin-6, lactate, lipopolysaccharide-binding protein and white blood cell count were collected from a 30-person control group and 47 adult patients. Patients included in this study were admitted to the emergency department on suspicion of sepsis. We categorized patients according to presence/absence of sepsis and bacteremia. Our control group was categorized as S-B -, septic patients with bacteremia were S+B+, and septic patients without bacteremia were S+B-.

Results: All biomarkers showed a statistically significant elevation when S+B- and S+B+ groups were compared with the S-B-. When S+B+ group was compared with the S+B- group only procalcitonin and lactate levels had statistically significant elevation (p < 0.005). Regression analysis demonstrated that lactate and procalcitonin were independently associated with having bacteremia in the state of sepsis and Hosmer-Lemeshow score was 0.772. The areas under the curve (AUC) values of biomarkers procalcitonin, lactate, C-reactive protein, combined 1 (procalcitonin+ lactate), and combined 2 (procalcitonin + lactate + C-reactive protein) were 0.773, 0.744, 0.523, 0.806, and 0.829 respectively.

Conclusions: Combination of tests such as combined 1 or combined 2 were highly predictive of bacteremia in adult septic patients. Combined 2 demonstrated the best predictive performance and could be utilized as a tool to assist diagnosis of bacteremia before culture results are available.