Objective: Patients with sepsis constitute a significant proportion of critically ill patients. Although outcomes have significantly improved in the last decade, mortality still remains high 25-30% and 40-50% when shock is present. Procalcitonin has been studied in sepsis for diagnosis, and guidance of antibiotic therapy. We investigated the levels of C-reactive protein (CRP) and procalcitonin in patients with bacteremia seen in various departments of the hospital and to evaluate the possible discriminative role of procalcitonin in differentiating bacterial etiology of infection.

Materials and methods: Serum procalcitonin and CRP levels of patients with Gram negative and positive bacteremia were recorded retrospectively. CRP and procalcitonin levels of 407 consecutive patients with 636 positive blood cultures were included in the study. The blood cultures were first grouped as Gram-positive bacteremia (GPB) and Gram-negative bacteremia (GNB). 316 (49.7%) of 636 positive blood culture were in GPB group. GNB group was further divided into Enterobacteriaceae bacteremia (GNEB) and Non-Enterobacteriaceae (GNNEB).

Results: Procalcitonin levels of GNB and GPB groups were significantly different (P= 0.0001). Procalcitonin and CRP levels of GNEB and GNNEB groups were also significantly different (P=0.015 and P= 0.003, respectively).

Conclusion: Our findings suggest that procalcitonin levels may be discriminative between GNB and GPB groups and levels >4.055 ng/mL may be evidence of GNB.