PURPOSE: Timely knowledge of the bacterial etiology and localization of infection are important for empirical antibiotic therapy. Thus, the goal of this study was to evaluate routinely used biomarkers together with novel laboratory parameters in the diagnosis of infection. METHODS: In this prospective study, 54 adult patients with bacterial infections admitted to the Department of Infectious Diseases were included. For comparison, 27 patients with viral infections were enrolled. In these patients, white blood cell (WBC) counts, differential blood counts, serum levels of procalcitonin (PCT), IL-1β, IL-6, IL-8, IL-10, IL-12, TNF-α, IFN-γ, soluble CD14 (sCD14), heparin-binding protein (HBP), cortisol (Cort), and monocyte surface expression of TLR2, TLR4, HLA-DR, and CD14 were analyzed. Also, these biomarkers were evaluated in 21 patients with acute community-acquired bacterial pneumonia (CABP), as well as in 21 patients with pyelonephritis and urosepsis. RESULTS: The highest sensitivity and specificity (expressed as the area under the curve [AUC]) for bacterial infection were observed in serum concentration of PCT (0.952), neutrophil and lymphocyte counts (0.852 and 0.841, respectively), and serum levels of HBP (0.837), IL-6 (0.830), and Cort (0.817). In addition, the serum levels of IFN-γ and Cort were significantly higher and IL-8 levels were lower in CABP when compared to pyelonephritis or urosepsis. CONCLUSIONS: From the novel potential biomarkers, only PCT demonstrated superiority over the routine parameters in the differentiation of bacterial from viral infections. However, some of the novel parameters should be further evaluated in larger and better characterized cohorts of patients in order to find their clinical applications.

• MeSH
• Bacterial Infections blood   diagnosis   MeSH
• Biomarkers MeSH
• Adult MeSH
• Community-Acquired Infections blood   diagnosis   MeSH
• Calcitonin * blood   MeSH
• Middle Aged MeSH
• Humans MeSH
• Urinary Tract microbiology   MeSH
• Calcitonin Gene-Related Peptide MeSH
• Predictive Value of Tests MeSH
• Prospective Studies MeSH
• Protein Precursors * blood   MeSH
• Pyelonephritis blood   diagnosis   MeSH
• Sensitivity and Specificity MeSH
• Sepsis blood   diagnosis   MeSH
• Severity of Illness Index MeSH
• Virus Diseases blood   diagnosis   MeSH
• Check Tag
• Adult MeSH
• Middle Aged MeSH
• Humans MeSH
• Male MeSH
• Female MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Comparative Study MeSH
• Geographicals
• Czech Republic MeSH
• Names of Substances
• Biomarkers MeSH
• CALCA protein, human MeSH Browser
• Calcitonin * MeSH
• Calcitonin Gene-Related Peptide MeSH
• Protein Precursors * MeSH