title: Variation of Circulating Inflammatory Mediators in Staphylococcus aureus and Escherichia coli Bloodstream Infection.
abstract: BACKGROUND
  The aim of this study was to examine the behavior of circulating inflammatory mediators and to exclude gram-positive from gram-negative bloodstream infections. Results may be helpful in selection of optimal specific antibiotic therapies.
  
  
  METHODS
  Mice (25-27 g) were randomized to 3 groups infected with Staphylococcus aureus (S. aureus) ATCC 25923, Escherichia coli (E. coli) ATCC 25922, or phosphate-buffered saline (PBS). The white blood cell count (WBC) and the concentrations of serum C-reactive protein (CRP), procalcitonin (PCT), interleukin (IL)-1α, IL-1β, IL-6, IL-10, monocyte chemotactic protein-1 (MCP-1), and macrophage inflammatory protein-1α (MIP-1α) were detected in blood samples at different time intervals after intravenous tail injection.
  
  
  RESULTS
  The results showed that compared to the control mice, infected animals exhibited significantly higher levels of all mediators after bacterial infection. Moreover, compared to the mice that received S. aureus, animals with E. coli infection showed significantly greater increases in serum IL-1α, IL-1β, IL-6, MCP-1, and MIP-1α levels.
  
  
  CONCLUSIONS
  These results suggest that the use of the analyzed serum markers at an early stage of bloodstream infection may give useful information for the clinician to distinguish gram-negative from gram-positive infections.
authors.affiliation: Department of Clinical Laboratory Medicine, Chinese PLA General Hospital, Beijing, China (mainland).
authors.forename: Jinyan
authors.initials: J
authors.lastname: Duan
authors.affiliation: Department of Clinical Laboratory Medicine, Chinese PLA General Hospital, Beijing, China (mainland).
authors.forename: Yinjing
authors.initials: Y
authors.lastname: Xie
authors.affiliation: Department of Microbiology, Chinese PLA General Hospital, Beijing, China (mainland).
authors.forename: Jiyong
authors.initials: J
authors.lastname: Yang
authors.affiliation: Department of Microbiology, Chinese PLA General Hospital, Beijing, China (mainland).
authors.forename: Yanping
authors.initials: Y
authors.lastname: Luo
authors.affiliation: Department of Clinical Laboratory Medicine, Chinese PLA General Hospital, Beijing, China (mainland).
authors.forename: Yuni
authors.initials: Y
authors.lastname: Guo
authors.affiliation: Department of Clinical Laboratory Medicine, Chinese PLA General Hospital, Beijing, China (mainland).
authors.forename: Chengbin
authors.initials: C
authors.lastname: Wang
mesh_terms: D000818:Animals; D001835:Body Weight; D002097:C-Reactive Protein / Q000378:metabolism; D015169:Colony Count, Microbial; D016207:Cytokines / Q000097:blood; D004926:Escherichia coli / Q000502:physiology*; D004927:Escherichia coli Infections / Q000097:blood* / Q000382:microbiology*; D018836:Inflammation Mediators / Q000097:blood*; D007958:Leukocyte Count; D008099:Liver / Q000473:pathology; D008297:Male; D008813:Mice, Inbred ICR; D013203:Staphylococcal Infections / Q000097:blood* / Q000382:microbiology*; D013211:Staphylococcus aureus / Q000502:physiology*
chemical_list: D016207:Cytokines; D018836:Inflammation Mediators; D002097:C-Reactive Protein