title: Soluble urokinase-type plasminogen activator levels are related to plasma cytokine levels but have low predictive value for mortality in trauma patients.
abstract: BACKGROUND
  Soluble urokinase-type plasminogen activator (suPAR) represents a marker for immune activation and has predictive value in critically ill patients. The kinetics of suPAR and its correlation with the immune response and outcome in trauma patients are unknown.
  
  
  METHODS
  Plasma concentrations of inflammatory cytokines and suPAR were determined in adult trauma patient (n = 69) samples obtained by the Helicopter Emergency Medical Services at arrival at the emergency department (ED) and at days 1, 3, 5, 7, 10, and 14.
  
  
  RESULTS
  Initial suPAR levels were unrelated to injury severity score and higher in nonsurvivors compared with survivors, although no difference was observed between early and late mortality. The area under the receiver operating characteristic curve to predict mortality was 0.6 (95% confidence interval, 0.48-0.72). Soluble urokinase-type plasminogen activator levels increased over time in 94% of patients, although suPAR increase did not precede death. Tumor necrosis factor α at the ED correlated with suPAR at that time point, whereas concentrations of other proinflammatory cytokines at the ED correlated with suPAR levels at days 1 and 5.
  
  
  CONCLUSIONS
  After trauma, initial suPAR plasma concentrations are higher in nonsurvivors compared with survivors, but its predictive value is low. Soluble urokinase-type plasminogen activator levels increase over time after trauma, and concentrations at later time points are related to cytokine levels at the ED.
authors.affiliation: Department of Intensive Care Medicine, Radboud University Medical Center, Nijmegen, The Netherlands; Department of Anaesthesiology, Radboud University Medical Center, Nijmegen, The Netherlands. Electronic address: kim.timmermans@radboudumc.nl.
authors.forename: Kim
authors.initials: K
authors.lastname: Timmermans
authors.affiliation: Department of Anaesthesiology, Radboud University Medical Center, Nijmegen, The Netherlands; Helicopter Emergency Medical Service, Radboud University Medical Center, Nijmegen, The Netherlands. Electronic address: michiel.vaneker@radboudumc.nl.
authors.forename: Michiel
authors.initials: M
authors.lastname: Vaneker
authors.affiliation: Department of Anaesthesiology, Radboud University Medical Center, Nijmegen, The Netherlands. Electronic address: gertjan.scheffer@radboudumc.nl.
authors.forename: Gert Jan
authors.initials: GJ
authors.lastname: Scheffer
authors.affiliation: Department of Intensive Care Medicine, Radboud University Medical Center, Nijmegen, The Netherlands; Department of Anaesthesiology, Radboud University Medical Center, Nijmegen, The Netherlands. Electronic address: paulinemaassen@gmail.com.
authors.forename: Pauline
authors.initials: P
authors.lastname: Maassen
authors.affiliation: Department of Intensive Care Medicine, Radboud University Medical Center, Nijmegen, The Netherlands; Department of Anaesthesiology, Radboud University Medical Center, Nijmegen, The Netherlands. Electronic address: stephanie.janssen@gmail.com.
authors.forename: Stephanie
authors.initials: S
authors.lastname: Janssen
authors.affiliation: Department of Intensive Care Medicine, Radboud University Medical Center, Nijmegen, The Netherlands; Department of Anaesthesiology, Radboud University Medical Center, Nijmegen, The Netherlands. Electronic address: matthijs.kox@radboudumc.nl.
authors.forename: Matthijs
authors.initials: M
authors.lastname: Kox
authors.affiliation: Department of Intensive Care Medicine, Radboud University Medical Center, Nijmegen, The Netherlands. Electronic address: peter.pickkers@radboudumc.nl.
authors.forename: Peter
authors.initials: P
authors.lastname: Pickkers
mesh_terms: D000328:Adult; D000368:Aged; D016638:Critical Illness; D016207:Cytokines / Q000097:blood*; D005260:Female; D006801:Humans; D015601:Injury Severity Score; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D012372:ROC Curve; D055293:Receptors, Urokinase Plasminogen Activator; D016019:Survival Analysis; D014568:Urokinase-Type Plasminogen Activator / Q000097:blood*; D014947:Wounds and Injuries / Q000097:blood* / Q000276:immunology / Q000401:mortality*
chemical_list: D016207:Cytokines; D055293:Receptors, Urokinase Plasminogen Activator; D014568:Urokinase-Type Plasminogen Activator
keywords: Biomarkers; Cytokines; Inflammation; Trauma; suPAR