title: Establishing a biomarker for postoperative ileus in humans - Results of the BiPOI trial.
abstract: OBJECTIVE
  Postoperative ileus (POI) is a frequent complication after abdominal surgery, resulting from an inflammation of the muscularis externa (ME). So far no valid biomarker for occurrence, duration or intensity of POI exists. Extravasation of monocytes and neutrophils from blood circulating into the postoperative ME is well known as a hallmark of POI. In a previous study we demonstrated that a low abundant subset of TH1 cells, activated by IL-12, can be detected in the peripheral blood of a small subset of patients in response to abdominal surgery. The aim of the present study was to investigate if these specific TH1 cells, IL-12 or circulating leukocyte levels could act as a valid marker for POI occurrence.
  
  
  METHODS
  At different time points, blood samples of patients undergoing abdominal or extraabdominal surgery were collected. Serum levels of IL-12 or TH1 cells as well as neutrophils and monocytes were analyzed. Data were compared between both groups and correlated with clinical signs of POI.
  
  
  RESULTS
  Time until first flatus and defecation as well as solid food tolerances are delayed after abdominal compared to extraabdominal surgery. Circulating IL-12 levels and numbers of TH1 cells, neutrophils and monocytes did not differ between both groups.
  
  
  CONCLUSIONS
  While previous experiments indicated that specific TH1 cells play a crucial role in POI dissemination, our present data from a larger human cohort demonstrate that they do not seem to be suitable to distinguish between abdominal and extraabdominal surgery. Furthermore neither TH1 cells nor leukocytes or serum IL-12 levels are appropriate biomarkers for POI in a clinical setting.
authors.affiliation: Department of Surgery, University of Bonn, Sigmund-Freud-Str. 25, 53127 Bonn, Germany. Electronic address: tim.vilz@ukb.uni-bonn.de.
authors.forename: Tim O
authors.initials: TO
authors.lastname: Vilz
authors.affiliation: Department of Surgery, University of Bonn, Sigmund-Freud-Str. 25, 53127 Bonn, Germany.
authors.forename: Lisa
authors.initials: L
authors.lastname: Roessel
authors.affiliation: Department of Surgery, University of Bonn, Sigmund-Freud-Str. 25, 53127 Bonn, Germany.
authors.forename: Johannes
authors.initials: J
authors.lastname: Chang
authors.affiliation: Department of Surgery, University of Bonn, Sigmund-Freud-Str. 25, 53127 Bonn, Germany.
authors.forename: Dimitrios
authors.initials: D
authors.lastname: Pantelis
authors.affiliation: Department of Surgery, University of Bonn, Sigmund-Freud-Str. 25, 53127 Bonn, Germany.
authors.forename: Timo
authors.initials: T
authors.lastname: Schwandt
authors.affiliation: Department of Surgery, University of Bonn, Sigmund-Freud-Str. 25, 53127 Bonn, Germany.
authors.forename: Arne
authors.initials: A
authors.lastname: Koscielny
authors.affiliation: Department of Surgery, University of Bonn, Sigmund-Freud-Str. 25, 53127 Bonn, Germany.
authors.forename: Sven
authors.initials: S
authors.lastname: Wehner
authors.affiliation: Department of Surgery, University of Bonn, Sigmund-Freud-Str. 25, 53127 Bonn, Germany.
authors.forename: Joerg C
authors.initials: JC
authors.lastname: Kalff
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015415:Biomarkers / Q000097:blood; D015331:Cohort Studies; D013505:Digestive System Surgical Procedures / Q000009:adverse effects; D005260:Female; D006801:Humans; D045823:Ileus / Q000097:blood* / Q000175:diagnosis*; D018664:Interleukin-12 / Q000097:blood; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications / Q000097:blood* / Q000175:diagnosis*; D018417:Th1 Cells / Q000378:metabolism
chemical_list: D015415:Biomarkers; D018664:Interleukin-12
keywords: Animal model; Biomarker; Gastrointestinal field effect; IL-12; Postoperative ileus; Translational research