title: Plasma citrulline after small bowel transplantation: effect of time from transplantation, acute cellular rejection, and renal failure.
abstract: BACKGROUND
  Plasma citrulline concentration (CIT) depends on its synthesis by enterocytes and its catabolism by renal tubules. To evaluate CIT applicability as a marker of acute cellular rejection (ACR) after intestinal transplantation (ITx), CIT was investigated according to time from ITx, episodes of ACR, and creatinine clearance (CrCl).
  
  
  METHODS
  Twenty-four adult ITx recipients were prospectively studied. The results were compared with those of 19 healthy controls (HCs) and of 29 patients with chronic renal failure (CRF).
  
  
  RESULTS
  In ITx recipients, CIT was lower than in HCs during the first two postoperative weeks; it then progressively increased and reached the range observed in HCs, approximately between the 31st and the 45th postoperative day. A positive association with postoperative days (R = 0.63; p < 0.0001) and a negative association with CrCl (R = -0.57; p < 0.0001) were observed. CIT was higher in patients with CRF than in HCs (p < 0.0001). CIT sensitivity and specificity in detecting ACR after the 45th postoperative day were 38% and 83%, using CIT threshold observed in HCs, and 69% and 77%, respectively, using CIT threshold adjusted for CRF degree.
  
  
  CONCLUSIONS
  Adjusting CIT threshold for CRF degree almost doubled the sensitivity of CIT as a non-invasive marker of ACR in ITx recipients.
authors.affiliation: Center for Chronic Intestinal Failure, Department of Gastroenterology, Sant'Orsola-Malpighi Hospital, University of Bologna, Bologna, Italy.
authors.forename: Loris
authors.initials: L
authors.lastname: Pironi
authors.affiliation: Center for Chronic Intestinal Failure, Department of Gastroenterology, Sant'Orsola-Malpighi Hospital, University of Bologna, Bologna, Italy.
authors.forename: Mariacristina
authors.initials: M
authors.lastname: Guidetti
authors.affiliation: Transplantation Surgical Unit, Department of Organ Failure and Transplantation, Sant'Orsola-Malpighi Hospital, University of Bologna, Bologna, Italy.
authors.forename: Augusto
authors.initials: A
authors.lastname: Lauro
authors.affiliation: Transplantation Surgical Unit, Department of Organ Failure and Transplantation, Sant'Orsola-Malpighi Hospital, University of Bologna, Bologna, Italy.
authors.forename: Chiara
authors.initials: C
authors.lastname: Zanfi
authors.affiliation: Center for Chronic Intestinal Failure, Department of Gastroenterology, Sant'Orsola-Malpighi Hospital, University of Bologna, Bologna, Italy.|PhD on Medical Sciences, University of Bologna, Bologna, Italy.
authors.forename: Federica
authors.initials: F
authors.lastname: Agostini
authors.affiliation: Center for Histopathological and Molecular Diagnostic of Solid Organ Transplantation, Department of Organ Failure and Transplantation, Sant'Orsola-Malpighi Hospital, University of Bologna, Bologna, Italy.
authors.forename: Antonietta
authors.initials: A
authors.lastname: D'Errico
authors.affiliation: Center for Histopathological and Molecular Diagnostic of Solid Organ Transplantation, Department of Organ Failure and Transplantation, Sant'Orsola-Malpighi Hospital, University of Bologna, Bologna, Italy.
authors.forename: Annalisa
authors.initials: A
authors.lastname: Altimari
authors.affiliation: Transplantation Surgical Unit, Department of Organ Failure and Transplantation, Sant'Orsola-Malpighi Hospital, University of Bologna, Bologna, Italy.
authors.forename: Antonio D
authors.initials: AD
authors.lastname: Pinna
mesh_terms: D000328:Adult; D015415:Biomarkers / Q000097:blood*; D016022:Case-Control Studies; D002956:Citrulline / Q000097:blood*; D005260:Female; D005500:Follow-Up Studies; D006084:Graft Rejection / Q000097:blood / Q000175:diagnosis*; D006085:Graft Survival; D006801:Humans; D007410:Intestinal Diseases / Q000097:blood / Q000150:complications / Q000601:surgery*; D007421:Intestine, Small / Q000637:transplantation*; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications; D011379:Prognosis; D011446:Prospective Studies; D051437:Renal Insufficiency / Q000097:blood / Q000175:diagnosis*; D012307:Risk Factors; D013997:Time Factors; D055815:Young Adult
chemical_list: D015415:Biomarkers; D002956:Citrulline
keywords: acute cellular rejection; intestinal transplantation; plasma citrulline