title: Fasting and Postprandial Plasma Citrulline and the Correlation to Intestinal Function Evaluated by 72-Hour Metabolic Balance Studies in Short Bowel Jejunostomy Patients With Intestinal Failure.
abstract: BACKGROUND
  Fasting plasma citrulline (p-citrulline) is a marker of functional enterocyte mass. However, the optimal timing of measurement in relation to meals has yet to be clarified. Furthermore, p-citrulline has been proposed to be a surrogate marker for small bowel length and intestinal absorption parameters in short bowel syndrome patients with intestinal failure (SBS-IF).
  
  
  METHODS
  Eight patients with SBS-IF and 8 healthy controls (HCs) were given a standardized mixed test meal, and p-citrulline was measured 15 minutes before and 60, 120, and 180 minutes after completion of the meal. The patients with SBS-IF had their intestinal absorption of wet weight, energy, macronutrients, and electrolytes measured in relation to 72-hour metabolic balance studies. We investigated the possible correlations between p-citrulline and short bowel length, absorptive parameters, and the dependence on parenteral support (PS).
  
  
  RESULTS
  In the patients with SBS-IF, we found a 12% (P = .041) reduction in postprandial citrulline levels after 180 minutes. In the HCs, there was a 13% postprandial reduction at 60 minutes (P = .018). No significant correlations between fasting p-citrulline and bowel length, bowel absorptive function, or the dependence on PS were found. Even when excluding 2 patients in whom the intestinal absorption was adjacent to the intestinal insufficiency borderlines, these correlations were not significant.
  
  
  CONCLUSIONS
  Based on findings in this small study, the optimal timing of p-citrulline measurement is on fasting samples. However, p-citrulline seems insufficiently discriminative to serve as a valid biomarker of bowel length, bowel absorptive function, or dependence on PS in patients with SBS-IF.
authors.affiliation: Department of Medical Gastroenterology CA 2121, Rigshospitalet, Copenhagen, Denmark.
authors.forename: Hilde
authors.initials: H
authors.lastname: Fjermestad
authors.affiliation: Department of Medical Gastroenterology CA 2121, Rigshospitalet, Copenhagen, Denmark.
authors.forename: Mark
authors.initials: M
authors.lastname: Hvistendahl
authors.affiliation: Department of Medical Gastroenterology CA 2121, Rigshospitalet, Copenhagen, Denmark.
authors.forename: Palle Bekker
authors.initials: PB
authors.lastname: Jeppesen
mesh_terms: D000328:Adult; D000368:Aged; D002956:Citrulline / Q000097:blood*; D005215:Fasting; D005260:Female; D006801:Humans; D007422:Intestines / Q000503:physiopathology*; D007582:Jejunostomy; D008297:Male; D008875:Middle Aged; D019518:Postprandial Period; D012778:Short Bowel Syndrome / Q000097:blood* / Q000601:surgery*; D013997:Time Factors
chemical_list: D002956:Citrulline
keywords: adult; gastroenterology; life cycle; rehabilitation; research and diseases; short bowel syndrome