title: Clinical relevance of measuring colonic permeability.
abstract: BACKGROUND
  Gastroduodenal and small intestinal permeability are increased in patients with Crohn's disease (CD) and intensive care patients. The relevance of colonic permeability has not yet been adequately investigated. The aim of this study was to investigate the clinical value of sucralose excretion as indicator for colonic permeability in these patient groups.
  
  
  METHODS
  After oral administration of four sugars and subsequent analysis of urinary excretion, gastroduodenal and intestinal permeability were calculated from saccharose excretion and lactulose/mannitol (L/M) ratio over 5 h, and sucralose excretion from 5 to 26 h in 100 healthy controls, 29 CD and 35 patients after coronary surgery (CABG).
  
  
  RESULTS
  In controls, sucralose excretion was highly variable (0.67+/-0.92%) and not related to small intestinal permeability. In CD and CABG, L/M ratio was increased (0.054+/-0.060; 0.323+/-0.253 vs. 0.018+/-0.001 in controls). Sucralose excretion was increased in 77% of CABG but only in 7% of CD. There was an association between gastroduodenal and intestinal permeability in CD and CABG (r=0.72, and r=0.51), but sucralose excretion was not related to either one of these two parameters. Other than a weak association between sucralose and length of stay in intensive care in CABG patients (P=0.099), sucralose excretion was not related to clinical outcome.
  
  
  CONCLUSIONS
  The proposed cut-off for normal sucralose excretion is 2.11%, but its high variability and lack of association to gastrointestinal permeability or clinical outcome leave it open, if it can provide information beyond established permeability tests.
authors.affiliation: Charité University Clinic, Berlin, Germany. verena.haas@charite.de
authors.forename: V
authors.initials: V
authors.lastname: Haas
authors.forename: C
authors.initials: C
authors.lastname: Büning
authors.forename: S
authors.initials: S
authors.lastname: Buhner
authors.forename: C
authors.initials: C
authors.lastname: von Heymann
authors.forename: L
authors.initials: L
authors.lastname: Valentini
authors.forename: H
authors.initials: H
authors.lastname: Lochs
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D016022:Case-Control Studies; D003106:Colon / Q000378:metabolism*; D003424:Crohn Disease / Q000652:urine*; D005260:Female; D005765:Gastrointestinal Agents / Q000652:urine; D006801:Humans; D007421:Intestine, Small / Q000378:metabolism*; D007792:Lactulose / Q000652:urine; D008297:Male; D008353:Mannitol / Q000652:urine; D008875:Middle Aged; D010539:Permeability; D013395:Sucrose / Q000652:urine; D013549:Sweetening Agents / Q000378:metabolism; D055815:Young Adult
chemical_list: D005765:Gastrointestinal Agents; D013549:Sweetening Agents; D008353:Mannitol; D007792:Lactulose; D013395:Sucrose