title: Intestinal permeability in patients with irritable bowel syndrome after a waterborne outbreak of acute gastroenteritis in Walkerton, Ontario.
abstract: BACKGROUND
  Post-infectious irritable bowel syndrome is a common clinical phenomenon of uncertain aetiology.
  
  
  OBJECTIVE
  To test the association between intestinal permeability and irritable bowel syndrome symptoms 2 years after a large waterborne outbreak of bacterial gastroenteritis.
  
  
  METHODS
  Consecutive adults with Rome I irritable bowel syndrome and controls without irritable bowel syndrome attending a community clinic were enrolled. Intestinal permeability was measured as the ratio of fractional urinary excretions of lactulose and mannitol, and compared among cases vs. controls and predictors of abnormal intestinal permeability were assessed.
  
  
  RESULTS
  A total of 218 subjects (132 irritable bowel syndrome cases and 86 non-irritable bowel syndrome controls) completed the study protocol. About 27 (12%) had been diagnosed with the irritable bowel syndrome before the outbreak and 115 (53%) had been ill during the outbreak. Lactulose-mannitol ratios were increased among cases vs. controls (Mann-Whitney mean rank 118.8 vs. 95.3, P = 0.007), and cases were more likely to have a ratio >0.020 (P = 0.007). Among cases, those with increased intestinal permeability were more likely to report increased stool frequency. Both irritable bowel syndrome symptoms and male gender, but not diarrhoeal illness during the outbreak, were significant predictors of abnormal permeability.
  
  
  CONCLUSIONS
  Irritable bowel syndrome symptoms are associated with a subtle increase in intestinal permeability irrespective of prior gastroenteritis. This may improve understanding of the aetiology of both sporadic and post-infectious irritable bowel syndrome.
authors.affiliation: Department of Medicine, Division of Gastroenterology, McMaster University, Hamilton, Ontario, Canada. marshllj@mcmaster.ca
authors.forename: J K
authors.initials: JK
authors.lastname: Marshall
authors.forename: M
authors.initials: M
authors.lastname: Thabane
authors.forename: A X
authors.initials: AX
authors.lastname: Garg
authors.forename: W
authors.initials: W
authors.lastname: Clark
authors.forename: J
authors.initials: J
authors.lastname: Meddings
authors.forename: S M
authors.initials: SM
authors.lastname: Collins
mesh_terms: D000208:Acute Disease; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001424:Bacterial Infections / Q000453:epidemiology; D004196:Disease Outbreaks; D005260:Female; D005759:Gastroenteritis / Q000150:complications* / Q000453:epidemiology; D006801:Humans; D043183:Irritable Bowel Syndrome / Q000378:metabolism*; D007792:Lactulose / Q000378:metabolism; D008297:Male; D008353:Mannitol / Q000378:metabolism; D008875:Middle Aged; D009864:Ontario / Q000453:epidemiology; D010539:Permeability
chemical_list: D008353:Mannitol; D007792:Lactulose