title: Evaluation of Helicobacter species in inflammatory bowel disease.
abstract: BACKGROUND
  Bacteria have been implicated in the pathogenesis of inflammatory bowel disease. Helicobacter species have been shown to cause colitis in animal models and have been identified in human diarrhoeal illness and Crohn's disease.
  
  
  OBJECTIVE
  To determine whether Helicobacter species are present in human inflammatory bowel disease tissue.
  
  
  METHODS
  Thirty patients undergoing colonoscopy for clinical reasons were studied. Nine had Crohn's disease, 11 had ulcerative colitis and 10 had histologically normal colons. Tissue was snap-frozen at -70 degrees C. DNA was extracted and examined by five different polymerase chain reaction (PCR) assays that were either genus or species specific for Helicobacter.
  
  
  RESULTS
  Analyses of colonic biopsies by two Helicobacter genus-specific PCR assays, two H. pylori-specific assays and a PCR assay designed to amplify fragments of 'H. heilmannii'-like organisms demonstrated that product was not generated by any test. Internal control PCR demonstrated that PCR results for the five assays were not negative due to the presence of residual substances inhibitory to PCR.
  
  
  CONCLUSIONS
  Helicobacter species were not identified in this study, using multiple PCRs to eliminate the problems of non-specific cross-reaction. This suggests that Helicobacter species do not play a role in the pathogenesis of inflammatory bowel disease.
authors.affiliation: St Mark's Hospital, Harrow, UK.
authors.forename: S J
authors.initials: SJ
authors.lastname: Bell
authors.forename: S A
authors.initials: SA
authors.lastname: Chisholm
authors.forename: R J
authors.initials: RJ
authors.lastname: Owen
authors.forename: S P
authors.initials: SP
authors.lastname: Borriello
authors.forename: M A
authors.initials: MA
authors.lastname: Kamm
mesh_terms: D000328:Adult; D000368:Aged; D004269:DNA, Bacterial / Q000235:genetics*; D005260:Female; D016998:Helicobacter / Q000235:genetics*; D016481:Helicobacter Infections / Q000235:genetics*; D016480:Helicobacter pylori / Q000235:genetics; D006801:Humans; D015212:Inflammatory Bowel Diseases / Q000382:microbiology*; D008297:Male; D008875:Middle Aged; D016133:Polymerase Chain Reaction / Q000379:methods
chemical_list: D004269:DNA, Bacterial