title: Association of Mycobacterium avium subspecies paratuberculosis with Crohn Disease in pediatric patients.
abstract: OBJECTIVE
  The aim of the present study was to determine the prevalence of Mycobacterium avium subsp paratuberculosis (MAP) DNA in intestinal biopsies from pediatric patients with granulomatous Crohn disease (CD) or ulcerative colitis (UC), and matched control subjects without inflammatory bowel disease (IBD).
  
  
  METHODS
  DNA was extracted from formalin-fixed paraffin-embedded colonic and ileal biopsies from patients with CD (n = 22) or UC (n = 20), and from controls without IBD (n = 21). IS900 nested polymerase chain reaction was performed in triplicate to determine the presence of MAP-specific DNA.
  
  
  RESULTS
  In mucosal biopsies from terminal ileum, IS900 amplicons were detected in 1 of 19 (5.2%) control subjects, 1 of 20 (5%) patients with UC, and 7 of 20 (35%) patients with CD (P < 0.05 vs controls, odds ratio 9.6). In colonic biopsies, IS900 amplicons were detected in 0 of 19 control subjects, 1 of 19 (5.2%) patients with UC, and 5 of 19 (26.3%) patients with CD (P < 0.05 vs controls, odds ratio 14.8). In patients with CD, there was no correlation between disease activity and the presence of IS900.
  
  
  CONCLUSIONS
  Our technique enabled sensitive and specific detection of MAP DNA in archival endoscopic biopsy specimens. Although MAP-specific DNA can be detected in about 5% of intestinal biopsies from children with UC or controls without IBD, its presence was significantly associated with pediatric granulomatous CD, being particularly prevalent in ileal tissue. This easily defined clinical subset of patients may be useful for additional studies to determine the role of MAP in CD.
authors.affiliation: Department of Medicine, Division of Gastroenterology, Canada.
authors.forename: Adrienne
authors.initials: A
authors.lastname: Lee
authors.forename: Tanya A
authors.initials: TA
authors.lastname: Griffiths
authors.forename: Rohan S
authors.initials: RS
authors.lastname: Parab
authors.forename: Robin K
authors.initials: RK
authors.lastname: King
authors.forename: Marla C
authors.initials: MC
authors.lastname: Dubinsky
authors.forename: Stefan J
authors.initials: SJ
authors.lastname: Urbanski
authors.forename: Iwona
authors.initials: I
authors.lastname: Wrobel
authors.forename: Kevin P
authors.initials: KP
authors.lastname: Rioux
mesh_terms: D000293:Adolescent; D001706:Biopsy; D016022:Case-Control Studies; D002648:Child; D002675:Child, Preschool; D003093:Colitis, Ulcerative / Q000382:microbiology; D003424:Crohn Disease / Q000150:complications / Q000382:microbiology*; D004269:DNA, Bacterial / Q000032:analysis; D005260:Female; D006801:Humans; D007082:Ileum / Q000382:microbiology / Q000473:pathology; D008297:Male; D009164:Mycobacterium Infections / Q000150:complications / Q000453:epidemiology / Q000382:microbiology*; D016927:Mycobacterium avium subsp. paratuberculosis / Q000302:isolation & purification*; D016133:Polymerase Chain Reaction; D015995:Prevalence
chemical_list: D004269:DNA, Bacterial