title: Predictive value of serologic markers in a population-based Norwegian cohort with inflammatory bowel disease.
abstract: BACKGROUND
  Perinuclear antineutrophil cytoplasmic antibodies (pANCA) and anti-Saccharomyces cerevisiae antibodies (ASCA) are proposed to be specific markers for ulcerative colitis (UC) and Crohn's disease (CD). Their prevalence and relationship to disease phenotype and outcome in unselected cohorts of patients with inflammatory bowel disease (IBD), however, is largely unclear. We studied the prevalence of these serologic markers in a population-based IBD cohort 10 years after diagnosis, and examined whether their presence could be related to distinct subgroups and outcome of disease.
  
  
  METHODS
  Of 685 living IBD patients, 620 met for a 10-year follow-up, of whom 526 (UC, n = 357 and CD, n = 169) participated in this study.
  
  
  RESULTS
  Twenty-seven percent (n = 46) of CD patients were ASCA-positive and 31% (n = 109) of UC patients were pANCA-positive. Positive ASCA was more frequent in CD patients with stricturing (P = 0.003) or penetrating (P = 0.012) complications than in those with inflammatory behavior at diagnosis. Moreover, the presence of ASCA was associated with an at least twice higher risk of evolving more severe disease behavior during follow-up (P < 0.001). In UC, pANCA expression was related to female gender (P = 0.005) and the use of azathioprine (P < 0.001), and in CD, to colon-limited disease and age >/=40 years at diagnosis (P = 0.009 and P = 0.001, respectively).
  
  
  CONCLUSIONS
  The prevalence of ASCA in CD and pANCA in UC appears markedly lower than in referral-based populations. Even with the low prevalence, our study gives further support to the role of ASCA and pANCA as markers for distinct phenotype and outcome of disease.
authors.affiliation: Department of Gastroenterology, Ullevål University Hospital, Oslo, Norway. i.c.solberg@medisin.uio.no
authors.forename: Inger Camilla
authors.initials: IC
authors.lastname: Solberg
authors.forename: Idar
authors.initials: I
authors.lastname: Lygren
authors.forename: Milada
authors.initials: M
authors.lastname: Cvancarova
authors.forename: Jørgen
authors.initials: J
authors.lastname: Jahnsen
authors.forename: Njaal
authors.initials: N
authors.lastname: Stray
authors.forename: Jostein
authors.initials: J
authors.lastname: Sauar
authors.forename: Stefan
authors.initials: S
authors.lastname: Schreiber
authors.forename: Bjørn
authors.initials: B
authors.lastname: Moum
authors.forename: Morten H
authors.initials: MH
authors.lastname: Vatn
mesh_terms: D000328:Adult; D019268:Antibodies, Antineutrophil Cytoplasmic / Q000097:blood* / Q000276:immunology; D015415:Biomarkers / Q000097:blood*; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015212:Inflammatory Bowel Diseases / Q000097:blood* / Q000175:diagnosis / Q000453:epidemiology; D008297:Male; D009664:Norway / Q000453:epidemiology; D011237:Predictive Value of Tests; D015995:Prevalence; D011446:Prospective Studies; D012720:Severity of Illness Index; D013997:Time Factors
chemical_list: D019268:Antibodies, Antineutrophil Cytoplasmic; D015415:Biomarkers