title: Development of Fibrosis in Acute and Longstanding Ulcerative Colitis.
abstract: BACKGROUND
  Intestinal fibrosis is a process driven by chronic inflammation leading to increased presence of myofibroblasts and collagen deposition. Although strictures are rarely seen in ulcerative colitis [UC], longstanding disease is believed to cause fibrosis resulting in altered bowel function.
  
  
  METHODS
  The presence of fibrosis was studied in colectomy specimens from patients with recent-onset UC refractory to medical treatment [n = 13] and longstanding UC [n = 16], and colon cancer patients without UC [n = 7] as controls. Severity of inflammation was scored according to the Geboes score on haematoxylin and eosin stainings. Immunohistochemistry was performed to detect α-smooth muscle actin, fibronectin and collagen I and III.
  
  
  RESULTS
  Colectomy specimens from patients with acute UC showed significantly more inflammation than those with longstanding disease [19 vs 9 points, p = 0.01]. Both acute and longstanding UC showed a thicker muscularis mucosa than controls [0.10 vs 0.10 vs 0.05 mm, respectively, p = 0.019]. An increase in collagen I and III deposition in the mucosa was observed in UC compared with controls (40% [30-75] vs 25% [10-25], p = 0.033), but this did not differ significantly among acute and longstanding UC patients.
  
  
  CONCLUSIONS
  Collagen deposition is enhanced in UC compared with controls. However, UC collagen deposition does not increase significantly over time and does not seem to aggravate the entire fibrotic process.
authors.affiliation: Department of Gastroenterology and Hepatology, Academic Medical Center, Amsterdam, The Netherlands Tytgat Institute for Liver and Intestinal Research, Academic Medical Center, Amsterdam, The Netherlands.
authors.forename: Jessica R
authors.initials: JR
authors.lastname: de Bruyn
authors.affiliation: Department of Pathology, Academic Medical Center, Amsterdam, The Netherlands.
authors.forename: Sybren L
authors.initials: SL
authors.lastname: Meijer
authors.affiliation: Department of Gastroenterology and Hepatology, Academic Medical Center, Amsterdam, The Netherlands Tytgat Institute for Liver and Intestinal Research, Academic Medical Center, Amsterdam, The Netherlands.
authors.forename: Manon E
authors.initials: ME
authors.lastname: Wildenberg
authors.affiliation: Department of Surgery, Academic Medical Center, Amsterdam, The Netherlands.
authors.forename: Willem A
authors.initials: WA
authors.lastname: Bemelman
authors.affiliation: Department of Gastroenterology and Hepatology, Academic Medical Center, Amsterdam, The Netherlands Tytgat Institute for Liver and Intestinal Research, Academic Medical Center, Amsterdam, The Netherlands.
authors.forename: Gijs R
authors.initials: GR
authors.lastname: van den Brink
authors.affiliation: Department of Gastroenterology and Hepatology, Academic Medical Center, Amsterdam, The Netherlands Tytgat Institute for Liver and Intestinal Research, Academic Medical Center, Amsterdam, The Netherlands g.dhaens@amc.uva.nl.
authors.forename: Geert R
authors.initials: GR
authors.lastname: D'Haens
mesh_terms: D000208:Acute Disease; D000328:Adult; D000368:Aged; D015415:Biomarkers / Q000378:metabolism; D016022:Case-Control Studies; D002908:Chronic Disease; D003082:Colectomy; D003093:Colitis, Ulcerative / Q000378:metabolism / Q000473:pathology* / Q000601:surgery; D003106:Colon / Q000378:metabolism / Q000473:pathology* / Q000601:surgery; D003110:Colonic Neoplasms / Q000378:metabolism / Q000473:pathology; D018450:Disease Progression; D005355:Fibrosis; D006801:Humans; D007150:Immunohistochemistry; D007413:Intestinal Mucosa / Q000378:metabolism / Q000473:pathology*; D008875:Middle Aged; D012189:Retrospective Studies; D012720:Severity of Illness Index
chemical_list: D015415:Biomarkers
keywords: Ulcerative colitis; fibrosis; pathology