title: Magnetic resonance imaging to distinguish the type and severity of pediatric inflammatory bowel diseases.
abstract: BACKGROUND
  The distinction between ulcerative colitis and Crohn's disease is important, because treatment options and clinical course may vary. Magnetic resonance imaging (MRI) allows noninvasive transmural assessment of the intestine and may facilitate differentiation of ulcerative colitis from Crohn's disease. The objective of this prospective study was to determine whether MRI differentiates Crohn's disease from ulcerative colitis in children as effectively as colonoscopy with mucosal biopsies.
  
  
  METHODS
  Fifteen patients underwent colonoscopy with biopsies followed by abdominal MRI. The MRI diagnosis, determined by two radiologists independently completing a standardized form was compared with the gastroenterologic diagnosis.
  
  
  RESULTS
  After colonoscopy and review of histology, Crohn's disease was diagnosed in nine patients, ulcerative colitis in five, and indeterminate colitis in one, who was excluded from study. Agreement of the MRI diagnosis with the gastroenterologic diagnosis was 4 of 4 (100%) for ulcerative colitis, 4 of 10 (40%) for Crohn's disease considering both radiologists, and 5 of 10 (50%) for Crohn's disease for each radiologist individually. Percentage of enhancement by MRI did not correlate with the severity of inflammation determined at endoscopy among the patients with Crohn's disease (r = -0.3, P = 0.366). There was agreement on severity of inflammation in three of four patients with ulcerative colitis.
  
  
  CONCLUSIONS
  Current MRI interpretation of inflammatory bowel disease did not adequately recognize Crohn's disease in children. Therefore, colonoscopy with biopsy remains the most accurate tool for determining the type and severity of inflammatory bowel disease in children and adolescents.
authors.affiliation: Division of Gastroenterology and Nutrition, The Hospital for Sick Children, Toronto, Ontario, Canada.
authors.forename: C A
authors.initials: CA
authors.lastname: Durno
authors.forename: P
authors.initials: P
authors.lastname: Sherman
authors.forename: T
authors.initials: T
authors.lastname: Williams
authors.forename: B
authors.initials: B
authors.lastname: Shuckett
authors.forename: A
authors.initials: A
authors.lastname: Dupuis
authors.forename: A M
authors.initials: AM
authors.lastname: Griffiths
mesh_terms: D000293:Adolescent; D001706:Biopsy; D002648:Child; D003093:Colitis, Ulcerative / Q000175:diagnosis / Q000473:pathology; D003106:Colon / Q000473:pathology; D003113:Colonoscopy; D003424:Crohn Disease / Q000175:diagnosis / Q000473:pathology; D003937:Diagnosis, Differential; D006801:Humans; D007082:Ileum / Q000473:pathology; D015212:Inflammatory Bowel Diseases / Q000175:diagnosis* / Q000473:pathology; D007413:Intestinal Mucosa / Q000473:pathology; D008279:Magnetic Resonance Imaging; D011446:Prospective Studies