title: Presentation and progression of childhood-onset inflammatory bowel disease in Northern Stockholm County.
abstract: BACKGROUND
  Some studies have suggested that childhood-onset inflammatory bowel disease (IBD) is characterized by extensive intestinal involvement and rapid progression to complications. Here, we report the presentation and progression of patients diagnosed with IBD during childhood in a population-based cohort from northern Stockholm County.
  
  
  METHODS
  Medical records for all 280 patients diagnosed in the period 1990-2007 with childhood-onset IBD in northern Stockholm County were followed until 2011 (median follow-up time, 8.8 yr). Disease phenotypes were classified according to the Paris pediatric IBD classification.
  
  
  RESULTS
  Among the 74 patients with ulcerative colitis, 72% presented with pancolitis. Among the 200 patients with Crohn's disease (CD), 75% presented with colitis. Complicated disease behavior was observed in 18% of patients with CD by end of follow-up. Extension of the disease territory was observed in 22% of patients with ulcerative colitis and 15% of patients with CD. The cumulative risk of intra-abdominal surgery after 10 years was 8% (95% confidence interval, 4%-20%) for ulcerative colitis and 22% (95% confidence interval, 15%-28%) for patients with CD. Nonmucosal healing at 1 year was associated with a complicated disease course in patients with CD (hazard ratio = 14.56; 95% confidence interval, 1.79-118.68; P = 0.01).
  
  
  CONCLUSIONS
  Patients with childhood-onset IBD were characterized by extensive colitis that was relatively stable over time and associated with a relatively low risk of complications and abdominal surgery. Our findings confirm the more extensive disease location in pediatric IBD but did not identify the proposed dynamic and aggressive nature of the childhood-onset phenotype. The association of nonmucosal healing with a complicated disease course suggests that endoscopy should guide treatment intensity in childhood-onset CD.
authors.affiliation: *Department of Women's and Children's Health, Astrid Lindgren Children's Hospital, Karolinska University Hospital, Karolinska Institutet, Stockholm, Sweden; Departments of †Oncology-Pathology and ‡Medicine, Karolinska University Hospital, Karolinska Institutet, Stockholm, Sweden; §Clinical Epidemiology Unit, Department of Medicine, Karolinska Institutet, Stockholm, Sweden; ‖Clinical Epidemiology and Biostatistics, Örebro University Hospital and Örebro University, Örebro, Sweden; and ¶Department of Epidemiology and Public Health, University College London, London, United Kingdom.
authors.forename: Petter
authors.initials: P
authors.lastname: Malmborg
authors.forename: Lena
authors.initials: L
authors.lastname: Grahnquist
authors.forename: Maja
authors.initials: M
authors.lastname: Ideström
authors.forename: Johan
authors.initials: J
authors.lastname: Lindholm
authors.forename: Ragnar
authors.initials: R
authors.lastname: Befrits
authors.forename: Jan
authors.initials: J
authors.lastname: Björk
authors.forename: Scott
authors.initials: S
authors.lastname: Montgomery
authors.forename: Hans
authors.initials: H
authors.lastname: Hildebrand
mesh_terms: D000293:Adolescent; D017668:Age of Onset; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D018450:Disease Progression; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D007223:Infant; D015212:Inflammatory Bowel Diseases / Q000175:diagnosis* / Q000453:epidemiology; D008297:Male; D008499:Medical Records; D010641:Phenotype; D011379:Prognosis; D012307:Risk Factors; D012720:Severity of Illness Index; D013548:Sweden / Q000453:epidemiology; D013997:Time Factors