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.
