BACKGROUND & AIMS: Crohn's disease (CD) diagnosed in pediatric patients has been 
reported to have a more aggressive phenotype and course, with a greater 
prevalence of upper gastrointestinal involvement, than in adults. However, 
studies have not accounted for differences in diagnostic tests. We aimed to 
discern whether, in fact, CD diagnosed in childhood has a different outcome than 
CD diagnosed in adults.
METHODS: We performed comprehensive medical chart reviews of 571 patients with 
CD (451 with complete data) who were followed in a single referral inflammatory 
bowel disease clinic in Winnipeg, Canada, from 1993-2012. For specific time 
intervals, we determined types and numbers of imaging studies performed and 
parameters of disease phenotype, including age at diagnosis according to the 
Montreal classification (A1 diagnosed <17 years of age, A2 diagnosed 17-40 
years, and A3 diagnosed >40 years).
RESULTS: Within 1 year of diagnosis, a higher proportion of A1 patients had 
upper gastrointestinal involvement and ileocolonic (L3) disease than A2 or A3 
patients. These differences could be partly accounted for by the diagnostic 
tests performed during this time period. Although A1 patients underwent more 
extensive imaging studies, they had a lower prevalence of complicated disease, 
particularly compared with A3 patients. After a median follow-up period of 11.1 
years, complicated disease behavior (B2 [structuring] or B3 [penetrating]) was 
similar among the 3 groups. Nonetheless, at the end of the study period, rates 
of inflammatory bowel disease-related abdominal surgery were significantly lower 
for A1 than A2 patients (odds ratio, 0.63; 95% confidence interval, 0.41-0.98) 
but not for A3 patients (odds ratio, 0.71; 95% confidence interval, 0.40-1.27).
CONCLUSIONS: On the basis of a database analysis of different age groups of 
patients with CD, studies of disease phenotypes among different cohorts should 
account for different patterns of diagnostic imaging evaluation. Our data show 
that although children are at increased risk of panenteric disease, they are not 
more likely to have more complicated disease or undergo surgery than adults.