Crohn's disease (CD) and ulcerative colitis (UC) are chronic Inflammatory Bowel Disease (IBD) and may affect all segments of the digestive tract. These are diseases of multifactorial origin in which environmental and genetic factors are predominant.The EPIMAD registry, the world's largest epidemiological register for IBD, identifying all incident cases in the four departments of the North West of France showed between 1988 and 2007, an increase in the annual incidence of MC 71 % (6.5 / 105 (1988-1990) 11.1 / 105 (2006-2007) p \<0.0001) in the age group 10-19 years. At the same time, the annual incidence of UC decreased 4.3 / 3.5 105 inhabitants / 105 inhabitants (20%), with phenotypic presentation remained stable. The increase in the incidence of CD will contribute to increase its weight in the health system, particularly in the pediatric CD frequently associated with an aggressive phenotype causing specific complications such as malnutrition, pubertal delay or thrive. These complications have a important impact on the quality of life with a long-term risk of functional disability. They may be associated with increased mortality. Immunosuppressants (azathioprine, methotrexate) have been used in pediatric forms only from the 90s and anti-TNF antibodies (infliximab and adalimumab), until the 2000s. These new therapeutic classes have profoundly changed the management of pediatric IBD. Although there is little data on the impact of these new treatments, early introduction of immunosuppressive and anti-TNFs seems to influence the natural history of IBD diagnosed in pediatric age. Anti-TNFs appear to be associated with more frequent and deeper remission. With the advent of these new treatment, new therapeutic targets such as endoscopic mucosal healing and more recently the deep remission combining clinical remission, biological and endoscopic, appears. However there is no data in the general population assessing the impact of new treatments and new therapeutic strategies in the pediatric population. Potential risks associated with the increasing use and early use of biological treatments in this particular population remain to be determined in the general population.
The main hypothesis of this study is that changes in therapeutic strategies in IBD diagnosed before 17 yeras old could influence the cumulative incidence of surgical resection and complications specific to this population as failure to thrive and delayed puberty, insertion socio-professional, the extension of the disease, hospitalization rates, and the rate of cancer.
