Rationale: Inflammatory Bowel Diseases (IBD) is a heterogeneous group of diseases regarding clinical presentation, disease course and treatment response. Pathogenesis is complex and multifactorial, based on interactions between genetic and environmental factors, gut microbiota and the immune system, leading to intestinal inflammation. As the immune reaction itself causes the intestinal damage, differences in components of this immune mediated inflammatory reaction between IBD patients might explain the heterogeneity in response to different therapy strategies. Identifying immune components that are associated to disease activity and prognosis would enable a more personalized treatment.~Objective: Determine if assessment of mucosal and serological immunological characteristics in combination with clinical indicators of disease behaviour and response to therapy can identify immune-based phenotypes with implications for prognosis and therapeutic interventions.~Study design: The study will be a longitudinal, prospective cohort study. Study population: The study population will include newly diagnosed adults fulling the diagnostic criteria for IBD. These patients will be further studied as a follow up cohort.~Intervention: Immunological analysis of extra mucosal biopsies and venous bloodsamples taken during regular ileocolonoscopy and labcontrols at initial diagnosis and during follow up.~Main study parameters/endpoints: The description of the different mucosal and serological immunological profiles at baseline and follow up in newly diagnosed IBD patients and the correlation between these different immunological profiles and clinical indicators of disease activity, disease course and response to the received therapy.~Nature and extent of the burden and risks associated with participation, benefit and group relatedness: Ileocolonoscopy with biopsies is a standard examination in patients presenting with chronic (+/- bloody) diarrhoea and in the follow up of patients with IBD. Collection of biopsies during the gastroenterological endoscopy, ie without interventions like polypectomy, is a safe procedure (bleeding, perforation <0,001). In the regular clinical practice, different endoscopists take a variable number of biopsies (4-10) from sites of interest. The intervention in this study comprises taking 4 additional biopsies on top of the regular histological biopsies for immunological examination.~Before ileocolonoscopy, patients normally receive an infusion needle for the administration of sedation (standard care). After ileocolonoscopy this needle will be used to take a venous blood sample. If this is not possible, we take a venous bloodsample during a regular labcontrol. In the follow up period, during regular endoscopies and blood checks the same additional samples will be taken.~Therefore, we believe the burden and risks for patients are minimalised.
Inflammatory Bowel Diseases (IBD) is a heterogeneous group of diseases regarding clinical presentation, disease course and treatment response. Pathogenesis is complex and multifactorial, based on interactions between genetic and environmental factors, gut microbiota and the immune system, leading to intestinal inflammation. As the immune reaction itself causes the intestinal damage, differences in components of this immune mediated inflammatory reaction between IBD patients might explain the heterogeneity in response to different therapy strategies. Identifying immune components that are associated to disease activity and prognosis would enable a more personalized treatment.