Interventional study of a group of patients with an inflammatory bowel disease (IBD; Crohn's disease (CD) or ulcerative colitis (UC)) to identify predictive and prognostic biomarkers of natural history and response to biotherapies.

Percentage of primary responders who haven't lost response to biotherapies during follow-up (anti-TNF, ustekinumab, vedolizumab).

Response to treatment will be evaluated using objective criteria for measuring intestinal inflammation: endoscopic remission (endoscopic biopsy and surgical specimens), radiological (MRI), and / or biological (CRP, fecal calprotectin) .

Response to therapy rates will be correlated with genomic, epigenomic, and microbiota data stratified by major environmental factors (nutrition, tobacco, physical activity).

Inclusion Criteria:

• Age>=18 years
• Patients with an established diagnosis of CD or UC (clinical, biological, radiological, endoscopic or histologic criteria)
• Patients >=45 kg
• Affiliated member of the Social Security system

Exclusion Criteria:

• Patients with an undetermined colitis

• Patients with a non established diagnosis of CD

• Women of childbearing age without a method of contraception

• Persons covered by articles L. 1121-5, L. 1121-7 and L1121-8 of the Public Health Code

• Pregnant women, breastfeeding women

  -- Age < 18 years

• Persons under legal protection

• Person who does not have the capacity to consent

• Persons under the age of 18 years who are deprived of their liberty by decision of a judicial or administrative authority (articles L. 3212-1 and L. 3213-1).