The purpose is to search for enterocyte-specific or non-specific molecular signature of post-operating recurrence of Crohn's disease in transcriptome (measurement of gene expression through number of mRNA copies transcribed for each gene) and in methylome.

Secondary objectives are to compare expression and methylation profiles according to:

• treatment response
• morphological (endoscopic and/or radiological) and clinical post-operating recurrence.

This aim of this study is to search for new biomarkers predictive of post-operating recurrence.

At present, there are no biomarkers predictive for post-operating recurrence and administration of a post-operating medical treatment to prevent recurrence is based on biological, endoscopic and imagery data.

Predictive biomarkers could allow the identification of patients with high risk of post-operating recurrence and administration of a systematic prophylactic post-operating treatment and at the same time avoiding the prescription of this treatment to patients with low risk of post-operating recurrence.

Inclusion Criteria:

• Patient with inflammatory bowel disease diagnosis based on clinical (abdominal pain, diarrhea and/or dysenteric syndrome, mostly muco-hemorrhagic, perianal injury, with sometimes general signs and /or systemic manifestations ), biological (inflammatory syndrome, deficiencies…), radiological (entero-MRI), endoscopic (presence of granulomatous lesions) and/or histological (epithelioid and giant cellular granuloma) data
• Patient undergoing ileocolic resection
• Patient affiliated to French social security

Exclusion Criteria:

• Patient refusing sampling
• Patient with undetermined colitis
• Patient with non-confirmed diagnosis of inflammatory bowel disease
• Patient with inflammatory bowel disease not undergoing ileocolic resection

Patients with Crohn's disease needing an ileocolic resection at CHRU Nancy.