Gut check: new study seeks blood test for IBD by comparing patients and healthy volunteers

Copied word for word from the study's registry entry, so the wording is the study team's rather than ours.

Inclusion Criteria: General criteria: * Male or female ≥ 18 years old * Able to follow the instructions of the study * Having signed an informed consent Specific for Crohn cohort: * A confirmed diagnosis of IBD * Rectal or colonic or ileocolic involvement * Patients with CD presenting inflammatory flare and disease extent in the colon or ileocolic region with: * A clinical activity defined by an average of four or more instances of very soft or liquid stools daily or an abdominal pain score of 2 or more OR a CDAI (CD Activity Index) ≥ 220 OR a Harvey-Bradshaw Index \> 8 OR a faecal calprotectin ≥ 250 µg/g And * A endoscopic activity defined by a SES-CD (Simple Endoscopic Score for Crohn Disease) ≥ 6 or a CDEIS (CD Endoscopic Index score) ≥ 7 * Patients with UC presenting inflammatory flare with: A clinical activity defined by a modified Mayo score ≥ 3 OR a Simple Clinical Colitis Activity Index ≥5 OR Patient Reported Outcome (PRO2) ≥ 4 with a subscore of rectal bleeding ≥1 OR a faecal calprotectin ≥ 250 µg/g AND An endoscopic activity defined by a Mayo endoscopic sub-score ≥ 2 Specific for Control cohort: Patient with no colonic lesion(s) visible during the endoscopical examination (neither Crohn's nor other colitis nor cancer) Exclusion Criteria: General criteria: * Commercial Pharmaceutical probiotic administration within the previous month * Treatment with antibiotics (whatever the route of administration) within last 3 months * Non-remission Cancer or in remission for less than 6 months * Any contraindication to colonoscopy and/or biopsy, left to PI discretion * Under guardianship or judiciable protection * Pregnant or breastfeeding women * Currently participating or having participated in the last 3 months to a clinical study with investigational medicine or food supplement Specific for Crohn cohort: * Crohn disease localized only in Ileum * Inflammatory colon pathology other than Crohn's (infectious, drug-induced,…)