MOlecular BIomarkers and Adherent and Invasive Escherichia Coli (AIEC) Detection Study In Crohn's Disease Patients

350 Crohn's disease patients will be included in the study, targeting 300 evaluable patients. An interim analysis will be performed after 50% of the evaluable patients are recruited. The primary objective is to evaluate the relation between non-invasive biomarkers (host immunological variables and metagenomic analysis in stools) and AIEC detection in biopsies taken during an endoscopy, in order to develop a predictive algorithm of AIEC carriage. The secondary objectives are: * Validation of the AIEC detection algorithm using qPCR technology. * Assessment of the correlation between the presence of AIEC and the endoscopic and clinical evaluations of the disease (CDEIS, SES-CD, Harvey-Bradshaw Index and Crohn's Disease Activity Index). * Development and validation of a non-invasive qPCR based diagnostic of Mucosal Healing in CD patients. * Collection of biological samples associated with all clinical and biological data from CD patients.