Impact of Anti-cytomegalovirus Treatment in the Management of Relapsing Ulcerative Colitis Requiring Vedolizumab Therapy

Inclusion Criteria: * Patient with moderate to severe active Ulcerative Colitis (UC) defined by a Mayo score greater than 5 * Patient with an inflammatory outbreak of Ulcerative Colitis (UC) : * without anti-TNF * under anti-TNF (infliximab, adalimumab, golimumab) after induction (no primary response) or clinical recurrence (secondary failure). * Having rectosigmoidoscopy with an endoscopic Mayo score≥ 2 with 2 biopsies of the inflammatory tissue * Presence of a CytoMegaloVirus (CMV) infection in the inflammatory tissue (viral load greater than 5 IU / 100000 cells by qPCR) * Patient with a negative pre-treatment assessment including HIV, HBV, HCV, HCV serology, a negative quantiferon or a history of tuberculosis preventive treatment adapted by Rifinah or Rimifon * Signed informed consent Exclusion Criteria: * Patient with severe acute colitis * Patient treated by ciclosporin or Prograf * Patient with Human Immunodeficiency Virus (HIV)+, hepatitis B, hepatitis C, tuberculosis * Clostridium difficile infection. * Patient with intolerance or contraindications to current therapy * Pregnant or starts breastfeeding * Patient who received a live vaccine in the month preceding the study * Patients with severe renal insufficiency defined by creatinine clearance \<30ml/minute, or hemodialysed