Inclusion Criteria:  Patients with histologically confirmed diagnosis of Crohn disease (CD) or Ulcerative colitis (UC) in the last 6 months and undergoing followup colonoscopy.  Exclusion Criteria:  (a) prior proctocolectomy; (b) presence of IBD extraintestinal manifestation; (c) treatment with antibiotics in the last 60 days; (d) extensive surgical resection; (e) presence of stoma.