Preoperative enteral nutrition in adults with complicated Crohn's disease: Effect on disease outcomes and gut microbiota

•Preoperative exclusive enteral nutrition improved disease activity and nutritional status in adult patients with Crohn's disease referred to surgery.•Despite being malnourished, patients given exclusive enteral nutrition had similar postoperative outcomes compared with well-nourished patients.•During exclusive enteral nutrition, overall microbiota composition changed and α diversity decreased.•Exclusive enteral nutrition did not influence postoperative recurrence and gut microbiota 6 mo after surgery.