Ileovesical fistula is a rare inaugural complication of Crohn disease. Current approaches associate antibiotics, total parenteral nutrition and various combinations of immunomodulatory agents. However, only a minority of fistulas subside under conventional treatment, as most of them ultimately require complex surgery to excise and close the structures involved. We report the case of a 31-year-old patient successfully treated by targeting the local production of tumour necrosis factor alpha with infliximab.