I. INTRODUCTION Crohn 's disease is a chronic inflammatory process characterized by recurrent inflammatory states. In the natural history of this disease, there is an alternation of flare-ups (relapse phases) and of phases in which the disease is almost or completely asymptomatic (remission phases). According to various case studies, approximately 25% to 50% of patients relapse per year and approximately 70% relapse within 2 years (1-5). Approximately 70% of patients undergo surgery at least once during their lives for Crohn 's disease complications (6-10). After complete resection of all the diseased gut, the lesion reappears endoscopically (recurrence) within I year in 70% to 90% of patients, and, within 3 years, approximately 90% of patients are symptomatic (11,12).