Systematic versus Endoscopy-driven Treatment with Azathioprine to Prevent Postoperative Ileal Crohn's Disease Recurrence. - Ferrante, Marc; Papamichael, Konstantinos; Duricova, Dana; D'Haens, Geert; Vermeire, Severine; Archavlis, Emmanuel; Rutgeerts, Paul; Bortlik, Martin; Mantzaris, Gerassimos; Van Assche, Gert (Journal of Crohn's & Colitis, 2015)