1. IRCCS-Azienda Ospedaliero, Universitaria di Bologna, 40138 Bologna, Italy
2. Department of Medical Sciences, Division of Gastroenterology and Hepatology, A.O. Città della Salute e della Scienza di Torino, University of Turin, 10124 Turin, Italy
3. Department of Medical and Surgical Sciences, Alma Mater University of Bologna, 40138 Bologna, Italy