1. Gastroenterology Unit, Rho Hospital, ASST Rhodense, Corso Europa 250, 20017 Rho (MI), Italy
2. Gastroenterology Unit, Department of Medical Sciences, University of Pavia, Pavia, Italy
3. Division of Gastroenterology, Department of Medical Sciences, University of Turin, Turin, Italy
4. Gastroenterology Unit, Rho Hospital, ASST Rhodense, Rho, Italy