1. Division of Gastroenterology and Digestive Endoscopy, Department of Medical Sciences, Central Hospital – Azienda Ospedaliera, Taranto
2. Department of Medical and Surgical Sciences, University of Bologna
3. Gastroenterology Unit, IRCCS Azienda Ospedaliero-Universitaria di Bologna
4. Esophagus and Stomach Organic Diseases Unit, IRCCS Azienda Ospedaliero-Universitaria di Bologna, Bologna, Italy