1. Department of Clinical and Experimental Medicine, University of Messina, 98100 Messina, Italy
2. Digestive Endoscopy Unit, University of Verona, 37100 Verona, Italy
3. Gastroenterology and Endoscopy Unit, S. Elia-Raimondi Hospital, 93100 Caltanissetta, Italy
4. Gastroenterology and Endoscopy Unit, Fondazione Istituto San Raffaele Giglio, 90015 Cefalù, Italy
5. Human Pathology of Adult and Child Department, University of Messina, 98100 Messina, Italy
6. Gastroenterology Unit, Department of Medical and Surgical Sciences, University of Foggia, 71100 Foggia, Italy
7. Division of Digestive Diseases, University of Cincinnati, Cincinnati, OH 45201, USA
8. Gastroenterology Unit, National Institute of Gastroenterology—IRCCS “Saverio de Bellis” Castellana Grotte, 70013 Castellana Grotte, Italy