1. Department of Biomedical Sciences, Humanitas University, 20089 Rozzano, Italy
2. Digestive Endoscopy Unit, Department of Endoscopy, Humanitas Research Hospital, IRCCS, Via Manzoni 56, 20089 Rozzano, Italy
3. Department of Gastroenterology and Hepatology, Augusta University Medical Center, Augusta, GA 30912, USA
4. Gastroenterology Unit, Department of Surgical and Medical Sciences, University of Foggia, 71122 Foggia, Italy
5. Department of Gastroenterology, Portsmouth Hospitals University NHS Trust, Portsmouth PO6 3LY, UK
6. Department of Gastroenterology and Hepatology, Kansas City VA Medical Center, Kansas City, MO 66045, USA