1Department of Gastroenterology, Università Politecnica delle Marche, Ancona, Italy
2Division of Gastroenterology, Department of Medicine, University of California San Diego, School of Medicine, CA, United States
3Division Research, Central Texas Veterans Health Care System, Scott & White Digestive Disease Research Center, Department of Medicine, Division Gastroenterology, Scott & White Hospital and Texas A&M Health Science Center, College of Medicine, Temple, TX, United States
4Division of Gastroenterology, Polo Pontino, Università degli Studi “La Sapienza”, Rome, Italy