1. Gastroenterology and Digestive Endoscopy, IRCCS Ospedale San Raffaele, Via Olgettina 58, 20132 Milan, Italy
2. Unit of Immunology, Rheumatology, Allergy and Rare Diseases, IRCCS Ospedale San Raffaele, 20132 Milan, Italy
3. Pathology Unit, IRCCS Ospedale San Raffaele, 20132 Milan, Italy
4. Gastroenterology and Endoscopy Unit, Fondazione Istituto S. Raffaele—G. Giglio, 90015 Cefalu, Italy
5. Faculty of Medicine, Università Vita-Salute San Raffaele, 20132 Milan, Italy