1 Gastroenterology and Endoscopy Unit, IRCCS Ca' Granda Ospedale Maggiore Policlinico Foundation, Via della Commenda 12, 20122 Milan, Italy. Electronic address: andrea.costantino@policlinico.mi.it.
2 Department of Pathophysiology and Transplantation, University of Milan, Milan, Italy.
3 Azienda Socio-Sanitaria Territoriale di Cremona, Cremona, Italy.
4 Gastroenterology and Endoscopy Unit, IRCCS Ca' Granda Ospedale Maggiore Policlinico Foundation, Via della Commenda 12, 20122 Milan, Italy; Department of Pathophysiology and Transplantation, University of Milan, Milan, Italy.