1. Gastroenterology and Endoscopy Unit; Fondazione IRCCS Cà Granda Ospedale Maggiore Policlinico; Milano Italy
2. NIHR Nottingham Biomedical Research Centre (BRC); Nottingham University Hospitals NHS Trust and the University of Nottingham; Nottingham UK
3. Nottingham Digestive Diseases Centre, School of Medicine; University of Nottingham; Nottingham UK