¹Hospital of Modena, Internal Medicine, Modena, Italy, ²University Hospital of Modena, Rheumatology, Modena, Italy, ³University Hospital of Modena, Gastroenterology, Modena, Italy, ⁴University Hospital of Modena, Gastroenterology and Digestive Endoscopy, Modena, Italy

¹University of Chicago Medicine, Inflammatory Bowel Disease Center, Chicago, USA, ²University of Chicago Medicine, Section of Gastroenterology, Hepatology and Nutrition, Chicago, USA

¹Oslo University Hospital, Ulleval, Department of Gastroenterology, Clinics of Medicine, Oslo, Norway, ²University of Oslo, Oslo, Norway, ³Vestfold Hospital Trust, Tonsberg, Department of Gastroenterology, Tonsberg, Norway, ⁴Akershus University Hospital, Oslo, Norway, ⁵Stavanger University Hospital, Department of Gastroenterology, Stavanger, Norway, ⁶Innlandet Hospital Trust, Department of Gastroenterology, Gjovik, Norway, ⁷Aalesund Hospital, Aalesund, Norway, ⁸Telemark Hospital HF, Skien, Skien, Norway, ⁹Ostfold Hospital Trust, Department of Medicine, Kalnes, Norway, ¹⁰Ostfold University College, Health and welfare, Halden, Norway

¹St Mark's Hospital, Colorectal Surgery, London, UK, ²St Mark's Hospital, IBD/Physiology, London, UK

¹Clinical Hospital Centre Rijeka, Gastroenterology, Rijeka, Croatia, ²KBC Rijeka, Department of Pediatrics, Rijeka, Croatia, ³Clinical Hospital Centre Rijeka, Radiology, Rijeka, Croatia, ⁴Clinical Hospital Centre Rijeka, Rijeka, Croatia

¹University of Crete, School of Medicine, Heraklion, Crete, Greece, ²University Hospital of Heraklion, Department of Gastroenterology, Heraklion, Crete, Greece

¹Bulent Ecevit University Medical Faculty, Gastroenterology, Zonguldak, Turkey, ²Bulent Ecevit University School of Medicine, Gastroenterology, Zonguldak, Turkey, ³Sanliurfa Ceylanpinar Public Hospital, Internal Medicine, Sanliurfa, Turkey

¹GoodGut SL, Girona, Spain, ²Universitat de Girona, Microbiologia, Girona, Spain, ³Institut de Investigació Biomèdica de Girona, Girona, Spain, ⁴Hospital Universitari Dr. Josep Trueta, Department of Gastroenterology, Girona, Spain, ⁵Hospital Universitari Germans Trias I Pujol, Department of Gastroenterology, Badalona, Spain, ⁶Hospital Universitari de Bellvitge, Department of Gastroenterology, Hospitalet de Llobregat, Spain, ⁷Hospital de Santa Caterina, Department of Gastroenterology, Salt, Spain, ⁸Centro Médico Teknon, Department of Gastroenterology, Barcelona, Spain

¹Edmond and Lily Safra Children's Hospital, Pediatric Gastroenterology Unit, Tel Hashomer, Israel, ²Alder Hey Children's NHS Foundation Trust, Paediatric Gastroenterology Department, Liverpool, UK, ³Schneider Children's Medical Center of Israel, Institute of Gastroenterology, Nutrition and Liver Disease, Petah Tiqwa, Israel, ⁴University of Naples, Department of Translational Medical Science, Section of Pediatrics, Naples, Italy, ⁵University of Campania "Luigi VAnvitelli", Department of Woman, Child and General Surgery, Naples, Italy, ⁶Shaare Zedak Medical Center, Juliet Keidan Institute of Pediatric Gastroenterology and Nutrition, Jerusalem, Israel, ⁷”Iuliu Hatieganu” University of Medicine and Pharmacy, Pediatric Gastroenterology, Cluj-Napoca, Romania, ⁸Children's Hospital Zagreb, Zagreb, Croatia, ⁹Hvidovre University Hospital, The Paediatric Department, Copenhagen, Denmark, ¹⁰VU University Medical Center, Department of Pediatric Gastroenterology, Amsterdam, The Netherlands, ¹¹University of Messina, Pediatric Gastroenterology, Messina, Italy, ¹²University Hospital Southampton, Department of Paediatrics, Southampton, UK, ¹³Umberto Hospital, Sapienza University of Rome, Pediatric Gastroenterology and Liver Unit, Rome, Italy, ¹⁴Bristol Royal Hospital for Children, Department of Paediatric Gastroenterology, Bristol, UK, ¹⁵Dana-Dwek Children's Hospital, Pediatric Gastroenterology Unit, Tel Aviv, Israel

¹Hospital Universitario Central de Asturias, Gastroenterology, Oviedo, Spain, ²Instituto de Investigación Sanitaria del Principado de Asturias (ISPA), Oviedo, Spain, ³Hospital Universitario Central de Asturias, Immunology, Oviedo, Spain

¹LUMC, Gastroenterology-Hepatology, Leiden, The Netherlands, ²University Hospital Leuven, Department of Gastroenterology and Hepatology, Leuven, Belgium, ³LUMC, Department of Pathology, Leiden, The Netherlands

¹Université Rennes 1 and CHU Pontchaillou Rennes, Service des Maladies de l'Appareil Digestif, Rennes, France, ²CHU Pontchaillou, Department of Surgery, Rennes, France, ³CHU Pontchaillou, Department of Hepatology, Rennes, France, ⁴CHU Pontchaillou, Biochemical unit, Rennes, France

¹Mahidol University, Bangkok, Thailand, ²University of Michigan, Internal Medicine - Gastroenterology, Ann Arbor, Michigan, USA, ³University of Michigan, Internal Medicine - Gastroenterology, Ann Arbor, USA, ⁴University of Michigan, Internal Medicine - Infectious Diseases, Ann Arbor, USA, ⁵University of Michigan, Internal Medicine - Gastroenterology, Ann Arbor, MI, USA

Sapienza University of Rome, Pediatric Gastroenterology and Liver unit, Department of Pediatrics, ROME, Italy

Cleveland Clinic Foundation, Colorectal Surgery, Cleveland, USA

¹Garcia de Orta Hospital, Gastrenterology, Lisbon, Portugal, ²Portuguese Institute of Oncology Francisco Gentil in Lisbon, Department of Gastroenterology, Lisbon, Portugal, ³Garcia de Orta, Garcia de Orta, Lisbon, Portugal, ⁴CUF Descobertas, Pathology, Lisbon, Portugal

School of Medicine Federico II of Naples, Department of Clinical Medicine and Surgery, Naples, Italy

¹University of Edinburgh, Edinburgh, UK, ²Edinburgh Royal Infirmary, Department of Gastroenterology, Edinburgh, UK, ³NHS Lothian - Western General Hospital, Gastrointestinal Unit, Edinburgh, UK

¹ESiOR Oy, Kuopio, Finland, ²Tampere University Hospital, Tampere, Finland, ³Jorvi Hospital, Espoo, Finland, ⁴Turku University Hospital, Turku, Finland, ⁵Janssen-Cilag AS, Oslo, Norway, ⁶Janssen-Cilag Oy, Espoo, Finland, ⁷Peijas Hospital, Vantaa, Finland

University Hospital Santiago de Compostela, Gastroenterology, Santiago, Spain