1. Gastrounit, Medical Division, Copenhagen University Hospital Hvidovre, Hvidovre, Denmark
2. Medical Department, Zealand University Hospital, Køge [Koege], Denmark
3. Susan and Leonard Feinstein IBD Clinical Center, Icahn School of Medicine at Mount Sinai, New York, NY, USA
4. Dartmouth-Hitchcock Medical Center, Section of Gastroenterology and Hepatology, Lebanon, NH, USA