1. Department of Medicine (Gastroenterology, Infectious Diseases, Rheumatology), Charité-Universitätsmedizin Berlin , Berlin , Germany
2. Department of Histopathology, Royal London Hospital , London , UK
3. Academic Department of Gastroenterology, Ethnikon and Kapodistriakon University of Athens , Laikon Hospital , Athens , Greece
4. ESADI Clinic and Gastroenterology Unit, Santa Isabel Hospital, Blumenau , Santa Catarina , Brazil
5. Colorectal Unit, Gastrosaude Clinic, Marilia , Sao Paulo , Brazil
6. f Department of Surgery, UNESP Botucatu , Sao Paulo , Brazil
7. Division of Gastroenterology and Hepatology, University Hospital Zurich, University of Zurich , Zurich , Switzerland