1. Department of Gastroenterology, Hepatology and Liver Transplantation Unit, Hospital Universitario Rio Hortega, Valladolid, Spain
2. Division of Medicine, The Institute of Gastroenterology and the Liver Unit, Hadassah Medical Center, Faculty of Medicine, Hebrew University of Jerusalem, Jerusalem, Israel
3. Department of Gastroenterology, Complejo Hospitalario Universitario de Santiago de Compostela, Spain
4. Hepatology and Gastroenterology Department, National Liver Institute, Menoufia University, Egypt