1. Faculty of Dental Medicine and Health Osijek, Josip Juraj Strossmayer University of Osijek, 31000 Osijek, Croatia
2. Faculty of Medicine Osijek, Josip Juraj Strossmayer University of Osijek, 31000 Osijek, Croatia
3. Health Center Osijek-Baranja County, 31000 Osijek, Croatia
4. Department of Medicine, Division of Gastrenterology/Hepatology, University of Connecticut Health Center, Farmington, CT 06030, USA