1. University of Belgrade, Faculty of Medicine, Belgrade, Serbia + Clinical Center of Serbia, Clinic for Gastroenterology and Hepatology, Belgrade, Serbia
2. Mayo Clinic College of Medicine and Science, Rochester, MN, USA
3. Clinical Center of Serbia, Clinic for Gastroenterology and Hepatology, Belgrade, Serbia
4. Clinical Center of Serbia, Clinic for Nephrology, Belgrade, Serbia
5. University of Belgrade, Faculty of Medicine, Belgrade, Serbia + Clinical Centre of Serbia, Emergency Center, Department of Emergency Surgery, Belgrade, Serbia