Enver Zerem1, Nada Pavlović-Čalić2, Bahrija Haračić2. 1. Department of Medical Sciences, The Academy of Sciences and Arts of Bosnia and Herzegovina, Department of Gastroenterology, University Clinical Center Tuzla, Tuzla, Bosnia and Herzegovina. 2. Department of Gastroenterology, University Clinical Center Tuzla, Tuzla, Bosnia and Herzegovina.