Ulcerative colitis (UC) and Crohn's disease (CD), commonly called inflammatory bowel diseases (IBD), are chronic, relapsing diseases of unknown origin. Although the incidence rates of these diseases have increased significantly during the last thirty years, there are still considerable data discrepancies between different areas of Europe. The majority of previous studies has shown an East-West gradient [1,2]; however, previously published data for parts of Croatia and Hungary have shown an increase of IBD incidence rates similar to some Mediterranean and Western European countries [2,3,4,5].
