[1] Med Univ Vienna, Dept Internal Med 3, A-1090 Vienna, Austria
[2] Inst Psychiat & Neurol, Dept Neurol 2, Warsaw, Poland
[3] Heidelberg Univ, Dept Gastroenterol & Hepatol, D-6900 Heidelberg, Germany
[4] Semmelweis Univ, Dept Internal Med 1, H-1085 Budapest, Hungary
[5] Ankara Univ, Sch Med, Dept Gastroenterol, TR-06100 Ankara, Turkey
[6] Univ Innsbruck, Dept Internal Med, A-6020 Innsbruck, Austria
[7] Charles Univ Prague, Fac Med 1, Dept Med 4, CR-11636 Prague 1, Czech Republic
[8] Univ Klinikum Munster, Munster, Germany