[1] Karolinska Univ, Huddinge Hosp K63, Dept Med, Div Gastroenterol Hepatol,Karolinska Inst, S-14186 Huddinge, Sweden
[2] Med Univ Graz, Dept Med, Div Gastroenterol & Hepatol, Graz, Austria
[3] Univ Bonn, Univ Hosp Bonn, Dept Internal Med 1, D-5300 Bonn, Germany
[4] Karolinska Univ, Huddinge Hosp, Dept Pediat, Karolinska Inst, S-14186 Huddinge, Sweden
[5] Karolinska Univ, Huddinge Hosp, Dept Surg, Karolinska Inst, S-14186 Huddinge, Sweden
[6] Hannover Med Sch, Dept Gastroenterol Hepatol & Endocrinol, D-3000 Hannover, Germany