[1] Tech Univ Munich, Dept Internal Med 2, Klinikum Rechts Isar, Munich, Germany
[2] Tech Univ Munich, Dept Surg, Klinikum Rechts Isar, Munich, Germany
[3] Univ Spital Zurich, Dept Gastroenterol & Hepatol, Zurich, Switzerland
[4] Private Practice Gastroenterol & Endoscopy, Munich, Germany
[5] Tech Univ Munich, Inst & Informat Med, Sch Med, Munich, Germany
[6] Philipps Univ Marburg, Inst Pathol, Marburg, Germany