1. Department of Gastroenterology, Hepatology and Oncology, Klinikum Ludwigsburg, Germany
2. Department of Internal Medicine 2, Caritas-Krankenhaus Bad Mergentheim gGmbH, Bad Mergentheim, Germany
3. Gastroenterology and Internal Medicine, Rems-Murr-Klinikum Winnenden, Germany
4. Internal Medicine I, University hospital Tuebingen, Tübingen, Germany