1. Department of Gastroenterology and Hepatology University Hospital Essen, University of Duisburg‐Essen Essen Germany
2. Department of Gastroenterology, Hepatology and Infectious Diseases University of Magdeburg Magdeburg Germany
3. Department of General, Visceral and Transplantation Surgery University Hospital Essen, University of Duisburg‐Essen Essen Germany