1. Institute of Pathology, University of Cologne Cologne Germany
2. Institute of Pathology, University Duisburg‐Essen Essen Germany
3. Department of Paediatric Gastroenterology, Hepatology, and Transplant Medicine Children's Hospital, University Duisburg‐Essen Essen Germany
4. Department of Gastroenterology, Hepatology and Transplant Medicine University Duisburg‐Essen Essen Germany
5. MVZ of Pathology and Cytology Rhein‐Sieg Troisdorf Germany
6. Institute of Pathology, University of Bonn Bonn Germany