1. Centro Hospitalar de Lisboa Ocidental, EPE, Lisboa, Portugal
2. Diagnostic & Research Centre for Molecular BioMedicine, Institute of Pathology, Medical University of Graz, Graz, Austria
3. Department of Internal Medicine, Krankenhaus der Barmherzigen Brüder, St. Veit/Glan, Austria
4. Private Practice of Gastroenterology, Bayreuth, Germany
5. Private Practice of Gastroenterology, Osnabrück, Germany
6. Department of Surgery, Division of General Surgery, Medical University of Graz, Graz, Austria
7. Department of Internal Medicine, Division of Gastroenterology and Hepatology, Medical University of Graz, Graz, Austria
8. Institute of Pathology, Klinikum Bayreuth, Bayreuth, Germany