1. Department of Internal Medicine II, Infectious Diseases, University Hospital Frankfurt, Goethe University Frankfurt, Frankfurt, Germany
2. Department of Internal Medicine II, University Hospital rechts der Isar, School of Medicine, Technical University of Munich, Munich, Germany
3. Interventional and Experimental Endoscopy (InExEn), Department of Internal Medicine II, Gastroenterology, University Hospital Würzburg, Würzburg, Germany
4. Institute of Medical Teaching and Medical Education Research, University Hospital Würzburg, Würzburg, Germany
5. Department of Internal Medicine, Yale School of Medicine, New Haven, CT 06520, USA
6. Department of Gastroenterology, University Hospital Coventry and Warwickshire, Coventry, CV2 2DX, UK