1. Center for HIV and Hepato-Gastroenterology, Düsseldorf, Germany
2. Department of Medicine III, University-Hospital Aachen, Aachen, Germany
3. CIM Infectious diseases, Münster, Germany
4. Center for Infectiology Berlin, Berlin, Germany
5. Practice for Gastroenterology, Herne, Germany
6. Practice for Gastroenterology, Leverkusen, Germany
7. Infektiologikum, Frankfurt, Germany
8. Infektionsmedizinisches Centrum Hamburg, Hamburg, Germany
9. Department of Medicine I, University-Hospital Bonn, Bonn, Germany