1. 2nd Department of Internal Medicine, Faculty of Medicine and Louis Pasteur University Hospital, Pavol Jozef Safarik University, Kosice, Slovakia
2. Department of Hepatogastroenterology, Institute for Clinical and Experimental Medicine (IKEM), Prague 4, Czech Republic
3. 2nd Department of Internal Medicine, Faculty of Medicine and Louis Pasteur University Hospital, Pavol Jozef Safarik University, Trieda SNP 1, Kosice 040 11, Slovakia