1. Department of Medicine, Karolinska Institute, Stockholm Söder Hospital, 118 83 Stockholm, Sweden
2. Department of Gastroenterology and Hepatology, Karolinska University Hospital, 141 86 Stockholm, Sweden
3. Department of Gastroenterology, Ersta Hospital, 116 91 Stockholm, Sweden
4. Department of Medicine, Danderyd Hospital, 182 88 Stockholm, Sweden