1. Department of Medical Sciences and Public Health, University of Cagliari, Cagliari, Italy
2. Liver Unit, Department of Internal Medicine, University Hospital of Cagliari, Cagliari, Italy
3. Infectious Disease Unit, SS Trinità Hospital, Cagliari, Italy
4. Immunology Unit, Department of Internal Medicine, University Hospital of Cagliari, Cagliari, Italy
5. Department of Clinical and Experimental Medicine, University of Sassari, Sassari, Italy