1. Department of Internal Medicine, Gastroenterology and Hepatology, Catholic University of the Sacred Heart, Foundation A. Gemelli Hospital, Largo Gemelli 8, 00168 Rome, Italy
2. Department of Medical Sciences, IRCCS Casa Sollievo della Sofferenza Hospital, viale Cappuccini, 71013 San Giovanni Rotondo, Italy
3. Department of Internal Medicine, University of Ghana, P .O. BOX LG 23, UGMC, Accra, Ghana
4. Institute of Nuclear Medicine, Catholic University of the Sacred Heart, Foundation A. Gemelli Hospital, Largo Gemelli 8, 00168 Rome, Italy
5. Department of Surgery, Transplantation Service, Catholic University of the Sacred Heart, Foundation A. Gemelli Hospital, Largo Gemelli 8, 00168 Rome, Italy