1. Department of Internal Medicine, Geriatrics and Nephrologic Diseases, Section of Infectious Diseases, “Alma Mater Studiorum” University of Bologna, S. Orsola-Malpighi Hospital, Bologna, Italy.
2. Department of Internal Medicine and Gastroenterology, “Alma Mater Studiorum” University of Bologna, S. Orsola-Malpighi Hospital, Bologna, Italy.