1. Gastroenterology Division, Valduce Hospital, Como, Italy
2. Gastroenterology Division, Legnano Hospital, ASST Ovest Milanese, Legnano, Italy
3. Blood Transfusion Center, ASST Ovest Milanese, Legnano Hospital, Legnano, Italy
4. Gastroenterology Division, Rho Hospital, ASST Rhodense, Rho, Italy
5. Gastroenterology Division, San Gerardo Hospital, ASST Monza, Monza, Italy