1 General Surgery Department, ASST-Vimercate, Vimercate 20871, Italy.
2 Division of Gastroenterology and Hepatology, Stanford University School of Medicine, Stanford, CA 94305, United States.
3 Department of Clinical and Experimental Medicine, University of Foggia, Foggia 71122, Italy.
4 Department of Surgical and Medical Sciences, Gastroenterology Unit, University of Foggia, Viale Pinto, 1, Foggia 71122, Italy.
5 Department of Surgical and Medical Sciences, Gastroenterology Unit, University of Foggia, Viale Pinto, 1, Foggia 71122, Italy. Electronic address: antonio.facciorusso@virgilio.it.