Gastroenterology, Department of Clinical Medicine and Surgery, School of Medicine "Federico II" of Naples, Via S. Pansini 5, 80131, Naples, Italy. nicola.imperatore@alice.it. Gastroenterology, Department of Clinical Medicine and Surgery, School of Medicine "Federico II" of Naples, Via S. Pansini 5, 80131, Naples, Italy. Hepatology Unit, AORN Cardarelli, Naples, Italy.