1. Pediatric Gastroenterology and Liver Unit, Department of Maternal and Child Health, Umberto I Hospital, Sapienza University of Rome , Rome , Italy
2. Unit of Gastroenterology and Nutrition, Meyer Children’s Hospital , Florence , Italy
3. Gastroenterologia ed Endoscopia Pediatrica, IRCCS Istituto Giannina Gaslini , Genoa , Italy
4. Pediatric Gastroenterology Unit, Maggiore Hospital , Bologna , Italy
5. Department of Translational Medical Science, Section of Pediatrics, University of Naples Federico II , Naples , Italy
6. Pediatrics , Fondazione IRCCS San Gerardo dei Tintori, Monza , Italy
7. Institute for Maternal and Child Health, IRCCS Burlo Garofolo , Trieste , Italy
8. Unit of Gastroenterology, Digestive Endoscopy, Hepatology and Care of Children with Liver Transplantation, University Hospital of Padova , Padova , Italy