1 Department of Pediatric Surgery, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy.
2 Service of Paediatric Hepatology, Department of Paediatrics, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy.
3 Department of Pediatric Surgery, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy; University of Milan, Italy.
4 Department of Pediatric Surgery, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy. Electronic address: francesco.macchini@policlinico.mi.it.