1 Italian Society of Pediatrics, Rome, Italy; Institute of Pediatrics, Catholic University Medical School, Rome, Italy; Campus Bio-Medico University Medical School, Rome, Italy. Electronic address: pietro.ferrara@unicatt.it.
2 Italian Society of Pediatrics, Rome, Italy; European Paediatric Association-Union of National European Paediatric Societies and Associations, Berlin, Germany; Institute of Pediatrics, University of Palermo, Palermo, Italy.
3 Campus Bio-Medico University Medical School, Rome, Italy.
4 European Paediatric Association-Union of National European Paediatric Societies and Associations, Berlin, Germany; Children's Hospital, Hannover Medical School, Hannover, Germany.
5 Italian Society of Pediatrics, Rome, Italy; European Paediatric Association-Union of National European Paediatric Societies and Associations, Berlin, Germany; Institute of Pediatrics, University of Foggia, Istituto di Ricovero e Cura a Carattere Scientifico "Casa Sollievo", Foggia, Italy.