[1] IRCCS Burlo Garofolo, Inst Maternal & Child Hlth, I-34137 Trieste, Italy
[2] Univ Messina, Dept Paediat Sci, Messina, Italy
[3] Inst Giannina Gaslini, Paediat Gastroenterol Unit, Genoa, Italy
[4] Univ Florence, Meyer Childrens Hosp, Dept Sci Woman & Child Hlth, Florence, Italy
[5] Childrens Hosp V Buzzi, Dept Paediat, Milan, Italy
[6] Univ Pisa, Dept Paediat Gastroenterol, Pisa, Italy
[7] Univ Trieste, Trieste, Italy
[8] Spedali Civil Brescia, Dept Pathol, I-25125 Brescia, Italy