[1] Med Univ Warsaw, Dept Paediat, Zwirki & Wigury 63A, PL-02091 Warsaw, Poland
[2] Univ Federico II, Dept Translat Med Sci, Paediat Sect, Naples, Italy
[3] Univ Zagreb, Childrens Hosp Zagreb, Sch Med, Univ JJ Strossmayer Sch Med, Osijek, Croatia
[4] Univ Bari, Dept Paediat Gastroenterol, Osped Pediat Giovanni XXIII, Bari, Italy
[5] Univ Childrens Hosp Ljubljana, Dept Gastroenterol Hepatol & Nutr, Univ Med Ctr Ljubljana, Ljubljana, Slovenia
[6] Univ Insubria, Dept Pediat, F Del Ponte Hosp, Varese, Italy
[7] Tel Aviv Univ, Inst Gastroenterol Nutr & Liver Dis, Schneider Childrens Med Ctr, Sackler Fac Med, Tel Aviv, Israel
[8] Univ Amsterdam, Amsterdam UMC, Amsterdam, Netherlands
[9] Vrije Univ Amsterdam, Emma Childrens Hosp, Paediat, Amsterdam, Netherlands
[10] Vrije Univ Brussel, KidZ Hlth Castle, UZ Brussel, Brussels, Belgium
[11] Ben Gurion Univ Negev, Fac Hlth Sci, Beer Sheva, Israel