[1] Jagiellonian Univ, Coll Med, Dept Pediat Gastroenterol & Nutr, Krakow, Poland
[2] Med Univ Warsaw, Dept Pediat Gastroenterol & Nutr, Warsaw, Poland
[3] Childrens Mem Hlth Inst, Dept Gastroenterol Hepatol & Feeding Disorders, Warsaw, Poland
[4] Pomeranian Med Univ, Pediat & Pediat Nursery Unit, Szczecin, Poland
[5] Med Univ Wroclaw, Dept Pediat Gastroenterol & Nutr, Wroclaw, Poland
[6] Area Hosp Torun, Dept Pediat & Gastroenterol, Torun, Poland
[7] Holy Spirit Hosp Sandomierz, Childrens Cardiol Subunit, Dept Pediat, Sandomierz, Poland
[8] Univ Rzeszow, Coll Med, Dept Pediat, Rzeszow, Poland
[9] Nicolaus Copernicus Univ, Coll Med, Dept Pediat Endoscopy & Gastrointestinal Funct Te, Bydgoszcz, Poland