[1] Heim Pal Childrens Hosp, Dept Gastroenterol & Nephrol, H-1089 Budapest, Hungary
[2] Heim Pal Childrens Hosp, Dept Pediat, H-1089 Budapest, Hungary
[3] Heim Pal Childrens Hosp, Dept Pathol, H-1089 Budapest, Hungary
[4] Heim Pal Childrens Hosp, Cent Lab, H-1089 Budapest, Hungary
[5] State Inst Publ Hlth, Budapest, Hungary
[6] Hlth Officer Serv, Budapest, Hungary