[1] Univ Libre Bruxelles, Queen Fabiola Childrens Univ Hosp, B-1020 Brussels, Belgium
[2] Grp Hop Inst Catholique Lille GH ICL, Clin Paediat St Antoine, St Vincent de Paul Hosp, Lille, France
[3] Sci Inst Publ Hlth, Med Microbiol Lab, Brussels, Belgium
[4] Med Univ Wroclaw, Dept Paediat, Wroclaw, Poland
[5] Karolinska Univ Hosp, Dept Paediat, Stockholm, Sweden
[6] Univ Med Ctr, Dr V Hauner Childrens Hosp, Munich, Germany
[7] Univ Piemonte Orientale, Dept Paediat, Novara, Italy
[8] Hosp Univ Nino Jesus, Dept Paediat, Madrid, Spain
[9] Hosp 12 Octubre, Dept Paediat, E-28041 Madrid, Spain
[10] Univ Amsterdam, Acad Med Ctr, NL-1105 AZ Amsterdam, Netherlands
[11] Charles Univ Prague, Fac Med Pilsen, Dept Paediat, Prague, Czech Republic
[12] Semmelweis Univ, Dept Paediat 1, H-1085 Budapest, Hungary
[13] Univ Athens, Dept Paediat 1, Athens, Greece
[14] Marmara Univ Hosp, Dept Paediat, Istanbul, Turkey
[15] Victor Segalen Bordeaux 2 Univ, INSERM, U853, Bordeaux, France