[1] Karolinska Univ Hosp, Astrid Lindgren Childrens Hosp, Stockholm, Sweden
[2] Hosp Reina Sofia, Serv Allerg Adultos, Cordoba, Spain
[3] Sachs Childrens Hosp, Stockholm, Sweden
[4] Hosp Clin Univ Salamanca, Secc Alergia Pediat, Salamanca, Spain
[5] Hosp La Fe Materno Infantil, Secc Alergia Pediat, Valencia, Spain
[6] Uppsala Univ, Childrens Hosp, Uppsala, Sweden
[7] Sahlgrens Univ Hosp, Dept Resp Med & Allergol, Gothenburg, Sweden
[8] Phadia AB, Rapsgatan 7,POB 6460, S-75137 Uppsala, Sweden
[9] Karolinska Inst, Inst Environm Med, Stockholm, Sweden
[10] Gothenburg Univ, Sahlgrenska Acad, Dept Pediat, Gothenburg, Sweden