[1] Univ Helsinki, Cent Hosp, Dept Dermatol, FIN-00170 Helsinki, Finland
[2] Great Ormond St Hosp Sick Children, Dept Dermatol, London WC1N 3JH, England
[3] Univ Amsterdam, Acad Med Ctr, Dept Dermatol, NL-1012 WX Amsterdam, Netherlands
[4] Serv Dermatol, St Etienne, France
[5] Univ Hosp, Dept Dermatol, Utrecht, Netherlands
[6] Radboud Univ Nijmegen Med Ctr, Dept Dermatol, Nijmegen, Netherlands
[7] Univ Hosp Lewisham, Skin Therapy Res Unit, London, England
[8] Birmingham Childrens Hosp, Dept Paediat Dermatol, Birmingham, W Midlands, England
[9] Univ Szeged, Dept Dermatol, Szeged, Hungary
[10] Univ Oulu, Cent Hosp, Dept Dermatol, SF-90220 Oulu, Finland