[1] Charite, Allergie Ctr Charite, Dept Dermatol & Allergy, D-10117 Berlin, Germany
[2] Clin San Carlo, Paderno Dugnano, MI, Italy
[3] Odense Univ Hosp, Odense Area, Dept Dermatol, Allergy Ctr, Odense, Denmark
[4] Univ Genoa, DIMI, Genoa, Italy
[5] Univ Autonoma Barcelona, Hosp Mar, IMAS, Dept Dermatol, E-08193 Barcelona, Spain
[6] Norfolk & Norwich Univ Hosp, Dermatol Ctr, Norwich, Norfolk, England
[7] Hannover Med Sch, Dept Dermatol & Allergol, Hannover, Germany
[8] Univ Hosp RWTH Aachen, Dept Dermatol, Aachen, Germany
[9] Med Univ Silesia, Clin Dept Internal Dis Allergol & Clin Immunol, Katowice, Poland
[10] Johns Hopkins Univ, Dept Med, Baltimore, MD USA
[11] Ctr Med Docente La Trinidad, Allergy & Immunol Dept, Caracas, Venezuela
[12] Univ Zurich Hosp, Dept Dermatol, Allergy Unit, CH-8091 Zurich, Switzerland
[13] McMaster Univ, Dept Clin Epidemiol & Biostat, Hamilton, ON, Canada
[14] Johannes Gutenberg Univ Mainz, Dept Dermatol, Mainz, Germany
[15] Univ Bari, Unit Dermatol, Bari, Italy