1 Urticaria Center of Reference and Excellence (UCARE), Institute of Allergology, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany.
2 Fraunhofer Institute for Translational Medicine and Pharmacology ITMP, Allergology and Immunology, Berlin, Germany.
3 Division of Pediatric Pulmonology, Allergy and Endocrinology, Department of Pediatrics and Adolescent Medicine, Comprehensive Center of Pediatrics, Medical University of Vienna, Vienna, Austria.
4 Department of Allergology, Clinica San Carlo, Paderno Dugnano, Milan, Italy.
5 Department of Allergy and Clinical Immunology, Clinica Universidad de Navarra, Instituto de Investigación Sanitaria de Navarra (IdiSNA), RETIC de Asma, Reacciones Adversas y Alérgicas (ARADYAL), Pamplona, Spain.
6 Department of Dermatology, Hospital Del Mar, IMIM, Universitat Autònoma y Universitat Pompeu Fabra, Barcelona, Spain.
7 St John's Institute of Dermatology, Guy's Hospital, London, UK.
8 Department of Dermatology and Allergology, University Medical Center Giessen and Marburg, Justus-Liebig University Gießen, Gießen, Germany.
9 Department of Allergy and Clinical Immunology, 424 General Military Training Hospital, Thessaloniki, Greece.
10 Department of Human Medicine and Health Sciences, University Clinic of Dermatology and Allergy, University of Oldenburg, Oldenburg, Germany.
11 Department of Dermatology, University Medical Center Mainz, Mainz, Germany.
12 Allerdia Inc, Los Angeles, California, USA.
13 Department of Dermatology and Allergy Centre, Odense University Hospital, University of Southern Denmark, Odense, Denmark.
14 Servicio de Alergia, Instituto de Investigación Sanitaria (IIS)-Hospital Universitario de La Princesa, Madrid, Spain.
15 Department of Dermatology, Medical University of Vienna, Vienna, Austria.
16 Allergy Unit, 2nd Department of Dermatology and Venereology, Medical School, National and Kapodistrian University of Athens, "Attikon" University Hospital, Athens, Greece.
17 Department of Dermatology, Norfolk and Norwich University Hospital, Norwich, UK.
18 Allergy Unit, Department of Dermatology, University Hospital, Zürich, Switzerland.
19 Christine Kühne Center for Allergy Research and Education CK-CARE, Davos, Switzerland.
20 Division of Allergy and Clinical Immunology, University of Toronto, Toronto, Ontario, Canada.
21 Faculty of Medicine, Bnai-Zion Medical Center, Haifa, Israel.
22 Department of Dermatology and Venerology, Kepler University Hospital, Linz, Austria.