1 Division of Rheumatology and Clinical Immunology, Department of Medicine, Queen Mary Hospital, The University of Hong Kong, Hong Kong, China.
2 Department of Immunology, Auckland City Hospital, Grafton, Auckland, New Zealand; Department of Medicine, University of Auckland, Auckland, New Zealand.
3 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; Immunology and Allergology, Fraunhofer Institute for Translational Medicine and Pharmacology ITMP, Berlin, Germany.
4 Division of Allergy and Clinical Immunology, Department of Medicine, University of Cape Town, Cape Town, South Africa; Allergy and Immunology Unit, University of Cape Town Lung Institute, Cape Town, South Africa.
5 Division of Rheumatology, Allergy, and Immunology, University of California, San Diego, La Jolla, Calif.
6 Division of Rheumatology and Clinical Immunology, Department of Medicine, Queen Mary Hospital, The University of Hong Kong, Hong Kong, China. Electronic address: liphilip@hku.hk.