[1] Univ Calgary, Dept Pediat, Calgary, AB, Canada
[2] Alberta Childrens Prov Gen Hosp, Calgary, AB, Canada
[3] Univ British Columbia, Dept Pediat, Vancouver, BC, Canada
[4] Univ British Columbia, Dept Dermatol & Skin Sci, Vancouver, BC, Canada
[5] BC Childrens Hosp, Vancouver, BC, Canada
[6] Kuala Lumpur Gen Hosp, Pediat Inst, Kuala Lumpur, Malaysia
[7] Toronto Dermatol Ctr, Toronto, ON, Canada
[8] Hong Kong Childrens Hosp, Dept Paediat & Adolescent Med, Hong Kong, Peoples R China