T M Yan1, H Zhang2, X Y Wu1, Z Y Zhang3. 1. Department of Dermatology, The University of Hong Kong Shenzhen Hospital, Shenzhen, China. 2. Department of Dermatology, Baoan Central Hospital, Shenzhen, China. 3. Department of Dermatology, The Eighth Affiliated hospital of Sun Yat-sen University, Shenzhen, China.