J H Chong1,2, S Prey2, H T Mya3, A Delarue4, C Labreze2. 1. Department of Pediatric Medicine, Dermatology Service, KK Women's & Children's Hospital, 100 Bukit Timah Road, Singapore, 229899. 2. Department of Pediatric Dermatology, National Centre for Rare Skin Disorders, Hôpital Pellegrin-Enfants, CHU de Bordeaux, Bordeaux, France. 3. Department of Hematology, Singapore General Hospital, Singapore. 4. Pierre Fabre Dermatologie, Lavaur, France.