1. Department of Dermatology; University Hospital Schleswig-Holstein; Campus Lübeck, Ratzeburger Allee 160 D-23538 Lübeck Germany
2. Department of Dermatology; University Hospital Zürich; University of Zürich; Zürich Switzerland
3. Department of Plastic and Reconstructive Surgery; University Children's Hospital Zürich; Zürich Switzerland
4. Department of Pediatric Dermatology; University Children's Hospital Zürich; Zürich Switzerland