1. Information Network of Departments of Dermatology; University of Göttingen; 37075 Göttingen Germany
2. Department of Dermatology; University of Essen; 45122 Essen Germany
3. Department of Dermatology, Environmental Medicine, and Health Theory; University of Osnabrück; 49069 Osnabrück Germany
4. Department of Dermatology; University of Heidelberg; 69115 Heidelberg Germany
5. Department of Dermatology; University of Lübeck; 23538 Lübeck Germany
6. Division of Clinical and Molecular Allergology; Research Centre Borstel, Airway Research Centre North, Member of the German Centre for Lung Research; 23845 Borstel Germany