1. European Hidradenitis Suppurativa Foundation e.V.; Dessau Germany
2. Department of Dermatology; Hôpital Erasme; Université Libre de Bruxelles; Brussels Belgium
3. Department of Dermatology; University Hospital of Zurich; Zurich Switzerland
4. Department of Dermatology; University Hospital of North Norway; Troms Norway
5. Department of Dermatology; Deventer Hospital; Deventer The Netherlands
6. Department of Dermatology; Hospital of Manises; Valencia Spain
7. Department of Dermatology & Wound Healing; Cardiff University; Cardiff UK
8. St John's Institute of Dermatology; London UK
9. Pasteur Institute; Paris France
10. Private practice; Paris France
11. Department of Dermatology; Hospital Henri-Mondor; Créteil France
12. Department of Dermatology; Azienda Ospedaliero-Universitaria di Ferrara; Ferrara Italy
13. Department of Dermatology; Erasmus University Medical Center; Rotterdam The Netherlands
14. Department of Dermatology; Health Sciences Faculty; Roskilde Hospital; University of Copenhagen; Copenhagen Denmark
15. Departments of Dermatology, Venereology, Allergology and Immunology; Dessau Medical Center; Dessau Germany