[1] Mater Dei Hosp, Dept Dermatol, Msida, Malta
[2] European Hidradenitis Suppurat Fdn eV, Dessau, Germany
[3] Univ Malta, Fac Med & Surg, Dept Pathol, Msida, Malta
[4] Univ Libre Bruxelles, Erasme Hosp, Dept Dermatol, Brussels, Belgium
[5] Univ Malta, Fac Med & Surg, Ctr Mol Med & Biobanking, Msida, Malta
[6] Univ New South Wales, Liverpool Hosp, Dept Dermatol, Sydney, NSW, Australia