Wiebke Sondermann1, Eva Hadaschik1, Christof Specker2. 1. Department of Dermatology, Venereology and Allergology, University Hospital Essen, University Duisburg-Essen, Essen, Germany. 2. Clinic for Rheumatology and Clinical Immunology, Evangelisches Krankenhaus Kliniken Essen-Mitte, Essen, Germany.