Update on dermatomyositis in adults.

Dermatomyositis (DM) in adults has a prevalence of 6-7 per 100,000 population per year. This dedicated compact overview was prepared due to an increasing incidence as well as an often underestimated systemic involvement and new developments in myositis-specific antibodies (MSA). The spectrum of clinical dermatological and systemic symptoms is described. Related diagnostic procedures are depicted, and therapeutic regimens based on the German S2k guidelines and the current literature are presented. The urgency of an early diagnosis is emphasized as about 30 % of patients with DM manifest a tumor. Etiopathology is often associated with pulmonary fibrosis, and inflammation of myositis can cause irreversible muscle damage. Clinical signs and correct interpretation of serological markers can deliver valuable information on the extent of DM, and provide an indication for further diagnostic procedures, prognosis and choice of therapy.