Dermatomyositis is a muscle disease that involves inflammation and a skin rash. It is a type of inflammatory myopathy.
Causes, incidence, and risk factors
The cause of dermatomyositis is unknown. Experts think it may be due to a viral infection of the muscles or a problem with the body's immune system. It may also occur in patients who have cancer in the abdomen, lung, or other parts of the body.
Anyone can develop dermatomyositis. It most commonly occurs in children age 5 - 15 and adults age 40 - 60. Women develop this condition more often than men.
Polymyositis is a similar condition, but the symptoms do not include a skin rash.
Kevin Berman, MD, PhD, Atlanta Center for Dermatologic Disease, Atlanta, GA. Review provided by VeriMed Healthcare Network. Also reviewed by A.D.A.M. Health Solutions, Ebix, Inc., Editorial Team: David Zieve, MD, MHA, Bethanne Black, Stephanie Slon, and Nissi Wang.