Reconsideration of Dermatomyositis March 20, 1996

Reconsideration of Dermatomyositis March 20, 1996

Dermatomyositis, abbreviated as DM, also known as dermatomyositis with cutaneous manifestations, is a chronic condition primarily affecting the proximal striated muscles of the limbs, accompanied by diverse skin lesions. It is an autoimmune disease, with two main types of lesions: ① muscle lesions; ② skin lesions. It can occur at any age, with women being affected about twice as often as men. Skin manifestations typically include various erythemas and nodules, while muscle involvement affects the proximal striated muscles of the limbs. Initial symptoms include fatigue, followed by pain—both spontaneous pain, tenderness upon palpation, and pain during movement—and eventually muscle weakness. Muscles throughout the body, including ocular and cervical muscles, can be affected, leading to drooping eyelids, double vision, and tilting of the neck. In advanced stages, the disease can involve the heart, liver, lungs, kidneys, and digestive system, potentially resulting in heart failure, interstitial pneumonia, and retinal exudates. Laboratory tests reveal elevated α2 and γ-globulins in protein electrophoresis, with approximately half of the patients testing positive for antinuclear antibodies (ANA) and rheumatoid factor (RF), along with elevated transaminases. Antinuclear antibodies (ANA) are the most reliable indicator of autoimmune diseases, especially for diagnosing systemic lupus erythematosus (with a diagnostic accuracy of 95%). However, this marker can also rise in other chronic inflammatory conditions and in cases of B-cell deficiencies, thereby diminishing its diagnostic value. Regarding treatment, aside from hormones and immunosuppressants, there is no other option; among immunosuppressants, methotrexate is the most commonly prescribed.