dermatomysitis

Dermatomyositis is a rare idiopathic inflammatory myopathy characterized by muscle weakness and a distinctive skin rash. It can affect people of all ages, but is more common in women and adults between the ages of 40 and 60. The cause of dermatomyositis is not fully understood, but it is believed to be an autoimmune disease where the body’s immune system mistakenly attacks healthy tissues. There may be genetic predispositions and environmental triggers, such as viral infections or certain medications, that contribute to its development.

The hallmark symptoms include progressive muscle weakness, particularly in the proximal muscles like those of the shoulders, hips, and thighs, which can make everyday activities such as climbing stairs or lifting objects difficult. The characteristic skin rash can appear before, during, or after the onset of muscle weakness. Common skin manifestations include a heliotrope rash, which is a purplish discoloration around the eyes, and Gottron’s papules, which are raised, reddish-purple bumps over the knuckles. Other skin findings can include a shawl sign across the upper back and shoulders, and scaling on the scalp.

Diagnosis typically involves a combination of clinical examination, blood tests to detect muscle enzymes and antibodies, electromyography to assess muscle electrical activity, and muscle or skin biopsy. Treatment aims to reduce inflammation, improve muscle strength, and manage skin symptoms. It often involves corticosteroids, immunosuppressive drugs, and physical therapy. While there is no cure for dermatomyositis, treatment can often control the disease and prevent further damage.