Dermatomyositis

Diagnosis

Diagnosing dermatomyositis involves a combination of physical examinations, lab tests, and imaging studies. Your healthcare provider will start by reviewing your symptoms, including muscle weakness and characteristic skin rashes. Because dermatomyositis can resemble other muscle diseases, several tests may be needed to confirm the diagnosis.

Common diagnostic steps include:

• Blood tests: These check for elevated muscle enzymes such as creatine kinase (CK) and aldolase, which can indicate muscle inflammation. Blood tests may also detect specific autoantibodies linked to dermatomyositis.

• Electromyography (EMG): This test measures electrical activity in the muscles to identify abnormal patterns caused by inflammation or muscle damage.

• Imaging tests: MRI scans can reveal areas of muscle inflammation that might not be obvious during a physical exam.

• Muscle or skin biopsy: A small tissue sample is removed from the affected muscle or skin to examine under a microscope. This helps confirm inflammation and rule out other possible causes of symptoms.

Treatment

Treatment for dermatomyositis focuses on managing symptoms, reducing inflammation, and preventing complications. Although there is no cure, many people respond well to therapy and regain muscle strength over time.

Key treatment options include:

• Corticosteroids: Medicines such as prednisone help reduce inflammation and control immune system activity. These are often the first line of treatment.

• Immunosuppressive drugs: If corticosteroids alone are not enough, drugs such as azathioprine or methotrexate may be added to suppress the immune response.

• Physical therapy: Regular exercise guided by a physical therapist helps improve muscle strength, flexibility, and function.

• Sun protection: Since skin symptoms can worsen with sun exposure, using sunscreen and protective clothing is recommended.

• Antimalarial drugs: Medications such as hydroxychloroquine can help manage the skin rash associated with dermatomyositis.

• Intravenous immunoglobulin (IVIG): In more severe cases, IVIG therapy may be used to block harmful antibodies and reduce inflammation.

Early diagnosis and consistent treatment play a vital role in improving muscle strength, reducing skin symptoms, and maintaining overall quality of life in people with dermatomyositis.