Myositis is a group of rare autoimmune diseases that cause inflammation of the muscles, leading to muscle weakness. It can also affect the skin, lungs, joints, and other organs.

 

The main types include:

• Polymyositis – Affects muscles on both sides of the body

• Dermatomyositis – Includes skin rash along with muscle weakness

• Inclusion Body Myositis (IBM) – More common in older adults; progresses slowly

• Juvenile Myositis – Occurs in children

 

Common Signs & Symptoms

• Gradual, symmetric muscle weakness, especially in hips, thighs, shoulders, and neck

• Difficulty climbing stairs, rising from a chair, or lifting objects

• Fatigue

• Muscle pain or tenderness

• Skin rash (in dermatomyositis)

• Difficulty swallowing or breathing (in more severe cases)

• Joint pain or inflammation

 

Causes & Risk Factors

• Autoimmune reaction (body’s immune system attacks its own muscle tissue)

• Possible triggers: infections, medications, or other autoimmune diseases

• Can occur at any age; more common in women

 

Diagnosis

Diagnosis involves a combination of:

• Physical exam and symptom history

• Blood tests (e.g., elevated muscle enzymes like CK)

• Electromyography (EMG) to test muscle function

• Muscle biopsy to examine tissue under a microscope

• MRI to detect inflammation

• Autoantibody testing (e.g., anti-Jo-1 antibodies)

 

Treatment & Management

There is no cure, but symptoms can be managed effectively.

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Treatment options include:

• Corticosteroids (e.g., prednisone) to reduce inflammation

• Immunosuppressive drugs (e.g., methotrexate, azathioprine)

• IVIG or biologics in certain cases

• Physical therapy to maintain strength and mobility

• Sun protection for those with skin involvement

 

Living with Myositis

• Stay active with guided physical therapy

• Eat a balanced diet and manage fatigue

• Monitor for complications (lung or swallowing issues)

• Keep regular appointments with your rheumatologist