Expertise for the Management of Myositis

Types of Myositis

There are several types of myositis, including:

• Dermatomyositis (DM). More common in women, DM is characterized by scaly rashes that appear on the face, chest, elbows and knees. Skin symptoms can appear before muscle weakness begins, making it easier to diagnose than other types.
• Clinically Amyopathic Dermatomyositis (CADM). This type of dermatomyositis doesn’t cause muscle weakness and can be diagnosed with a specific antibody. It occurs more commonly in women and causes unique skin symptoms and lung inflammation/scarring.
• Anti Synthetase Syndrome (ASyS). ASyS symptoms vary. Muscle, lung, skin and joint involvement are common. Some types of ASyS can cause significant lung scarring.
• Immune Mediated Necrotizing Myopathy (IMNM). This type of myositis causes the death of muscle cells, leading to muscle weakness and fatigue. It can be associated with the use of anti-cholesterol medications like statins or underlying cancers.
• Overlap Myositis. Occurs with other underlying autoimmune connective tissue disease and causes muscle inflammation, including scleroderma, systemic lupus erythematosus (SLE), rheumatoid arthritis, Sjogren’s Syndrome and vasculitis.
• Sporadic Inclusion Body Myositis (sIBM). This is the most common type of myopathy in people over age 50. It progresses more slowly and primarily affects the smaller muscles in the forearms, hands and thighs.
• Polymyositis (PM). A rare form of myositis, PM doesn’t cause any skin symptoms. Age of onset and symptoms are variable.
• Juvenile Myositis (JM). Any type of myositis that occurs in children under 18. In addition to muscle weakness and skin symptoms, JM may also cause a hoarse voice, stomach aches and irritability.

What Causes Myositis?

The cause of myositis is unknown. In people with a genetic predisposition, common triggers include environmental factors and medications like statins or some immunotherapies.

Symptoms of Myositis

The signs and symptoms of myositis vary greatly from person to person. Many people seek medical attention when they start having falls or difficulty climbing stairs or rising from a seated position due to muscle weakness. Other common symptoms may include:

• Unusual rashes
• Breathing problems.
• Difficulty swallowing (dysphagia)
• Joint pain
• Extreme fatigue
• Muscle pain and tenderness (rare)

How is Myositis Diagnosed?

In addition to taking a complete medical, family and lifestyle history, your doctor will perform a comprehensive physical examination to assess muscle strength and look for obvious signs of inflammation. The following tests may be ordered to confirm or rule out the diagnosis:

• Blood tests. Detect elevated levels of muscle enzymes that may indicate muscle damage and/or inflammation. Blood tests can also detect antibodies to identify the type of myositis.
• Magnetic resonance imaging (MRI). To help identify muscle inflammation and look for signs of fluid retention (edema) in the muscles and tissues.
• Electromyography (EMG). Measures the electrical activity in the muscles. EMG can help to identify muscle weakness or damage.
• Nerve conduction studies (NCS). Measures how well the nerves send electrical signals. NCS can help distinguish between nerve disorders and the muscle changes associated with myositis.
• Muscle or skin biopsy. A small sample of muscle tissue or skin is examined under a microscope for signs of inflammation and other abnormalities associated with myositis.
• High resolution computerized tomography (HRCT) chest. Patients with certain types of myositis are at higher risk of lung scarring. HRCT is performed to rule out lung involvement in those cases.
• Pulmonary function tests (PFTs). To monitor disease progression and guide disease management decisions.
• Swallowing studies. May be ordered if the muscles involved in swallowing are affected.

Medical Management of Myositis

There is no cure for myositis, but a variety of therapies can help manage the disease. The primary goal of treatment is to reduce inflammation, prevent disease progression and improve quality of life. Your team may include rheumatologists, pulmonologists, neurologists, dermatologists and physical, speech and occupational therapists.

Treatment for myositis may include:

• Corticosteroids and immunosuppressant medications such as methotrexate, azathioprine, mycophenolate mofetil, tacrolimus, rituximab or cyclophosphamide.
• Intravenous immunoglobulins (IVIGs).
• Periodic blood tests to monitor treatment progress.
• Physical or occupational therapy to strengthen muscles and improve mobility.
• Although rare, in some cases surgical procedures may be recommended to manage myositis-related complications for swallowing difficulties.

Lifestyle Strategies to Manage Myositis

While receiving medical therapy, several lifestyle modifications will also be recommended to help you restore and maintain muscle strength, range of motion and overall health. These may include:

• Stretching. A program of regular stretching exercises may be prescribed. Heat and gentle massage may also be recommended.
• Adequate rest. Practice good sleep habits and limit strenuous activity. Take frequent breaks during the day.
• Stress reduction. Some people find relief from myositis symptoms with alternative therapies like acupuncture, yoga or meditation. Talk to your doctor about the potential benefit of these therapies for you.
• An anti-inflammatory diet. An anti-inflammatory diet emphasizes whole, unprocessed foods like fruits, vegetables, whole grains, lean proteins and healthy fats, while limiting processed foods, sugary drinks and unhealthy fats.
• Staying hydrated. Drinking plenty of water can reduce inflammation by flushing out toxins and keeping joints lubricated, which helps manage muscle pain and discomfort. In addition, tea made with lemon, ginger and turmeric can provide numerous health benefits including reduced inflammation.