Overview

Polymyositis (pol-e-my-o-SY-tis) is an uncommon inflammatory disease that causes muscle weakness affecting both sides of your body. Having this condition can make it difficult to climb stairs, rise from a seated position, lift objects or reach overhead.

Polymyositis most commonly affects adults in their 30s, 40s or 50s. It's more common in blacks than in whites, and women are affected more often than men. Signs and symptoms usually develop gradually, over weeks or months.

While there is no cure for polymyositis, treatment — ranging from medications to physical therapy — can improve your muscle strength and function.

Source: http://www.mayoclinic.com

Symptoms

The muscle weakness associated with polymyositis involves the muscles closest to the trunk, such as those in your hips, thighs, shoulders, upper arms and neck. The weakness affects both the left and right sides of your body, and tends to gradually worsen.

When to see a doctor

Seek medical attention if you develop unexplained muscle weakness.

Source: http://www.mayoclinic.com

Causes

The exact cause of polymyositis is unknown, but the disease shares many characteristics with autoimmune disorders, in which your immune system mistakenly attacks your own body tissues.

Source: http://www.mayoclinic.com

Diagnosis

If your doctor suspects you have polymyositis, he or she might suggest some of the following tests:

• Blood tests. A blood test will let your doctor know if you have elevated levels of muscle enzymes, which can indicate muscle damage. A blood test can also detect specific autoantibodies associated with different symptoms of polymyositis, which can help in determining the best medication and treatment.
• Electromyography. This test involves inserting a thin needle electrode through the skin into the muscle. Electrical activity is measured as you relax or tighten the muscle, and changes in the pattern of electrical activity can confirm a muscle disease. The doctor can determine the distribution of the disease by testing different muscles.
• Magnetic resonance imaging (MRI). A scanner creates cross-sectional images of your muscles from data generated by a powerful magnetic field and radio waves. Unlike a muscle biopsy, an MRI can assess inflammation over a large area of muscle.
• Muscle biopsy. During this test, a small piece of muscle tissue is surgically removed for laboratory analysis. Analysis may reveal abnormalities, such as inflammation, damage, certain proteins or enzyme deficiencies.

Source: http://www.mayoclinic.com

Complications

Possible complications of polymyositis include:

• Difficulty swallowing. If the muscles in your esophagus are affected, you may have problems swallowing (dysphagia), which in turn may cause weight loss and malnutrition.
• Aspiration pneumonia. Difficulty swallowing may also cause you to breathe food or liquids, including saliva, into your lungs (aspiration), which can lead to pneumonia.
• Breathing problems. If your chest muscles are affected by the disease, you may experience breathing problems, such as shortness of breath or, in severe cases, respiratory failure.

Associated conditions

Although these are not complications, polymyositis is often associated with other conditions that may cause further complications of their own, or in combination with polymyositis symptoms. Associated conditions include:

• Raynaud's phenomenon. This is a condition in which your fingers, toes, cheeks, nose and ears initially turn pale when exposed to cold temperatures.
• Other connective tissue diseases. Other conditions, such as lupus, rheumatoid arthritis, scleroderma and Sjogren's syndrome, can occur in combination with polymyositis.
• Cardiovascular disease. Polymyositis may cause the muscular walls of your heart to become inflamed (myocarditis). In a small number of people who have polymyositis, congestive heart failure and heart arrhythmias may develop.
• Lung disease. A condition called interstitial lung disease may occur with polymyositis. Interstitial lung disease refers to a group of disorders that cause scarring (fibrosis) of lung tissue, making lungs stiff and inelastic. Signs and symptoms include a dry cough and shortness of breath.
• Cancer. People who have polymyositis have an elevated risk of cancer.

Coping and support

Living with a chronic autoimmune disease can make you wonder at times whether you're up to the challenge. To help you cope, try supplementing your medical care with the following suggestions:

• Know your illness. Read all you can about polymyositis and other muscle and autoimmune disorders. Talk to other people who have a similar condition. Don't be afraid to ask your doctor any questions that you may have concerning your illness, diagnosis or treatment plan.
• Be a part of your medical team. Consider yourself, your doctor and any other medical experts involved as a united front in the fight against your disease. Following the treatment plan you agreed to is vital. Keep your doctor updated on any new signs or symptoms you may experience.
• Know and assert your limits. Learn to say no effectively and ask for help when you need it.
• Rest when you're tired. Don't wait until you're exhausted. This will only set you back further as your body tries to recuperate. Learning to pace yourself can help you maintain a consistent level of energy, accomplish just as much and feel better emotionally.
• Acknowledge your emotions. Denial, anger and frustration are normal feelings when you must deal with an illness. Things don't seem normal or fair and likely seem out of your control. Feelings of fear and isolation are common, so stay close to your family and friends. Try to maintain your daily routine as best you can and don't neglect doing those things you enjoy. Many people find support groups to be a helpful resource.

Source: http://www.mayoclinic.com