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Polymyositis is a systemic connective tissue disease characterized by inflammation and degeneration of the muscles

Information about Polymyositis

The cause of this disorder is unknown. It is thought that an autoimmune reaction or a viral infection of the skeletal muscle may cause the disease. It can affect people at any age, but most commonly occurs in those between 50 and 70 years old, or in children between 5 and 15 years old. It affects women twice as often as men.

Muscle weakness may appear suddenly or occur slowly over weeks or months. There may be difficulty raising the arms over the head, rising from a sitting position, or climbing stairs. The voice may be affected through weakness of the throat muscles. Joint pain, inflammation of the heart, and lung disease may occur.

A similar condition, called dermatomyositis, is evident when a dusky, red rash appears over the face, neck, shoulders, upper chest, and back. A malignancy may be associated with this disorder. Each year, between 2 and 10 people per million develop the disease.

Causes of Polymyositis

The cause of PM and DM is not known, but it is suspected that a variety of factors may play a role in the development of these diseases. PM and DM may be autoimmune diseases, caused by the immune system's attack on the body's own tissue. The reason for this attack is unknown, although some researchers believe that a combination of immune system susceptibility and an environmental trigger may explain at least some cases. Known environmental agents associated with PM and DM include infectious agents such as Toxoplasma, Borrella (Lyme disease bacterium), and coxsackievirus. Most cases, however, have no obvious triggers (direct causative agents). There may also be a genetic component in the development of PM and DM.

Symptoms of Polymyositis

  • muscle weakness, proximal muscles (shoulders, hips, etc.)
  • muscle pain
  • difficulty swallowing
  • shortness of breath
  • hand tremor

The early symptoms of PM and DM are slowly progressing muscle weakness, usually symmetrical between the two sides of the body. PM and DM affect primarily the muscles of the trunk and those closest to the trunk, while the hands, feet, and face usually are not involved. Weakness may cause difficulty walking, standing, and lifting objects. Rarely, the muscles of breathing may be affected. Weakness of the swallowing muscles can cause difficulty swallowing (dysphagia). Joint pain and/or swelling also may be present. Later in the course of these diseases, muscle wasting or shortening (contracture) may develop in the arms or legs. Heart abnormalities, including electrocardiogram (ECG) changes and arrhythmias, develop at some time during the coursed of these diseases in about 30% of patients.

Dermatomyositis is marked by a skin rash. The rash is dusky, reddish, or lilac in color, and is most often seen on the eyelids, cheeks, bridge of the nose, and knuckles, as well as on the back, upper chest, knees, and elbows. The rash often appears before the muscle weakness.

Diagnosis of Polymyositis

PM and DM are often difficult diseases to diagnose, because they are rare, because symptoms come on slowly, and because they can be mistaken for other diseases causing muscle weakness, especially limb girdle muscular dystrophy.

Accurate diagnosis involves:

  • A neurological exam.
  • Blood tests to determine the level of the muscle enzyme creatine kinase, whose presence in the circulation indicates muscle damage.
  • Electromyography, an electrical test of muscle function.
  • Muscle biopsy, in which a small sample of affected muscle is surgically removed for microscopic analysis. A biopsy revealing muscle cells surrounded by immune system cells is a strong indicator of myositis.

Treatment of Polymyositis

The disease is treated with corticosteroid medications. When an improvement in muscle strength is achieved, usually in 4 to 6 weeks, the medication is slowly tapered off. Maintenance therapy with prednisone may be continued indefinitely. In people who fail to respond to corticosteroids, medications to suppress the immune system may be used.

If the condition is associated with a tumor, the condition may improve if the tumor is removed.

Alternative treatment of Polymyositis

As with all autoimmune conditions, food allergies/intolerances and environemental triggers may be contributing factors. For the food allergies and intolerances, an elimination/challenge diet can be used under the supervision of a trained practitioner, naturopath, or nutritionist, to identify trigger foods. These foods can then be eliminated from the person's diet. For environmental triggers, it is helpful to identify the source so that it can be avoided or eliminated. A thorough detoxification program can help alleviate symptoms and change the course of the disease. Dietary changes from processed foods to whole foods that do not include allergen trigger foods can have significant results. Nutrient supplements, especially the antioxidants zinc, selenium, and vitamins A, C, and E, can be beneficial. Constitutional homeopathic treatment can work at a deep level to rebalance the whole person. Acupuncture and Chinese herbs can be effective in symptom alleviation and deep healing. Visualization, guided imagery, and hypnosis for pain management are also useful.

Prognosis of Polymyositis

Remission (a period when no symptoms are present) and recovery occur in many patients, especially children. For most others, immunosuppressant drugs can control the disease. In adults, death may result from severe and prolonged muscle weakness, malnutrition, pneumonia, or respiratory failure. The probable outcome is usually worse if there is chest involvement.

Complications of Polymyositis

  • associated malignancy
  • heart disease, lung disease, or abdominal complications
  • calcium deposits in the affected muscles, especially in children with the disease





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