Polymyositis causes muscle weakness that can make it difficult to walk up stairwells or stand up from sitting positions, Merck Manual states. The condition commonly causes joint pain or muscle weakness in hips, thighs, upper arms, neck or shoulders. As core muscles close to the body's center are most susceptible, a person suffering from a severe case may be confined to a bed or wheelchair. Difficulty swallowing and raising the arms are possible symptoms, depending on the affected muscles.Continue Reading
Polymyositis is a chronic inflammatory disease that develops when an abnormal immune system reaction causes white blood cells to invade the muscle fibers, according to MedicineNet. The exact cause is unknown, and this progressive condition gradually worsens through a cycle of flare-ups and remissions. Persistent muscle weakness leads to a long-term loss of strength, and individuals may experience fatigue, weight loss, muscle tenderness or low-grade fever. When polymyositis affects areas of the upper body, the person may even struggle to lift her head from a pillow.
As a systemic condition, polymyositis can affect other areas of the body, such as skin, and it often develops in patients with other health problems, such as lupus, lymphoma and breast cancer, MedicineNet explains. Doctors typically use a long-term treatment of corticosteroids in high doses to relieve muscle inflammation, but patients who don't respond to this treatment may need immunosuppressive drugs to stop white blood cells from attacking muscle tissue.Learn more about Conditions & Diseases