Diane Safer, PhD
Polymyositis is a rare disease of the muscles. It usually affects the muscles closest to the trunk of the body. However, it may affect muscles anywhere in the body. The muscles become inflamed or swollen. This causes pain. The disease is progressive and starts slowly. If untreated, the muscles gradually become weaker. The pain in the muscles also increases.
Polymyositis may be caused by a combination of genetic and environmental factors that trigger an abnormal immune response.
Polymyositis is more common in women, and in people aged 31-60 years old.
Polymyositis may cause:
This diagnosis is not easy. Symptoms vary from person to person. It is often a matter of ruling out other diseases and conditions. Your doctor will ask about your symptoms and medical history. A physical exam will be done.
Tests may include the following:
Imaging tests take pictures of internal body structures to look for muscle inflammation. This can be done with an
While there is no cure, treatment can improve your muscle strength and function. Talk with your doctor about the best plan for you. Options include:
Medications to treat polymyositis may include:
is another treatment option. It involves using an IV needle to inject extra immunoglobins (special proteins) into the body. This process may help the immune system function better and reduce inflammation.
Your doctor may recommend that you work with a physical therapist to prevent permanent muscle damage. Exercise may include:
Polymyositis can lead to problems with chewing and swallowing. By working with a registered dietitian, you can learn ways to adjust to these changes and get the nutrition that you need.
Polymyositis may also cause speech problems. A speech therapist can assess your condition and create a program for you.
There are no current guidelines to prevent polymyositis.
American Autoimmune Related Diseases Association
The Myositis Association
The Arthritis Society
Choy EH, Hoogendijk JE, Lecky B, Winer JB, Gordon P. Immunosuppressant and immunomodulatory treatment for dermatomyositis and polymyositis.
Cochrane Database Syst Rev. 2009;(4):CD003643.
Idiopathic inflammatory myopathy: treatment. EBSCO DynaMed website. Available at:
http://www.ebscohost.com/dynamed/what. Updated April 7, 2013. Accessed July 31, 2013.
Myositis. American Academy of Orthopaedic Surgeons Ortho Info website. Available at:
http://orthoinfo.aaos.org/topic.cfm?topic=A00198. Updated July 2007. Accessed July 31, 2013.
Getting diagnosed. The Myositis Association website. Available at:
http://www.myositis.org/learn-about-myositis/diagnosis. Updated March 2012. Accessed July 31, 2013.
Myositis Association. Myositis FAQ. Myositis Association website. Available at:
http://www.myositis.org/learn-about-myositis/types-of-myositis. Updated March 2012. Accessed July 31, 2013.
Treatment. Myositis Association website. Available at:
http://www.myositis.org/learn-about-myositis/treatment. Updated March 2012. Accessed July 31, 2013.
NINDS Polymyositis information page. National Institute of Neurological Disorders and Stroke website. Available at:
http://www.ninds.nih.gov/disorders/polymyositis/polymyositis.htm. Updated August 26, 2011. Accessed July 31, 2013.
Simply stated: the creatine kinase test.
Last reviewed June 2013 by John C. Keel, MD
Please be aware that this information is provided to supplement the care provided by your physician. It is neither intended nor implied to be a substitute for professional medical advice. CALL YOUR HEALTHCARE PROVIDER IMMEDIATELY IF YOU THINK YOU MAY HAVE A MEDICAL EMERGENCY. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with any questions you may have regarding a medical condition.
Copyright © EBSCO Publishing. All rights reserved.