Inflammation of the muscles and associated tissues, affecting the skeletal muscles that control movement.

Common Symptoms

Limited ability or inability to walk, run, and lift oneself up, difficulty swallowing, shortness of breath, and muscle aches. Symptoms typically start in the proximal (nearer to the center of the body or point of attachment, such as the elbow) muscles and progress to the distal (away from the center of the body or from the point of attachment) muscles.

Coexisting Diseases and Conditions

Systemic lupus erythematosus, rheumatoid arthritis, scleroderma, Raynaud’s phenomenon, interstitial lung disease, cardiovascular disease, and Sjogren’s syndrome.

Risk Factors and Prevalence

Polymyositis typically occurs after the age of 20, affects more females than males, and can develop following viral infections such as HIV/AIDS.


  1. Article Sources
    1. Polymyositis. (n.d.-a). The Myositis Association. Retrieved June 12, 2021, from https://www.myositis.org/about-myositis/types-of-myositis/polymyositis/

    2. Polymyositis: Symptoms, Causes & Treatments. (n.d.-b). Cleveland Clinic. Retrieved June 12, 2021, from https://my.clevelandclinic.org/health/diseases/12053-polymyositis

    3. Polymyositis—Symptoms and causes. (n.d.). Mayo Clinic. Retrieved June 12, 2021, from https://www.mayoclinic.org/diseases-conditions/polymyositis/symptoms-causes/syc-20353208

    4. Sarwar, A., Dydyk, A. M., & Jatwani, S. (2021). Polymyositis. In StatPearls. StatPearls Publishing. http://www.ncbi.nlm.nih.gov/books/NBK563129/