Myositis/Polymyositis

Myositis is a group of rare inflammatory diseases that cause inflammation of the muscles, leading to muscle weakness and, in some cases, pain and fatigue.

Polymyositis is one type of myositis in which the immune system mistakenly attacks skeletal muscles, the muscles responsible for voluntary movement, resulting in progressive muscle weakness, particularly in the shoulders, hips, and trunk.

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.

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

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

• Prevalence of interstitial lung disease in polymyositis and dermatomyositis: A meta-analysis from 2000 to 2020 (2021)
• Polymyositis: does it really exist as a distinct clinical subset? (2021)
• Polymyositis: is there anything left? A retrospective diagnostic review from a tertiary myositis center (2021)
• Risk prediction modeling based on a combination of initial serum biomarker levels in polymyositis/dermatomyositis– associated interstitial lung disease (2020)