DISEASES
description
Autoimmune myositis (AIM) is a group of uncommon diseases that primarily involves the skeletal muscles. These diseases include polymyositis, anti-synthetase syndrome, dermatomyositis, juvenile dermatomyositis, inclusion body myositis, necrotizing myopathy and overlap syndromes such as mixed connective tissue disease and scleromyositis. The main symptom is progressive muscle weakness, especially of the muscles closest to the torso. Each AIM subset is associated with a unique autoantibody biomarker that can help the physician make an accurate diagnosis and initiate appropriate treatment. A small proportion of AIM patients have or eventually develop cancer and several autoantibodies are associated with a higher risk of cancer.
Symptoms
- Trouble rising from a chair
- Difficulty climbing stairs or lifting arms
- Tired feeling after standing or walking
- Trouble swallowing or breathing
- Muscle pain and soreness that does not resolve after a few weeks
- Known elevations in muscle enzymes by blood tests (CPK or aldolase)
- Rashes
- Weight loss
- Low-grade fever
- Inflamed lungs
- Light sensitivity
- May accompany tumors of the breast, lung, female genitalia, or bowel (Adult dermatomyositis)
- Calcinosis (calcium deposits, which appear as hard bumps under the skin or in the muscle)
Relevant Dx Tests
- Autoimmune Myopathy / Myositis Panel PLUS
- Anti-SMN / GEMIN1 / RuvBL1/B2
- Anti-Nuclear Envelope / Membrane Panel