Antibodies to skeletal muscles
Skeletal muscle antibodies (SMA) are autoantibodies produced by the immune system against components of striated (skeletal) muscles. Normally, these antibodies are not present in the body. Their appearance indicates a disruption of immune tolerance, in which the immune system begins to attack its own muscle tissue, perceiving it as foreign.
Antibodies to skeletal muscles are most often produced in autoimmune diseases, especially those accompanied by inflammatory muscle damage or involvement of muscle tissue in a systemic inflammatory process.
These conditions include:
- Autoimmune myopathies:
- Polymyositis;
- Dermatomyositis;
- Necrotizing autoimmune myopathy;
- Myasthenia gravis and other neuromuscular diseases;
- Chronic inflammatory liver diseases, in particular type 1 autoimmune hepatitis (more common in children and young women);
- Paraneoplastic syndromes - in response to the presence of a malignant tumor in the body