Use

The idiopathic inflammatory myopathies (IIM) are a heterogeneous group of disorders characterized by muscle weakness, resulting from chronic muscle inflammation of unknown cause. Patients with IIM have a variety of autoantibodies with various clinical utilities that fall into two main groups. One group of autoantibodies are found in patients with myositis and are known as Myositis Specific Autoantibodies (MSA). The MSAs are highly specific for patients with polymyositis (PM) dermatomyositis (DM), anti-synthetase syndrome and necrotizing myositis. The second group of autoantibodies are considered Myositis Associated Autoantibodies (MAA). These appear in myositis overlap syndrome and in other connective tissue diseases, which correlate with certain clinical and/or pathophysiological conditions.