[Dermatomyositis].

Dermatomyositis is a heterogeneous disorder that can be classified into more homogeneous subsets. Autoantibodies are a useful tool in identifying such subsets because they correlate strongly with clinical phenotypes. In dermatomyositis, five disease-specific autoantibodies have been established to date, including antiMi-2, anti-melanoma differentiation-associated gene 5, anti-transcriptional intermediary factor 1, anti-nuclear matrix protein 2, anti-transcriptional intermediary factor 1, and anti-small-ubiquitin-like activating enzyme antibodies. In addition, several novel autoantibodies have recently been demonstrated in patients with dermatomyositis, including anti-four-and-a-half-LIM-domain 1, anti-cell division cycle and apoptosis regulator protein 1, anti-specificity protein 4, anti-cortactin, and IgM anti-angiotensin converting enzyme 2 antibodies.