Are there any other MSAs that will be helpful in categorizing the Idiopathic Inflammatory Myopathies?
It is likely that other MSAs will be discovered to help classify IIM and help predict clinical features, prognosis, and response to therapy. Recently, anti-four-and-a half LIM domain 1 (FHL1) has been reported to identify patients with PM, DM, or IBM who have a particularly severe myositis with muscle atrophy, dysphagia, and vasculitis. FHL1 is a muscle-specific protein. Patients with IIM who have this MSA do not have other MSAs.