Update on autoantibodies and related biomarkers in autoimmune inflammatory myopathies

PURPOSE OF REVIEW: This manuscript reviews recently published advances in the identification of autoimmune inflammatory myopathies (AIM)-specific and AIM-related autoantibodies considered of value in the workup of patients suspected of having AIM. Newer autoantibodies, developments, and advances in the methodology of testing, the gaps and pitfalls in using these assays as diagnostic biomarkers, and the importance of considering overlap diseases and unique clinical AIM phenotypes are discussed. RECENT FINDINGS: a).. studies of the various diagnostic platforms (e.g., line immunoassays [LIA]) have clarified their limitations and raise cautions in the interpretation of the results. b).. particle based solid phase multianalyte technology (PMAT) is a promising newer diagnostic platform. c).. elucidation of older and descriptions of newer AIM autoantibody markers provide increasing clinical value by revealing novel clinical features (including AIM subsets and overlap syndromes [OS]) and co-existing malignancies. SUMMARY: The spectrum of autoantibodies and related biomarkers in AIM continues to expand. Many of these have clear clinical implications in regard to subsets and overlap conditions of AIM, associated malignancy and pathological findings.