New autoantibodies and their clinical associations in juvenile myositis - a systematic review.

Background: Novel autoantibodies targeting intracellular proteins are recently detected in patients with idiopathic inflammatory myopathies (IIMs).

Objective: To evaluate the prevalence of these myositis-specific antibodies (MSAs) in juvenile IIMs (JIIMs) and their association with clinical characteristics and disease course.

Methods: A systematic literature search was carried out to identify all studies concerning these novel MSAs (p155/140, p140, CADM-140, SAE and 200/100) in patients with JIIMs.

Results: A total of 1003 references were identified, of which 118 were selected for detailed analysis and 13 included in the final review.

Conclusions: The anti-p155/140, the anti-p140 and the anti-CADM-140 seem to be useful markers for define distinct clinical subsets and for predicting prognosis of JIIMs. Further studies are needed to clarify the importance of anti 200/100 and anti-SAE in juvenile myositis.