Overlap syndrome in a 12-year-old girl with systemic lupus erythematosus and anti-oj antibody-positive polymyositis: a case report.

Overlap syndrome with inflammatory myositis can occur years later in pediatric SLE cases. We should be alert when patients with SLE develop a new presentation characterized by decreased SLE-specific autoantibody titers, positive anti-RNP antibodies, and elevated CPK. Treatment of the overlap syndrome of SLE and JPM is individualized, and the course differs between pediatric and adult patients.