Anti-RuvBL1/2 Antibodies in Scleromyositis: A Clinicopathological Report of Two Cases.

We report two patients with scleromyositis with anti-RuvBL1/2 antibodies, recently identified rare autoantibodies associated with older age at onset, diffuse sclerodactyly, skeletal and cardiac myositis, and interstitial lung disease (ILD). Both patients showed sclerodactyly and skeletal myositis. Muscle biopsy revealed lymphocytes and macrophage infiltration in an 83-year-old woman with cardiac involvement and immune-mediated necrotizing myopathy in a 68-year-old woman with ILD, guiding diagnosis and treatment decisions. Glucocorticoids and immunosuppressants led to clinical improvement. These cases highlight the clinical and pathologic spectrum of anti-RuvBL1/2 antibody-associated disease and the value of antibody detection and tissue analysis.