Diagnosis and risk stratification in patients with anti-RNP autoimmunity.

Introduction: Anti-RNP autoantibodies occur either in mixed connective tissue disease (MCTD) (with a frequently favorable prognosis), or in systemic lupus erythematosus (SLE) cases with aggressive major organ disease. It is uncertain how to assess for the risk of severe disease in anti-RNP + patients.

Methods: Following institutional review board-approved protocols, clinical data and blood were collected from patients with known or suspected anti-RNP autoimmunity and normal controls in a cohort study.