Clinical Significance of Serum Levels of Anti‐Nuclear Matrix Protein 2 Antibodies in Patients With Dermatomyositis

Antinuclear matrix protein 2 (NXP-2) antibodies are dermatomyositis-specific antibodies that target NXP-2 involved in transcriptional regulation. However, their clinical significance and relationship with disease activity remain unclear. We performed a longitudinal examination on serum samples from three patients with dermatomyositis who tested positive for anti-NXP-2 antibodies. These serum samples were analyzed alongside clinical parameters, including disease activity, muscle enzyme levels, and treatment response. The levels of anti-NXP-2 antibodies and serum creatine kinase decreased with symptom improvement in all the cases. Anti-NXP-2 antibody levels showed a correlation with disease activity, suggesting their potential role as a marker of disease activity.