Current and Emerging Biomarkers in Dermatomyositis: Clinical Utility and Future Directions

Idiopathic inflammatory myopathies (IIM) comprise a heterogeneous group of autoimmune disorders with variable systemic involvement. Among them, dermatomyositis (DM) is the subtype with the most extensive biomarker characterization due to its defined immunopathology and frequent association with interstitial lung disease (ILD). This narrative review summarizes studies retrieved from PubMed, Scopus, and Web of Science up to March 2025, focusing on non-autoantibody biomarkers in DM. Reported categories include soluble proteins, cytokines, chemokines, muscle-specific microRNAs, and transcriptomic signatures reflecting interferon activation, tissue injury, and fibrotic remodeling. Among the most validated molecules, interferon-stimulated genes, ferritin, KL-6, SP-D, and CXCL10 demonstrate diagnostic and prognostic value, particularly in anti-MDA5-positive DM, where they support early identification of patients at risk for rapidly progressive ILD. However, despite increasing evidence, most biomarkers lack disease specificity, standardized cutoffs, and multicenter validation, while molecular assays remain confined to specialized laboratories. Clinically accessible markers such as ferritin, KL-6, and CXCL10 currently offer the highest translational potential. Nevertheless, the heterogeneity of study designs and analytical methods continues to limit comparability and routine clinical integration. Future research should prioritize the validation of composite biomarker panels through standardized, multicentric studies to enhance diagnostic precision and enable precision medicine approaches in DM and related inflammatory myopathies.