Dermatomyositis: focus on cutaneous features, etiopathogenetic mechanisms and their implications for treatment

Abstract

Dermatomyositis (DM) is an infrequently encountered idiopathic inflammatory myopathy distinguished by distinctive cutaneous manifestations and/or progressive muscle weakness. This review provides an updated exploration of DM, emphasizing cutaneous features, etiopathogenesis, and therapeutic implications. DM presents a heterogeneous spectrum, ranging from classic forms involving both skin and muscle to clinically amyopathic DM, which lacks significant muscle involvement but carries risks like interstitial lung disease (ILD) and malignancy. Recent advances in understanding DM pathogenesis underscore the roles of myositis-specific autoantibodies, type I interferons, and cytokine dysregulation in disease activity and clinical outcomes. Specific antibodies such as anti-Mi-2, anti-TIF1γ, and anti-MDA5 define subtypes of DM, aiding diagnosis, prognosis, and tailored management strategies. While conventional immunosuppressive therapies like glucocorticoids and antimalarials form the cornerstone of treatment, many cases remain refractory, particularly involving chronic skin disease. Emerging targeted therapies, including Janus kinase inhibitors and monoclonal antibodies, show promise in addressing type I interferon-driven pathways and refractory symptoms. Future research aims to refine diagnostic criteria, integrate biomarkers, utilize more robust outcome measures, and develop targeted therapeutics to improve outcomes while minimizing treatment-related toxicity. This review consolidates current knowledge and highlights the need for a multidisciplinary, individualized approach to managing DM, focusing on both established and novel treatment avenues.

Keywords: Amyopathic dermatomyositis; Cutaneous manifestations of dermatomyositis; Dermatomyositis; Etiology of dermatomyositis; Pathogenetic mechanisms for dermatomyositis; Treatments for dermatomyositis.