The aetiopathogenic significance, clinical relevance and therapeutic implications of vasculopathy in idiopathic inflammatory myopathy

It is 120 years since 'angiomyositis' was included alongside 'polymyositis' and 'dermatomyositis' in an attempt to propose a taxonomy that reflected the major clinical characteristics of idiopathic inflammatory myopathy (IIM). Endothelial injury, perivascular inflammation and capillary loss are important histological findings in affected tissues in IIM. Overt vascular clinical features including RP and abnormal nailfold capillaroscopy (NC) are also common in IIM. Despite the presence of endothelial injury, perivascular inflammation and capillary loss in affected tissues in IIM, and the presence of clinical features such as RP and NC abnormalities, the pathogenic and therapeutic implications of vasculopathy in IIM have been somewhat overlooked. RP and NC abnormalities are not always present, providing a valuable opportunity to explore aetiopathogenic factors driving vasculopathy within autoimmune rheumatic disease. The present review examines the aetiopathogenic, prognostic and therapeutic significance of vasculopathy in IIM. We describe the prevalence and clinical relevance of vasculopathy in IIM, and consider how vasculopathy may be better utilized to support improved IIM diagnosis and disease classification. Areas of unmet research need are highlighted where relevant.