肌性动脉有慢性炎性细胞浸润的血管炎存在。可见血管内皮细胞增生以及管腔消失。通常，血管炎是自身免疫性疾病的特征性表现，如本例病人就患有系统性红斑狼疮。血管炎是罕见的而且它形态的多样性容易造成混淆，从而难以诊断和区分。测试抗核抗体和抗中性粒细胞抗体可帮助诊断。
This muscular artery demonstrates vasculitis with chronic inflammatory cell infiltrates. The endothelial cells have proliferated and the lumen is absent. Often, vasculitis is a feature of an autoimmune disease, such as systemic lupus erythematosus as was present in this patient. Vasculitis is uncommon and the various forms are confusing and difficult to diagnosis and classify. Tests such as ANA and ANCA help.