This muscular artery shows features of a vasculitis with chronic inflammatory cell infiltrates. The endothelial cells have proliferated and the lumen is obliterated. 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. Serologicc testing for ANA and ANCA may help diagnosis and distinguish the various forms of vasculitis.

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