Systemic lupus erythematosus with necrotizing vasculitis and upregulated expression of VLA-4 antigen.

We report on a patient (S.A.), with well-defined SLE who developed a perforation of the ileum due to pathologically confirmed necrotizing vasculitis. No anti-DNA antibody was detected at the ileal perforation, and the serum complement level was normal. These findings raise the alternative possibility of a cell-mediated immune mechanism as a cause of necrotizing vasculitis. Upregulated expression and function of VLA-4 antigen on peripheral blood T cells were observed, suggesting that T cells with VLA-4 antigen may participate in the onset and/or perpetuation of vascular inflammation.