Abstract
A 54-year-old woman was referred to the Department of Internal Medicine for systemic lupus erythematosus (SLE) since 1976. She had been well-controlled with systemic prednisolone (PSL) 10mg daily for twenty-seven years. Two large indurated reddish nodules on her bilateral legs were noticed in 2002. A biopsy taken from one nodule confirmed the diagnosis of necrotizing vasculitis. Laboratory examinations found a high titer of myeloperoxidase antineutrophil cytoplasmic antibody (MPO-ANCA) and proteinase 3 antineutrophil cytoplasmic antibody (PR3-ANCA) accompanied by positive anti-nuclear, ds-DNA antibodies. This case was diagnosed as SLE with MPO-ANCA positive arteritis. PSL 30mg daily was administered, and the nodules rapidly disappeared. A case-control study was conducted in a cohort of 90 patients given a diagnosis of SLE in the National Hospital Organization Nagoya Medical Center Department of Dermatology. MPO- and PR3-ANCA were not detected separately in any of 90 SLE patients. Both MPO- and PR3-ANCA together were detected in one patient (our case). We suggest that MPO- and PR3-ANCA should be examined in patients with SLE-related necrotizing vasculitis.
