Overlap between dermatomyositis and ANCA vasculitides.

We present the second report of the association between antineutrophil cytoplasm antibodies (ANCA)-associated vasculitis with dermatomyositis (DM). A 47-year-old woman suddenly developed rapidly progressive renal failure in the context of (DM). The kidney biopsy showed focal and segmental necrotizing glomerulonephritis with crescent formation. Cyclophosphamide treatment was commenced resulting in a significant recovery of kidney function and maintenance of recovery at 6 months. Although the pathophysiology is unknown, we hypothesize that CD8-T-deficient cells and MPO+ neutrophils in the DM lesions play an important role in the disease process.