Familial occurrence of systemic vasculitis and rapidly progressive glomerulonephritis

Two familial clusters of systemic vasculitis are described. In one family, microscopic polyangiitis and rapidly progressive glomerulonephritis occurre d in HLA-identical siblings; in the second family, 3 second- and fourth-deg ree related members were affected by Wegener's granulomatosis. Published cl usters of systemic vasculitides and Goodpasture's syndrome are reviewed, an d, together with the observed families, the evidence for genetic susceptibi lity and a causative role of environmental factors for these diseases with special emphasis on the HLA system is discussed. (C) 1999 by the National K idney Foundation, Inc.