Antineutrophil cytoplasm antibody (ANCA) associated vasculitis.

In 1982 we first reported the presence of antineutrophil cytoplasm antibodies (ANCA) in 8 patients with systemic vasculitis and segmental necrotizing glomerulonephritis. The results of long-term follow-up are described. Screening of 7,500 serum samples revealed positive ANCA in 9 additional patients with vasculitis. Eighty-eight other patients with vasculitis were ANCA negative, including 7 with microscopic polyarteritis nodosa (MPAN) and 8 with Wegener's granulomatosis (WG). Conversely, ANCA were never detected in the absence of vasculitis. Fourteen patients presenting with glomerulonephritis and ANCA were followed for a median of 6.3 years. Eleven patients had MPAN and 3 WG. Remissions were obtained with immunosuppressive therapy in all patients. Clinical relapse was associated with the reappearance of ANCA. Five-year survival was 89% and 5-year dialysis free survival was 77%. ANCA are specific markers for a sub-group of patients with vasculitis and are sensitive markers of disease activity. Glomerulonephritis associated with ANCA positive vasculitis has a favorable outcome with immunosuppressive therapy.