Clinical significance of anti-neutrophil cytoplasmic antibodies (ANCA) in collagen diseases associated with vasculitic syndrome in Japan.

The present study was undertaken to determine the anti-neutrophil cytoplasmic antibody (ANCA) levels in 96 patients with various collagen diseases associated with renal vasculitis and vasculitic syndrome in Japan. The results indicated that cytoplasmic(C)-ANCA is an autoantibody highly specific to Wegener's granulomatosis (WG) and that it is also active in renal injury. The relationships between ANCA and focal segmental necrotizing GN, i.e., renal vasculitis as proposed by Balow, were investigated. Perinuclear(P)-ANCA was detected with high sensitivity and specificity in renal vasculitis without WG, and the severity of necrotizing and crescentic nephritis in WG was correlated especially well with the C-ANCA titer. Detection of ANCA is considered clinically useful for the etiological differentiation of renal vasculitis, suggesting the possibility that C-ANCA may be involved in the onset of vasculitis of the glomerular capillary vessels in WG. The presence of C-ANCA and cytokines (IL-1 beta and TNF-alpha) is important in the pathogenesis of vasculitis and GN in WG.