Antibodies producing a perinuclear staining pattern are directed against different cytoplasmic constituents of neutrophils and are not specific for a single disease entity, but tend to be associated with disease groups which show several common clinical and histological features. pANCA occurs in such conditions as vasculitis, glomerulonephritis, Churg-Strauss syndrome, polyarteritis nodosa, SLE, RA and associated disorders (127).
A major antigen of pANCA is myeloperoxidase (MPO), which, with co-factors, constitutes a potent microbiocidal system within neutrophil granulocytes. Additional target antigens, such as human leukocyte elastase, lysozyme, cathepsin-G and lactoferrin have been associated with the pANCA f1uorescence pattern (128, 129) but in up to 50% of pANCA-positive sera, the target antigen(s) are unidentified. However, myeloperoxidase (MPO) antibodies are present in patients with pauci-immune glomerulonephritis who are negative for cANCA (130, 131), in patients with Churg-Strauss syndrome (132) and polyarteritis (133). Moreover, the determination of MPO-ANCA is recommended as prognostic marker (134). MPO-ANCA can also be induced by drugs such as hydralazine, clozapine and L-tryptophan (135, 136). Occupational exposure to environmental factors such as silica dust may provoke MPO-ANCA progressive glomerulonephritis.

Material Pattern: pANCA Substrate: Ethanol fixed Description Uniformly or rim-accentuated fluorescence of the nuclei of neutrophil granulocytes. Cytoplasm is free of decoration. For the diagnosis Formol-fixed preparations are necessary (DD.: Decoration by ANA!) Method Indirect immunoflourescence method.