87261 – ANCA IFA dual

Intended Purpose

The ANCA IFA dual is an immunofluorescence assay (IFA) for the qualitative and semi-quantitative determination of IgG antibodies in human serum against neutrophil cytoplasmatic antigens (ANCA) on ethanol and formalin fixed human granulocytes. The ANCA IFA dual is intended as an aid in the diagnosis of systemic vasculitis (SV) in conjunction with other clinical and laboratory findings. The immunoassay is designed for manual professional in vitro diagnostic use only.

Diagnostic Relevance

The appearance of autoantibodies directed against components of the cell nucleus are characteristic features of systemic autoimmune diseases, especially; systemic lupus erythematosus (SLE), Sjögren’s syndrome, progressive systemic sclerosis (PSS), mixed connective tissue disease (MCTD), rheumatoid arthritis (RA) and dermatomyositis.  The detection of auto-antibodies in patient sample, e.g. plasma and serum, is well established and plays an essential role in the diagnosis of systemic autoimmune diseases. Systemic vasculitis (SV) pathogenesis is majorly identified by the inflammation of different blood vessel walls, and the resulting morphological changes. Arteries and veins can both be affected simultaneously. The clinical manifestation is mainly indicated by general symptoms like exhaustion, fever and weight loss. Depending on which kind of vessels are affected, future disease course varies.

Anti-neutrophil cytoplasmic antibodies (ANCA) play an essential role in the serological diagnosis of SV. These antibodies are usually determined by indirect immunofluorescence using ethanol fixed human neutrophils. Cytoplasmic ANCA (cANCA) and perinuclear ANCA (pANCA) are distinguished based on the immunofluorescence pattern. Cell fixation using ethanol destroys granular membranes in neutrophil cytoplasm, thus allowing positively charged proteins move to the negatively charged nucleus – the basis for ANCA screening substrate. cANCA antibodies are identified by a cytoplasmic fluorescence pattern, whereas pANCA antibodies must be differentiated from antibodies to nuclear antigens (ANA) which also show a (peri) nuclear pattern. GA Generic Assays pANCA IFA plus is used for the confirmation of pANCA positive results found on ethanol fixed granulocytes.