ANCA IIF

Indication

Suspicion of systemic vasculitis and inflammatory diseases.

Method

Indirect immunofluorescence (IIF)

Answer

The result is given as negative or positive with a titer.

Interpretation

The classical ANCA in systemic vasculitis is a reaction of IgG antibodies against granulocytes and is observed as a grainy staining of the granulocyte cytoplasm (C-ANCA) at the IIF investigation. C-ANCA occurs mainly in Wegener’s granulomatosis and other systemic vasculites, e.g. microscopic polyangiitis, Churg-Strauss syndrome, focal and extracapillary necrotizing glomerulonephritis. In active phases of the disease 90% of Wegener patients have C-ANCA. Another ANCA pattern is the perinuclear staining of granulocytes, the so-called P-ANCA, which also occurs in systemic vasculitis, more often in microscopic polyangiitis than in Wegener’s granulomatosis and above all when the disease is mainly located in the kidney. P-ANCA often occurs in inflammatory bowel disease, rheumatoid arthritis and drug induced SLE. It is worth noting that C- and P-ANCA are IIF patterns and may be caused by antibodies with different specificities against granule proteins. In case of positive IF it is therefore advisable to follow up with antigen specific ELISA analyses.

The IIF pattern can also be called atypical and is then more related to inflammatory diseases, such as UC, RA and not to vasculitis. If nuclear staining of other cells is observed in the investigation, it is called uncertain ANCA due to organ unspecific nuclear staining, since it is then not possible to know whether or not there is ANCA.

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Packages and other tests

View other packages ANCA for Systemic Vasculitis/anti-GBM Goodpastures syndrome (501), Drug induced lupus (541), Inflammatory bowel diseases (IBD) (513). View other tests MPO-ANCA (capture technique), MPO-ANCA (direct technique), PR3-ANCA (capture technique), PR3-ANCA (direct technique)

20 years experience