Anti neutrophil cytoplasm antibodies (ANCA)

Sharing is caring!

What are Anti neutrophil cytoplasm antibodies (ANCA)?

Kidney biopsies from patients with type III RPGN have no immune deposits, but type III RPGN usually results from small-vessel vasculitides associated with circulating Anti neutrophil cytoplasm antibodies.

The Anti neutrophil cytoplasm antibodies -associated small vessel vasculitides are:

• Granulomatosis with polyangiitis (GPA, formerly Wegener’s granulomatosis)

• Microscopic polyangiitis (MPA; systemic and kidney-limited)

• Eosinophilic granulomatosis with polyangiitis (EGPA, formerly known as Churg-Strauss syndrome)

These are usually systemic diseases but can be limited to the kidney. ANCA are directed against neutrophil proteinase 3 (PR3) or myeloperoxidase (MPO). Screening for Anti neutrophil cytoplasm antibodies uses an indirect immunofluorescence examination of normal neutrophils, which, if positive, demonstrates a staining pattern characteristic of the target antigen (cytoplasmic for ANCA [C-ANCA] against PR3 and perinuclear for anti-MPO ANCA [P-ANCA]).

The P-ANCA screening test has low specificity because other anti-neutrophil antibodies give a similar pattern by indirect immunofluorescence. A screening test that is positive for either C-ANCA or P-ANCA needs confirmation with an antigen-specific technique. C-ANCA positivity is associated with active GPA, and P-ANCA positivity is associated with active MPA and less so EGPA.

However, ANCA testing results have to be interpreted in the context of the clinical presentation, and the diagnosis of a vasculitis or glomerulonephritis often requires a tissue biopsy.

Anti neutrophil cytoplasm antibodies antibodies can be present in patients with non-vasculitic rheumatologic diseases, infections, and autoimmune gastrointestinal diseases, and can co-occur with other types of acute glomerulonephritis (e.g., anti-GBM disease).

Sharing is caring!

You cannot copy content of this page


Sign up to receive the trending updates and tons of Health Tips

Join SeekhealthZ and never miss the latest health information

Scroll to Top