This site is intended for healthcare professionals

Go to /sign-in page

You can view 5 more pages before signing in

MPO-ANCA

Last reviewed dd mmm yyyy. Last edited dd mmm yyyy

Authoring team

  • two ANCA patterns were originally identified by indirect immunofluorescence (IIF): the cytoplasmic (C-ANCA) and the perinuclear (P-ANCA) patterns
    • 'classical' P-ANCA pattern is associated with antibodies to myeloperoxidase (MPO), a 140 kDa heterodymeric enzyme also associated with the antimicrobial properties of neutrophils
    • if IIF and ELISA results are combined, the presence of P-ANCA and anti-MPO has 99% specificity for the diagnosis of primary systemic vasculitis, as does the combination of C-ANCA and anti- PR3
    • P-ANCA and anti-MPO are more often seen in microscopic polyangitis (MPA), Churg-Strauss Syndrome (CSS) and idiopathic necrotising glomerulonephritis
      • in the context of vasculitis, C-ANCA in more than 90% of cases is directed against PR3, whereas in 80-90% of cases P-ANCA reacts with MPO
      • although C-ANCA (anti-PR3) is predominately associated with Wegener's Granulomatosis (WG) and P-ANCA (MPO) with MPA and CSS, there is no absolute specificity
        • between 10 and 20% of patients with classical WG demonstrate P-ANCA and anti-MPO and an even larger number of patients with MPA or CSS have C-ANCA and anti-PR3

Notes:

  • 10-20% of patients with WG or MPA and 45-50% of CSS have negative ANCA results

Reference:

  1. ARC. Topical Reviews - Rheumatic Diseases: Serological Aids to Early Diagnosis. February 2006.

Related pages

Create an account to add page annotations

Annotations allow you to add information to this page that would be handy to have on hand during a consultation. E.g. a website or number. This information will always show when you visit this page.

The content herein is provided for informational purposes and does not replace the need to apply professional clinical judgement when diagnosing or treating any medical condition. A licensed medical practitioner should be consulted for diagnosis and treatment of any and all medical conditions.

Connect

Copyright 2024 Oxbridge Solutions Limited, a subsidiary of OmniaMed Communications Limited. All rights reserved. Any distribution or duplication of the information contained herein is strictly prohibited. Oxbridge Solutions receives funding from advertising but maintains editorial independence.