Special Precautions/Comments:

Method: EliA performed on Phadia Immunocap 250. Calibration: Calibrated against WHO IgG reference. preparation (IRP) 67/086. EQA scheme: UK NEQAS scheme for Neutrophil Cytoplasmic and GBM antibodies. IQC: Commercial preparation

Interferences: None known

Interpretation: NORMAL result is NEGATIVE. Results are to be reported as follows: NEGATIVE Result: <3.5 IU/mL. POSITIVE Result: >3.5 IU/mL

Additional Information:

See PR3 for more specific information on this analyte’

Indication: Screening test for small vessel vasculitis. Seen particularly in Wegener’s granulomatosis (WG), microscopic polyangitis (MPA) and its renal limited variant (pauci-immune crescentic glomerulonephritis) and Churg-Strauss syndrome.

Background Information: P-ANCA are principally directed against myeloperoxidase (MPO), which is found in azurophil granules in the cytoplasm of human neutrophils. Other P-ANCA antigen specificities are for elastase and lactoferrin. P-ANCA is associated in MPA and in some cases of WG and Churg-Strauss syndrome although can also be seen in inflammatory bowel disease and other autoimmune diseases [2]. ANCA measurements are not closely associated with disease activity and should therefore not determine treatment increases or decreases [1]. However treatment withdrawal in patients with a persistently positive ANCA is associated with relapse [1].

References: Guilpain P, et al. Natural and disease associated anti-myeloperoxidase (MPO) antibodies. Autoimmunity Reviews. 2008. 7(6):421-425. Lapraik C, et al. BSR and BHPR guidelines for the management of adults with ANCA associated vasculitis. Rheumatology. 2007. 46(10): 1615-1616. [Ref 1] Bosch X, Guilabert A and Font J. Antineutrophil cytoplasmic antibodies. Lancet. 2006. 368(9533):404-418. Seo P and Stone J. The Antineutrophil cytoplasmic antibody-associated vasculitides. Am J Med. 2004. 117:39-50. Reumaux D, Duthilleul P, Roos D. Pathogenesis of diseases associated with antineutrophil cytoplasm autoantibodies. Hum Immunol. 2004. 65(1):1-12. Savige J, et al. Addendum to the International Consensus Statement on testing and reporting of antineutrophil cytoplasmic antibodies. Quality control guidelines, comments, and recommendations for testing in other autoimmune diseases. Am J Clin Pathol. 2003. 120(3):312-318. Review. [Ref 2]

See Also: ANCA; PR3

Telephone Gateshead Lab: 0191.4456499 Option 4, Option 1