International Consensus Statement on Testing and Reporting of Antineutrophil Cytoplasmic Antibodies (ANCA)

Am J Clin Pathol. 1999 Apr;111(4):507-13. doi: 10.1093/ajcp/111.4.507.


Antineutrophil cytoplasmic antibody (ANCA) tests are used to diagnose and monitor inflammatory activity in the primary systemic small vessel vasculitides. ANCA is best demonstrated in these diseases by using a combination of indirect immunofluorescence (IIF) of normal peripheral blood neutrophils and enzyme-linked immunosorbent assays (ELISAs) that detect ANCA specific for proteinase 3 (PR3) or myeloperoxidase (MPO). For ANCA testing in "new" patients, IIF must be performed on all serum samples. Serum samples containing ANCA, any other cytoplasmic fluorescence, or an antinuclear antibody (ANA) that results in homogeneous or peripheral nuclear fluorescence then should be tested in ELISAs for PR3-ANCA and MPO-ANCA. Optimally, ELISAs for PR3-ANCA and MPO-ANCA should be performed on all serum samples. Inclusion of the most recent positive sample in the IIF or ELISA may help demonstrate a change in antibody level. Reports should use recommended terms. Any report of positive neutrophil fluorescence issued before the ELISA results are available should indicate that positive fluorescence alone is not specific for the diagnosis of Wegener granulomatosis or microscopic polyangiitis and that decisions about treatment should not be based solely on the ANCA results.

Publication types

  • Consensus Development Conference
  • Guideline
  • Practice Guideline
  • Review

MeSH terms

  • Antibodies, Antineutrophil Cytoplasmic / blood*
  • Antibodies, Antinuclear / blood
  • Churg-Strauss Syndrome / diagnosis
  • Enzyme-Linked Immunosorbent Assay / standards
  • Fluorescent Antibody Technique, Indirect / standards
  • Glomerulonephritis / diagnosis
  • Granulomatosis with Polyangiitis / diagnosis
  • Humans
  • Myeloblastin
  • Neutrophils / immunology
  • Peroxidase / immunology
  • Quality Control
  • Reference Values
  • Sensitivity and Specificity
  • Serine Endopeptidases / immunology
  • Terminology as Topic
  • Vascular Diseases / diagnosis*
  • Vasculitis / diagnosis


  • Antibodies, Antineutrophil Cytoplasmic
  • Antibodies, Antinuclear
  • Peroxidase
  • Serine Endopeptidases
  • Myeloblastin