A comparison of commercial and in-house ELISAs for antineutrophil cytoplasmic antibodies directed against proteinase 3 and myeloperoxidase

Pathology. 1999 Feb;31(1):38-43. doi: 10.1080/003130299105511.


This study compares the concordance of results in different ELISAs for antineutrophil cytoplasmic antibodies (ANCA) directed against proteinase 3 (PR3) or myeloperoxidase (MPO). Sera were considered "true positives" if they were positive according to the manufacturer's criteria in a least three of the five PR3-ANCA ELISAs, or in at least four of the six MPO-ANCA ELISAs. Of the 26 sera that demonstrated cytoplasmic fluorescence (C-ANCA), 23 (89%) contained PR3-ANCA and three (11%) had MPO-ANCA. Two sera that were negative by indirect immunofluorescence (IIF) contained PR3-ANCA. Of the 26 sera with perinuclear fluorescence (P-ANCA), 19 (73%) contained MPO-ANCA, and one (4%) had PR3-ANCA. Six sera with P-ANCA did not have PR3- or MPO-ANCA. No serum that was negative by IIF contained MPO-ANCA. For the different PR3-ANCA ELISAs, sensitivities ranged from 88 to 100%, and specificities from 91 to 100%. For the MPO-ANCA ELISAs, sensitivities varied from 59 to 100% and specificities from 83 to 100%. The highest sensitivity and specificity for both the PR3- and MPO-ANCA ELISAs were obtained with the IBL and Eurodiagnostica assays. The in-house PR3-ANCA ELISA performed slightly less well than the commercial assays, but the performance of the in-house MPO-ANCA assay was comparable or better.

Publication types

  • Comparative Study

MeSH terms

  • Antibodies, Antineutrophil Cytoplasmic / blood*
  • Antibodies, Antineutrophil Cytoplasmic / immunology
  • Enzyme-Linked Immunosorbent Assay / instrumentation*
  • Fluorescent Antibody Technique, Indirect
  • Humans
  • Myeloblastin
  • Peroxidase / immunology*
  • Reagent Kits, Diagnostic*
  • Sensitivity and Specificity
  • Serine Endopeptidases / immunology*
  • Vasculitis / blood


  • Antibodies, Antineutrophil Cytoplasmic
  • Reagent Kits, Diagnostic
  • Peroxidase
  • Serine Endopeptidases
  • Myeloblastin