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Quality control of autoimmune diseases testing

Quality control of autoimmune diseases testing
©Henrik Dolle - Fotolia.com
Sep 13 2017

The JRC recently released a certified reference material  (CRM; ERM-DA476/IFCC) for testing of the immunoglobulin G proteinase 3 anti-neutrophil cytoplasmic autoantibodies (IgG PR3 ANCA).

The use of this CRM could lead to comparable, harmonised clinical testing results enabling the right diagnosis and treatment of the autoimmune disease small vessel associated vasculitis, a rare but often fatal disease.

There are more than 70 diseases resulting from the body's immune system targeting its organs, tissues, cells and their components. Many of these autoimmune diseases are characterised by the presence of different autoantibodies which are specific for each autoimmune disease.

Despite the importance of autoimmune antibodies in laboratory medicine and their routine analysis, the diversity in the measurement results from different methods remains vast. The immunoassays used for such measurements can be sensitive and specific and are convenient in a clinical setting.

However, the measurement signal is depending on a large number of factors such as antibody specificity, reaction kinetics and equilibria, multimeric state of the proteins, matrix effects, etc. The quantification with immunoassaystherefore requires the use of well-designed and carefully characterised calibrants. At present, even when calibrants are available, they are not fully characterised and inconsistently used.

This generates

  • a large variability in measurement results,
  • a potential delay in the diagnosis and subsequent treatment of the disease.

The JRC, in close collaboration with the International Federation of Clinical Chemists (IFCC), has now produced and certified the reference material ERM-DA476/IFCC, a material from a plasmapheresis sample of a patient diagnosed with vasculitis.

This CRM has the potential to reduce the variability between different methods and over time.

Read more in: E. Monogioudi et al.: "Development of a Certified Reference Material for myeloperoxidase-anti-neutrophil cytoplasmic autoantibodies (MPO-ANCA)", I. Clin. Chim. Acta 467 (2017 ) 48-50, doi:10.1016/j.cca.2016.05.031