Six years of INSTAND e. V. sIgE proficiency testing: An evaluation of in vitro allergy diagnostics
- Wojtalewicz, N.
- Goseberg, S.
- Kabrodt, K.
- Schellenberg, I.
Veröffentlicht in: Allergo Journal, Volume 26, Issue 2, March 2017, Pages 20-29
Background: Even though allergies are an important health issue, wide manufacturer-dependent differences in the detected amounts of allergen- specific IgE (sIgE) have repeatedly been found. .ese discrepancies hinder diagnostics and research into clinically significant cuto. points for life-threatening symptoms. Methods: To evaluate whether the reported di.erences have led to changes in diagnostic testing, we analyzed data from six years of round robin testing (RRT, also known as proficiency testing) at the Institute of Standardization and Quality Control in Medical Laboratories (INSTAND e. V.) for the important allergen sources bee venom, wasp venom, and birch pollen. .e results of the four main suppliers of in vitro diagnostic sIgE testing were compared in a pseudo-anonymized form using overlay images of box plot graphs for the semiquantitative data and allergen class results. Coe.cients of variation (CV) were obtained to study the development of interlaboratory comparability. Results: We found t hat t he l arge d i.erences b etween the manufacturer collectives remained constant between January 2010 and April 2015 without any real improvement. .e CVs were good for two of the four analyzed suppliers, one was marginal and one above the quality level of 20 %. Conclusion: .e numerous publications that have found discrepancies in the sIgE results of the di.erent suppliers did not change the status quo within the last six years. Unfortunately, this is unlikely to change until there is a characterized standard material with known values of sIgE.