The issue with biotin interfering with blood tests has been much discussed. Now a paper which suggests that interference by anti-streptavidin antibodies is more common than thought.
Unfortunately, whereas with biotin we can do something (stop taking biotin for a few days before a test), with these antibodies, we can do nothing.
Interference of anti-streptavidin antibodies in immunoassays: a very rare phenomenon or a more common finding?
Nick Verougstraete / Mario Berth / Mario Vaneechoutte / Joris Delanghe / Nico Callewaert
Published Online: 2019-11-29 | DOI: doi.org/10.1515/cclm-2019-1064
Abstract
Background
Anti-streptavidin antibodies (ASA) may cause analytical interference on certain immunoassay platforms. Streptavidin is purified from the non-pathogenic Streptomyces avidinii soil bacterium. In contrast to interference with biotin, ASA interference is supposed to be much rarer. In-depth studies on this topic are lacking. Therefore, we carried out an analysis toward the prevalence and the possible underlying cause of this interference.
Methods
Anti-streptavidin (AS)-immunoglobulin G (IgG) and AS-IgM concentrations were determined on multiple samples from two patients with ASA interference and on 500 random samples. On a subset of 100 samples, thyroid-stimulating hormone (TSH) was measured on a Cobas analyzer before and after performing a neutralization protocol which removes ASA. The relationship between the ratio of TSH after neutralization/TSH before neutralization and the ASA concentration was evaluated. Subsequently, an extract of S. avidinii colonies was analyzed using sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and immunoblotting.
Results
A positive correlation between AS-IgM concentrations and TSH ratio was obtained. Eight samples out of 500 exceeded the calculated AS-IgM cut-off value. In comparison to the AS-IgM concentrations in the population, titers from the two described cases clearly stood out. The isolated cases represent the end of a broader spectrum as there is a continuum of AS-IgM reactivity in the general population. We could not observe any differences in the immunoblot patterns between the cases and controls, which may indicate the general presence of ASA in the population.
Conclusions
Interference due to ASA is more prevalent than initially thought and is caused by IgM antibodies.
This article offers supplementary material which is provided at the end of the article.
Keywords: anti-streptavidin antibodies; biotin; interference; thyroid-stimulating hormone (TSH)
degruyter.com/view/j/cclm.a...
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