Susceptibility of Cardiac Troponin Assays to Biotin Interference

Abstract

Objectives To investigate biotin interference on three cardiac troponin (cTn) assays and demonstrate a method to overcome biotin interference. Methods cTn levels were measured in (1) plasma from healthy volunteers on 10-mg daily biotin supplementation mixed with a plasma with known elevated troponin, (2) plasmas with known elevated cTn after mixing in reagent biotin to simulate supplementation, and (3) biotin-spiked plasma specimens pretreated with streptavidin-agarose beads. Results Daily biotin ingestion (10 mg) and studies simulating daily biotin use resulted in significant interference in the Gen5 cardiac troponin T (cTnT) assay; the contemporary Gen 4 cTnT and high-sensitivity cardiac troponin I (hs-cTnI) assays were unaffected. The biotin interference threshold was 31, 315, and more than 2,000 ng/mL for Gen5 cTnT, cTnT, and hs-cTnI assays, respectively. Streptavidin pretreatment blocked biotin interference in cTn assays. Conclusions Biotin interference is possible at plasma concentrations achievable by ingestion of over-the-counter supplements that may lead to delayed or missed diagnosis of myocardial injury with the Gen5 cTnT assay.

Laboratory-related issues in the measurement of cardiac troponins with highly sensitive assays

“…However, biotin interference thresholds between different hs-cTn assays can vary substantially, from 2.5 to 10,000 ng/mL [68,80]. Frame et al have experimentally shown a negative interference on hs-cTn T assay at biotin concentrations >30 ng/mL (approximately 10× lower than the fourthgeneration cTn T assay), while the Abbott hs-cTn I assay was not affected by biotin concentrations in blood up to 2000 ng/mL, due to a different assay design [81]. Although these findings require caution in considering the impact of biotin intake on some hs-cTn assays, they did not elucidate the real clinical impact of this issue.…”

A Dilution Method to Mitigate Biotin Interference in Cardiac Troponin T Testing

“…Biotin interference has been shown to cause false-negative results for fifth-generation cTnT assays because the assay uses biotin-streptavidin binding (12). In our hands, we see interference of cTnT at biotin concentrations >50 ng/mL that may be clinically significant.…”

Biotin interference in cardiac troponin immunoassay – where the wild things are?

“…In a volunteer study, five normal individuals ingested a supplement containing 10 mg biotin per day, a commonly available dose. The post ingestion levels of biotin detected would have been expected to generate a significant fall in measured troponin values [19]. This study also showed the variability in dose response between individuals following biotin ingestion.…”