IMPORTANCE: Biotinylated antibodies and analogues, with their strong binding to streptavidin, are used in many clinical laboratory tests. Excess biotin in blood due to supplemental biotin ingestion may affect biotin-streptavidin binding, leading to potential clinical misinterpretation. However, the degree of interference remains undefined in healthy adults. OBJECTIVE: To assess performance of specific biotinylated immunoassays after 7 days of ingesting 10 mg/d of biotin, a dose common in over-the-counter supplements for healthy adults. DESIGN, SETTING, AND PARTICIPANTS: Nonrandomized crossover trial involving 6 healthy adults who were treated at an academic medical center research laboratory EXPOSURE: Administration of 10 mg/d of biotin supplementation for 7 days. MAIN OUTCOMES AND MEASURES: Analyte concentrations were compared with baseline (day 0) measures on the seventh day of biotin treatment and 7 days after treatment had stopped (day 14). The 11 analytes included 9 hormones (ie, thyroid-stimulating hormone, total thyroxine, total triiodothyronine, free thyroxine, free triiodothyronine, parathyroid hormone, prolactin, N-terminal pro-brain natriuretic peptide, 25-hydroxyvitamin D) and 2 nonhormones (prostate-specific antigen and ferritin). A total of 37 immunoassays for the 11 analytes were evaluated on 4 diagnostic systems, including 23 assays that incorporated biotin and streptavidin components and 14 assays that did not include biotin and streptavidin components and served as negative controls. RESULTS: Among the 2 women and 4 men (mean age, 38 years [range, 31-45 years]) who took 10 mg/d of biotin for 7 days, biotin ingestion–associated interference was found in 9 of the 23 (39%) biotinylated assays compared with none of the 14 nonbiotinylated assays (P = .007). Results from 5 of 8 biotinylated (63%) competitive immunoassays tested falsely high and results from 4 out of 15 (27%) biotinylated sandwich immunoassays tested falsely low. CONCLUSIONS AND RELEVANCE: In this preliminary study of 6 healthy adult participants and 11 hormone and nonhormone analytes measured by 37 immunoassays, ingesting 10 mg/d of biotin for 1 week was associated with potentially clinically important assay interference in some but not all biotinylated assays studied. These findings should be considered for patients taking biotin supplements before ordering blood tests or when interpreting results. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT03034707.
|Original language||English (US)|
|Number of pages||11|
|Journal||JAMA - Journal of the American Medical Association|
|State||Published - Sep 26 2017|
Bibliographical noteFunding Information:
completed and submitted the ICMJE Form for Disclosure of Potential Conflicts of Interest. Dr Karger reports receiving grants and nonfinancial support from Siemens Healthcare Diagnostics. Dr Sokoll reports receiving grant support from Abbott Laboratories. Dr Killeen reports receiving personal fees from Roche Diagnostics and Abbott Diagnostics. No other disclosures or possible conflicts of interest were reported.
publication was supported by grant UL1TR000114 from the National Center for Advancing Translational Sciences of the National Institutes of Health. Funds to support blood collections and biotin measurements were provided by the University of Minnesota Undergraduate Research Opportunities Program and the University of Minnesota Medical Center, respectively. Funds to support hormone and nonhormone assay measurements were provided by participating laboratories.