Biotin interference with clinical laboratory tests

Biotin can significantly interfere with certain clinical laboratory tests, resulting in incorrect laboratory values. Potential biotin interference has been identified with oral products containing ≥ 150 mcg biotin per dose unit and parenteral products containing ≥60mcg biotin per dose unit. If undetected, the incorrect test results might lead to misdiagnosis or inappropriate patient management.

Biotin, also known as vitamin B7, is a water-soluble vitamin that acts as an enzyme cofactor in various metabolic processes. There are three parenteral products containing biotin registered locally, namely Cernevit® (Baxter Healthcare Asia Pte Ltd), SoluvitTM N (Fresenius Kabi Singapore Pte Ltd), and Tamipool® (Medipharm Pte Ltd). All three products are multivitamin infusions containing ≥60mcg biotin per dose unit. They are indicated as a supplement in intravenous nutrition to meet the daily requirements of vitamins, when oral administration is either contraindicated, impossible or insufficient (e.g. due to malnutrition or gastrointestinal malabsorption). Biotin can also be found in health supplements for oral use, such as multivitamins, prenatal vitamins, and products promoting hair, skin and nail growth.

Biotin interference with clinical laboratory tests

Some laboratory tests are based on a streptavidin-biotin interaction to determine a variety of biomarkers, including hormones, cardiac markers, tumour markers, and infection markers, as well as to determine the concentration of drugs. Biotin is not expected to interfere with laboratory tests when taken at levels found naturally in food or at amounts near the recommended daily intake of 30 mcg.1 However, in patients taking biotin-containing products at higher doses, competition with biotinylated reagents may result in clinically significant false results (i.e. incorrectly increased or decreased) in these tests. This poses a potential risk for delayed diagnosis, wrong diagnoses and unnecessary treatments. For instance, biotin interference could lead to falsely depressed thyroid stimulating hormone (TSH), and falsely elevated free triiodothyronine (T3) and free thyroxine (T4), which could result in a misdiagnosis of Graves’ disease.

The risk of obtaining incorrect test results due to biotin is higher in patients receiving high-dose biotin therapy for certain conditions (e.g. multiple sclerosis or rare metabolic disorders), renal failure patients, neonates, children and pregnant women. The popularity of dietary supplements marketed for improving hair, skin and nail health has also been reported to contribute towards the increasing use of high-dose biotin.  

International regulatory actions

In January 2019, the European Medicines Agency’s (EMA) Pharmacovigilance Risk Assessment Committee (PRAC) concluded that there was sufficient evidence to support a potential interference with clinical laboratory tests of oral medicinal products containing ≥ 150 mcg biotin per dose unit, and parenteral medicinal products containing ≥ 60 mcg biotin per dose unit.2 The EMA PRAC requested for the product information of these products to be updated to reflect this risk.

Apart from the EMA PRAC, the US Food and Drug Administration (US FDA) had issued a safety communication in November 2017 to alert the public, healthcare professionals, laboratory personnel and laboratory test developers on the potential interference of laboratory tests with the use of biotin.3 The FDA had highlighted an increase in the number of reported adverse events related to this risk, including one death arising from falsely low troponin test results. The agency informed that it would work with stakeholders to better understand the issue, and to develop additional future recommendations for safe testing in patients who had taken high levels of biotin when using laboratory tests that use biotin technology.

Local situation and HSA’s advisory

To date, HSA has not received any local adverse event report of biotin interference resulting in incorrect laboratory results. The local package inserts of parenteral biotin-containing products are being updated to include warnings on this interference, and a company-initiated Dear Healthcare Professional Letter was also issued for Soluvit™ N in May 2019 to highlight this risk.

Healthcare professionals are advised to consider the possibility of biotin interference when ordering laboratory tests for their patients and when interpreting laboratory results (especially if the results do not match the clinical presentation and/or other investigations). This may involve asking their patients about the use of biotin health supplements, including those marketed for hair, skin and nail growth, as biotin in the patients’ specimens could result in the generation of incorrect test results. As a general precaution, some local hospital laboratories have advised patients to stop biotin therapy for at least 12 hours before blood sample collection is done to minimise falsely increased/decreased laboratory results arising from biotin interference.4,5

References

  1. Can Fam Physician 2018; 64:370
  2. https://www.ema.europa.eu/en/documents/prac-recommendation/prac-recommendations-signals-adopted-14-17-january-2019-prac-meeting_en.pdf
  3. https://www.fda.gov/medical-devices/safety-communications/fda-warns-biotin-may-interfere-lab-tests-fda-safety-communication
  4. https://www.sgh.com.sg/patient-care/specialties-services/clinical-biochemistry
  5. https://nuhsingapore.testcatalog.org/show/T3
Healthcare professional, Industry member, Therapeutic Products
Published:

Safety Alerts