Many tests offered throughout the province are based on immunoassays that are impacted by the presence of large amounts of biotin. This is because these assays utilize the interaction of biotin with streptavidin as part of their measurement. Biotin interference may lead to falsely low, falsely high, or invalid results, depending on the immunoassay design. Some examples of impacted assays include (but are not limited to) the high sensitivity Troponin T and βhCG assays as well as urine pregnancy screening tests used across the province (within the lab as well as point of care settings).
It has been shown that biotin doses greater than 1 mg (1000 μg) per day can produce sufficient levels of biotin in the blood to cause the above described interferences. We therefore recommend that patients abstain from taking biotin for 48 hours before specimen collection. For more information about biotin and its effect on a specific test, please contact your local laboratory.