madman
Super Moderator
Biotin interference
Underrecognized patient safety risk in laboratory testing
In Western populations, dietary biotin intake is estimated to be 35 to 70 µg daily, a level in line with the recommended dietary allowance. Most multivitamin pills contain about 30 µg of biotin. High-dose supplementation (doses greater than 1 mg/d) plays a role in therapy for several diseases, including biotinidase deficiency, mitochondrial metabolic disorders, and multiple sclerosis. Doses up to 10 mg a day are frequently encountered in nutritional supplements taken to improve hair, skin, and nail health. The problem is that many common blood tests employ a biotin-streptavidin reaction as part of the test procedure. While the amount of usual dietary biotin intake is not expected to be high enough to affect these tests, biotin supplementation at doses greater than 1 mg per day can cause either falsely low or falsely high test results, depending on the analyte and platform used for testing.
A literature search revealed an increasing number of published cases, most describing the problem of biotin interference in thyroid function tests. High-dose biotin can produce a dangerous combination of positive and negative interference among the thyroid tests (free thyroxine, free triiodothyronine, thyroid-stimulating hormone, and thyroid-stimulating hormone receptor antibodies) and paint a picture of Graves disease in patients who have either no clinical symptoms or unrelated symptoms. Without good clinical observations, this could lead to unnecessary procedures and treatments. Interference of high-dose biotin with thyroid tests is particularly troubling for patients with multiple sclerosis, as large doses of this vitamin are emerging as a new treatment. Interference with parathyroid hormone, follicle-stimulating hormone, luteinizing hormone, sex-hormone binding globulin, estradiol, progesterone, testosterone, cortisol, folate, vitamin B12, and ferritin testing has also been reported.
The interference of high-dose biotin on immunoassays in the clinical laboratory is an emerging issue. Many questions have not been addressed. What is the prevalence of high-dose biotin in a given patient population? What are the pharmacokinetics of high-dose biotin? How effective is the use of streptavidin-agarose beads to remove biotin interference? For many laboratories, the current solution is basic: It is recommended that patients abstain from taking biotin for at least 48 hours before specimen collection. The most effective approach, however, is an extensive communication campaign to educate physicians and patients
Underrecognized patient safety risk in laboratory testing
In Western populations, dietary biotin intake is estimated to be 35 to 70 µg daily, a level in line with the recommended dietary allowance. Most multivitamin pills contain about 30 µg of biotin. High-dose supplementation (doses greater than 1 mg/d) plays a role in therapy for several diseases, including biotinidase deficiency, mitochondrial metabolic disorders, and multiple sclerosis. Doses up to 10 mg a day are frequently encountered in nutritional supplements taken to improve hair, skin, and nail health. The problem is that many common blood tests employ a biotin-streptavidin reaction as part of the test procedure. While the amount of usual dietary biotin intake is not expected to be high enough to affect these tests, biotin supplementation at doses greater than 1 mg per day can cause either falsely low or falsely high test results, depending on the analyte and platform used for testing.
A literature search revealed an increasing number of published cases, most describing the problem of biotin interference in thyroid function tests. High-dose biotin can produce a dangerous combination of positive and negative interference among the thyroid tests (free thyroxine, free triiodothyronine, thyroid-stimulating hormone, and thyroid-stimulating hormone receptor antibodies) and paint a picture of Graves disease in patients who have either no clinical symptoms or unrelated symptoms. Without good clinical observations, this could lead to unnecessary procedures and treatments. Interference of high-dose biotin with thyroid tests is particularly troubling for patients with multiple sclerosis, as large doses of this vitamin are emerging as a new treatment. Interference with parathyroid hormone, follicle-stimulating hormone, luteinizing hormone, sex-hormone binding globulin, estradiol, progesterone, testosterone, cortisol, folate, vitamin B12, and ferritin testing has also been reported.
The interference of high-dose biotin on immunoassays in the clinical laboratory is an emerging issue. Many questions have not been addressed. What is the prevalence of high-dose biotin in a given patient population? What are the pharmacokinetics of high-dose biotin? How effective is the use of streptavidin-agarose beads to remove biotin interference? For many laboratories, the current solution is basic: It is recommended that patients abstain from taking biotin for at least 48 hours before specimen collection. The most effective approach, however, is an extensive communication campaign to educate physicians and patients