Biotin query

[haggisplant]

Hello, I just wanted to clarify if biotin affects the t4 result (high) as well as the tsh result (too low)?

[Lalatoot]

because biotin is an ingredient used in many lab hormone test kits not stopping taking supplements with biotin a week prior to testing can interfere with the measurement of thyroid hormones

It does this in an inconsistent way, causing falsely elevated results from some labs, and falsely low results from others.

[haggisplant in reply to Lalatoot]

Thank you, I know this, is it the tsh as well as the t4 or just the tsh result that is affected?

[helvella Administrator Thyroid UK in reply to haggisplant]

You cannot know unless you find out exactly what analysis platform the lab uses. It could raise one test and lower another. And you are unlikely to get that information and also be able to use it to find out the possible effects. Even if you do find out, all you will know is that your test might have been affected but not by how much.

There are two approaches. Contact the lab and ask - making sure they know every test you have done. Or avoid biotin.

It was originally high dose biotin that certain groups of patients have used (e.g. multiple sclerosis patients). They saw some very odd results. As the reasons were investigated and the answers came out, it became clear that we should be careful if we take biotin. But ordinary, dietary levels of biotin are not seen to affect blood tests and some multivitamins and other possible supplements don't contain very much biotin.

If you want to know some more, one company has posted a fairly good description:

thermofisher.com/uk/en/home...

[haggisplant in reply to helvella]

Ok thanks. I’m still querying a couple of tests last year where the tsh was low snd the t4 high before I knew about biotin. Decisions to alter dosage were made based on those tests which I’ve been dealing with since. When I first found out i initially read it was the tsh that was affected but then since then it was unclear. And I’m querying many tests historically as I’ve always taken berocca which has it in and then pregnacare prenatal and pregnancy pills.

It’s quite possible that reading was correct in which case I’ve had some post partum issues or possibly something relating to some short courses of steroid I had for asthma.

I am now avoiding it prior to tests completely. Last test was 2.41 or similar but I’d been taking beta blockers occasionally, so I’ve stopped those to see if it helps. I’m just trying to work out my next visit to the Gp.

[SmallBlueThing in reply to haggisplant]

I was first aware of the biotin issue in autumn 2016, and used it to explain my TSH dropping from 0.43 to 0.11, with fT4 of 15 and 16. I ceased taking the all-in-one supplement and reduced my dose of levothyroxine as I realised I was having a flare, but was then faced with building back up and several months with TSH of 2 ~ 3, which precluded having NHS tests for my fT4.

[haggisplant in reply to SmallBlueThing]

Ok thanks, so it didn’t affect t4. But it seems to be variable and untrustworthy. I’ll have to just go forward from here.

[SmallBlueThing in reply to haggisplant]

I don't know what it did to my fT4, as it wasn't tested when my TSH rose above 1.0.

There was one test without biotin when I had reduced my levothyroxine. TSH had risen from 0.11 to 0.89 and fT4 had fallen from 16 to 12 (local range: 9 ~ 25pmol/L).

Several years ago, and before any treatment my TSH was 0.42 with fT4 of 14, and with the above-mentioned 0.89 TSH and 12 fT4 I wondered about central hypothyroidism (history of a couple of overnight hospital stays with concussion, which could have a bearing) alongside my autoimmune thyroiditis, but my GP said the tests aren't very reliable!

[Suzi_]

I should tell your dr u r taking Biotin

I would discontinue use of Biotin a few day’s before blood test, I understand it does effect your Thyroid blood test results.

[helvella Administrator Thyroid UK in reply to Suzi_]

The use of biotin, at least in higher doses, can affect a variety of blood tests. There is nothing special that means thyroid tests are affected more, or less, than other tests which use the same sort of technology.

[haggisplant in reply to helvella]

Is this something drs know about? Friends who are gps don’t seem to know and I tried to mention it to my Gp and was given a dismissive look. I know the BTF have covered it recently and they do try to get messages through to gps but it’s not always successful.

[helvella Administrator Thyroid UK in reply to haggisplant]

I'll pass on what has been published and, one might hope, distributed in the UK:

Taking biotin tablets can alter some lab test results

Many people take biotin tablets because they believe they will improve their hair, skin and nails. It has been known for some years that taking large doses of biotin can effect some lab test results. The EU recommended intake for biotin is approximately 0.05 mg (50 µg or mcg) a day, and vitamin supplements commonly contain this safe amount. However, much higher levels can be found in supplements widely promoted to benefit hair, skin and nails that contain up to 10 mg, 200 times the recommended intake, which can lead to interference in some laboratory tests.

The most striking interferences with lab test results have occurred in patients taking extremely large doses of up to 600 mg a day as part of trials for the treatment of progressive multiple sclerosis. The company sponsoring the biotin trials withdrew its application for licensing in December 2017 after the European Medicines Agency considered the available data for improvement and safety to be insufficient. The firm hopes a further large international trial will complete in 2019. Those involved are aware of biotin’s effect on lab tests.

A recent study looked at the effect of biotin and its metabolic break-down products. Dr Danni Li from the University of Minnesota and colleagues tested blood samples from six healthy adult volunteers before and after they had taken 10 mg of biotin daily for seven days. They reported the performance of 37 lab tests for 11 substances on four major diagnostic systems online in the Journal of the American Medical Association on 26 September 2017. All 37 tests used antibodies (immunoassays), 23 with a biotin-streptavidin reagent and 14 without to act as controls. None of the control results showed interference; of the 23 with biotin-streptavidin, five of the eight that used what is called a competitive immunoassay gave falsely high results while four of the 15 that used what is called a sandwich immunoassay gave falsely low results. The authors recommend that further studies should include patients with abnormal initial test results.

On 28 November 2017 the US Food & Drug Administration (FDA) published a Safety Communication addressed to people taking or considering taking biotin supplements, doctors requesting lab tests, lab personnel and lab test developers warning about their possible effects of biotin on lab test results. It should be stressed that biotin does not affect all laboratory test results, and all manufacturers of diagnostic equipment are likely to have communicated with testing laboratories, informing them of any interferences. Individual laboratories will have then taken steps to mitigate this interference.

If you are a patient, who does take large doses of biotin, then we suggest that you discuss this with your healthcare professional, who may need to seek advice from the local laboratory.

labtestsonline.org.uk/news/...

A statement from the ACB Scientific Committee regarding biotin / vitamin B7 interference in immunoassays issued July 2018

The use of over-the-counter (OTC) high dose biotin supplements has gained popularity in recent times. Biotin is also known as Vitamin B7. Many patients take biotin supplements (generally 5-10 mg tablets) marketed as beauty products to improve the health of hair, skin and nails. High-dose biotin (100 mg) is sometimes prescribed to treat metabolic diseases and there are also ongoing trials of mega-dose (up to 300mg/d) Biotin in Multiple Sclerosis. There is now an increasing awareness among laboratory professionals that taking large doses of biotin can interfere with some laboratory immunoassay test results. Interference may be positive or negative depending on assay design: sandwich-type immunoassays are generally negatively affected, and competitive designs are usually positively affected. Appropriate steps must be taken to reduce the potential for clinically misleading test results in order to avoid patient harm. This statement from the ACB Scientific Committee is primarily to raise awareness among clinical laboratory professionals and the following recommendations are set out to mitigate biotin interference:

1. Review your laboratory immunoassay repertoire to identify any assays using biotin technology. Communicate with the manufacturer to provide supplemental data on interference from biotin (up to at least 1200 ng/mL biotin) in their assays that use biotin technology, including the interference threshold for each assay (the lowest concentration of biotin in the sample that may cause clinically significant interference in the test result).

2. Perform a Risk Assessment for those tests identified as potentially susceptible to biotin interference. Many laboratory tests, including but not limited to cardiovascular diagnostic tests and endocrine tests, may potentially be affected. The Risk Assessment will help inform corrective/preventive action, including review of any alternative testing options / contingency plan.

3. In performing a risk assessment and designing a contingency plan, it may be useful to consider assays in three main categories:

○ High-volume endocrine / “screening” assays, often from GPs:

§ TSH, fT4, fT3, vit D etc

○ Urgent specialist assays, usually in hospital

§ e.g. hs-Troponin, NT-pro-BNP, PTH

○ Assays not identified as clinically significantly affected by any method

4. Some immunoassay designs are independent of the biotin/streptavidin couple, and could be considered as candidate assays for contingency testing. Laboratories are encouraged to incorporate a contingency pathway possibly involving a partnership with a nearby laboratory

5. Networks of laboratories may present an opportunity to moderate the risks. Harmonisation to a single manufacturer or platform renders laboratory networks susceptible to known and unknown risks related to interferences, supply problems or poor analytical performance. Networks of laboratories may wish to consider how to ensure a mixture of test platforms, manufacturers and techniques can be made available to help mitigate risk from biotin, as well as other as yet unknown issues

6. Educate laboratory staff and clinical users of the laboratory services about biotin interference for those tests in the laboratory identified as potentially susceptible.

7. Encourage clinicians to talk to their patients about any biotin supplements they may be taking, including supplements marketed for hair, skin, and nail growth. Clinicians must recognise that product labelling is sometimes obscure and patients may not even know they are on biotin.

8. If the laboratory/clinician have a test result that does not fit with the clinical picture, biotin ingestion as a potential cause of test interference will need to be excluded. Close communication between the laboratory, clinician and patient is vital in this context as it is difficult to positively identify samples that contain biotin.

9. Though manufacturer’s have not given any official guidance regarding the minimum intervals for blood sampling following last biotin dose, we suggest that assays with an interference threshold <30 ng/mL could be classified as more susceptible as this corresponds to the expected peak serum biotin concentration from OTC supplements of 5-10mg. Pharmacokinetic data in the literature does provide some useful guidance on washout periods required for assays with biotin interference.

10. Report to the manufacturer and the MHRA if you encounter an adverse event following potentially incorrect laboratory test results where biotin interference is suspected.

11. The ACB Scientific Committee suggests that laboratories should implement these recommendations to mitigate biotin interference by no later than February 2019.

acb.org.uk/docs/default-sou...

[haggisplant in reply to helvella]

Ok that’s great thanks.

[humanbean]

I don't think you can tell whether results will go up or down if they are affected by biotin. You might find this thread useful, and the links included in it are worth reading :

healthunlocked.com/thyroidu......

[HannahSv]

!!! Thyroid Month: Beware of Biotin

endocrinenews.endocrine.org...

[helvella Administrator Thyroid UK]

This is a very recently published article/letter. The full thing is not yet available but this extract gives a flavour.

My take is that they are trying to downplay any possible impact while telling everyone to be careful. Nonetheless, they talk about dose of 10 milligrams a day. "Not our fault, guv."

Doses into hundreds of milligrams have been tried by people with Multiple Sclerosis.

I particularly dislike their use of the phrase "due to unfounded claims" - they do not have the evidence that the claims are unfounded. Every single person who has tried biotin might have improved their hair, nails and skin. All they have is lack of evidence in the form they will accept. They have no proof the claims are unfounded. (To be honest, I do not know how effective it is, if at all, and quite possibly there might be proper published research of these levels of biotin.)

Dear Editor,

Immunoassays (IAs) based on streptavidin-biotin binding are widely used in clinical laboratory testing owing to the high affinity and stable interaction between streptavidin and biotin (vitamin B7) and the development of various biotinylation methods [1]. Biotin is a water-soluble B-complex vitamin and a coenzyme responsible for carboxyl transfer in essential carboxylases. Circulating serum concentrations of biotin in the general population typically range from 0.1 ng/mL to 0.8 ng/mL [2]. Biotin is rapidly absorbed, reaches peak plasma concentrations within 1–2 hours, and has an effective serum half-life of 15 hours [3]. Oral administration of biotin doses of 10 mg resulted in peak plasma concentrations ranging from 53 ng/mL to 141 ng/mL [3, 4]. Considering a maximum dosage of 10 mg once a day (q.d.; 10 mg is >300-fold the adequate daily intake) via over the counter (OTC) biotin products, the serum biotin concentration would drop below the in vitro interference threshold of ≤30 ng/mL after eight hours [3]. A high biotin concentration in the blood can interfere with IAs based on streptavidin-biotin binding and is known to cause false high results in competitive IAs and false low results in sandwich IAs [1]. Although the recommended daily intake of biotin is low (30 µg/day), the use of high-dose biotin supplements (up to 10 mg), which are available OTC, has increased in recent years due to unfounded claims that biotin exerts beneficial effects on hair, nails, and skin [5]. According to one survey, 7.7% (95% confidence interval [CI], 6.6–8.9%) of an outpatient population (N=1,944) indicated biotin use; measuring biotin in plasma samples from emergency department patients (N=1,442) showed that 7.4% (95% CI, 6.2–8.9%) had a concentration at or above the lowest known threshold (10 ng/mL) for biotin interference in a Roche Diagnostics IA (Indianapolis, IN, USA) [6].

synapse.koreamed.org/DOIx.p...

[helvella Administrator Thyroid UK]

No - you said 50 micrograms, didn't you?

Which is very close to what we might get from diet and seems utterly insignificant in terms of test interference.

[helvella Administrator Thyroid UK]

Sorry if that came across a bit bluntly.

I hope that there is another interpretation. It is beyond what I know anything about so I'd rather keep quiet than say anything that might be wrong.