Uptick in subclinical hyperthyroidism?

[FrustratedFamDoc]

Over the last 6 months, I have diagnosed more new onset subclincal hyperthyroidism cases than I have ever seen. It is at least 4 fold. at least. Repeat TSH confirms original findings. Normal T3/FT4. We use several labs around town, all with the same findings.

Is anyone else noticing this as well?

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[5150man]

Over the last 6 months, I have diagnosed more new onset subclincal hyperthyroidism cases than I have ever seen. It is at least 4 fold. at least. Repeat TSH confirms original findings. Normal T3/FT4. We use several labs around town, all with the same findings.

Is anyone else noticing this as well?

I haven’t noticed an uptick. But I also can’t think of anyone in 17 years of practice that felt any different on their 50 mcg levothyroxine to get their mildly elevated TSH back to normal.
Do you see treatment helping symptoms?

 

[FrustratedFamDoc]

I haven’t noticed an uptick. But I also can’t think of anyone in 17 years of practice that felt any different on their 50 mcg levothyroxine to get their mildly elevated TSH back to normal.
Do you see treatment helping symptoms?

Good to see another 15 year member

You read me wrong.

Hyperthyroidism.

TSH values in the .02 to .3 ish range. In older people, at risk for osteoporosis and Afib, so it's been kind of annoying. 3 and 6 month rechecks also coming back off.

In my 14 years of practice, I've yet to encounter anyone who felt better with a gentle whiff of synthroid either.

 

[5150man]

Good to see another 15 year member

You read me wrong.

Hyperthyroidism.

TSH values in the .02 to .3 ish range. In older people, at risk for osteoporosis and Afib, so it's been kind of annoying. 3 and 6 month rechecks also coming back off.

In my 14 years of practice, I've yet to encounter anyone who felt better with a gentle whiff of synthroid either.

My bad 😞.
I haven’t seen that one either but subclinical hyperthyroidism would probably be more amenable to treatment. 😀

 

[FrustratedFamDoc]

My bad 😞.
I haven’t seen that one either but subclinical hyperthyroidism would probably be more amenable to treatment. 😀

No worries. Having to stare at a computer screen all day will do that.

 

[sloh]

No worries. Having to stare at a computer screen all day will do that.

Or bc so many patients come in complaining that their subjective fatigue and obesity/overweight is due to hypothyroidism, we reflexively think of “hypothyroid” (even though it really isn’t)

 

[Keona]

Over the last 6 months, I have diagnosed more new onset subclincal hyperthyroidism cases than I have ever seen. It is at least 4 fold. at least. Repeat TSH confirms original findings. Normal T3/FT4. We use several labs around town, all with the same findings.

Is anyone else noticing this as well?

Yes! I thought it was just our lab but I’ve had 5 or 6 lately. A few of them are normal on the 6 month repeat testing some of them are feeling awful so I send those to endocrinology earlier.

 

[FrustratedFamDoc]

What's your location? I'm in Georgia.

 

[Keona]

What's your location? I'm in Georgia.

Ky had another one yesterday

 

[Splenda88]

Or bc so many patients come in complaining that their subjective fatigue and obesity/overweight is due to hypothyroidism, we reflexively think of “hypothyroid” (even though it really isn’t)

You better not tell them that they need to lose weight.

 

[rokshana]

Are they taking any biotin? Amy hair, skin, and nails products?

 

[Keona]

Are they taking any biotin? Amy hair, skin, and nails products?

Not sure. I’ll ask the next one that comes back in. My one I’ve sent to endocrinology recently hasn’t come back for her follow up with me yet. Does biotin affect tsh?

 

[VA Hopeful Dr]

I believe it affects thyroid assays, not the hormone levels themselves.

 

[wholeheartedly]

Hello, former clinical lab scientist here. A couple thoughts.

there are several major manufacturers of laboratory analyzers that run thyroid tests. Even if you are getting results that seem off from more than one lab, that doesn’t mean it can’t be an assay issue as they could be using the same analyzer/reagent kit. There are checks and balances on both the manufacturer side and lab side to prevent issues, but it’s still not unheard of to get a lot that performs oddly. Without feedback from the clinicians it can be hard sometimes for labs to detect and pinpoint.

Might help to ask around what manufacturer and assay is being used for the thryoid tests at each of the labs where you’re seeing this. If you can reach out to a lab director (PhD or MD level) with specific pts and examples of results that don’t seem right, they might be able to look into it more closely. At least at academic places if you can provide good details and just come at it seeking help (not accusing the lab of screwing something up) the PhD lab director types especially seem to really like trying to figure these things out.

Second, definitely ask about biotin. It interferes with immunoassay tests which includes most thyroid tests. The direction of the interference depends on the assay design. The trick is, biotin can be called a lot of different things and so patients might not even realize they’re taking it, or something that contains a lot of it. So you have to ask about all kinds of supplements and stuff for hair and nails or concentration boosting (it’s being marketed as a cure all for soooo many things). You might just want to have them bring in anything OTC supplement they’re taking and check the label. A former, colleague of mine did a lot of work on biotin interference. It’s kind of wild how much ppl wind up taking these days and how much it screws up testing.

Other supplements can do wonky stuff too so if there’s something new out there circulating around or some new internet fad, could cause issues but probably would be more difficult to pin down.

 

[VA Hopeful Dr]

Hello, former clinical lab scientist here. A couple thoughts.

there are several major manufacturers of laboratory analyzers that run thyroid tests. Even if you are getting results that seem off from more than one lab, that doesn’t mean it can’t be an assay issue as they could be using the same analyzer/reagent kit. There are checks and balances on both the manufacturer side and lab side to prevent issues, but it’s still not unheard of to get a lot that performs oddly. Without feedback from the clinicians it can be hard sometimes for labs to detect and pinpoint.

Might help to ask around what manufacturer and assay is being used for the thryoid tests at each of the labs where you’re seeing this. If you can reach out to a lab director (PhD or MD level) with specific pts and examples of results that don’t seem right, they might be able to look into it more closely. At least at academic places if you can provide good details and just come at it seeking help (not accusing the lab of screwing something up) the PhD lab director types especially seem to really like trying to figure these things out.

Second, definitely ask about biotin. It interferes with immunoassay tests which includes most thyroid tests. The direction of the interference depends on the assay design. The trick is, biotin can be called a lot of different things and so patients might not even realize they’re taking it, or something that contains a lot of it. So you have to ask about all kinds of supplements and stuff for hair and nails or concentration boosting (it’s being marketed as a cure all for soooo many things). You might just want to have them bring in anything OTC supplement they’re taking and check the label. A former, colleague of mine did a lot of work on biotin interference. It’s kind of wild how much ppl wind up taking these days and how much it screws up testing.

Other supplements can do wonky stuff too so if there’s something new out there circulating around or some new internet fad, could cause issues but probably would be more difficult to pin down.

But seriously, great post!

 

[rokshana]

Not sure. I’ll ask the next one that comes back in. My one I’ve sent to endocrinology recently hasn’t come back for her follow up with me yet. Does biotin affect tsh?

FDA put out an alert back in 2017 that biotin interferes with many tests including TSH and FT4…some machines are affected so import to know what machines the labs are run on.

They just need to be off the biotin for a few days before getting any TFTs.

Typically these pts are asymptomatic amd yet labs look hyperthyroid.

And …troponins assays are effected by biotin…

Assessment of biotin interference in thyroid function tests

Supplemental Digital Content is available in the textThe aim of the study was to systematically characterize the interference of biotin on thyroid function tests and biotin washout periods.Ten healthy adults were recruited with administration of 5 and ...

www.ncbi.nlm.nih.gov

FDA reminds public of possible biotin interference for certain tests

FDA updated its safety communication to remind public that biotin, often found in dietary supplements, can significantly interfere with certain lab tests.

www.fda.gov

 

[Keona]

FDA put out an alert back in 2017 that biotin interferes with many tests including TSH and FT4…some machines are affected so import to know what machines the labs are run on.

They just need to be off the biotin for a few days before getting any TFTs.

Typically these pts are asymptomatic amd yet look hyperthyroid.

And …troponins assays are effected by biotin…

Assessment of biotin interference in thyroid function tests

Supplemental Digital Content is available in the textThe aim of the study was to systematically characterize the interference of biotin on thyroid function tests and biotin washout periods.Ten healthy adults were recruited with administration of 5 and ...

www.ncbi.nlm.nih.gov

FDA reminds public of possible biotin interference for certain tests

FDA updated its safety communication to remind public that biotin, often found in dietary supplements, can significantly interfere with certain lab tests.

www.fda.gov

Thanks! I’ll start asking and checking on that!!

 

[FrustratedFamDoc]

VERY much appreciated info.

My town has had factory pollution over the years. GE had a medium transformer plant that has been closed for decades, but is now no man's land due to the massive PCB contamination. The property is gigantic and just sits there. People used to take the stuff home and put it in the yard to keep termites away before anyone knew better. They paid untold millions to dredge it out of the Hudson, but that's another story. Agent orange was made not far from here as well.