when to do blood tests after a virus / colds tr... - Thyroid UK

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when to do blood tests after a virus / colds trigger hyper symptoms

Applethorpe profile image
9 Replies

I have my bloods kit and I’m debating when to do it.

I gather that a virus will cause your t4/t3 to rise ? I can see why you wouldn’t want to lower your dose of levo on the basis of an atypical blood test.

However, I’m looking for a diagnosis. Surely the most important thing is to tie blood results to symptoms?

I am currently suffering from a cold which isn’t really going away. This has , as usual, triggered hyper symptoms which are : - having far more energy; my bedtime getting later even faster; eating more ; and a heavy, early period.

I want to ignore the advice to wait a couple (few?) weeks after a virus before doing bloods. First, I feel like I could be waiting indefinitely as I will likely get more viruses ( perhaps related to ME/CFS ).

Second, I’d like to see a doctor while I physically have the energy to do so. Third, surely this would be the best time to get a positive antibody test ? Also, if my results say I have high t4 /t3 , then that would confirm that my symptoms are due to this rather than cortisol which was mentioned previously. The tests also include cortisol.

Please let me know if I have completely misunderstood all this !

Thankyou.

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Applethorpe
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greygoose profile image
greygoose

Usually, a virus will cause your FT3 to drop, rather than rise, because of the effect it has on conversion.

Or, do you already know you have Hashi's and think that a virus will trigger a Hashi's 'hyper' swing? I think we need a little more information before being able to advise. :)

Applethorpe profile image
Applethorpe in reply togreygoose

OK, I have been reading other threads and have obviously got it wrong - so can I simply ask first, ‘ Why do you need to wait after a cold before doing blood tests ? ‘

Viruses definitely give me a ‘ hyper swing ‘. Slow dragon has helpfully linked below to my previous post giving the background. Basically I was diagnosed with de Quervain’s Thyroiditis eight years ago but my test results returned to normal, while my symptoms continued. So docs reckon there is nothing wrong with my thyroid. So I am really looking to explain both these hyper symptom swings I get and also the more lethargic symptoms I get afterwards. I’m on a symptoms rollercoaster without diagnosis or treatment.

Thankyou.

greygoose profile image
greygoose in reply toApplethorpe

Ah, de Quervain's. That seems to be the fashionable 'diagnosis' at the moment. And yesterday I read something rather interesting, which might interest you:

ncbi.nlm.nih.gov/pmc/articl...

Did you ever have your antibodies tested?

Why do you have to wait to do blood tests? Because if you've just had a virus, which would probably lower conversion and therefore FT3, and therefore cause TSH to rise, you need to wait until things go back to 'normal'. Or, as normal as possible. Until conversion has gone back to its former level, so that the FT3 rises to its former level and the TSH comes down. That is, of course, if you want results as accurate as you can get them. But, I realise that if you're trying to get a diagnosis, you might not want things to be 'normal', you'd want your TSH high and your FT3 low. But, there's no way you could get your FT4 low, so the results would be out of sync. Not that a doctor would realise that, but still...

Applethorpe profile image
Applethorpe in reply togreygoose

Do we know why conversion is poor during a cold ? ( or with low carbs ? )

I had a negative TSH receptor antibody test at the start, but I’ve never had TPO or Tg antibodies checked.

I’ve only had TSH tests from my GP , which I have had during previous ‘hyper flares’. They are always normal. So I really have no idea what is actually happening with my t4 and t3 with these symptoms.

I would assume that my t3 is currently high and causing my hyper symptoms. If a blood test confirms this, then I can only infer that the amount of t4 entering my bloodstream is enough to outweigh poor conversion.

The paper suggests you can have both de Quervain’s and Hashimoto’s at the same time ! radd Hashiboy So, not a cut and dried distinction.

greygoose profile image
greygoose in reply toApplethorpe

Do we know why conversion is poor during a cold ? ( or with low carbs ? )

To conserve energy, which is needed for healing with a virus. With low carbs it's because you need carbs to convert T4 to T3.

You really do need full thyroid testing to know what's going on:

TSH

FT4

FT3

TPO antibodies

Tg antibodies

vit D

vit B12

folate

ferritin.

Beware of symptoms! It's often difficult to distinguish between hypo and hyper symptoms, because so many of them are the same.

Hashiboy profile image
Hashiboy in reply toApplethorpe

Hi there, yes I'm realising I had one then the other ☹️

Applethorpe profile image
Applethorpe in reply toHashiboy

I was reading your thread about negative antibodies and I found it very interesting - with all the learned contributions from forum regulars. I’m sure I will return and reread. It all gets quite complicated !

I was given no treatment for de Quervain’s on the basis it was self limiting. I don’t know why they don’t give steroids at the start, which my second endo referred to in passing. I’m not sure what I have now as I have up and down symptoms and normal blood tests. I’ll continue to try to get to the bottom of things and will continue to post on here. :)

Hashiboy profile image
Hashiboy in reply toApplethorpe

Hi Applethorpe sorry you are still having a tough time. With de Quervain there is often a period of normal tests after the initial hyper phase. This can then change to a hypothyroid phase that's either temporary or permanent. So it's really important they keep testing for a year after the first normal test. I went from normal to severe Hypothyroidb in a period of about a month. My hyper phase lasted about three months and the normal phase only two months. Because everything is changing and you don't have a stable pattern of thyroid hormone you can get ill in the so called normal phase. I felt awful all stages. Good luck

SlowDragon profile image
SlowDragonAdministrator

Previous post a month ago

healthunlocked.com/thyroidu...

Perhaps test vitamin D now while you wait for cold to go

NHS easy postal kit vitamin D test £31 via

vitamindtest.org.uk

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