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Help Interpreting Thyroid Bloods(61 Posts)
I've been having problems with constipation and tiredness for some time. My B12 and Vitamin D were low but in the normal range, so I've been taking supplements. The doctor checked my TSH and it was 2.1.
I decided to have a private blood test of my thyroid and the results are as follows:
Free T4 11 (range 12-22)
Free T3 3.8 (range 3.1-6.8)
Does anyone know what this means? I seem to have low Free T4 and although the Free T3 is within range, it is at the lower end. Is this indicating a problem with the pituitary gland (tumor?!)
This is a difficult one.
It doesn't really mean a huge amount though I agree the results are not optimal.
In an ideal world you would get antibodies checked however that's unlikely via GP unless tsh was nearer 4.
How long have you been taking supplements etc? And what are those scores now? Ie are they now good? It might be worth waiting for a while after those are good (3-6 months) and retesting thyroid.
Alternatively you could discuss symptoms with the slightly low thyroid results and request monitoring or possibly an endo referral.
It is a very rare possibility that it could be pituitary but I'm not sure what those results would look like and imagine other things need to be ruled out first eg antibodies.
How long have you had symptoms and have you had a baby?
Your tsh has improved between results. It's possible your body has reacted to a period of stress or ill health. Not unreasonable to ask to be monitored with these symptoms.
I don't understand the way antibody tests are requested these days, possibly if your tsh was around 4-9 as this would be subclinical hypothyroidism
Are you in any medication or hormone pills?
thank you for responding!
I had a baby 7.5 months ago.
I'm on sertraline. No other medication other than the b12 and vitamin D I've self supplemented. I was taking iron supplements on prescription as my ferritin was 13 and low. I had to stop as it was making my constipation so much worse. Even laxatives weren't helping so I don't know if I was on it long enough for ferritin to rise sufficiently. I was on it for around 6 weeks.
I am waiting on an antibody test as I paid privately. Only one type of antibody though. I can't remember what it was called but I was told it was the one for underactive thyroid.
Could this be caused by antibodies then? I'm worried as I have health anxiety and everything I googled said that if the TSH is normal the pituitary might be to blame and it could be a tumor!
Only other relevant info is my mother has an underactive thyroid which is what prompted me to get checked when I was having thee symptoms. She had a brain MRI recently for something not related and they noted her thyroid was very small, almost non-existent. She hasn't had antibody or t3/t4 bloods done ever. Just TSH.
You’ve obviously done your homework. Low/”normal” TSH with low FT4 and FT3 can be indicative of a pituitary problem, but probably not a tumour! With thyroid hormones that low, the pituitary would normally kick out more Thyroid Stimulating Hormone to get the thyroid to produce more T4. In your case that is not happening.
If I were you I would read up on secondary hypothyroidism, check the NICE guidelines and go back to your GP and ask for a referral to an endocrinologist. Although your TSH looks good, you simply don’t have enough thyroid hormone circulating to enable you to feel well.
In the meantime, get your B12 and vitamin D up and if you can get your folate tested and your ferritin up to optimal level, that will help as well. There are plenty of iron supplements around that aren't as bad to take as standard NHS ones. Check out Cytoplan. Someone on here recommended them to me and they saved my bacon when it came to iron levels.
If your mother has an underactive thyroid then there may well be a hereditary element. It’s all part of the picture.
When were both tests (or how soon after baby and how soon after sertaline)?
To me (and probably GP if he saw results) it looks like tsh is resolving and moving in the right direction. At the same time you were right to look into it imo due to family history.
(Healthy) Thyroids naturally grow and change during pregnancy. Postnatal you can be a time when hypothyroidism kicks in. As you are post baby, there could possibly be something going on, at the same time thyroid could be adjusting. I'm not a doctor and I don't know what is expected post baby.
It's worth being aware of it runs in your family. This could mean eventually something could go wrong, but also possibly not yet. So, it's not unreasonable to ask for another test in the future esp if symptoms get worse. (I would sort of bet you might eventually. However my sister isn't hypo, I am and my mum is.)
The problem is its a very slow process and clinically your tsh is improving (t4 and t3 are a bit low but these vary and are not as static as tsh) - this improvement is good.
Now - sertaline is a tricky one. If you were taking thyroxine, you might need a little more. Bizarrely it does affect it some how but the info I have is regarding if you have hypothyroidism and are on thyroxine. (BMA thyroid book, can get from Amazon, it's a very good reference guide and BMA approved.
However I have no idea what that means in regards to normal thyroid function and sertraline. It's completely possible it's slightly impacted but thyroid is readjusting - this is total speculation on my part.
Tsh is released to stimulate the thyroid to make more t4 and t3 but this can be a very slow process hence why tests can be 3-6 months of being monitored.
I know this is probably frustrating, but as I say it's not unreasonable to keep an eye on it in the future due to family history.
If tsh gets to around the 4 mark GP will consider treatment, and certainly antibodies.
I would definitely get your ferritin much, much higher - eg over 70. Take with vit c or orange juice. And check your b12 and vit d are optimal too.
(Regarding antibodies - I know I had a different one to the usual one so I don't understand that process now) .
I'm sorry I missed the health anxiety bit. I think you do need to try to recognise that these results are ok but it's not unreasonable to consider it as a possibility- but not let it take you over.
And I don't think the answer is to come off sertaline - certainly without discussion with GP. I was on sertaline and it was a lovely medication, and bf friendly.
Yes thyroids shrivel up. They wouldn't do antibody test if her tsh was high; they'd assume she did have them. It can clarify the 'grey areas'.
I don't fully understand health anxiety however I do know what it feels like to feel dismissed regarding health and struggling on.
Personally I find understanding things helps. You could refer to the nice guidelines and certainly refer to the book I mentioned which I will link to.
My GP did say that thyroid issues were not always well managed by gps as its such a grey area.
I've looked at my copy again and I feel a lot will help to explain things.
Also - different labs use different reference ranges. Your two scores may not correlate.
Sorry more questions! Have you showed your GP the full blood results?
Looking through that book - it's so tricky as ranges vary - but it could be worth asking GP to monitor you, and try to get labs to do your t4 and t3.
The book also mentions post partum thyroiditis which does not need treatment as it will recover.
Basically it's not a black and white thing.
It takes time and working with your GP. And it's not unreasonable to return in a few months or have a further discussion or see a different GP.
Thanks both of you.
I haven't shown the GP the results as I was waiting on a final blood test (antibodies) but it turns out it's gone missing so it looks like I'm going to need to give blood again for that one. I'm planning to make an appointment with the GP though.... although I'm sure they wont be too impressed with me, as they had previously tested my TSH and told me my thyroid was fine and to go away.
I've had an interpretation of the results from a doctor at the company who took the blood -
"The thyroxine level is on the low side, although the Thyroid Stimulating Hormone (TSH) level is currently within normal limits. If you are already taking thyroxine medication, dose adjustment may be indicated – in which case it would be sensible to have a discussion with your usual doctor. If you are not taking thyroxine medication, it would be wise to keep an eye on this level – either by reference to previous results if known, or by checking thyroid function again in 6 months time or so. There is a possibility that hypothyroidism (underactive thyroid gland) will develop if the thyroxine level fails to rise (a low level implies reduced thyroxine production from the thyroid gland). You may wish to consider testing for thyroid antibodies (if you have not already done so) as your lifetime risk of developing thyroid disease would be greater if these antibodies were present. If you have, or develop, any symptoms suggestive of thyroid illness I advise you to make contact with your usual doctor."
It seems a bit vague to me. If the FT4 is low doesn't that mean I already am hypo, even if it's secondary? The doctor seems to be saying I'm not hypo?
I've been feeling awful for ages Clarella, although it's really got bad since having the baby. I suppose it could be post-partum related, although I'd hope after 8 months my body might be settling down a bit?
Thanks MrsT I will see if I can find anything in the NICE guidelines.
If I asked for an endo referral off the back of these results would they usually medicate or would they not be likely to do that if the TSH is normal? Surely the T4 being low needs correcting? I'm wondering if I need to be picky over which endo I ask to be referred to or if its standard to treat this on the NHS.... any ideas?
Also, if it was post partum thyroiditis wouldn't my TSH be elevated? I just find it weird that the TSH is almost optimal with such low FT4.
Indeed, if it was a transient thyroiditis, I sound expect to see raised TSH.
Your FT4 is below range and your FT3 is very, very low, both of which, with a good looking TSH are classic for secondary hypothyroidism.
Ask your GP for an urgent referral to an endocrinologist.
Thanks MrsTweedie. I've booked an appointment for next week!
Font urgent yo outing the relevant parts of the NICE Guidelines with you. That is your GP's standing instructions so difficult for him to disagree.
Let us know how you get on.
Thank you for starting this thread Star, do you mind if I ask which company you used to do the Thyroid tests ad how much they charged? How much was the antibody test?
Sorry star tried to reply a couple of times to this thread today!
Good luck with GP and do what Mrs T says!
Very annoying about the antibody test. It might be worth asking GP to do it? (Point to nice guidelines part on this).
did you have a post partum haemorrhage?
HaryLittleCarrot - that that I am aware of. I was told I had minimal bleeding. Less than average. Although I did go for a shower an hour after giving birth and a lot of blood did come out of me and I fainted. I don't like blood though, and the shower was literally a 'blood bath'. I assume I would know about it if I had a haemorrhage though?
Just thought I'd update you as I've just been to the GP...
She said that although my FT4 is below range, it's only just below range and didn't seem too concerned. She said some people have very low FT4s when they are hypothyroid so mine isn't that bad.
Has anyone come across any documentation which plots levels against how people feel? How low does the FT4 get usually in people with hypothyroidism? Is my FT4 actually quite high for someone hypo?
She says she wants me to re-do the test as a first step as she said it was unusual to have low FT4 with my TSH being so normal. She's also testing for a few other things, including cortisol and thyroid antibodies.
She said if it's still low she will refer me to an endo.
Next lot of blood tests are on Friday. She said I need to go first thing.
Star - that sounds good. I had a cortisol response test. I don't know what my resting cortisol was but the response doubled. (This has to be done at hospital) but I'm pleased the GP is actually starting a ball rolling. And good on antibodies.
I'm not sure about your other questions. Many people on thyroxine could plot a comparative level thing but that's because the thyroxine is static as externally taken. So easy to chart comparative changes. I can say "at this number I feel xyz." There's more subtlety going on in a functioning thyroid feed back system, including some t3 made by the thyroid itself. (As I understand it)
I know that Nice have noted that there's an increased risk of mc if Tsh is over 2.5 in anyone.
There is a gentle circadian rhythm of all thyroid things so always try for the morning.
The antibodies are key I feel as if they're present there could be something going on. Also, I think antibodies could appear in the future if not currently present ( I was told recently regarding coeliac disease this happens and going to be having another check as my iron has dropped considerably) so it would not be unreasonable to request in the future if this is clear.
I once had a TSH of 1.53 and a FT4 of 10.4 which added weight to my suspicions of pituitary involvement. However TSH has risen over the years since then.
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