My son has been ill for several years with no diagnosis but over the last year, his T4 levels have been slightly raised at 21/22. Before they were 17/18.
He has just about every symptom of hyperthyroidism that' are listed, feels so dreadful and is unable to do anything, and yet his FT4 is barely raised above the top of the range.
His TSH is normal at 1.5 and was also 1.5 when his FT4 was 17/18.
Is it possible to feel so bad with such a minimal rise in FT4, or do you think we should be looking for another illness for this FT4 rise?
Thanks very much.
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miklaw0402
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For full Thyroid evaluation you need TSH, FT4 and FT3 plus both TPO and TG thyroid antibodies tested. Also EXTREMELY important to test vitamin D, folate, ferritin and B12
Low vitamin levels are extremely common, especially if cause is Graves’ disease (Hyperthyroid) or have autoimmune thyroid disease (Hashimoto's) - hypothyroid
You may need to get full Thyroid testing privately as NHS refuses to test TG antibodies if TPO antibodies are negative
GP often unable to test TSI or Trab antibodies. Has to be done by endocrinologist
Recommended on here that all thyroid blood tests should ideally be done as early as possible in morning and before eating or drinking anything other than water .
This gives highest TSH, lowest FT4 and most consistent results. (Patient to patient tip, best not mentioned to GP or phlebotomist)
Private tests are available. Thousands on here forced to do this as NHS often refuses to test FT3 or antibodies
Medichecks Thyroid plus ultra vitamin or Blue Horizon Thyroid plus eleven are the most popular choice. DIY finger prick test or option to pay extra for private blood draw. Both companies often have special offers, Medichecks usually have offers on Thursdays, Blue Horizon its more random
If you can get GP to test vitamins and antibodies then cheapest option for just TSH, FT4 and FT3 £29 (via NHS private service )
If TPO or TG antibodies are high this is Hashimoto's, (also known by medics here in UK more commonly as autoimmune thyroid disease). can also be slightly high with Graves
About 90% of all primary hypothyroidism in Uk is due to Hashimoto's.
Low vitamins are especially common with Hashimoto's and Graves . Food intolerances are very common too, especially gluten.
So it's important to get TPO and TG thyroid antibodies tested at least once .
Hyperthyroidism is raised FT3, not FT4. And symptoms are caused by T3 when it's either too high or too low. Difficult to imagine that his FT3 would be high enough to cause hyper symptoms with that FT4. But, it could be that even though his FT4 is high - quite how high we don't know, because you haven't given us the range - he isn't converting T4 to T3 very well, and his FT3 is low.
What sort of symptoms is he having? Because a lot of thyroid symptoms are the same for hypo and for hyper.
So, his FT4 is only slightly over-range, his TSH is euthyroid, and his FT3 is well in-range. So, no indication of either hypo or hyper status.
All those symptoms could be either hypo or hyper. Or from something entirely different.
I take it he doesn't have any sort of diagnosis? Has he been tested for anything other than thyroid? Nutrients, for example? Kidneys? Liver?
How about antibodies? Have any antibodies been tested for? I'm not medically trained, and only know about thyroid because I have Hashi's, so I am unable to suggest what else might be wrong with him - because something obviously is. But, it does seem to me that antibody testing is essential.
TPO & Thyroid antibodies have both come back negative. Graves antibodies haven't been tested yet.
It just seems odd that all those symptoms should either increase substantially or begin at the exact same time as the FT4 rises. And whilst it's only slightly elevated, an increase from 17 to 22 doesn't feel insignificant.
I also forgot to mention in the first post that had had a swelling on the right side of his neck that had been increasing in size until all this happened, and suddenly shrunk down to normal as all the symptoms became very pronounced. His neck circumference went up, and then down, by 1.5 inches.
If it's not thyroid related, what other illnesses can increase levels of FT4, and why would the TSH barely move even after the FT4 was slightly elevated for 9 months? Wouldn't the TSH be lower, if only somewhat, when the FT4 is at 22 than at 17?
It just seems odd that all those symptoms should either increase substantially or begin at the exact same time as the FT4 rises.
But it's not T4 that causes symptoms. It's T3 that causes symptoms when it's too high or too low. And your FT3 is just over mid-range, so not obviously high or low. Although it might not be the right level for him as an individual.
If it's not thyroid related, what other illnesses can increase levels of FT4,
As I said, I'm not medically trained, but I don't know of any other illnesses that would cause his FT4 to rise. I've never heard of such a thing.
and why would the TSH barely move even after the FT4 was slightly elevated for 9 months? Wouldn't the TSH be lower, if only somewhat, when the FT4 is at 22 than at 17?
The TSH level doesn't just depend on the T4, it's also affected by the T3 level. And, the T3 level hasn't changed much. And, in any case, such a slight change in the FT4 wouldn't have much of an impact on the TSH, it's not that finely tuned.
I really don't think there's much point in doing the TRAB. He's not hyper with a mid-range FT3 and a TSH of 1.5. Nor is his FT4 high enough to suggest Grave's. If he had Grave's, it would be up around 70/80 or something like that.
Have you considered getting his adrenals checked? A 24 hour saliva cortisol test, for example?
Could his symptoms really be either hypo or hyper?
The way he describes feeling (overstimulated, unable to sit still and never relaxed) sounds like it’s too much, not too little of something, and some of his symptoms (weight loss, inability to gain weight, increased appetite, racing thoughts, sweating, shaking, needing to go to the toilet too much) also sounds like it’s an increase, not a decrease of something; like his whole body and metabolism is sped up, which is the opposite of hypothyroid.
If a mildly elevated level of FT4 isn’t enough to indicate much, at what point do you think it would be? For Graves, 70-80 is obviously extremely high, but what if it were something like 30?. Also, what could be the point of having a top of the reference range at 20 if it doesn’t mean anything if you go over it? (This seems to be common with blood tests as quite a few other results have been raised, sometimes 2 or 3 times more than the top of the range, and doctors have just ignored them).
With regards to adrenals – I believe there’s a connection between the adrenal glands and thyroid. Could a problem with the adrenals cause a raised FT4?
Could his symptoms really be either hypo or hyper?
Yes, they could.
If a mildly elevated level of FT4 isn’t enough to indicate much, at what point do you think it would be? For Graves, 70-80 is obviously extremely high, but what if it were something like 30?. Also, what could be the point of having a top of the reference range at 20 if it doesn’t mean anything if you go over it?
T4 is basically a storage hormone. It doesn't do very much. It does not cause hyper symptoms when slightly - or very extremely - over-range. It's not the very high FT4 in Grave's that causes symptoms, it's very high FT3. T3 is the active hormone, and the one that causes symptoms when it's either too high or too low.
If his FT4 were around 30, he'd probably have Hashi's. But, it still wouldn't be the T4 causing the problem.
Ranges are only rough guides, not rigid barriers. And very unsatisfactory guides at that. A lab decides on it's ranges by taking the results of everyone they test in the lab during a certain period, and working out the averages, top and bottom, and taking their range from somewhere within that curve. But, the fact that people only go for blood tests when their ill has got to have an effect on the range, making it less than reliable. No-one know, when setting ranges for TSH, FT4 and FT3, how many people have undiagnosed hypo and hyperthyroidism. Plus, we all have our own individual set points, which no-one knows because we're never tested when we're healthy. Which is why ranges can never be absolute.
The problem with doctors is that they ignore ranges when it suits them, but when it suits them, they make a fuss about a tiny discrepancy. They all have their own agenda.
With regards to adrenals – I believe there’s a connection between the adrenal glands and thyroid. Could a problem with the adrenals cause a raised FT4?
There is a very close connection between the adrenals and the thyroid. When the thyroid is failing, not producing enough hormone, the adrenals take up the slack by producing more cortisol. But, as far as I know, the only thing that can produce T4 is the thyroid gland. So, I rather doubt that an adrenal problem could cause a raised FT4. However, Excess cortisol could produce some of the same symptoms.
But, whatever is causing his symptoms, it is not his level of T4. His FT3 is only around mid-range, so doubtful that thyroid is causing his symptoms. But, just to be on the safe side, have his Grave's antibodies been tested yet?
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