rT3: I've just had some more bloods done, this... - Thyroid UK

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reelingenious profile image

I've just had some more bloods done, this time "ultravit rT3.

The comment drew attention to the FT3/rT3 "abnormal" ratio............i.e., 12.99!

It also added. "you may wish to discuss these results with your GP, although you should note that it may be difficult to get advice and treatment for elevated rT3, or an abnormal ratio, through conventional channels”.

I have to assume therefore , there is a reluctance to accept the relevance of this ratio.

I have an appointment this Friday with a "General Consultant". Are there any arguments, published papers etc.,? MY symptoms fir the bill, but I have to, so have my other theories. But at least this an anomaly, and few of them have been thrown up!!

5 Replies
shaws profile image

There's no history in your profile so am assuming you are hypothyroid and taking levothyroxine? What dose?

We would be better able to help you if you actually posted all the results, with their ranges. Otherwise, it's like groping in the dark.

Was your rT3 over-range? If so, was your FT4 high in range? If not, your thyroid hormones have nothing to do with thyroid hormones, and the rT3 ratio would be spurious to say the least.

As far as anyone knows, there is no relevance of this ratio - and GPs would be the last to know if there were! For a start, it's not a true ration because it doesn't compare like with like. rT3 is a total test, containing both Free rT3 and bound rT3. The FT3 is just what it says: Free. It's false science, and an attempt to justify the rT3 test itself. If your rT3 is high, and your FT3 is low, of course your rT3 ratio is going to be low/below range. But, that's not taking FT4 into consideration, so says nothing about your conversion.

The rT3 test is one of those tests that tells you if you have a problem, but doesn't tell you were the problem is. However, if you know you have high FT4 and low FT3, you know you have a conversion problem, and therefore will have high rT3. However, if you have low FT4 and high rT3, there there could be any number of reasons for it : low iron, high/low cortisol, an infection, starvation diet, to name just a few. Most of those things you will be aware of anyway, so not much point in doing an rT3 test.

But, GPs will be blissfully unaware of any other this, how to read the results or any possible significance. So, not much point doing the tests, then, really, is there. :)

I little surprised there is no history, but no mind. I have been chasing a definitive diagnosis for Hypo symptoms for years and getting nowhere as all other levels, TSH etc., have always been `"within range". Taking no medication.

TSH = 2mIU/L (0.27 - 4.2.) Free T3 = 3.99 pmol/L (3.1 - 6.8) . rT3 = 20ng/dl (10. - 24). rT3 Ratio 12.99 (15.01 - 75).

As I posted out in my original post, the significance of rT3 ratio is subject to much conjecture. It may not be worth pursuing then? As with much information available on the net, it sounds logical!!!

If you're interested in learning more about rT3 and the ratio, you should read this page: tiredthyroid.com/rt3.html

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