Lab results

Hi. I am new to this site.

Some time ago I did a general medical check-up, including lab tests for all kind of stuff.

Most were good, except for values of FT4 that was a little too high.

Because of this it was ordered an extended lab test for the thyroid panel, with the following results:

* S-TSH 3.1 mU/L (ref 0.2-4.0)
* S-Free-T4 27.2 pmol/L (ref 11.0-23.0)
* S-Free-T3 7.0 pmol/L (ref 3.5-6.5)
* S-Anti-TPO  36 kU/L (ref <100)
* S-TRAS <0.8 U/L (ref <1.0)

So the FT4 and FT3 is somewhat higher than the upper limit of the reference range.

My general practitioner says that this is not a medical issue for me as long as the TSH, Anti-TPO and TRAS is within the reference range, and I have no other explicit symptoms or health problems.

I am quite sure she is right, but I am still not 100% comfortable with having lab results that are outside reference ranges, so I thought I should ask some other with knowledge on the subject for opinions.

[goolarra]

Your doctor seems to be testing quite thoroughly.  I'm impressed that he ordered further tests after your high FT4.  I disagree, however, with his putting so much emphasis on TSH being in range.  TSH is the least important or reliable of the tests, since it's a pituitary hormone.

Both your FT3 and FT4 are a little high, as you pointed out.  However, I agree with your doctor that if you have no hyper symptoms or other health problems, it is not an issue.  It might bear watching through the years, and keep your eyes peeled for any symptoms that might surface.  If you should develop symptoms, and your doctor continues to tell you that there's nothing wrong as long as your TSH is in range, don't believe him.

[goolarra]

Just one more thing...I'm curious about a couple odf your ranges and wondering if this is a country-to-country difference.  Did your FT3 range come from your own lab report?  It's a bit different from what we usually see.  Also, we typically see TPOab range of "less than 20" or "less than 40".  Is "TRAS" "TRab" (thyrotropin receptor antibodies)?

[Urbeka]

Hi. Thanks for your reply!

Yes, the ranges come from the lab report. And yes, I think the units used varies from country to country (this particular is from Norway), and the reference range may vary between the labs.

I also know that conversion between different kind of measures are not straightforward, and has to do with molecular weight. Eg. T4: 12 pmol/L = 0.93 ng/dL = 0.00093 µg/dL due to molecular weight T4: 777 ==> leads to different conversion factors for different types of measures.

You are right about the TRAS, thyroid receptor antibodies.

Again, thanks for your reply. Much appreciated.