# TSI vs. TrAb?



## bluesmom (Aug 11, 2012)

I had asked my endo to test for TSI because my TgAb and TPO were so high and I have several symptoms which seem more hyper than hypo. She tested for TrAb instead and the nurse said because that test was negative, my TSI would be negative as well. Is this correct? All she could tell me about my TrAb result is that it's <1 and she thinks the range might be <1.22 or <1.58.
Thanks,
Carolyn


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## Andros (Aug 26, 2009)

bluesmom said:


> I had asked my endo to test for TSI because my TgAb and TPO were so high and I have several symptoms which seem more hyper than hypo. She tested for TrAb instead and the nurse said because that test was negative, my TSI would be negative as well. Is this correct? All she could tell me about my TrAb result is that it's <1 and she thinks the range might be <1.22 or <1.58.
> Thanks,
> Carolyn


Not necessarily correct. Trab is the thyroid stimulating hormone receptor antibody as you well know. This is in an attempt to off set the action of the TSI.

However, you do have Trab. Just because it is below the range does not mean you do not have it. You should have no evidence of Trab period if all was well in La La Land.

All antibodies wax and wane. They can be low and then high, then low again and so on.

Substances not found in normal serum
http://www.thyroidmanager.org/Chapter6/Ch-6-6.htm

It would be a good idea to press hard for TSI.

Trab
http://www.ncbi.nlm.nih.gov/pubmed/17684583

http://www.ncbi.nlm.nih.gov/pubmed/14969154

Kronus® TRAb radioreceptor assay (TRAb) to our test menu to reduce the number of requests for TSI. During the preimplementation evaluation of the Kronus reagents, we found equivalent results in 80 of 89 random patient samples. Of the remaining nine samples, five were positive by TSI and not by TRAb, and four were positive by TRAb and not by TSI.

please read entire abstract.

http://www.clinchem.org/content/49/8/1402.full

If our disease doesn't kill us, the medical establishment will!


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## bluesmom (Aug 11, 2012)

Wow, thank you SO MUCH Andros! Those articles, particularly the last abstract, were very enlightening. I'm so frustrated that they didn't just test for TSI as I requested!!!
I had already asked my PCP to do the TSI and he refused, suggesting that the endo should be the one to order it. The endo has now refused to order it because of the result of the TrAb. Wonderful (sarcasm). I've also been taking 50mg synthroid for 3 weeks now with no symptom relief (and some new ones - like heartburn, increased diarrhea). Though on the third day of synthroid, I had one great day and felt less pain in my neck and shoulder than any other day in many many years. Maybe after 3 more weeks of synthroid, that relief will come back? Somehow I doubt it. 
Will the synthroid affect a TSI result if I can find someone to order a blood test?
Thanks again for all you help,
Carolyn


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## Andros (Aug 26, 2009)

bluesmom said:


> Wow, thank you SO MUCH Andros! Those articles, particularly the last abstract, were very enlightening. I'm so frustrated that they didn't just test for TSI as I requested!!!
> I had already asked my PCP to do the TSI and he refused, suggesting that the endo should be the one to order it. The endo has now refused to order it because of the result of the TrAb. Wonderful (sarcasm). I've also been taking 50mg synthroid for 3 weeks now with no symptom relief (and some new ones - like heartburn, increased diarrhea). Though on the third day of synthroid, I had one great day and felt less pain in my neck and shoulder than any other day in many many years. Maybe after 3 more weeks of synthroid, that relief will come back? Somehow I doubt it.
> Will the synthroid affect a TSI result if I can find someone to order a blood test?
> Thanks again for all you help,
> Carolyn


I am not sure if the Synthroid will affect the blood draw. My tendency is to think not.

You could call here and inquire if you have one in your area.

HealthCheckUSA
http://www.healthcheckusa.com/

It is my humble pleasure!


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