Hashimoto's Cause False Positive?

[Bttrfly62]

Much of the literature I've read says the positive blood work can be less reliable when done on someone with an existing autoimmune disease (hashimoto's/graves, type 1 diabetes, rheumatoid arthritis, etc.). I know the endoscopy is still the "gold standard", but I wondered if anyone had positive blood work, only to be ultimately negative as a result of another autoimmune condition? How frequently and how substantially do these other conditions skew the results? 

 

Thanks in advance! 

[SPinch03]

I have Hashimoto's thyroiditis.  Last year I was tested for AGA IgG/IgA as well as tTG IgG/IgA.  My AGA IgG was the only test that was positive, had biopsy and it was negative.  Doctors all pretty much said it was probably a false positive, I'm assuming from having hashimoto's.  I was just retested for DGP IgG/IgA and a repeat of tTG IgG/IgA.... so far my DGP IgG and tTG IgG are normal... just waiting on the IgA's to come back.... I'm scheduled for another endoscopy but now I'm wondering if I should just cancel it... very frustrating but I hope this helps a little bit.  Did you have any labs done?

[Gemini]

The only test that could be affected by other AI diseases are the tTg tests.  The AGA IgA/IgG or the newer version, the DGP, are for reaction to gluten that you consume.  The tTg tests for tissue damage and that can be triggered by Celiac, Hashi's, autoimmune liver disease, etc.)  If you had any of those AI diseases, without Celiac, only the tTg would be affected.  Of course, with Celiac Disease, you may not even trigger any of the blood work, but that does not rule Celiac out. Same with Sjogren's...you can have it and not trip the blood work.  There is other testing that can be done if that happens.

 

I have Celiac, Hashi's, Sjogren's and Reynaud's.  Once I was gluten-free for a year, I retested the Celiac panel and all tests were within normal limits, except my tTg was still high normal. It was within normal limits but almost tripping for positive.  It did not go down to low normal until my thyroid antibodies came down also.  My tTg at diagnosis for Celiac was over 200.

 

Hope this helps!

[Bttrfly62]

I've had IGA (normal range), TTG, Gliadin (deamidated) IGG and IGA (all three positive). I'm just wondering if those could be false/picking up on the hashimoto's.

[cyclinglady]

I would say no. Like Gemini stated, the DPG tests are specific to gluten. Keep eating gluten until all testing is complete. The next step is to do an endoscopy and take at least six samples.

I have Hashi's and had only the DPG Iga test show positive. The rest were negative and yet I had moderate to severe intestinal damage.