Test Results How Reliable?

[TomBone 0]

Hi all, happy to find this forum!

In the last few months I've had stomach & digestion issues and wanted to check whether it has anything to do with gluten.

I used to eat at least 2 loafs of bread every day as well as other products which seem to have gluten (beer, cookies, soy sauce, etc.).

The doc I asked for a test, made me do four different tests (sorry if the test names are not 100% correct, I'm trying to translate them from Spanish):

 

Antic. Anti endomysial IgA - negative
Antic. Anti endomysial IgG - negative
Transglutaminasa IgG - 9.7U/ml (positive above 10)
Transglutaminasa IgA - 8.3U/ml (positive above 10)

Now, I'm wondering what exactly those results mean. On first sight, they are negative, but Transglutaminasa IgG is very close to the threshold. In fact, I stopped eating bread around 2 weeks before the test (but occasionally had things with gluten) and didn't drink beer for more than 2 months. Could the values have dropped just below the threshold because of that?

How high are valued typically if you have celiac disease? Would they be well over 10U/ml?

I'm hesitant to do any additional testing due to the high cost (my insurance refuses to cover it).

 

Also, from what I've read it's possible to be gluten intolerant but celiac disease negative? Are the negative effects on the gut similar in both cases or is it health-wise ok to eat gluten if intolerant?
Sorry for the very basic questions but I'm pretty new to all this and find the available information quite confusing...

 

[nvsmom 334]

I like to refer to this report when discussing test reliability: http://www.worldgastroenterology.org/assets/export/userfiles/2012_Celiac%20Disease_long_FINAL.pdf 

On page 12 it shows the sensitivity of the EMA IgA and tTG IgA, which is the likelihood of the disease being caught by the test.  Both tests can miss up to 25% of celiacs with a sensitivity of 75-100% and 75-95%. They are pretty good tests for most celiacs.

 

The endomysial tests (EMA) are similar to the tTG tests but they tend to detect more advanced disease.  If you are relatively new to celiac disease, it is possible to get a positive tTG with a negative EMA.  It is very unusual for a celiac to get a positive EMA with a negative tTG though.

 

The tTG IgG is not a very sensitive test.  It's sensitivity is as low as 40% which means it can miss the majority of celiacs.  This report discusses it a bit: http://www.jfponline.com/index.php?id=22143&tx_ttnews[tt_news]=172034

 

Your tTG results are both fairly close to being positive and I would be suspicious too.  You might want to request the DGP IgA and DGP IgG (deaminated gliadin peptides) tests.  Those tests are the best for detecting early celiac disease and sometimes catch cases of celiac disease that the tTG tests do not.  

 

Make sure you are eating gluten in the 2-3 months prior to testing.

 

Another option is the biopsy.

 

If you can't get further testing, or the tests are negative, you should be retested every year or so if you continue to eat gluten.  If you decide to go gluten-free anyways, further testing is not crucial.

 

Best wishes and welcome to the board.  

[TomBone 0]

Nicole, I appreciate your reply and link to the report. I will check with my doctor if they can do DGP tests here.

[nvsmom 334]

Good luck!