Only Positive for Anti Gliadine IgA

[tomraynor]

Hello,

First time posting here, been reading some posts on the forum and it seems I have come to the right place for help as lots of helpful people on here.

I have been having gut issues for a very long time, I've done colonoscopies, gastroscopies etc... but nothing major was flagged. However I recently did a celiac panel blood test and had the following results:

- Negative for Anti Tissue Transglutaminase Antibodies IgA

- Negative for Anti Tissue Transglutaminase Antibodies IgG

- Negative for Anti Gliadine IgG
- Positive for Anti Gliadine IgA - result is 30 when the reference is more than 18

My biopsy from my gastroscopy was negative for celiac but at the time they were not specifically looking to see if I have Celiac Disease which I think they would have taken more biopsies.

 

Given that only Anti Giladine IgA is positive and everything else is negative, my dr wants me to do a HLA genetic test, but its costly. 

My questions are the following:

- Based on my results how likely is it that I have Celiac Disease?

- Is the HLA test worth it?

Thanks!

Tom

[trents]

Were you still consuming gluten daily when the panel was done? Many people make the mistake of already having started a gluten-free diet before they go for the testing. And most docs fail to tell them not to do that.

The HLA test only checks for genetic celiac disease potential. It doesn't prove you have active celiac disease. Most people who have the genes don't develop it. However, if someone has a first degree relative with celiac disease then there is a 44% chance they will also have it.

[Scott Adams]

This article is older, but explains the tests you took well: “IgA anti-gliadin antibodies are less sensitive but are more specific. In clinical trials, the IgA antibodies have a specificity of 97% but the sensitivity is only 71%. That means that, if a patient is IgA positive, there is a 97% probability that they have celiac disease. ”

 

[tomraynor]

16 hours ago, trents said:

Were you still consuming gluten daily when the panel was done? Many people make the mistake of already having started a gluten-free diet before they go for the testing. And most docs fail to tell them not to do that.

The HLA test only checks for genetic celiac disease potential. It doesn't prove you have active celiac disease. Most people who have the genes don't develop it. However, if someone has a first degree relative with celiac disease then there is a 44% chance they will also have it.

I cant remember back then, but I have never been 100% gluten free, I will still eat bread etc..

So is the DNA test pointless? Unless of course it shows I dont have the genes then I can at least know that I dont have Celiac

[tomraynor]

14 hours ago, Scott Adams said:

This article is older, but explains the tests you took well: “IgA anti-gliadin antibodies are less sensitive but are more specific. In clinical trials, the IgA antibodies have a specificity of 97% but the sensitivity is only 71%. That means that, if a patient is IgA positive, there is a 97% probability that they have celiac disease. ”

 

thanks for sharing this article, very informative. So the question I would have is why would I only test postive for Anti Giladin IGa and not for anything else such as Anti Tissue Transglutaminase Antibodies? Also I read in the article that anti-endomysial antibodies are very specific, wouldnt this be the best test to determine if someone definitely has celiac disease?

[trents]

The point is that the TTG_IGA is the most specific for celiac disease but not the most sensitive test, which will result in some who actually do have CS celiac disease being missed. The other tests are less specific for celiac disease but more sensiitve, which means they might point to celiac disease or to other diseases of the intestinal track such that the patient might receive a diagnosis of celiac disease when it was actually something else causing the problems. That's why it's a good idea to get "full celiac panel" when you get the blood test. That way you have a better chance of detection while minimizing the possibility of getting a false diagnosis of celiac disease. So if the TTG_IGA misses it and other tests detect a problem you would need to consider celiac disease but also other possible bowel diseases. That's my take on it.

Edited March 1, 2021 by trents
typo

[Scott Adams]

I agree with @trents, and false positives are not common with any of these tests, especially this one. False negative results are more common, due to many reasons, mainly that some people go gluten-free before they get their blood test done.

[tomraynor]

16 hours ago, Scott Adams said:

I agree with @trents, and false positives are not common with any of these tests, especially this one. False negative results are more common, due to many reasons, mainly that some people go gluten-free before they get their blood test done.

thank you and @trents for the explanation, however given what Trents said, that it could be something else that is causing the non TTA_IGA result to be within the positive range and not specifically Celiac Disease, so based on my rest results I cant definitively 100% say I have Celiac Disease. What would be the best possible next test to get done?

[trents]

Quoting from Scott's post above where he quotes from the article: “IgA anti-gliadin antibodies are less sensitive but are more specific."

If that one was positive, then it would seem to strongly point to celiac disease rather than something else because of it's specificity. The next step in confirmation would be the endoscopy/biopsy or alternatively, commit to eating gluten free and see if you feel better. My hesitation with the latter is that there is a learning curve with regard to eliminating gluten from the diet and some people will drop out of the effort before getting to the point where they are truly eating gluten free and not just eating lower gluten. You may not feel much better until you can get to the point where gluten is really gone from the diet. That's where the confirmation from an endoscopy/biopsy has value. It can strengthen the resolve and eliminate second guessing.

There are some other medical conditions, some medications and even some non gluten food intolerances/allergies that can mimic celiac disease but start with what is most likely causing your problems, i.e. celiac disease.

Edited March 2, 2021 by trents