Can H Pylori cause elevated tTG-IgA levels?

[Mike T]

Does anyone have any experience with misdiagnosis of celiac disease when it comes to having an H Pylori infection found at the same time? I had a tTG-IgA blood test as part of some extensive testing I am having. That came back slightly high. I had a biopsy and was then told to go Gluten free (before the results came back). During the endoscopy however they found H Pylori so I was immediately started on the eradication antibiotics for that. So my eradication therapy for H Pylori and gluten-free diet started at the same time. I have never had any symptoms of celiac disease nor have I felt any change to anything since going gluten-free. My biopsy came back without conclusive signs of celiac disease. My tTG-IgA blood tests that were done subsequently (after some weeks/months on gluten-free diet) did come down into the normal range. One was done two weeks into H Pylori eradication and had come down to a nearly normal level but still high. Then another test a couple of months later was within the normal range. Are there any examples of conditions such as H Pylori causing false positive Celiac tTG-IgA blood results, as my antibodies did seem to fall, in line with the two week eradication therapy for H Pylori. A confusing picture as they also told me to go gluten-free at the same time as this eradication antibiotic started.

[trents]

Welcome to the forum, Mike T!

There are a few things that can cause elevated tTG-IGA besides celiac disease but H. Pylori is not one of them that I know of. As you say, given the timing of your going gluten free, is impossible at this point. My recommendation for you is that when you get the H. Pylori under control is to go back to eating regular amounts of gluten (two slices of wheat toast per day or the gluten equivalent, according to the Mayo Clinic) for two months and then repeat the testing for celiac disease. This should be doable since you weren't having symptoms anyway.

[Scott Adams]

Can you share your blood test results with us, including the reference ranges?

[Mike T]

Thanks yes, the ref range for the test was 0-7 unit/ml and my first result before starting gluten-free diet or H Pylori eradication therapy was 19 unit/ml. (My haematologist advised I start gluten-free diet once I had had the biopsy even before the results of the biopsy, so I did). Then two weeks after starting gluten-free diet and H Pylori treatment it was 13 unit/ml then 6.7 unit/ml a few weeks later. The biopsy result was not suggestive of celiac disease. Thanks in advance! 

[Russ H]

I had a quick literature search and couldn't find anything for adults. In children I found one study that was equivocal but another that suggested H. pylori could cause a rise in IgA-tTG2 antibody levels. Your level was only moderately raised - when 10x standard range or higher, it is almost certainly coeliac disease. Adhering to a strict gluten-free diet is very burdensome, so you might want to verify that you have the condition. The only way I can see is to go back on gluten and see whether your symptoms and raised antibody levels return.

https://pubmed.ncbi.nlm.nih.gov/33895735/

[Scott Adams]

22 hours ago, Mike T said:

Thanks yes, the ref range for the test was 0-7 unit/ml and my first result before starting gluten-free diet or H Pylori eradication therapy was 19 unit/ml. (My haematologist advised I start gluten-free diet once I had had the biopsy even before the results of the biopsy, so I did). Then two weeks after starting gluten-free diet and H Pylori treatment it was 13 unit/ml then 6.7 unit/ml a few weeks later. The biopsy result was not suggestive of celiac disease. Thanks in advance! 

Which type of celiac disease test was this? I ask because the accuracy of a diagnosis can vary some depending on the type of blood test given.

Also, it's important to understand the cause of your H. pylori infection. I had H. pylori at the time of my celiac disease diagnosis as well, and in my case the likely cause of H. pylori was the damage done by my untreated celiac disease. Many other members of this forum have reported a similar pattern, than H. pylori can be triggered by celiac disease.

[Mike T]

It was the tissue transglutaminase ttg-iga test. Thanks. Both My GI and the nurse told me that H Pylori is very common (50% of general population people have it) often without problems.

[trents]

35 minutes ago, Mike T said:

It was the tissue transglutaminase ttg-iga test. Thanks. Both My GI and the nurse told me that H Pylori is very common (50% of general population people have it) often without problems.

Probably everyone has H. Pylori it's just a question of is it in balance and in check with regard to the millions of other kinds of microbiota in the gut.

[Scott Adams]

For your reference, this article might be helpful...so the odds you don't have celiac disease with a positive ttg-iga test are about 10%:

Quote

The test is estimated to have a sensitivity of approximately 90%, which means that it correctly identifies 90% of people with celiac disease. It also has a high specificity of around 95%, which means that it correctly identifies 95% of people who do not have celiac disease.