Celiac Disease testing

[Heamic08]

Hello!

I’m new to this since they think I may have Celiac Disease. I had an endoscopy done on Friday and they did biopsies for Celiac, but of course don’t have those back yet.

Blood results:

Endomysial Antibody IgA- negative

t-Transglutaminsae (tTG) IgA- 7 (weak positive)

Immunoglobulin A, Qn, Serum- 201

What do these blood test results mean? My symptoms have been nausea, vomiting, stomach cramps/pain. It’s been going on since Thanksgiving, and a little before then.

 

Thanks!

[plumbago]

You posted results of two blood tests for Celiac disease. One is negative and one is positive. Generally, it only takes one positive result to diagnose Celiac. It is highly likely that you have Celiac disease.

The two tests you posted measure the amounts of immunoglobulin A and not the more numerous immunoglobulin G. It's complicated, but generally, your positive test for t-Transglutaminsae (tTG) IgA means that you are producing enough of this antibody to indicate short-term immune response; ingestion of gluten 2-4 weeks preceding the test. There is another test (immunoglobulin G). It is a marker of more long-term ingestion of gluten, if positive. You did not post results of that, not sure if you had that tested or not.

The t-Transglutaminsae (tTG) IgA test that you did is not 100% specific: there are other causes of a positive test, but in general it's fairly reliable.

The other test you did measures the total amount of immunoglobulin A circulating in your blood. Had that been low, it would effectively invalidate the t-Transglutaminsae (tTG) IgA test because you simply didn't have enough to measure. But your result for total IgA seems normal to me.

[Heamic08]

  On 12/11/2023 at 9:50 PM, plumbago said:

You posted results of two blood tests for Celiac disease. One is negative and one is positive. Generally, it only takes one positive result to diagnose Celiac. It is highly likely that you have Celiac disease.

The two tests you posted measure the amounts of immunoglobulin A and not the more numerous immunoglobulin G. It's complicated, but generally, your positive test for t-Transglutaminsae (tTG) IgA means that you are producing enough of this antibody to indicate short-term immune response; ingestion of gluten 2-4 weeks preceding the test. There is another test (immunoglobulin G). It is a marker of more long-term ingestion of gluten, if positive. You did not post results of that, not sure if you had that tested or not.

The t-Transglutaminsae (tTG) IgA test that you did is not 100% specific: there are other causes of a positive test, but in general it's fairly reliable.

The other test you did measures the total amount of immunoglobulin A circulating in your blood. Had that been low, it would effectively invalidate the t-Transglutaminsae (tTG) IgA test because you simply didn't have enough to measure. But your result for total IgA seems normal to me.

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Thank you so much for this information! Those were the only tests I had done (besides the endoscopy biopsies). Hopefully I can know the biopsies sooner rather than later, but I’m trying to start a gluten free diet.

[trents]

Welcome to the forum, @Heamic08!

Celiac disease produces inflammation in the villous lining of the small bowel when gluten is ingested. This inflammation produces antibodies that can be detected in the blood. The tests you list above are measuring antibody levels. The first two, Endomysial Antibody IGA (or just "EMA" for short) and tTG-IGA, are tests designed to check for antibodies that are specific to celiac disease as opposed to inflammation caused by other things and in other parts of the body. The Immunoglobulin A, Qn, Serum is a measure of the total IGA count in the blood including but not limited to the EMA and the tTG-IGA. The total IGA is helpful in that if it is below normal range it can cause the EMA and the tTG-IGA to be falsely low and potentially cause a false negative when they are marginally high to begin with. Your total IGA is in normal range so that is not an issue in your case. EMA is test that was developed early on to detect celiac antibodies. It is highly specific for celiac disease but not very sensitive and is expensive to run. The tTG-IGA came later and has good specificity and good sensitivity. It is the most popular test ordered by physicians checking for celiac disease and is cost effective. Since your tTG-IGA was weakly positive and you have symptoms that align with celiac disease, you were referred to the stage two diagnosis (endoscopy with biopsy) to actually examine the villous lining of the small bowel for inflammatory damage.

[Heamic08]

  On 12/11/2023 at 9:59 PM, trents said:

Welcome to the forum, @Heamic08!

Celiac disease produces inflammation in the villous lining of the small bowel when gluten is ingested. This inflammation produces antibodies that can be detected in the blood. The tests you list above are measuring antibody levels. The first two, Endomysial Antibody IGA (or just "EMA" for short) and tTG-IGA, are tests designed to check for antibodies that are specific to celiac disease as opposed to inflammation caused by other things and in other parts of the body. The Immunoglobulin A, Qn, Serum is a measure of the total IGA count in the blood including but not limited to the EMA and the tTG-IGA. The total IGA is helpful in that if it is below normal range it can cause the EMA and the tTG-IGA to be falsely low and potentially cause a false negative when they are marginally high to begin with. Your total IGA is in normal range so that is not an issue in your case. EMA is test that was developed early on to detect celiac antibodies. It is highly specific for celiac disease but not very sensitive and is expensive to run. The tTG-IGA came later and has good specificity and good sensitivity. It is the most popular test ordered by physicians checking for celiac disease and is cost effective. Since your tTG-IGA was weakly positive and you have symptoms that align with celiac disease, you were referred to the stage two diagnosis (endoscopy with biopsy) to actually examine the villous lining of the small bowel for inflammatory damage.

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Thank you for this information!! I’m anxious to find out what my endoscopy biopsy results are…

[trents]

@Heamic08, keep us posted. There is another gluten disorder known as NCGS (Non Celiac Gluten Sensitivity) which is a possibility if you have established the fact that gluten is causing you problems. NCGS shares many of the same symptoms as celiac disease but does not damage the villous lining of the small bowel. It is 10x more common than celiac disease and also requires complete abstinence from gluten. It can do damage to other parts of the body, especially things that fall under the category of neurology. Some experts feel that NCGS can be a precursor to celiac disease. 

[Heamic08]

  On 12/11/2023 at 10:26 PM, trents said:

 

 

@Heamic08, keep us posted. There is another gluten disorder known as NCGS (Non Celiac Gluten Sensitivity) which is a possibility if you have established the fact that gluten is causing you problems. NCGS shares many of the same symptoms as celiac disease but does not damage the villous lining of the small bowel. It is 10x more common than celiac disease and also requires complete abstinence from gluten. It can do damage to other parts of the body, especially things that fall under the category of neurology. Some experts feel that NCGS can be a precursor to celiac disease. 

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Wow! Never knew that! Thanks for telling me. I’ll look into that as well!

[Scott Adams]

This article might be helpful. It breaks down each type of test, and what a positive results means in terms of the probability that you might have celiac disease.