Celiac Test Results - Thoughts?

[hmkr]

I had several celiac blood tests done at a rheumatologist last month. I've had many possible symptoms over the last 23 years, including GERD/LPR, constipation, and recently joint stiffness and pain in my hands. It all started during my first pregnancy. 1/160 ANA back then as well as now with no autoimmune diagnosis. I've had undiagnosed high fevers, swollen lymphs nodes, ear pain, miscarriages, to name just a few more symptoms. I can't help but be upset at the many doctors I've been to that have missed this. A GI doctor only did the IgA 5 years ago, which was negative then too, and didn't do a biopsy as a result during an endoscopy shortly after.

Deaminated Gliadin IgG Antibody test was 90, >15 being abnormal.  

Deaminated Gliadin IgA Antibody, negative

Tissue Transglutaminase IgG Antibody, negative

Tissue Transglutaminase IgA Antibody, negative

I'm scheduled for a biopsy at the end of January. The new GI doctor thinks if not celiac, I will still need to be gluten free the rest of my life due to the antibodies my body is producing. I feel like it's got to be celiac. I've been consuming gluten every day to prepare for this test. It can't come soon enough. 

Thoughts on that IgG being positive and the others negative? I haven't gotten a clear explanation for that yet.

Thanks in advance for any input!! 

[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. One test that always needs to be done is the IgA Levels/Deficiency Test (often called "Total IGA") because some people are naturally IGA deficient, and if this is the case, then certain blood tests for celiac disease might be false-negative, and other types of tests need to be done to make an accurate diagnosis. The article includes the "Mayo Clinic Protocol," which is the best overall protocol for results to be ~98% accurate.

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The sensitivity of the DGP-IgG test is reported to range from 75% to 85%, which means it can correctly identify individuals with the condition in about 75% to 85% of cases. The specificity of the DGP-IgG test is reported to range from 75% to 95%, which means it can correctly identify individuals without the condition in about 75% to 95% of cases. Overall, the DGP tests, including DGP-IgA and DGP-IgG, exhibit a sensitivity of approximately 85-95% and a specificity of about 95-98%.

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I agree that if your biopsy ends up negative, that you still may need to be gluten-free, as you could be in the non-celiac gluten sensitivity area. Approximately 10x more people have non-celiac gluten sensitivity than have celiac disease, but there isn’t yet a test for NCGS. If your symptoms go away on a gluten-free diet it would likely signal NCGS.

Be sure to eat lots of gluten daily until your endoscopy, otherwise you could get false negative results.

 

 

[trents]

When you say a GI doc did an IGA five years ago and it was negative, which IGA measure do you speak of. There are several possibilities. Do you refer to the tTG-IGA?

Have you had a total IGA test done? It isn't a test for celiac per se but can establish whether or not you are IGA deficient. If you are IGA deficient, it will drive individual IGA test scores down and can result in false positives. The tTG-IGA should always be accompanied by a total IGA test.

When people are IGA deficient and actually do have celiac disease we often see it detected by the IGG tests. The same can be said if they have been skimping on gluten previous to the blood draw and, IMO, negatives in the IGA test spectrum with positives in the IGG spectrum can also point to NCGS or NCGS transitioning to celiac.

Edited December 27, 2024 by trents

[hmkr]

  On 12/27/2024 at 12:27 AM, trents said:

When you say a GI doc did an IGA five years ago and it was negative, which IGA measure do you speak of. There are several possibilities. Do you refer to the tTG-IGA?

Have you had a total IGA test done? It isn't a test for celiac per se but can establish whether or not you are IGA deficient. If you are IGA deficient, it will drive individual IGA test scores down and can result in false positives. The tTG-IGA should always be accompanied by a total IGA test.

When people are IGA deficient and actually do have celiac disease we often see it detected by the IGG tests. The same can be said if they have been skimping on gluten previous to the blood draw and, IMO, negatives in the IGA test spectrum with positives in the IGG spectrum can also point to NCGS or NCGS transitioning to celiac.

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The IGA tests 5 years ago were:

Transglutaminase IGA (EMY IGA) (CENT-tTG), <2

Immunoglobulin A (CENT-IGA), 246

IgA Quantitative was done last month, that was 261. Is that the one you mean?

 

[trents]

Yes, that's the one. IGA Quantitative. What is the reference range given for that one? If no reference range was given, is there another notation associated with it indicating it was either low or high or neither? If not, I would assume your score does not indicate IGA deficiency.

Edited December 27, 2024 by trents

[hmkr]

  On 12/27/2024 at 1:35 AM, trents said:

Yes, that's the one. IGA Quantitative. What is the reference range given for that one? If no reference range was given, is there another notation associated with it indicating it was either low or high or neither? If not, I would assume your score does not indicate IGA deficiency.

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Normal range: 70 - 400 mg/dL, a little above middle of the range. So what does that mean?

  On 12/27/2024 at 12:27 AM, Scott Adams said:

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. One test that always needs to be done is the IgA Levels/Deficiency Test (often called "Total IGA") because some people are naturally IGA deficient, and if this is the case, then certain blood tests for celiac disease might be false-negative, and other types of tests need to be done to make an accurate diagnosis. The article includes the "Mayo Clinic Protocol," which is the best overall protocol for results to be ~98% accurate.

I agree that if your biopsy ends up negative, that you still may need to be gluten-free, as you could be in the non-celiac gluten sensitivity area. Approximately 10x more people have non-celiac gluten sensitivity than have celiac disease, but there isn’t yet a test for NCGS. If your symptoms go away on a gluten-free diet it would likely signal NCGS.

Be sure to eat lots of gluten daily until your endoscopy, otherwise you could get false negative results.

 

 

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Thank you! I will check out that page you linked. Appreciate it! 

[trents]

It just means you aren't IGA deficient, i.e., that IGA deficiency cannot have given you artificially low scores in the individual IGA celiac antibody tests. This is explained in the article Scott linked above.

Edited December 27, 2024 by trents

[hmkr]

  On 12/27/2024 at 4:42 AM, trents said:

It just means you aren't IGA deficient, i.e., that IGA deficiency cannot have given you artificially low scores in the individual IGA celiac antibody tests. This is explained in the article Scott linked above.

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Ok, interesting. Not what I was thinking that meant. I'm reading the article and trying to understand.

I see this “According to the latest research, if the blood test results are at certain high levels that range between 5-10 times the reference range for a positive celiac disease diagnosis, it may not be necessary to confirm the results using an endoscopy/biopsy” My IgG is 90, which is 6 times. So to me that means it's highly likely I do have it. 

[trents]

Yes, there is a trend in the medical community to forego the endoscopy/biopsy and grant an official celiac diagnosis based on high tTG-IGA antibody scores alone. This trend started in the UK and is spreading to the USA medical community. And yes, 5-10x the normal level is what I have been seeing as the threshold as well. Here is the relevant section dealing from the article above dealing with the importance of the total IGA test being ordered. See the embedded attachment.