Am I coeliac

munch42 · March 15, 2020

Hi I had a blood test which said high Ttg so was sent for a gastroscopy and they took 4 biopsies. I have a letter that says biopsies from the duodenum shows increased intraepithelial lymphocytes and chronic duodenitis so since ttg was raised I suspect she has got coeliac.

Is there no straight answer?

docaz · March 15, 2020

On 3/15/2020 at 10:36 AM, munch42 said:

Hi I had a blood test which said high Ttg so was sent for a gastroscopy and they took 4 biopsies. I have a letter that says biopsies from the duodenum shows increased intraepithelial lymphocytes and chronic duodenitis so since ttg was raised I suspect she has got coeliac.

Is there no straight answer?

Expand Quote

This was exactly the same situation with my son. The high tTG has high specificity and sensitivity and many physicians diagnose just based on high numbers. Even if the biopsy would be completely negative, most physicians would recommend a gluten-free diet because they would consider this an early form of celiac disease.

A genetic test could be added to further confirm because it is impossible to have a negative genetic test and be celiac. If the genetic test would come out negative, the tTG would be false positive but that's very, very rare given the specificity of the test.

The biopsy is often done to confirm the diagnosis. For the biopsy to be conclusive for celiac disease, a specific type of lymphocytes (neutrophils) have to be seen in the intraepithelial layer. In this case, the pathologist has either not specified the cells or in fact there was not an increase in neutrophils. A increase of lymphocytes is seen in duodenitis (inflammation of the small intestine) that very common and is unrelated to celiac disease.

In essence, this is a typical case, where the biopsy did not contribute much to your diagnosis because the positive blood test alone is diagnostic for celiac disease.

Ranchers Wife · March 17, 2020

My understanding is that it is NOT impossible to have a negative genetic test, and have Celiac disease.

It is not likely that someone with a negative genetic test does indeed have Celiac disease. But it is not impossible.

There are some uncommon genetic markers that are not included in the current genetic tests, that indicate a possibility of Celiac disease. If you have, for example, a high tTg antibody, and a positive biopsy, then a negative genetic test should not change the presumption of Celiac disease, and the start of a gluten free diet (once blood antibody and endoscopy testing are completed). If symptoms resolve on a gluten free diet, that provides even stronger assurances that you have a gluten problem.

I am not a doctor, and this is not medical advice.

I think there are a couple of posters to this forum, that have an uncommon genetic marker and confirmed Celiac disease. Hopefully they will contribute to this discussion.

docaz · March 17, 2020

On 3/17/2020 at 4:44 PM, Ranchers Wife said:

My understanding is that it is NOT impossible to have a negative genetic test, and have Celiac disease.

It is not likely that someone with a negative genetic test does indeed have Celiac disease. But it is not impossible.

There are some uncommon genetic markers that are not included in the current genetic tests, that indicate a possibility of Celiac disease. If you have, for example, a high tTg antibody, and a positive biopsy, then a negative genetic test should not change the presumption of Celiac disease, and the start of a gluten free diet (once blood antibody and endoscopy testing are completed). If symptoms resolve on a gluten free diet, that provides even stronger assurances that you have a gluten problem.

I am not a doctor, and this is not medical advice.

I think there are a couple of posters to this forum, that have an uncommon genetic marker and confirmed Celiac disease. Hopefully they will contribute to this discussion.

Expand Quote

You can read here about the various screening methods for celiac disease and you can read towards the bottom that a negative genetic test not only excludes the possibility of having celiac disease but also excludes the possibility of developing it in the future.

https://celiac.org/about-celiac-disease/screening-and-diagnosis/screening/

It is extremely unlikely if not impossible to have positive blood tests, positive biopsy (real positive and not duodenitis) and at the same time negative genetic test.

With positive tTG a genetic test is normally not done because it is assumed positive and genetic tests are normally performed in unclear situations or to screen asymptomatic relatives.

There are people on forums who claim unusual genetic markers and all kind of other unusual combinations but this is not currently supported by actual medical literature.

ravenwoodglass · March 17, 2020

On 3/17/2020 at 4:44 PM, Ranchers Wife said:

My understanding is that it is NOT impossible to have a negative genetic test, and have Celiac disease.

It is not likely that someone with a negative genetic test does indeed have Celiac disease. But it is not impossible.

There are some uncommon genetic markers that are not included in the current genetic tests, that indicate a possibility of Celiac disease. If you have, for example, a high tTg antibody, and a positive biopsy, then a negative genetic test should not change the presumption of Celiac disease, and the start of a gluten free diet (once blood antibody and endoscopy testing are completed). If symptoms resolve on a gluten free diet, that provides even stronger assurances that you have a gluten problem.

I am not a doctor, and this is not medical advice.

I think there are a couple of posters to this forum, that have an uncommon genetic marker and confirmed Celiac disease. Hopefully they will contribute to this discussion.

Expand Quote

I am one of those oddballs. 5 years after diagnosis and healing one of my diagnosed children had their genes tested and was told they couldn't be celiac. That prompted me to get my genes tested and found I have a double DQ9. DQ9 has fairly recently been shown to be associated with celiac. Here is a link to one article but there are more out there.

https://www.sciencedirect.com/science/article/abs/pii/S0198885912000262

We still have a lot to learn about celiac and the genetics related to it. IMHO if someone has positive blood work, relief of symptoms gluten free and a decrease in antibodies on a 6 month follow up that is pretty diagnostic. Doctors are starting to realize this especially with children as false negative biopsies are more commonly possible with them.

docaz · March 17, 2020

On 3/17/2020 at 6:33 PM, ravenwoodglass said:

I am one of those oddballs. 5 years after diagnosis and healing one of my diagnosed children had their genes tested and was told they couldn't be celiac. That prompted me to get my genes tested and found I have a double DQ9. DQ9 has fairly recently been shown to be associated with celiac. Here is a link to one article but there are more out there.

https://www.sciencedirect.com/science/article/abs/pii/S0198885912000262

We still have a lot to learn about celiac and the genetics related to it. IMHO if someone has positive blood work, relief of symptoms gluten free and a decrease in antibodies on a 6 month follow up that is pretty diagnostic. Doctors are starting to realize this especially with children as false negative biopsies are more commonly possible with them.

Expand Quote

If I read the abstract correctly (because I do not have access to the entire paper) it identified an additional epitope that can cause the celiac reaction but it does not say that you can be celiac and have negative genetic testing to the genetic sequence showing predisposition to celiac disease.

Also, the fact that one of your children is negative for the genetic test and you are positive is also possible. My wife and I are both negative and two of our children are positive for genetic testing (and that triggered some discussions about paternity but at least one of them looks too much like me ).

"False" negative biopsies are actually happening all the time in particular in children because many celiac children are diagnosed by high tTG but the disease has not affected the intestines yet and therefore negative biopsies are not considered reliable anymore.

ravenwoodglass · March 18, 2020

On 3/17/2020 at 6:58 PM, docaz said:

I

Also, the fact that one of your children is negative for the genetic test and you are positive is also possible. My wife and I are both negative and two of our children are positive for genetic testing (and that triggered some discussions about paternity but at least one of them looks too much like me ).

Expand Quote

I think you misread info. I am firmly diagnosed. I was diagnosed before gene testing was being done. Thankfully because if gene tested before diagnosis I would have been told I wasn't celiac and would undoubtedly be dead by now. It wasn't until 5 years after both of my children were also diagnosed that one of them got gene tested and was told the blood and biopsy were wrong. We have a long way to go in the study of celiac and because of the experience in my family I hate to see people have the possibility dismissed if they happen to have one of the 'oddball' genes. Gene testing for only the two most common genes does not negate the possiblity that someone has celiac and should not be the first test done.