Tissue transglutaminase Ab IgA test questions.

[wafflegirl]

Hi there, 

 I am currently awaiting gastroscopy and colonoscopy. I have had low ferritin for many many years. This summer I became extremely anemic so now need to dig into why. My doc first thought it was bleeding, negative stool test, made her suggest celiac. But she is still pretty convinced it is heavy bleeding ( I have not menstruated in 8 years, hysterectomy) I have no overt signs of gastric/colon bleeding. but taking oral iron is not increasing my ferritin. I have had 1  infusion and taking 100mg of heme iron daily and my ferritin did increase to 23 but I also had two units of blood. So I do suspect I am having issues absorbing nutrients. Just too many things add up to celiac for me. I am just impatient and wiating another two weeks for scopes and then longer for results is making me a bit crazy so I would appreciate any insights to the questions below.

5 years ago she did a h.pylori test and  Ab Iga test both were negative.

I have 2 questions:

1.It this single blood test: Transglutaminase Ab IgA test enough to rule out celiac?  The test notes state:  false negative results may occur with a gluten restricted diet or igA deficiency. The BioPlex method includes an internal conrol to confirm iGa is sufficient, thus avoiding false negatives. tested by a multi flow immunoassay bioplex method) 

2. Is it possible 5 years later to then test positive? 

I have two variants of celiac. HLA-DQA1 and HLA-DQB1 

 

[trents]

  On 9/28/2021 at 5:20 PM, wafflegirl said:

Hi there, 

 I am currently awaiting gastroscopy and colonoscopy. I have had low ferritin for many many years. This summer I became extremely anemic so now need to dig into why. My doc first thought it was bleeding, negative stool test, made her suggest celiac. But she is still pretty convinced it is heavy bleeding ( I have not menstruated in 8 years, hysterectomy) I have no overt signs of gastric/colon bleeding. but taking oral iron is not increasing my ferritin. I have had 1  infusion and taking 100mg of heme iron daily and my ferritin did increase to 23 but I also had two units of blood. So I do suspect I am having issues absorbing nutrients. Just too many things add up to celiac for me. I am just impatient and wiating another two weeks for scopes and then longer for results is making me a bit crazy so I would appreciate any insights to the questions below.

5 years ago she did a h.pylori test and  Ab Iga test both were negative.

I have 2 questions:

1.It this single blood test: Transglutaminase Ab IgA test enough to rule out celiac?  The test notes state:  false negative results may occur with a gluten restricted diet or igA deficiency. The BioPlex method includes an internal conrol to confirm iGa is sufficient, thus avoiding false negatives. tested by a multi flow immunoassay bioplex method) 

2. Is it possible 5 years later to then test positive? 

I have two variants of celiac. HLA-DQA1 and HLA-DQB1 

 

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1. If the tTG-IGA is positive then it almost certainly means you have celiac disease. If it is negative it does not rule out celiac disease. It is considered to be the most specific antibody test for celiac disease but not the most sensitive so sometimes it misses people who actually do have celiac disease. Here is a primer on various antibody tests that can be run to detect celiac disease: https://celiac.org/about-celiac-disease/screening-and-diagnosis/screening/ These will not necessarily be valid if someone has been eating gluten free or significantly reduced their gluten consumption weeks prior to the testing. Also, if total IGA is low it will skew test results toward the low side and can produce false negatives. 

2. Your second question makes no sense. Five years later than what? Having the genes for celiac disease does not guarantee that you have or will develop celiac disease. It only establishes potential. Actually developing celiac disease would require some triggering biological or psychological stress event such as a viral infection. You can develop celiac disease at any point in your life so negative testing at some point does not rule out getting the disease in the future. Many people who have the genetic potential for celiac disease never actually develop it.

[Scott Adams]

Given your genetic makeup, plus the positive tTG-IGA test, it's very likely you have celiac disease. Be sure to talk to your doctor before going gluten-free, as they may want to do an endoscopy/biopsy to verify this, and you would need to be eating gluten daily for two weeks before this.

[wafflegirl]

  On 9/28/2021 at 6:43 PM, trents said:

1. If the tTG-IGA is positive then it almost certainly means you have celiac disease. If it is negative it does not rule out celiac disease. It is considered to be the most specific antibody test for celiac disease but not the most sensitive so sometimes it misses people who actually do have celiac disease. Here is a primer on various antibody tests that can be run to detect celiac disease: https://celiac.org/about-celiac-disease/screening-and-diagnosis/screening/ These will not necessarily be valid if someone has been eating gluten free or significantly reduced their gluten consumption weeks prior to the testing. Also, if total IGA is low it will skew test results toward the low side and can produce false negatives. 

2. Your second question makes no sense. Five years later than what? Having the genes for celiac disease does not guarantee that you have or will develop celiac disease. It only establishes potential. Actually developing celiac disease would require some triggering biological or psychological stress event such as a viral infection. You can develop celiac disease at any point in your life so negative testing at some point does not rule out getting the disease in the future. Many people who have the genetic potential for celiac disease never actually develop it.

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Thank you, my doc refused to do the blood test again,says it was negative to forget that celiac was a possibility.  I’ve had extreme stress for the last 5 years escalating to large personal loss that’s been very stressful the last year, then topped off with extreme work stress the last 8 months. But it can’t be celiac she says.  Must be gastric bleeding 

[wafflegirl]

  On 9/28/2021 at 7:28 PM, Scott Adams said:

Given your genetic makeup, plus the positive tTG-IGA test, it's very likely you have celiac disease. Be sure to talk to your doctor before going gluten-free, as they may want to do an endoscopy/biopsy to verify this, and you would need to be eating gluten daily for two weeks before this.

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I didn’t have a positive ttg test, it was negative 5 years ago. I’m getting a scope in two weeks and of course not going gluten free yet.  I travel with a celiac coworker a lot and she had told me for three years she thinks I’m celiac. ( based on observing my food reactions and symptoms) but my negative ttg test made me think I couldn’t be. 

[trents]

wafflegirl, you need to get a new doctor.

[GodsGal]

Hi Wafflegirl!

I agree with @trents. You need to be seen by a different doctor. 

It is entirely possible to have either a false negative, or have something "turn on" your celiac genes in five years. I would suggest asking your coworker if they have a doctor that they would recommend. 

[wafflegirl]

  On 9/29/2021 at 5:21 AM, trents said:

wafflegirl, you need to get a new doctor.

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The gi doing my scope said he would look for celiac.  I’m not able to get a new gp.  I’ll know soon with the scope.  

  On 9/29/2021 at 10:57 AM, GodsGal said:

Hi Wafflegirl!

I agree with @trents. You need to be seen by a different doctor. 

It is entirely possible to have either a false negative, or have something "turn on" your celiac genes in five years. I would suggest asking your coworker if they have a doctor that they would recommend. 

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She lives on the east coast I’m on the west coast so it’s not possible. I’ll know soon as the gi doing the scope said he would look for celiac.  

[trents]

Have you recently been avoiding gluten? The scope many be invalid if so.

[Scott Adams]

  On 9/29/2021 at 2:47 AM, wafflegirl said:

I didn’t have a positive ttg test, it was negative 5 years ago. I’m getting a scope in two weeks and of course not going gluten free yet.  I travel with a celiac coworker a lot and she had told me for three years she thinks I’m celiac. ( based on observing my food reactions and symptoms) but my negative ttg test made me think I couldn’t be. 

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It's good that you're still eating gluten, they recommend two slices of wheat bread a day for two weeks before an endoscopy for celiac disease. 

Keep in mind that none of these tests would rule out non-celiac gluten sensitivity, for which there currently isn't a test, but ~12% of people have. You still may need to go gluten-free to get relief, it if is the source of your symptoms.

[wafflegirl]

  On 9/29/2021 at 3:19 PM, trents said:

Have you recently been avoiding gluten? The scope many be invalid if so.

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Nope, I am fully aware to continue eating gluten. 

[frieze]

  On 9/29/2021 at 7:40 PM, wafflegirl said:

Nope, I am fully aware to continue eating gluten. 

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?Kaiser?

  On 9/29/2021 at 1:57 PM, wafflegirl said:

The gi doing my scope said he would look for celiac.  I’m not able to get a new gp.  I’ll know soon with the scope.  

She lives on the east coast I’m on the west coast so it’s not possible. I’ll know soon as the gi doing the scope said he would look for celiac.  

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Why can you not change doc?

[trents]

  On 9/29/2021 at 1:57 PM, wafflegirl said:

The gi doing my scope said he would look for celiac.  I’m not able to get a new gp.  I’ll know soon with the scope.  

She lives on the east coast I’m on the west coast so it’s not possible. I’ll know soon as the gi doing the scope said he would look for celiac.  

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Make sure the doc doing the scope not only looks for celiac but actually takes biopsy samples and sends them to a lab for microscopic analysis. Depending on the experience of the one doing the scoping, the resolution of the scope being used, and the extent of the damage it may not be visible to the naked eye.

[wafflegirl]

  On 10/3/2021 at 7:56 AM, frieze said:

?Kaiser?

Why can you not change doc?

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I live in a small town where there is a doctor shortage.  Not enough doctors, vast majority of people here have no family gp