Positive blood test but negative endoscopy

[Rianne]

About 1.5 years ago after months of different symptoms like stomach pain, gas, constipation/diarrhea, extreme fatigue, headaches, brain fog, joint pain etc I decided to go see my doctor. My blood tested positive for Anti tTG IgA (35 u/ml), not extreme high I guess. After this I had an endoscopy, where they took some biopsies, which came back negative for celiac. A false positive they called it. They told me to see a dietician, I tried the fodmap diet, lactose free, some enzyms, probiotica you name it. Nothing helped so they gave me the diagnosis of IBS and that was it.

Fast forward to now, 1 year later, I still live everyday in pain. I got my blood tested last week and again I still test positive for Anti tTG IgA. In addition, I have a small deficiency in Erythrocytes, Vitamine A, Vitamine D, Folic acid, Magnesium intracellulair and to the lower end levels of Hb and ferritine (but good Iron and Vitamine B12). With these results I am going back to my doctor but I am just tired of not knowing what is wrong with me.

So, I am just wondering if there are other people who also have positive blood test results but do not have celiac. And just here for some thoughts or advice on my situation.
 

 

[trents]

More than likely, either the damage to the villous lining of your small bowel was patchy and missed by the biopsy or you were in the very early stages of celiac disease such that little damage had been done to the villous lining. We suggest that at least four samples be taken from both the duodenum and the duodenum bulb to minimize the chance of missing damage due to patchiness. However, not all biopsies are done with this kind of thoroughness. 

[Rianne]

@trents Thank you for taking the time to respond! I am new here and already appreciate this forum. 

It also crossed my mind that maybe I was in the very early stages so little damage was done. My doctors just keep saying that I don’t have it. 

The report of my endoscopy said the following:
- 6 biopsies with growth to 0,3cm from the duodenum. No abnormalities, no villous atrophy, no intraepithelial lymphocytosis, no giardia lamblia and no morbus whipple

- 2 biopsies with growth to 0,2cm from the stomach antum. No abnormalities, no gastritis, no helicobacter pylori and no intestinal metaplasia

Last thing I would like to aks you. Do you know if there are people who have positive blood tests but do not have celiac. Is that even possible? Can something else cause my body to make these antibodies or does a positive blood test almost certainly mean I have celiac disease or get in the future. I would like to believe my doctors ofcourse, but I can also not find a single story anywhere where someone has positive blood results but not has celiac disease.

[trents]

Yes, there are a few medical conditions, some foods (i.e., the protein "casein" in dairy) and some medications (i.e., NSAIDs) that can cause positive blood tests without celiac disease in some people but they also cause damaged villi. So, that doesn't really fit either.

I still fall back on the early stage of celiac disease hypothesis, however. I think your next step would be to undertake a serious gluten free diet regimen for several months and see if your symptoms improve.

Edited May 10, 2024 by trents

[Scott Adams]

I agree with @trents. Unfortunately test results for celiac disease are not always definitive, and many errors can be made when doing an endoscopy for celiac disease, and they can happen in many ways, for example not collecting the samples in the right areas, not collecting enough samples, or not interpreting the results properly and giving a Marsh score. 

Many biopsy results can also be borderline, where there may be certain damage that could be associated with celiac disease, but it just doesn't quite reach the level necessary to make a formal diagnosis.

The same is true for blood test results. Over the last 10 years or so a new "Weak Positive" range has been created by many labs for antibody results, which can simply lead to confusion (some doctors apparently believe that this means the patient can decide if they want more testing or to go gluten-free). There is no "Weak Negative" category, for example. Many patients are not told to eat gluten daily, lots of it, for the 6-8 week period leading up to their blood test, nor asked whether or not they've been eating gluten. Some patients even report to their doctors that they've been gluten-free for weeks or months before their blood tests, yet their doctors incorrectly say nothing to them about how this can affect their test, and create false negative results.

Many people are not routinely given a total IGA blood test when doing a blood screening, which can lead to false negative interpretations if the patient has low IGA. We've seen on this forum many times that some doctors who are not fully up on how interpret the blood test results can tell patients that the don't need to follow a gluten-free diet or get more testing because only 1 of the 2 or 3 tests done in their panel is positive (wrong!), and the other 1 or 2 tests are negative. 

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.