Confused by test results?

[Anellie8]

So a few months ago, I got a really bad case of food poisoning, and seemed to never recover.  I went to my GI, and she ran the standard blood tests, including celiac, which came back positive, and now I have a biopsy scheduled.  

I had been off gluten for ~10 days before my blood test, doing Whole30 in an effort to feel better, and so I don't know if that affected the results.  I was also under extreme stress during the time of my initial illness.  I was told my age, gender, and the stress makes me at a higher risk for an autoimmune disorder (mid 20s female).

Is it possible to have a false positive?  I have no family history.  If I've only been sick for a few months (since May), will my biopsy even show damage?

Results:

Deamidated Gliadin Abs, IgA: 8

Deamidated Gliadin Abs, IgG: 3

Negative 0-19

Weak positive 20-30

Positive >30

tTG IgA: 8

Negative: 0-3

Weak Positive: 4-10

Postive: >10

note: tTG has been identified as the endomysial antigen.  Studies have shown that endomysial IgA antibodies over a 99% specificity for gluten sensitive enteropathy.

tTG IgG: 11

Negative: 0-5

Weak positive: 6-9

Positive: >9

Endomysial Antibody IgA: Negative

Immuniglobin A, Qn, Serum: 163

87-352 (normal)

 

[trents]

Being off gluten for 10 days could have definitely skewed your test results toward the negative side. The only positive you have in that test battery is the tTG-IGG. The tTG-IGA is considered to be the best, most well-rounded test for celiac disease. Supposedly, it combines good sensitivity with good specificity. The other tests fall short in one or the other of those ways. 

False positives are much less likely than false negatives. The guideline for pre test gluten challenging for the blood tests is eating an amount of gluten equivalent to two slices of wheat bread for 6-8 weeks before the antibody tests and for 2 weeks leading up to the endoscopy/biopsy.

[Anellie8]

3 minutes ago, trents said:

Being off gluten for 10 days could have definitely skewed your test results toward the negative side. The only positive you have in that test battery is the tTG-IGG. The tTG-IGA is considered to be the best, most well-rounded test for celiac disease. Supposedly, it combines good sensitivity with good specificity. The other tests fall short in one or the other of those ways. 

False positives are much less likely than false negatives. The guideline for pre test gluten challenging for the blood tests is eating an amount of gluten equivalent to two slices of wheat bread for 6-8 weeks before the antibody tests and for 2 weeks leading up to the endoscopy/biopsy.

The tTG-IgA is a weak positive (8, with 10 being a full positive); are weak positives not positive?

[trents]

20 minutes ago, Anellie8 said:

The tTG-IgA is a weak positive (8, with 10 being a full positive); are weak positives not positive?

Weak positives, especially if you have been off gluten pre-test, would indicate celiac disease.

[Scott Adams]

It's interesting that your story is similar to mine with regard to a bad case of food poisoning triggering your celiac disease. I was backpacking in Europe one summer and ate something from a cheese shop that made be very ill within a few hours. I got very sick for a few days, and afterwards never fully recovered. That began a long ~6-7 year quest to finally get diagnosed.

At least in your case it looks like you won't have to go through years of suffering to figure this out, so you must have a pretty good doctor.

[Ginger38]

3 hours ago, trents said:

Weak positives, especially if you have been off gluten pre-test, would indicate celiac disease.

What if a person has been consuming gluten, maybe not the recommended amount daily, but still eating gluten, would a weak positive TTG-IGA still be an indication of celiac disease?

[trents]

Yes. The less gluten consumed, the less inflammation that is happening. The less inflammation that is happening, the lower the antibody levels will be.  Antibodies are involved with the inflammation chain of events. Antibodies are part of the immune system response to an invader (such as gluten for celiacs). Antibodies are marshalled to fight the invader and the result is inflammation.

[Anellie8]

If it helps someone later, at my follow-up, I found out my biopsy was negative, but my doctor said that with EMA being positive (and improvement I had had on the gluten-free diet after the biopsy), she was willing to diagnose me with early stage celiac disease (I think she called it latent celiac disease) since that can be hard to detect via biopsy, provided my genetic test comes back positive (which I am still waiting on).  Basically the tl;dr from her was that I can tell people I'm celiac, but on a technical level, that's not strictly true.  But it will be if I keep eating gluten, and I shouldn't harm myself just for it to be *official*

From what I've read on here, God was very gracious to me that I have a doctor who knows a lot about how celiac testing works, and how to take the biopsies, and even to check for it with a seemingly random set of symptoms.  

[Scott Adams]

I do believe this puts you in that grey area, and your doctor is correct here. You should avoid all gluten because this did help with your symptoms.