Which Gliadin Antibody Test Should I Trust?

[etbtbfs]

I've been gluten-free since June 2003. Recently (summer 2010) I had a Diagnos-Techs (DT) saliva test to check adrenal function. The test includes a gliadin antibody test by default. The gliadin antibody test came back at 42, where a result >15 is positive.

I realize a blood test for gliadin antibodies isn't very sensitive, but I did one anyway as the first check on DT's result. The result was <1.0, i.e. nothing in the blood.

I feel I need an answer as to whether the DT test is correct or not. I feel my suspicion of the DT test result is warranted because I have taken the DT saliva test three times before, which straddled the point (June 2003) at which I went gluten-free. The past results for Gliadin Ab were all less than half of the result in 2010:

2002 19

2004 15

2006 17

My first thought of a reliable way of checking the DT result, was Enterolab. I have had an Enterolab stool test before, and consider that to be a "gold standard". The problem is expense, of course: the "full" test is $249, and the "full" test plus gene tests is $339.

I'm hoping someone here will have opinions on these questions:

1) Are there good reasons to believe the Diagnos-Techs saliva test for gliadin antibodies is, or is not, accurate? Given that I am careful with my diet, is there any reason why my score could be 42 now, when all previous scores were less than half of 42?

2) Given this situation, is the Enterolab test the best reality check? Or is there another option which is less of a stress on the bank, but still highly accurate?

Thanks in advance for any advice.

[ravenwoodglass]

Are you having symptoms?

[Skylark]

1) Sometimes lab tests are just done wrong. That's why doctors always repeat tests that are high if a person is asymptomatic.

2) Enterolab has not provided any information on the accuracy of their tests, so you should assume they are comparably accurate to any other clinical diagnostic lab like DT. Since you have a nice series of salivary IgA tests, it would make more scientific sense to spend money verifying the DT result rather than shifting over to stool tests.

[etbtbfs]

Are you having symptoms?

Actually ... I don't know! I had silent celiac; I never had 'classic' celiac symptoms, even though gluten enteropathy was probably progressing slowly for most of my life. What finally took me out were the 'indirect' symptoms stemming from thyroid dropout (gluten-provoked Hashimoto's) and adrenal arrhythmia/HPA Axis dysfunction.

So, I can't depend on symptoms, and it's unlikely I have much gluten in my system anyway. I just want to make sure that I'm not getting enough hidden gluten to cause damage.

[etbtbfs]

I took this question to Ron Hoggan because of his experience. What Ron had to say:

In addition to responding to gluten/gliadin, the saliva tests will respond to other substances such as avenin from oats. In the past year, I had used clean oats (the varieties from Bob's Red Mill and Gifts of Nature, which are grown on dedicated fields) on a few occasions. There are a small number of avenin-sensitive individuals who must avoid oats. Apparently there are no simple tests specific for avenin sensitivity. E.g., Enterolab does not include that in their stool test. Therefore, since there is no good way to diagnose sensitivity to oats, Ron recommends that nobody who has been diagnosed with celiac, should use oats. Ever.

There is a chemical relationship between gluten and avenin: both are in the class of compounds known as prolamines. A short introduction to this may be found under "oat sensitivity" and related topics at en.wikipedia.org .

Ron also said that the saliva tests can respond to airborne substances that are inhaled into the sinus and mouth. I don't think that is likely to be the case here, however, a celiac who has a job in a business where gluten flours are present, should probably not use saliva testing, and maybe rethink their job choice.

If anyone knows that there is in fact a reliable oat sensitivity test other than duodenal biopsy, please post it here. Otherwise, I guess I'll abstain from oats. Sigh.