Do I Need To Eat Gluten For Accurate Blood Test?

[luciddream928]

I just saw a GI who scoffed at my Enterolab results. I'm fine with that since Enterolab pointed me in the right direction, and I understand that the GI wants to start from scratch.

My question is, do I need to be ingesting gluten in order to test accurately for celiac? I expressed my concern that I thought I had to be on a gluten diet so that I won't get a false negative on the test, and he said that "It's like the mumps, once you've got it, it will always show up."

However, 20 minutes before, I was talking to the physician's assistant who revised the chart after I asked her, "Hey wait, you ordered a celiac panel - does that mean I have to eat gluten for a few months?" She said, "Oh you're right, let's hold off on that."

So, it seems there's conflicting opinion. I've been gluten free for 5 months with a slip up (eating out or over others' houses) about every week or two. Not a sizeable amount of gluten, just traces. But I did have a LOT of symptoms at each slip up.

So I wonder if it matters? Any doctors in the house?

[Amyleigh0007]

I'm not a doctor, sorry, but I do have personal experience in that area. I did not eat gluten (or was very gluten light) for about 6 weeks prior to my blood tests. They came back negative. But, a gluten free diet makes a huge difference in my health so I was dx with gluten intolerance. Continue to eat gluten for testing to be accurate.

[sugarsue]

The tests my daughters got said on the lab results that the test assumes gluten is in the diet at the time of the test and out Pedi said don't cut out gluten until after the blood test.

Also, I've heard people posting here that you need quite a lot of gluten before the test, but I don't know what that limit really is (like how much and for how long).

[luciddream928]

Also, I've heard people posting here that you need quite a lot of gluten before the test, but I don't know what that limit really is (like how much and for how long).

Thanks for the replies! Yes I've heard that you have to eat gluten in order for the test to be accurate. I'm not sure why this doctor told me otherwise, but I figured if he's a GI then he should know... I've heard you have to eat about 4 slices of bread a day for at least three months (this would KILL my stomach).

What I'm afraid of is having a false negative and having them rule out celiac. I wondered during the appointment, could other autoimmune diagnosis like ulcerative colitis, Crohn's disease, and IBS actually be gluten intolerance in disguise? I think they talk about that in the Gluten Connection....

I also wonder.... they are doing a capsule study to look at my intestines. If I have been gluten-free for 5 months, then wouldn't it have healed even with slip-ups? Or are the slip-ups enough to still show damage to the intestine (if there is any)?

Not what I wanted... it seems the gluten-free diet screwed up my chances of getting an actual diagnosis : ( should've listened to my family of nurses!!!

[DingoGirl]

Thanks for the replies! Yes I've heard that you have to eat gluten in order for the test to be accurate. I'm not sure why this doctor told me otherwise, but I figured if he's a GI then he should know...

One would HOPE that a GI would know, but sadly, this is usually not the case.

and also, you DO have to be eating gluten regularly to get an accurate reading, this is true. The body responds to the invader, which for us, is gluten, by producing antibodies. I know that when I was tested, my tissue transglutaminase was greater than 100 (the measurement stops at 100, so who knows what the level really was) - normal is around 10 or less. (there are more scientific fact-remembering minds than mine on this forum! ) AT the six-month blood test, my ttg was down to 17.......quite a dramatic difference. My ferritin (stored iron) level was 2.5 - alarmingly low (normal is about 75 to 150 for a woman my size/age) - - at the six-month mark it was up to 30. All other numbers changed dramatically as well, and the endoscopy showed absolutely no villi at all.

If you really need the official diagnosis of Celiac, you will have to go back to eating gluten regularly. And also - - it doesn't sound like your doctor is informed on Celiac at all.....be prepared to do all of your own research.....

[luciddream928]

One would HOPE that a GI would know, but sadly, this is usually not the case.

and also, you DO have to be eating gluten regularly to get an accurate reading, this is true. The body responds to the invader, which for us, is gluten, by producing antibodies.

If you really need the official diagnosis of Celiac, you will have to go back to eating gluten regularly. And also - - it doesn't sound like your doctor is informed on Celiac at all.....be prepared to do all of your own research.....

Awww. I was hoping this would be EASY!! LOL ; )

I feel like it's a hard thing to ask a doctor if they are informed about this... of course they will say, "Yes!" because they are "supposed" to.

He said that the tests through Prometheus labs are accurate even without consuming gluten. I wonder if they are different kinds of blood tests? This is what they are testing -

Comp metabol. = ama panels

CBC c diff. = Hematology

Sed. rate = Hematology

TSH = Chemistry

Giardia Ag = Microbiology

Celiac ds. Screen (this was written under "Other Tests")

Also written - "dx = diarrhea, bloating, constipation, weight loss"

[happygirl]

"A gluten-free diet should not be started until all diagnostic tests are completed, as the withdrawal of gluten can change test results" from: Open Original Shared Link

"All diagnostic tests need to be performed while the patient is on a gluten-containing diet." from the NIH Consensus Statement on Celiac Open Original Shared Link

"Before being tested, one should continue to eat a regular diet that includes foods with gluten, such as breads and pastas. If a person stops eating foods with gluten before being tested, the results may be negative for celiac disease even if celiac disease is actually present." Open Original Shared Link

"A person seeking preliminary diagnosis of celiac disease must be consuming gluten. " Open Original Shared Link disease-diagnosis.php

"It is important to continue eating a normal, gluten-containing diet before being tested for celiac." Open Original Shared Link

These are all highly respected sites from highly respected groups/doctors. Please share this info.

[luciddream928]

"A gluten-free diet should not be started until all diagnostic tests are completed, as the withdrawal of gluten can change test results" from: Open Original Shared Link

"All diagnostic tests need to be performed while the patient is on a gluten-containing diet." from the NIH Consensus Statement on Celiac Open Original Shared Link

"Before being tested, one should continue to eat a regular diet that includes foods with gluten, such as breads and pastas. If a person stops eating foods with gluten before being tested, the results may be negative for celiac disease even if celiac disease is actually present." Open Original Shared Link

"A person seeking preliminary diagnosis of celiac disease must be consuming gluten. " Open Original Shared Link disease-diagnosis.php

"It is important to continue eating a normal, gluten-containing diet before being tested for celiac." Open Original Shared Link

These are all highly respected sites from highly respected groups/doctors. Please share this info.

Wow, thank you! I will pass them along to my doctor. I also checked out the Prometheus website, which is the lab that the GI group sends the blood work out to. It turns out that they do the genetic testing for the major autoimmune disorders - Crohn's, Celiac, IBS, IBD, and UC. I think I'll call them and ask them, then I know my doc will be more responsive, and perhaps order the genetic test too. I'm caught b/t a rock and a hard place, I want the dx for sure but I don't want eat gluten again for that amount of time. I know what 2 slices of bread will do to me for a week, I can't imagine 4 a day for 3 months would do

Thanks again!

[DingoGirl]

It's a GREAT idea to print some materials for your doctor Although, he may be arrogant about it and scoff. My dentist does this. Doesn't care at all, neither did the endodontist he sent me to - very dismissive and arrogant, and I have no enamel on my molars, but they refuse to see the connection.

BTW, Promethus can still do the genetic testing.....just not reflect accurately the celiac blood panels if you're not eating gluten. It is really not good to have to do that, eat all the gluten for the testing - many people agonize over this.

Let us know how things go!

[luciddream928]

It's a GREAT idea to print some materials for your doctor Although, he may be arrogant about it and scoff. My dentist does this. Doesn't care at all, neither did the endodontist he sent me to - very dismissive and arrogant, and I have no enamel on my molars, but they refuse to see the connection.

BTW, Promethus can still do the genetic testing.....just not reflect accurately the celiac blood panels if you're not eating gluten. It is really not good to have to do that, eat all the gluten for the testing - many people agonize over this.

Let us know how things go!

It seems so common to have to deal with that arrogance. Que lastima.

I wonder if my slips count as eating gluten. Probably not enough

I am considering finding a new doc, though I'm not sure I want to go the "gluten-eating" route again.

[nora-n]

i was accidentally gluten-free for many moonths before the tests, and only had gluten (cake) on two occasions, like a funeral , and christmas.

i knew from thyroid testing that antibodies hang around for several weeks, but the celiac tests havs such a high cutoff that the two slip-ups are bound to give negative test results.

My numbers were not 0, though.

Celiac blood tests are different from other antibody tests in that they are only supposed to be postitive when there is huge damage visible in the intestines.

But, the ttg IgG test might still be positive for up to a year.

You can get the other celiac blood tests done, and they might have a small number i the grey zone, like mine. Or, you might be lucky and a test might still be highish. But they cannot be used to rule out celiac. My doctor mistakenly thinks he ruled out celiac in me when I was accidentally gluten-free because I was eating low-carb and only eating bread I baked anyway for my celiac daughter, with two occasions of cake.....

Try the gene test.

[ravenwoodglass]

Your doctor may be depending on the gene tests to help diagnose you. A real mistake as the US does not recognize any celiac genes other than DQ2 or DQ8 in most cases. There are actually 7 more genes that are recognized in other countries. If you can I would find another GI who is more knowledgeable or is at least willing to learn. It sounds like this guy may be someone who would rather throw meds at you than diagnose, but of course I could be wrong about that.

[luciddream928]

Your doctor may be depending on the gene tests to help diagnose you. A real mistake as the US does not recognize any celiac genes other than DQ2 or DQ8 in most cases. There are actually 7 more genes that are recognized in other countries. If you can I would find another GI who is more knowledgeable or is at least willing to learn. It sounds like this guy may be someone who would rather throw meds at you than diagnose, but of course I could be wrong about that.

Yes I think you are right. Luckily I am working with a P.A. whom I really like. She read all of my enterolab results and my food/symptom journal from cover to cover. I was very impressed by this. I know that she follows his orders, but also listens. I have insurance for 4 more months before I finish my internship and move, so unfortunately I'm not really open to starting from scratch with doctors I called a lot of offices and they are, unfortunately, not accepting new patients at this time where I live. I'd have to drive an hour to find another.

I will take Nora's advice to get the gene test. I wonder if the other genes include DQ1? I'm a double according to Enterolab's results. And definitely get the total IGG test. I was scarfing down the gluten up until August.

[luciddream928]

I also wonder, why the antibody cutoff is so high? I had scores of antigliadin = 8, tissue transglutaminast = 6, and fecal fat of 291. I wonder what "normal" is? I know that the fecal fat should be around 150, but it seems logical that those other two numbers should be close to zero to be normal. Ehh what do I know!

[Tim-n-VA]

As the above posts have pointed out, the normal blood/biposy tests are checking for the body's reaction to gluten so you have to have been consuming it.

However, at least one of the posts implied that genetic testing is being done. My understanding is that you don't have to be consuming gluten for the genetic testing because it isn't looking for a reaction.