How Definitive Is The Blood Test?

[terpeng]

My 16 year old daughter was diagnosed with celiac disease last week after 3 years of unexplained seemingly random stomach pains with no other symptoms. She was given a blood test to check for celiac disease. The doctor didn't really give me any more info other than to go gluten free for the rest of her life. I suspect I have had it for years myself, undiagnosed, and am going in for a blood test today. Is it really necessary to have the biopsy? It seems invasive. If the blood test is definitive, I don't see the point in the biopsy. Could it be a false positive? What exactly does the blood test do? Just say, "yes, you have the gene for it", or actually say, "yes, you definitely have celiac disease"? Any advice?

[Brenna'sMom]

My dd's tTG was 275, well beyond the normal range of 0-15. With this information, we made the diagnosis of celiac, and skipped the biopsy. With such a truly positive blood result and clear improvement on the diet, our physician felt there was absolutely no need to do the endoscopy, especially considering she's only 4 years old. Others may feel a need for the positive biopsy, especially if the blood results were somewhat equivocal. We just didn't feel comfortable putting her through it given the test results.

[mushroom]

What exactly does the blood test do? Just say, "yes, you have the gene for it", or actually say, "yes, you definitely have celiac disease"? Any advice?

I think you are confusing the genetic test with the antibody test.

The genetic test just shows whether you have a gene that predisposes you to develop celiac disease -- it does not diagnose it.

The celiac panel is a test involving four or five different blood tests specifically testing for celiac disease. A positive on any one of these tests is considered to be diagnostic of celiac, although many doctors want to do the endoscopy with biopsy for confirmation of damage to the small intestine, which is the current definition of celiac disease. However, there are other forms of gluten sensitivity which do not test positive on the celiac panel, but nevertheless cause as much damage as (or maybe more than) celiac itself. Some people refer to these as false negatives (a rate of about 20-30%); false positives hardly ever happen.

[terpeng]

Ok, I got more info from my dr appt today. I asked for a copy of my DD test results and the endomysial antibody IgA was positive. The tTG was 55 (I was told normal range was 0-3). The immunoglobulin A, Qn Serum was 151 (normal is 61-348) so that one is normal. Those were the only 3 tests done in the panel. My dr is a different one from DD but in the same office. I will get my test results for myself back on thursday. The dr said that yes, my DD definitely has celiac disease, but that she is not as sensitive to gluten as those with higher numbers, and therefore won't have to be as careful about contamination. Does that sound right? This is all so new to me and I keep hearing differing opinions from people. How do I know who is right? I am going to attend a support group meeting tmw night and hopefully get more answers.

[T.H.]

My dr is a different one from DD but in the same office. I will get my test results for myself back on thursday. The dr said that yes, my DD definitely has celiac disease, but that she is not as sensitive to gluten as those with higher numbers, and therefore won't have to be as careful about contamination. Does that sound right?

I'm so sorry to say that the doctor you saw is completely and utterly ignorant about celiac disease. I will restrain myself from saying more out of a desire to avoid using curse words.

Low numbers do not mean that she is less sensitive. Honestly, doctors are only now realizing that a negative biopsy can still be celiac disease - they don't know enough to know WHAT low numbers mean. My daughter had higher numbers on some tests than I did, and lower numbers on others...what does that mean, if lower tests is less sensitive?

But, as an example...low numbers could mean she's only been reacting to gluten recently, or that she was reacting at low levels for a long time and is slowly increasing only recently, or that she's been reacting like crazy for a long time, and her vitamin levels are so low that her auto-immune system can hardly function any longer and can't even PRODUCE high levels of antibodies at this point (I have heard a doctor say that he believed this does happen, because he had patients who would test very low, but then he'd have them go gluten free, heal a bit, and then try a gluten challenge. Their numbers would be sky high the second time around).

So...yeah, he's clueless.

The celiac group sounds like a good idea. From what I've experienced, celiacs in the trenches, so to speak, are often more up to date on research and information about the disease than doctors are, unless the docs are celiac experts. And there ain't a lot of the latter around.

But considering that this doctor just advised you to do something that would seriously harm your daughter, I'd make sure never to see him again re: her health. Ever. You'll never be able to trust what he says.

[Roda]

My youngest son(6.5) was only one number over positive on the Iga ttg. We did not do a biopsy. He has a pretty wild reaction when he gets gluten. First he will complain his tummy hurts, then his behavior does a 360 deg, he fixates on things and gets constipated. It takes a good week or so for things to get back to normal. So to me the actual number certainly does not correlate to reactions!

[Bubba's Mom]

My blood test showed in the normal range. My endoscope showed severe damage. Blood tests don't show false positives, but they can show false negatives as decribed above. My advice would be to get the blood test. If that comes back positive, no reason to get the invasive procedure. It it comes back negative you may wise to get the scope so you know?

[concernedmamma]

My son had fairly low numbers (13 or 15, can't remember) and his biopsy was scored 3, on a scale of 1-4. The numbers DO NOT relate to damage or sensitivity. He is EXTREMELY sensitive as well.

Kim

[Skylark]

Ok, I got more info from my dr appt today. I asked for a copy of my DD test results and the endomysial antibody IgA was positive. The tTG was 55 (I was told normal range was 0-3). The immunoglobulin A, Qn Serum was 151 (normal is 61-348) so that one is normal. Those were the only 3 tests done in the panel. My dr is a different one from DD but in the same office. I will get my test results for myself back on thursday. The dr said that yes, my DD definitely has celiac disease, but that she is not as sensitive to gluten as those with higher numbers, and therefore won't have to be as careful about contamination. Does that sound right? This is all so new to me and I keep hearing differing opinions from people. How do I know who is right? I am going to attend a support group meeting tmw night and hopefully get more answers.

Endomysial IgA is completely specific for celiac disease, and the positive TTG confirms that it wasn't an incorrect result. There are medical articles saying that people with positive endomysial don't need the biopsy to confirm celiac. The advantage to getting one is that you know her baseline.

TTG numbers are not at all correlated with celiac disease severity or the degree of gluten sensitivity. Your and your DD need to work together to figure out how sensitive she is, and it may change from year to year. The safest thing is to assume she is pretty sensitive and work from there.

[mom2m2j]

So happy to find these posts, my DD is asymptomatic but was recently tested due to having Down Syndrome. The blood tests came back positive, but I had been struggling with accepting the results. We have been referred to a pediactric GI by our pediatrician, but I do not want to put her through the biopsy. I don't have the results, but plan on getting them. Thanks for the info.