Mystery Continues....

[brit16]

Everyone has been so helpful here.... I figured I would come back and ask for any insight on our latest test results.

If you haven't read our story..... We have been trying to get to the cause of our now 19 month old's diarrhea and slowed growth. Had a positive ttg igG ( low positive), which led to a biopsy. Biopsy came back negative and at the same time he ran a ttg iga test which came back at a 1 - negative. So the GI seemed to feel like we could rule out celiac disease. Told us to "give it some time and see how he was doing in a month or two". I tried my hardest to just put it out of my mind - the diarrhea seemed to have gone away and I thought " maybe I'm making something out of nothing".

But then the diarrhea came back even worse (over 10 times a day for three days) and he was crying out in pain every time he needed to poop. The pain is what got me. I called back and told him I was very concerned - he called me in and ran lots of blood test and poop test looking for answers.

At my request he also ran a total serum iga. Yesterday I got a call from the dr himself saying " you were right his total iga is low - 19 and 24/25 is considered normal - call on Monday".

So now I am trying to wait for the rest of the results. And to hear what he thinks this result means. Anyone have any insight on what this could mean??? Is celiac still a good possibility or des this point us in another direction? Thanks for any insight!

[nvsmom]

Poor little guy.    Unfortunately doctors do that frequently. We are told to go home, eat gluten, and come back when you are sicker so they can have proof (via blood test or endoscopy) that we are sicke enough to go on the "restrictive and hard to follow" gluten-free diet.   It is just cruel...

 

A low serum IgA means that any IgA based celiac testing (tTG IgA, DGP IgA, EMA IgA) done will probably be a false negative because not enough IgA is made to register positive antibody levels. That fact that he had a positive tTG IgA when he is low in IgA is very significant! In over two years on this board I have only seen one or two other adults able to test positive on a IgA based celiac test while deficient in IgA - if he had normal IgA levels, his tTG IgA would have probably been sky high!

 

The ONLY tests that could be used to test for celiac disease for your son are:

tTG IgG

DGP IgG

EMA IgG (hard to find)

AGA IgG (not very reliable test)

 

Toddlers are harder to get an accurate result from because the disease is still in the early stages. False negative rates will be higher. I suspected celiac disease in some of my kids, and even though their tTG IgA was negative, I made them gluten-free anyways because I knew that it misses up to 25% of celiacs (including the ones with higher IgA levels).  My doctor said it was a coincidence that their symptoms improved within a few months of oing gluten-free.  

 

He could also have the endoscopic biopsy done, but that test missed up to 1 in 5 celiacs... not that great.

 

Plus, IgA deficiency is more common in celiacs than in the regular population - that says something too.

 

You can not rule out celiac disease yet.  I think celiac disease is a stronger possibility now that you know his IgA is low and he still managed to make a positive tTG IgA at one point.  I would advise to get all the IgG based celiac disease tests run, and maybe do the endoscopy. I would strongly suggest that he go gluten-free at the end of it all regardless of what the tests say. He could have false negative tests (not uncommon for a young age) or he could have non-celiac gluten intolerance (NCGI) which has the same symptoms as celiac disease but can't be detected with blood tests. Going gluten-free can not hurt, it could only possibly help.

 

You might want to test the rest of the family - that could offer more answers too.

 

Best wishes.

[brit16]

Poor little guy. Unfortunately doctors do that frequently. We are told to go home, eat gluten, and come back when you are sicker so they can have proof (via blood test or endoscopy) that we are sicke enough to go on the "restrictive and hard to follow" gluten-free diet. It is just cruel...

A low serum IgA means that any IgA based celiac testing (tTG IgA, DGP IgA, EMA IgA) done will probably be a false negative because not enough IgA is made to register positive antibody levels. That fact that he had a positive tTG IgA when he is low in IgA is very significant! In over two years on this board I have only seen one or two other adults able to test positive on a IgA based celiac test while deficient in IgA - if he had normal IgA levels, his tTG IgA would have probably been sky high!

The ONLY tests that could be used to test for celiac disease for your son are:

tTG IgG

DGP IgG

EMA IgG (hard to find)

AGA IgG (not very reliable test)

Toddlers are harder to get an accurate result from because the disease is still in the early stages. False negative rates will be higher. I suspected celiac disease in some of my kids, and even though their tTG IgA was negative, I made them gluten-free anyways because I knew that it misses up to 25% of celiacs (including the ones with higher IgA levels). My doctor said it was a coincidence that their symptoms improved within a few months of oing gluten-free.

He could also have the endoscopic biopsy done, but that test missed up to 1 in 5 celiacs... not that great.

Plus, IgA deficiency is more common in celiacs than in the regular population - that says something too.

You can not rule out celiac disease yet. I think celiac disease is a stronger possibility now that you know his IgA is low and he still managed to make a positive tTG IgA at one point. I would advise to get all the IgG based celiac disease tests run, and maybe do the endoscopy. I would strongly suggest that he go gluten-free at the end of it all regardless of what the tests say. He could have false negative tests (not uncommon for a young age) or he could have non-celiac gluten intolerance (NCGI) which has the same symptoms as celiac disease but can't be detected with blood tests. Going gluten-free can not hurt, it could only possibly help.

You might want to test the rest of the family - that could offer more answers too.

Best wishes.

Thank you nvsmom - you are so helpful. I don't know if I typed it incorrectly or maybe you just misread my post . He had a negative ttg igA and a positive ttg igG. The igG was only a weak positive (whatever that means). We also already did the biopsy which came back negative. Now we add this low total iga to the mix and I'm just not sure what it all means. Still waiting on the call from the dr today to tell me what he is thinking. Thanks again for your help"

[nvsmom]

Thank you nvsmom - you are so helpful. I don't know if I typed it incorrectly or maybe you just misread my post . He had a negative ttg igA and a positive ttg igG. The igG was only a weak positive (whatever that means). We also already did the biopsy which came back negative. Now we add this low total iga to the mix and I'm just not sure what it all means. Still waiting on the call from the dr today to tell me what he is thinking. Thanks again for your help"

OOPS!  I did read it wrong. Sorry about that!

 

Well, most of what I said would still stand.  He will test negative in all IgA based tests - they are useless to him. The tTG IgG is the test that matters... and it's positive.  

 

Think of it sort of like getting a weak positive pregnancy test. The test may be barely positive compared to another woman's who's period is equally late, but they are both just as pregnant and the proof will be there in 9 months.  Unfortunately in celiac testing, often the only way to get a strong positive is to make oneself sicker over a few months... it is a less than ideal situation for your son.

 

My advice would be the same: possibly test using the IgG based tests, maybe do the endoscopy, and then definitely do the gluten-free diet regardless of what the next test results are.  He already had a positive and that does mean something.

 

I'm guessing others around here would more or less agree with me.  Good luck. I hope he is well soon.

[brit16]

Thanks! I do plan on giving the diet a try at some point - just want to make sure we are done running any test first.

He already had the endoscopy done and it was negative....

The thing that confuses me is that the GI doesn't seem to take the positive on the ttg igG that serious.....says it could have just been an infection or something that caused it?

[nvsmom]

I know that that can be true of the tTG IgA but I do not know if that is also true for the tTG IgG. A weak positive tTG IgA can rarely (<5%) be caused by diabetes, thyroiditis, crohn's, colitis, chronic liver disease, diabetes, and a serious intestinal infection. Unlike the IgG immune system which affects the mucosal linings, the IgG part of the immune system is more systemic so I'm not sure how an infection will affect it.

 

This report discuses most testing (pages 8-12) but does not get into the tTG IgG details: Open Original Shared Link

 

This articles discuses the difficulties in diagnosing pediatric celiac patients: Open Original Shared Link

 

This report shows that the sensitivity of the tTG IgG (SN) is only about 40% so most celiacs would be missed using this test, but the specificity (likelihood of it being celiac disease - SP) is 95%. He  has a 5% chance of the positive test being caused by something else besides celiac disease... I'd say that chances are it's celiac disease.  

 

I hope the rest of the results are clear cut for you. Just remember that it is not unusual for a celiac to be positive in one test yet negative in another, including the biopsy - it's similar that way to how other autoimmune diseases test (like lupus which has multiple tests too).

 

Hopefully one day it will be easier.  Let us know how the other tests come out.