Celiac serology for child with long covid

[KR1]

Hi, my 12 year old has long covid and POTS and has had constant GI issues for more than 2 years. A new paed has run a whole suite of blood tests just trying to rule out other issues.  We won't see them again for a few months though and I'm just wondering if anyone can shed any insight into the coeliac serology she had done. 

Demidated gliaden peptide IgG    8 FLU (<5)

Total IgA     0.40g/L     (0.40-3.5)

Transglutaminse IgA     2 FLU (<5)

The only other red flag in her bloods was that her ferritin is 25 (20-150). This is just within range, but it was 22 last February and she's been on iron + vit c supplements ever since. I am so shocked at how little it has come up. 

We know the IGA is on the low side, it has been since she first got sick, and we've had varying interpretations of it from specialists (one paed said it meant nothing, another said it was possibly related to the constant GI issues and may be part of why she's SO sick so often). 

My first question is - I know low IgA can impact the Transglutaminse results. Is that likely the case here, or is hers still high enough that this is a trustworthy result?

I can see that demidated gliaden is slightly elevated. Does a low positive like this usually warrant further investigation or is this a common occurence even in non-coeliac patients?

And finally, I didn't realise they were testing for coeliac. My kiddo does not eat much gluten anyway - she's certainly not gluten free but we don't eat much pasta and she probably only has 1 piece of bread maybe 3 times a week. Should we have increased gluten intake before these tests for a trustworthy result? 

Thank you so much in advance for your replies and advice. Obviously we will await the paed's appointment for their expert take, I'm just wondering if this is likely to lead to further testing or if it's all low enough that we'll just ignore it. 

 

 

 

[trents]

Elevated DGP and IGG are often the only indicators of potential celiac disease we see when people are on a low gluten diet or have been tested weeks or months after commencing a gluten free diet.

But the wild card here may be the long COVID. One thing for sure is that I would put her on a high potency B-complex vitamin and a good amount of D3. Make sure all supplements are gluten-free.

[trents]

I note also that POTS can result from serious infections and is connected with autoimmune conditions such as celiac disease: https://my.clevelandclinic.org/health/diseases/16560-postural-orthostatic-tachycardia-syndrome-pots

Did the POTS precede COVID?

[KR1]

Thanks, she's not currently taking any B complex vitamins so I can certainly look into that. And definitely no POTS before covid. She had two infections 8 weeks apart in 2022 - hadn't recovered from the first when she suffered the second. She wasn't diagnosed with POTS until early 2023 but in hindsight those symptoms probably started with or around the time of covid #2. 

[trents]

To the B-complex I would add sublingual B12. You needn't worry about toxicity with B vitamin supplements because they are water soluble and any excess will be peed out. B12 is critical to proper iron absorption. And D3 is like a master vitamin in the body.

[Scott Adams]

This article might be helpful. It breaks down each type of test, and what a positive results means in terms of the probability that you might have celiac disease. One test that always needs to be done is the IgA Levels/Deficiency Test (often called "Total IGA") because some people are naturally IGA deficient, and if this is the case, then certain blood tests for celiac disease might be false-negative, and other types of tests need to be done to make an accurate diagnosis. The article includes the "Mayo Clinic Protocol," which is the best overall protocol for results to be ~98% accurate.