Labcorp Celiac Testing for Providers vs. On Demand for Patients

[SunshineFace]

Hey all! Several testing questions, thank you in advance... I haven't drawn these yet and hoping to get clarification here first before I go!

I've switched providers and new doc ordered something called "Celiac Disease Panel" blood-work. But in the meantime, I set up my new patient account w/Labcorp & noticed they have OnDemand testing, so I paid out of pocket for what they call Celiac Disease Antibody Panel (previous provider failed to test for all antibodies) which includes:

tTG-IgA
Total IgA
DGP-IgG
tTG-IgG

 

The Labcorp Celiac Disease Panel my provider ordered is test #165142 and includes:
tTG-IgA
EMA-IgA
Total IgA with reflex to
tTG-IgG

1. Am I paying for the same thing my provider ordered with different names? If so I'll cxl my On Demand order, and if not...
2. Would there be a reason to keep my personal OnDemand order open? My previous testing showed only these two results from Kaiser (and since they don't use same abbrev. I can't tell if they are also testing the same things) so just to confirm...
3. Kaiser failed to test for all antibody groups? From what I can tell, they only tested 2 things (IgA and tissue transglutaminase IgA) Is that accurate? Or is that two different ways of saying the same thing? Why is there even a 'normal' range of antibodies?

June 26 on gluten-free diet =  IgA 250 mg/dl  normal range is 40-350 mg/dl
                                       Tissue transglutaminase IgA value <1.9  normal value <=19.9

After starting gluten challenge on June 26 later that same day, I had immediate pain, inflammation, congestion, mood, cognition, and gut issues, etc... (after gluten-free diet for 6-9 months) and was able to get in with former doc two weeks later and she agreed to test antibodies again since I had such severe response to re-introducing gluten:

July 11 while eating gluten = IgA 268 mg/dl normal range is 40-350 mg/dl    (elevation in 2 weeks of gluten ingestion from 250-268 mg/dl) and no mention of 'tissue transglutaminase IgA'

 

Former doc also requested IgE Wheat Allergy test which came back negative and stool sample for Pancreatic Elastace(?) for diarrhea which came back normal. I also had endoscopy and Kaiser doc did ONE biopsy! Report came back as 'normal' (so they say no celiac). During first couple weeks of my gluten challenge, the burning itching painful rash on lower legs re-appeared so I called Kaiser Dermatology to ask about getting a skin biopsy ahead of the endoscopy procedure knowing celiac could be confirmed this way too. They denied my request since endoscopy was already scheduled. Multiple missed opportunities that I will post about separately.

4. How to interpret the data so far? And I would ask you all to consider it's impossible to put myself thru another gluten challenge currently (so that won't be an option), but if antibodies are present for months after ingestion, wouldn't it make sense to test for all the antibodies now? I am happy to order genetic testing and any other stool sample testing that might confirm antibodies. I already know gluten is the issue - I'm wanting to confirm 'which kind of issue' if that makes sense!

Personal History: I am 60, both my adult kids have gone gluten-free (son few yrs ago, daughter 10 yrs ago) No one in family endoscopy/biopsy confirmed (yet!). Only my one recent short window of 6-9 months eating gluten-free/grain free to reduce pre-diabetic status (which worked, btw), ate whole wheat, homemade bread starting in the 1970s and heavy wheat eater all my life 4-5x day. Made my own bread, worked in bakeries, and family history of several generations of wheat farmers. And I seriously doubt that 6-9 months of gluten-free eating will heal a lifetime of damaged villi, if I have celiac. What is more concerning to me is that I've been tracking Gluten Ataxia/Gluten Encephalopathy symptoms for the past 10 years...the diarrhea, anxiety and emotional overreactivity started in early grade school. I've also spent the past 5 years stuck in the mental health world with a bag full of medications that didn't work for mood, focus, attention, etc because they never addressed the root cause. And now I have 2 young autistic grandsons who exhibit some of the same symptoms, so I'm really at more of an activist mindset of understanding how did I get here and how can we work to make it better for future generations? I am so grateful for online communities where people can share stories and ask questions! Sorry so long, and thank you for reading and any insight or strategies are very much appreciated! ❤️

 

[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.

 

 

[RMJ]

3 hours ago, SunshineFace said:

Hey all! Several testing questions, thank you in advance... I haven't drawn these yet and hoping to get clarification here first before I go!

I've switched providers and new doc ordered something called "Celiac Disease Panel" blood-work. But in the meantime, I set up my new patient account w/Labcorp & noticed they have OnDemand testing, so I paid out of pocket for what they call Celiac Disease Antibody Panel (previous provider failed to test for all antibodies) which includes:

tTG-IgA
Total IgA
DGP-IgG
tTG-IgG

The Labcorp Celiac Disease Panel my provider ordered is test #165142 and includes:
tTG-IgA
EMA-IgA
Total IgA with reflex to
tTG-IgG

1. Am I paying for the same thing my provider ordered with different names? If so I'll cxl my On Demand order, and if not...
2. Would there be a reason to keep my personal OnDemand order open? My previous testing showed only these two results from Kaiser (and since they don't use same abbrev. I can't tell if they are also testing the same things) so just to confirm...
3. Kaiser failed to test for all antibody groups? From what I can tell, they only tested 2 things (IgA and tissue transglutaminase IgA) Is that accurate? Or is that two different ways of saying the same thing? Why is there even a 'normal' range of antibodies?

I just looked at Labcorp, they sure have a number of different celiac panels!

You’ve had the total IgA tested before so there isn’t much value in retesting that.  You don’t have a deficiency. 

The panel you ordered for yourself is missing one important test, DGP- IgA.  I would  get a panel that included that (along with tTG-IgA, tTG-IgG and DGP-IgG). If you can’t get a panel with both DGP tests I’d choose the one with the IgA over the IgG.

The panel the doctor ordered is quite incomplete.  It has no DGP antibody tests. EMA measures the same antibody as  tTG, just using a different method. It will only test for tTG IgG if your total IgA is low (that is the “reflex”). You already know your total IgA is fine so tTG IgG won’t be run.

Kaiser tested for total IgA, which measures IgA antibodies to everything, not just celiac.  They ran one specific celiac test, tissue transglutaminase (tTG) IgA.

Hope this helps!
 

 

[SunshineFace]

Yes, I was super excited to see all the Celiac Panels @RMJ, and then immediately overwhelmed because I have no idea what I'm ordering either! That helps a ton! And was exactly what I was looking for: a specific breakdown of which test(s) were done, which were ordered, and which ones can I order myself, so thank you for taking the time to spell it out! And clarifying the tissue transglutaminase (tTG) IgA is a specific celiac test, while total IgA is more of an 'everything' antibody test! And there's one more important test to order - DGP- IgA; perfect!

Makes sense from the article @Scott Adams left for me (Thank you Scott!) that the DGP tests are more critical since they target the gliadin peptides!

Celiac was only put on my radar a couple months ago and I'm doing my best to soak up all the knowledge here and other patient advocacy resources to stay a couple steps ahead of my docs which so far, don't seem to think this topic is relevant to them/or myself AT ALL, despite my growing list of symptoms. So thank you. 💖

 

[Scott Adams]

Here is more info about how to do a gluten challenge for a celiac disease blood panel, or for an endoscopy:

Quote

"...in order to properly diagnose celiac disease based on serology and duodenal histology, doctors need patients to be on gluten-containing diets, even if they are causing symptoms, and this is called a "gluten challenge."

• Eat gluten prior to celiac disease blood tests: The amount and length of time can vary, but is somewhere between 2 slices of wheat bread daily for 6-8 weeks and 1/2 slice of wheat bread or 1 wheat cracker for 12 weeks 12 weeks;
• Eat gluten prior to the endoscopic biopsy procedure: 2 slices of wheat bread daily for at least 2 weeks;

and this recent study recommends 4-6 slices of wheat bread per day:

 

 

[SunshineFace]

Thanks again @Scott Adams! I pick up something new every time I read over these articles.

I also wanted to share a link to Labcorp's current Celiac tests (as of Aug 2024); they have options for both patients with diets containing gluten and patients on a gluten-free diet!

(This page is from the 'Provider' tab, with test panel numbers/descriptions) This info could be very helpful in discussing with our own providers. There are Celiac panels, individual tests, genetic HLA DQ testing, and stool sample testing.

https://www.labcorp.com/endocrinology/disease-states/celiac-disease