Equivocal lab results

[elm1214]

Hello,

My daughter was just seen by a GI doctor due to recurrent vomiting episodes, usually about every 4 weeks. The doctor tested for Celiac just to rule it out, but didn’t think that’s what it was. 

The doctor said her lab results came back “mildly elevated”. The lab reference says “equivocal” (see below). They are going to proceed with an EGD soon.

Just wondering if anyone else had similar “equivocal” lab results? Wondering how likely it is that she has celiac or if it’s still possible that she doesn’t have it. 

Thank you! 

TTG IGA

Your Value 9.2 U/mL

Standard Range<7.0 U/mL

INTERTRETIVE DATA:
<7=NEGATIVE
7-10 EQUIVOCAL
>10 POSITIVE

 

[trents]

Yes, an "equivocal" TTG-IGA can certainly leave the door open for a celiac disease diagnosis. In fact, I would say it is more likely than not. In fact, not infrequently we have people with negative TTG-IGA values who wind up getting diagnosed as having celiac disease because their symptoms still point that direction and are later confirmed to have celiac disease via endoscopy/biopsy of the small bowel.

Several things can cause negative or equivocal TTG-IGA values, including already having started on a gluten free diet and low total IGA. Did the report include a total IGA value? Also, although TTG-IGA is very specific for celiac disease it is not a very sensitive test. So, it will often miss those who actually have celiac disease. Read this very recent study: https://www.beyondceliac.org/research-news/can-you-trust-negative-blood-test/?utm_campaign=Research Opt-In&utm_medium=email&_hsmi=132215467&_hsenc=p2ANqtz-8fACYIDMKClWlskmmwrskRau68CS70ye3lEsf5WIzBO1inMYDXE2rfjqzrVG5cHRgP84ZiubnJmv0EVKkl2INW0EriwQ&utm_content=132215467&utm_source=hs_email

The study linked above suggests the importance of running a full celiac antibody panel instead of just the TTG-IGA: https://celiac.org/about-celiac-disease/screening-and-diagnosis/screening/ Unfortunately, there is a dearth of knowledge about celiac disease in the medical community at large and many primary care docs just aren't up on it; and even some GI docs are not well-informed either. Make sure the GI doc takes biopsies when the EGD is done.

 

[elm1214]

Thanks for your reply! Yes they did run a total IGA, that was normal and in the middle of the range. Those were the only 2 celiac labs they did, because I don’t think she was expecting them to show any problems. 

I will make sure to ask her doctor about performing biopsies during the EGD, which will hopefully be scheduled soon. 

[trents]

Celiac disease damages the "villi" that line the small bowel. Depending on the extent of the damage and the resolution of the scope, experience of the doc doing the scoping, etc. this damage may not be visible to the naked eye. That's the purpose of the biopsy which is then sent to a lab for microscopic analysis. An experienced GI doc will take at least four samples from various places in the small bowel since the damage can be spotty. The villous lining of the small bowel is the organ of nutrient absorption. When the villi are rounded off and flattened by constant inflammation from celiac disease, the efficiency of nutrient absorption is impaired.

Edited June 13, 2021 by trents

[trents]

There is also NCGS (Non Celiac Gluten Sensitivity) that causes many of the same symptoms as celiac disease and some of the same long term health risks but does not cause villi damage. There is currently no diagnostic test for NCGS but can be assumed if eliminating gluten from the diet brings relief.

By the way, your daughter needs to be eating gluten regularly up until the EGD to make sure healing of the villi doesn't obscure the presence of the disease. Many make the mistake of going gluten free before either the blood antibody test or the endoscopy/biopsy and many doctors neglect to tell their patients not to do this.

Edited June 13, 2021 by trents