New research casts doubt on the usefulness of TTG-IGA to diagnose Celiac Disease

[trents]

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

This study concluded that the TTG-IGA antibody test, which has become the "go to" for most physicians in diagnosing celiac disease is not nearly as reliable as has been thought. The above linked study seems to demonstrate that it misses a high proportion of those who actually do have celiac disease as confirmed by a follow-up endoscopy/biopsy of the small bowel lining. 

The problem seems to be that the TTG-IGA test, though very specific for celiac disease, is a much less sensitive than was previously thought. This throws weight back onto the endosocpy/biopsy as the gold standard for diagnosis. As the study points out, many physicians assume the TTG-IGA is very definitive and when it gives a negative they stop pursuing a celiac diagnosis, even though symptoms suggest celiac disease. This revelation came from comparing rates of negative celiac diagnosis when a follow-up endoscopy/biopsy was not done with those where a follow-up endoscopy/biopsy was done. To me, it also suggests the value of doing a complete celiac antibody panel rather than testing for TTG-IGA alone.

Edited June 9, 2021 by trents
typo

[Scott Adams]

We summarized this research as well, and it certainly means that better tests need to be developed: