Even though we’ve lived in our house for many years, some of our neighbors refer to our house as the ‘Walden’ house; the Waldens lived here for a long time before we did. Probably when we move, our neighbors will call our present home the “Hochman” house, regardless of who resides there.
I think nomenclature in medicine has a similar reluctance to adopt new terms. A recent medical progress report (Guandalini S, Polanco I. J Pediatr 2015; 166: 805-10) suggests dropping the term “Nonceliac gluten sensitivity” (NCGS) in favor of “Wheat Intolerance Syndrome.”
It’s probably a good idea and their arguments are sound. Two key points:
- “There is no proof that gluten is causing NCGS.”
- It is likely that the majority of patients considered NCGS have not even eliminated celiac disease before instituting a gluten-free diet.
With regard to the first point, the authors note that recent studies have suggested that a “FODMAP” (fermentable oligosaccharides, disaccharides, monosaccharides, and polyols) diet is likely the culprit in many cases of so-called NCGS. They review a pivotal double-blind study (see related blog post: An Unexpected Twist for “Gluten Sensitivity” | gutsandgrowth) there was no role for gluten “at least in these patients with IBS-like NCGS.” In addition, other studies have demonstrated a strong role for a placebo/nocebo effect of dietary elimination. “It is quite conceivable that a portion of patients with NCGS, and arguably a substantial one, fall in this category.”
With regard to the second point, it is not a good idea to initiate a gluten-free diet before excluding the diagnosis of celiac disease (hence the prior term: “nonceliac” gluten sensitivity). A related comment from the authors is that a “Grade 1 [Marsh] intestinal lesion has traditionally been considered of a very low specificity for celiac disease.” More testing in this circumstance can help determine if celiac disease is the reason, including checking the levels of ϒδ T-cell receptors in intraepithelial lymphocytes (very specific for celiac disease) and/or detection of IgA anti-tissue transglutaminase antibody deposits in intestinal mucosa.
Other pointers:
- Genetic testing for HLA-DQ2 and/or HLA-DQ8 genotypes (which are nearly 100% in celiac disease) are present in about 40% of NCGS which does not differ from the general population
- “Estimating the prevalence of NCGS is impossible.” Estimates have ranged from 0.6% of the U.S. population to as high as 50% according to some websites.
Bottomline: While “Wheat Intolerance Syndrome” works fine for me, I think the term nonceliac gluten sensitivity is going to be around for a while. Hopefully, more families and care providers will exclude celiac disease before contemplating this label and consider other foods as potential contributors to the symptomatology.
Related Reference: “Coeliac Disease and Noncoeliac Gluten Sensitivity” Meijer CR, Shamir R, Mearin ML. JPGN 2015; 60: 429-32. This reference covers much of the same territory. The Table 1 in this article nicely summarizes the relevant literature/studies from 2008-2014.
Related blog posts:
- How Likely is Celiac Disease if My TTG Test Is Only a Little Bit
- Closer followup for Celiac disease & pediatric guidelines …
- Gluten-Related Disorders” (Part 1) | gutsandgrowth Antibody tests “become negative in 15% after 1 month on GFD and in 57% after 3 months…diagnosis of CD cannot be made while on GFD.”
- Gluten-Related Disorders” (Part 2) | gutsandgrowth
- Food choices, FODMAPs, and gluten haters | gutsandgrowth
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