There are 3 main forms of gluten reactions:
- allergic (wheat allergy)
- autoimmune (celiac disease, dermatitis herpetiformis and gluten ataxia)
- possibly immune-mediated (gluten sensitivity)
It is now becoming clear that, besides those with celiac disease or wheat allergy, there are patients with gluten sensitivity in whom neither allergic nor autoimmune mechanisms can be identified. It has been estimated that, for every person with celiac disease, there should be at least six or seven people with non-celiac gluten sensitivity. Gluten sensitivity may therefore affect 6-10% of the general population.
Patients with gluten sensitivity have negative immuno-allergy tests to wheat and negative celiac disease serology; normal endoscopy and biopsy; clinical symptoms that can overlap with those of celiac disease, irritable bowel syndrome, and wheat allergy; and they show a resolution of symptoms when started on a gluten-free diet.
Currently there are no laboratory biomarkers specific for gluten sensitivity, and the diagnosis is based on exclusion criteria; elimination of gluten-containing foods from the diet followed by an open challenge is most often used to establish whether health improves with the elimination or reduction of gluten from the patient’s diet.
New nomenclature and classifications are proposed (see the figures below).
"Fibromyalgia of the gut"
Some physician have labeled "gluten sensitivity" "fibromyalgia of the gut" to reflect the presence of symptoms in the absence of pathological findings. The BMJ editor-in-chief reflected on these doubts in an editorial: Gluten sensitivity: real or not?.
Since there are no biomarkers, gluten sensitivity is the ultimate diagnosis of exclusion. The worldwide shift to the Mediterranean diet may explain the rising prevalence of gluten sensitivity. The has been an “explosion of requests” for serological testing for celiac disease since 2007.
3 million Americans are living with celiac disease
Celiac disease, an immune system reaction to gluten in the diet, is four times as common today as it was 50 years ago. Lack of awareness of celiac could be contributing to a delay of up to 11 years in diagnosis of adults in North America (http://goo.gl/sy778).
This is an informative and beautifully designed video by the University of Chicago Celiac Disease Center. It looks like an infographic made into video - have a look:
New classification is being proposed for gluten-related disorders: celiac disease; dermatitis herpetiformis; gluten ataxia; wheat allergy; gluten sensitivity. WSJ, 2012.
Recent studies support the existence of the new condition nonceliac gluten sensitivity which is defined as symptoms with negative celiac antibodies and biopsy (http://goo.gl/57IlB).
Non-coeliac gluten sensitivity | BMJ, 2012.
Gluten sensitivity: real or not? | BMJ http://buff.ly/ZgKgK1
Does gluten sensitivity in the absence of coeliac disease exist? | BMJ http://buff.ly/RvC7zg
New nomenclature and classification of gluten-related disorders - http://www.biomedcentral.com/1741-7015/10/13/figure/F1
Algorithm for the differential diagnosis of gluten-related disorders, including celiac disease, gluten sensitivity and wheat allergy - http://www.biomedcentral.com/1741-7015/10/13/figure/F4
Spectrum of gluten-related disorders: consensus on new nomenclature and classification. Anna Sapone et al. BMC Medicine 2012, 10:13 doi:10.1186/1741-7015-10-13.
Image source: Colon (anatomy), Wikipedia, public domain.
Disclaimer: I am an Assistant Professor of Medicine and Pediatrics at University of Chicago.