Coeliac disease: Correctly recognise wheat-associated diseases
In case of diet-related disorders like abdominal pain, flatulence or stuffed feeling, a quick hypothesis can be that the reason is a wheat incompatibility and the contained gluten.
Often, the persons concerned abstain from bread, noodles and pizza. Prior to going on such a diet it should be diagnostically clarified whether the symptoms are actually diet-related and to what extent the "wheat" is actually involved.
In addition to the serious clinical picture of coeliac disease more and more the wheat allergy or a wheat sensitivity come to the fore. Lectins which protect the plants against predators like for example wheat germ agglutinin (WGA) can induce disorders in the human body.
Our step-by-step approach in the case of wheat-related complaints:
Stage 1: Diagnosis of coeliac disease
- Anti-transglutaminase antibodies (IgA/IgG)
- Anti-gliadin antibodies (IgA/IgG)
- New: Genetic testing of the coeliac predisposition
Elucidation whether the gene for the autoimmune component is present.
Stage 2: Diagnosis of a wheat allergy
- Type I allergy (IgE)
- Type III allergy (IgG1-3)
Stage 3: Sensitivity against wheat lectin (independently from gluten)
- New: Wheat germ agglutinin antibodies (IgG)
Coeliac Disease Predisposition HLA-DQ2 / DQ8 Genetic Test
The determination of HLA-DQ2 / DQ8 is especially useful in
- Patients with inconclusive coeliac disease (especially in children)
- dubious small intestinal biopsy results
- Patients with familial coeliac disease history
- Patients on gluten-free diet with ambiguous diagnosis
Since 99% of all coeliac disease patients carry HLA-DQ2 or DQ8, the test can safely include or exclude coeliac disease.
Diagnosis of coeliac disease
Coeliac disease is an inherited intolerance to gluten-containing foods such as wheat, barley and rye. It leads to damage of the intestinal mucosa and to an intestinal resorption disorder. Clinical symptoms of celiac disease are dependent on the extent of mucous membrane damage in the small intestine.
In some patients, the disease manifests itself in childhood, already - mainly between the 9th and 18th month of life. In the adults the disease is much weaker, and often described as latent coeliac disease. Symptoms may be abdominal pain, recurrent diarrhea or flatulence.
Epidemiological studies showed, that weak forms of coeliac disease are increasing in the western hemisphere. They may be found in up to 1.5% of the adult population. Since the weak forms of coeliac disease may lead to deficiencies, a diagnostic evaluation is useful. Non-treated coeliac disease increases the risk of developing non-Hodgkin's lymphoma. Furthermore, the risk of colorectal cancer may increase.
If a coeliac disease is suspected, a faecal test is recommended. To confirm the result a blood test is mandatory.
Anti-gliadin >150 mU/g Stool
Anti-transglutaminase > 150 mU/g Stool
The prevalence of coeliac disease in recent years is probably not only due to gluten, but to amylase trypsin inhibitors (ATIs), which are associated with gluten-containing products. These proteins activate the innate immune system, which releases inflammatory substances. The diagnosis of wheat sensitivity is based on the exclusion of a wheat allergy and coeliac disease. A wheat sensitivity is verified if the symptoms improve with a wheat-free diet and if they deteriorate with provocation diet.
Anna Sapone et al. describe diagnosis algorithms for wheat sensitivity (diagram on page 9).