Updated: Jan 13, 2020
#1 Gluten reactions can be organized into 3 main categories: allergy to wheat, gluten sensitivity, and auto immune (i.e. celiac disease, gluten ataxia).
#2 Celiac Disease is associated with intestinal damage whereas gluten sensitivity can have adverse reactions to gluten but not have increased tTG autoantibodies or other inflammatory markers.
#3 In February 2011, 15 experts came to London to form a panel; they came to an agreement on various classifications and definitions of gluten intolerances. Primarily these are wheat allergy, celiac disease, gluten ataxia, and gluten sensitivity.
#4 Wheat Allergy – wheat proteins cause an immunologic reaction, specifically, an increase in IgE antibodies. Diagnosis includes a skin prick test (test must contain specific g epitope to react), oral food challenge, and IgE assay which has 75% specificity. With wheat allergy, no association with IgG has been found.
Classifications of wheat allergy:
Classic Wheat Allergy – affecting skin, gastrointestinal or respiratory tract
WDEIA – Wheat-Dependent Exercise-Induced Anaphylaxis; characterized by general urticaria (rash or hives) or can be as advanced as anaphylaxis
Occupational Asthma aka Baker’s Asthma – rhinitis (inflammation of the sinuses, stuffed nose)
Contact Urticaria (rash or hives of the skin)
#5 Celiac disease is a spectrum autoimmune disorder.
Digestive symptoms include changes in intestinal permeability (i.e. leaky gut) caused by gluten. Symptoms include vomiting, abdominal pain, and diarrhea.
Extraintestinal symptoms (symptoms other than digestive issues) include anemia, osteoporosis, and neurological disturbances.
Associated with celiac disease are IgA deficiency, diabetes type I, thyroiditis, Down syndrome, Turner syndrome, Hashimoto's, arthritis, and William syndrome.
#6 Diagnosing Celiac disease includes increases in IgA anti-tTG (initial test) and IgA anti-EMA (confirmation test). People who are positive for these biomarkers tend to have the enteropathy Celiac disease (digestive issues). For the IgA deficient and children <3 yrs, IgG is a recommended lab value to test.
Intestinal biopsy will show an increased number of intraepithelial lymphocytes (IELs) (>25 lymphocytes per 100 enterocytes), elongation of crypts, partial or total villous atrophy, decreased villous:crypt ratio.
Genetic testing involves a polymerase chain reaction sequence-specific oligonucleotide typing. Two genes associated with celiac disease are HLA-DQ2 and HLA-DQ8. For people who are negative for both of these genes will likely not have Celiac disease.
#7 The four out of five rule for diagnosing Celiac disease:
1. Typical symptoms of Celiac disease
2. Increased serum IgA biomarkers
3. Presence of HLA-DQ2 and/or HLA-DQ8
4. Small intestine biopsy - celiac enteropathy found
5. Response to gluten-free diet
#8 Celiac disease dermatitis herpetiformis aka skin Celiac disease is a cutaneous manifestation of immune response to gluten where a blistering, reddened rash forms. IgA deposits can be found in skin biopsy and thus intestinal biopsy is unrequired to diagnose.
#9 Gluten ataxia (aka idiopathic sporadic ataxia) can be found in the gluten sensitive or diagnosed Celiac disease. Ataxia is a result of damage to the cerebellum of the brain caused by immune response to gluten.
Biomarkers will show an increase in anti-gliadin antibodies. Twenty three percent of people with sporadic ataxia will have an increase in these biomarkers. IgG increase is more likely than IgA in this patient population. Sapone et al (2012) states that a gluten-free diet helps improve gluten ataxia and maintaining this diet for 6-12 months is necessary before antibodies normalize.
#10 Gluten sensitive people do not have an apparent increase in IgA anti-tTG or other antibodies. In terms of signs and symptoms, gluten sensitivity cannot be distinguished from Celiac disease. Gluten sensitivity is diagnosed by ruling out wheat allergy and celiac disease via diagnostic tests. Other signs and symptoms that may manifest are behavioral changes, bone pain, joint pain, foggy mind, diarrhea, eczema, headache, anemia, numbness of legs, arms, fingers, and abdominal pain.
(Sapone, et al, 2012)
Sapone et al. (2012). Spectrum of gluten-related disorders: consensus on new nomenclature
and classification. BMC Medicine, 10(13), 1741-7015.