Gluten-related disorders Flashcards
Gluten-related disorders:
- The most commonly recognised gluten-related disorders are:
– Coeliac disease (auto-immune).
– Wheat allergy (allergic).
– Non-coeliac gluten sensitivity (innate immunity).
- Gluten is the main structural protein complex of wheat, rye and barley that is difficult for humans to digest and can lead to many symptoms within, and outside, the GIT.
- The immune-trigger protein fractions of gluten include gliadins and glutenins.
Wheat allergy:
- An IgE-mediated allergic response that can develop within minutes to hours of exposure to wheat (digestion or inhalation).
- More common in children and many outgrow condition by aged 16
Wheat allergy: Symptoms
Irritation or swelling of the mouth and throat, hives, itchy rash, nasal congestion, headache, nausea, vomiting, GORD, difficulty breathing, diarrhoea and anaphylaxis.
Wheat allergy: Diagnosis
Via a ‘skin prick’ test and managed by the strict avoidance of wheat.
- Those with severe wheat allergy may likely carry an adrenaline auto-injector (EpiPen) and wear an emergency card or bracelet with details of their allergy.
Coeliac disease (CD)
Coeliac disease (CD) = an autoimmune condition whereby the immune system can attack the mucosal lining of the small intestine in response to gluten, resulting in villous atrophy and malabsorption.
- Affects 1 in 133 (10–20% diagnosed).
CD: Symptoms
Abdominal pain, nausea, vomiting, diarrhoea, steatorrhoea, fatigue, anxiety, anaemia, weight loss, failure to thrive, osteoporosis, malnutrition, dermatitis herpetiformis and ataxia
CD: Complications
Malabsorption (e.g., B12, B9, iron, calcium), osteoporosis, anaemia (iron / megaloblastic)
CD: pathophysiology
- It involves an inappropriate adaptive immune response to gluten-derived peptides (i.e., gliadin).
- Gliadin is thought to be toxic to enterocytes in those with CD.
tTG
‒ It is modified (cross-linked) by tissue transglutaminase (tTG) to allow gliadin to be presented to the immune system.
- ‘Antigen presenting cells’ target gliadin and take up tTG-gliadin complexes producing autoantibodies and inflammation which damage the villi.
- Gluten upregulates zonulin — a peptide known to reversibly regulate intestinal permeability by disassembling intercellular tight junctions.
CD: Diagnosis
- Blood test for: IgA anti-tissue transglutaminase (tTG) antibodies (first choice). IgA anti-endomysial antibodies (EMAs).
- Blood or saliva test for human leukocyte antigen (HLA) gene: HLA-DQ2 or HLA-DQ8. Note: 30‒40% of the global population carry at least one copy of this genetic variant but only 1% develop coeliac disease.
- The gold standard for a CD diagnosis is a duodenal biopsy of the small intestine to detect villous atrophy.
- All tests (except HLA) requires a gluten-containing diet for > 6 weeks.
CD: Natural support
- Coeliacs must follow a completely gluten-free diet for life.
- Some grains and foods contain proteins similar to gluten (cross-reactive foods) that may also need to be avoided. Cyrex Labs provides an appropriate test: (Cyrex Array 4 — Gluten-associated cross-reactive foods and foods sensitivity panel).
- For optimum recovery, a gut-healing diet such as the specific carbohydrate diet (SCD) can also be used.
- Nutritional deficiencies may also need to be addressed.
- Consider the need for supporting the intestinal barrier (‘repair’)
Non-coeliac gluten sensitivity (NCGS)
Non-coeliac gluten sensitivity (NCGS) = the development of GI and extra-intestinal symptoms upon gluten ingestion in people not affected by coeliac disease or wheat allergy.
NCGS: Key symptoms
Intestinal:
Bloating
Abdominal pain
Diarrhoea
Nausea
GORD
Constipation
Extra-intestinal:
Tiredness
Headache
Anxiety
Brain fog
Joint pain
Depression
NCGS: Diagnosis
Diagnosis is by way of e
i.e., the resolution of symptoms when gluten is withdrawn and the relapse of symptoms with gluten exposure.
- Some NCGS individuals may be reacting to other non-gluten proteins in wheat that can be measured in the Cyrex Array 3 (Wheat / Gluten Proteome Reactivity and Autoimmunity)
