Coeliac Flashcards
Wheat grain
Bran (roughage) - fibre, vitamin bs , trace minerals, phytochemicals
Endosperm- carbohydrates, protein
Germ- b vitamins, vit E, trace minerals, phytochemicals, unusual / unsaturated lipids
Prolamine
Gluten
Prolamin fraction is gliadin in wheat and the other fraction is gkutenin
Prolamin fraction differs in other grains
Barley: hordein
Rye: secalin
Oats: avenin
Corn: zein
Pathophysiology
All people with CD have either DQ-2 or DQ-8 HLA alleles
Absence of HLA DQ2 excludes CD
Blood test or buccal scrape for kids
Result doesn’t depend on gluten intake
Small bowel atrophy- villous atrophy (flattening)
- partial
- sub total
- total
- because the vili fill with inflammatory cytokines
Crypt hyperplasia and infiltration of lymphocytes into the epithelium
Marsh rating (0, 1, 11, 11A, 11B, 111C, 4). 111ABC can diagnose coeliac. Marsh 4- refractory, someone who is on gluten free diet for 2 years with no improvement
Mechanism of damage
Genetic predisposition (HLA, DQ2, or DQ8) to an immune response resulting in mucosal damage
Gluten consumed as protein Peptide resides resistant to hydrolysis Deamination of peptides HLA DQ2 binds these peptides to T cells Subsequent release of cytokines which cause mucosal injury- villous atrophy of CD
Serological blood tests - antibodies
tTG: anti tissue translutaminase (IgA)
DGP: Deamidated gliadin peptide (IgA and IgG)
Must do these together with total IgA as increased prevalence of IgA deficiency in CD- need to do this to detect for a false negative. Lack of IgA will not show up on tTg test for DGP and therefore may ask condition
Good sensitivity test just looking for IgG is not orthodox
Can be used to aid a diagnoses but should not be used on their own to make a diagnosis- still need gastroscopy. Approx 20% false negative
Can be used to screen at risk groups
Diagnosis coeliac disease
Small bowel endoscopy with biopsy on a gluten containing diet
Histology: characteristic changes on a small biopsy
Serology; positive blood test for coeliac antibodies
Genetic profile: presence of HLA DG2 or DQ8
+/- symptoms: bloating, excess wind etc
Confirmation of diagnosis- improvement in histology and serology on a strict gluten free diet
If patient already on gluten free diet, need to get genotype test, and if confirmed, need to commence eating 4 slice of bread equivalent
Symptoms
Abdominal bloating and distension Excessive wind and flatulence Loose stools or constipation Nausea Low iron Fatigue Nutritional deficiencies - iron, folate, zinc, VitD, b12
Gluten containing grains and their products
Wheat- flours, starch, cous cous Rye- rye flour, rye meal Barley- barley flakes, pearl barley, malt, malt flavouring, male extract, malt vinegar Oats- oatmeal, oat bran Cornflakes Ham Cappuccino Icecream flavouring Sauces, gravies and condiments Soy milk Yeast extract spreads Confectionary
Food label reading
Declares as gluten free- less than 3ppm
Be gluten free but no claim- check ingredients and processing
If ingredient is derived from a food that causes an adverse reaction eg wheat barley oats, must have its source declared eg thickener 422 (modified wheat starch)
If ingredient derived from gold that is nkt from allergen the source does not need to be declared eg thickener 422 (modified starch)
Compound ingredients must be declared when they comprise >5% kg total products
Use of processing aids must be declared eg wheat starch in honeycomb
Ingredients containing no detectable gluten
Some contain no gluten even though derived from wheat eg Glucose Glucose syrup Dextrose Caramel colour Safe for inclusion in gluten free diet
“Oses” are gluten free
Compound ingredients
Foods containing a range of ingredients that are used in another product
Foods containing ingredients can be source of gluten eg mayonnaise, baking powder, stock powders/ boosters, soy sauce, yoghurt, curry powder, sounmilk etc
In contributes to more than 5% of product, all the ingredients of the compound ingredient will be listed in brackets
If it contributes less than 5% the allergen will only be declared in brackets after the compound ingredient
Avoiding cross contamination
Toasters, sanwich press
Margarine/ butter and spreads
Commanders and strainers
Grills and barbecues
Crumbs on benches and cutting boards
Dips shares with wheat and gluten free biscuits
Hot chips cooked in same oil as gluten containing foods
Medications
No active ingredient contains gluten
Gluten may be present in excipients
Unlikely gluten is separate excipients, may be present naturally as a constituent of some excipient ingredients
Nutrition care plan
- treatment
Correction of micronutrient deficiencies
Screening for complications eg low bone mineral density- may be inflammatory response to impaired calcium abs. Consider lactose and or fructose malabsorption - nutritional adequacy of diet
Ensure adequate CHO intake
Assess calcium, iron, folate and B12
Encourage basic dietary guidelines once weight is stabilised and feel well
30g fibre- difficult to achieve, wholegrains, skin on fruit and veg, nuts and seeds, psyllium husk, chia seeds etc
