R. Crevel

For both wheat allergy and coeliac disease the dietary avoidance of wheat and other gluten-containing cereals is the only effective treatment. Estimation of the maximum tolerated amount of gluten for susceptible individuals would support effective management of their disease. Literature was reviewed to evaluate whether an upper limit for gluten content in food, which would be safe for sufferers from both diseases, could be identified. When setting gluten limits for coeliac disease sufferers, the overall potential daily intake should be considered, while for wheat allergy limits should be based on single servings. For coeliac disease sufferers this limit should lie between 10 and 100 mg daily intake. For wheat allergy, lowest eliciting doses for children lie in the lower milligram range, while for adults they are most significantly higher. Gliadins (part of the gluten proteins) not only trigger coeliac disease, but are also major allergens in wheat allergy. Therefore, measurement of gliadins with validated enzyme-linked immunosorbent assay methods provides an appropriate marker for assessing gluten and/or wheat protein contents in food. Available data suggest that a maximum gluten content for 'gluten-free' foods could be set, which protects both wheat allergy sufferers and coeliac patients.

To cite this article: Cochrane SA, Salt LJ, Wantling E, Rogers A, Coutts J, Ballmer‐Weber BK, Fritsche P, Fernández‐Rivas M, Reig I, Knulst A, Le T‐M, Asero R, Beyer K, Golding M, Crevel R, Clare Mills EN, Mackie AR. Development of a standardized low‐dose double‐blind placebo‐controlled challenge vehicle for the EuroPrevall Project. Allergy 2012; 67 : 107–113. Abstract Background: Double‐blind placebo‐controlled food challenge (DBPCFC) is the gold standard for diagnosing food allergy. Standardized materials and protocols are essential for comparing DBPCFC results for multicentre studies such as EuroPrevall. This required the development and piloting of a standardized vehicle and low‐dose protocol for confirming food allergy and determination of minimum eliciting doses (MEDs). Methods: A low‐dose DBPCFC protocol was developed, with eight titrated protein doses from 3 μg to 1 g. This was delivered using a simple, microbiologically stable food base incorporating allergenic food ingredients manufactured at three sites and centrally distributed to clinical centres. Allergen blinding was assessed by a professional sensory testing panel using a triangle test. Homogeneity and allergen content were confirmed by ELISA and clinical efficacy was assessed in a pilot study, using celeriac and hazelnut as exemplars. Results: Celeriac and hazelnut ingredients were sufficiently blinded in the dessert. The dessert meals were successfully piloted with hazelnut in allergy clinics in Spain, the Netherlands and Italy and with celeriac and hazelnut in Zurich. The challenges elicited a range of subjective and objective reactions ranging in severity from mild itching of the oral mucosa to bronchospasm. Conclusions: A standardized challenge vehicle proven to sufficiently blind processed, powdered hazelnut and celeriac ingredients and that can be reproducibly manufactured has been developed. This pilot study shows that the vehicle is promising for the confirmation of food allergy and determination of MEDs in adults and children with body weight >28.8 kg (approximately 7–11 years old).

Serious attempts to estimate the impact of allergic reactions to foods on public health did not begin until the 1980s. Until about 15 years ago, food allergy was considered a minor aspect of food safety. Two developments probably prompted a radical re-appraisal of that situation. The first was the apparently inexorable rise in the prevalence of atopic diseases, of which food allergy forms a part, with its possible consequences highlighted by some well publicized severe reactions. The second was the growth of genetic modification technology, manifested by the commercialization of transgenic crops. Each of these developments impacted on the food industry in distinct ways. On the one hand, food-allergic consumers had to be enabled to avoid specific allergens in products formulated with existing ingredients. Food manufacturers therefore had to identify those specific allergens down to trace amounts in all the ingredients forming the product, and label or remove them. On the other hand, the introduction of products using ingredients from novel sources required an assessment of the allergenicity of these ingredients as an integral part of safety assurance. The approaches used by the food industry to protect existing allergic consumers and those at potential risk of sensitization by novel proteins will be illustrated, emphasizing how they need to be built into every stage of the life cycle of a product.