Isabel Skypala

EAACI food allergy and anaphylaxis guidelines: diagnosis and management of food allergy

Food allergy can result in considerable morbidity, impact negatively on quality of life, and prove costly in terms of medical care. These guidelines have been prepared by the European Academy of Allergy and Clinical Immunologys (EAACI) Guidelines for Food Allergy and Anaphylaxis Group, building on previous EAACI position papers on adverse reaction to foods and three recent systematic reviews on the epidemiology, diagnosis, and management of food allergy, and provide evidence‐based recommendations for the diagnosis and management of food allergy. While the primary audience is allergists, this document is relevant for all other healthcare professionals, including primary care physicians, and pediatric and adult specialists, dieticians, pharmacists and paramedics. Our current understanding of the manifestations of food allergy, the role of diagnostic tests, and the effective management of patients of all ages with food allergy is presented. The acute management of non‐life‐threatening reactions is covered in these guidelines, but for guidance on the emergency management of anaphylaxis, readers are referred to the related EAACI Anaphylaxis Guidelines.

Advice provided by Health Professionals regarding precautionary allergen labelling

To the Editor, Many countries (including in Europe) mandate the disclosure of specific food allergens as ingredients in pre-packed foods. Manufacturers frequently provide additional advice as to the potential for unintentional contamination during manufacture, in the form of voluntary precautionary allergen labelling (PAL). With the exception of Japan and Switzerland, existing legislation does not extend to the use of PAL. This has resulted in the widespread use of PAL and variability in wording employed (such as ‘may contain...’, ‘may contain traces of...’ or ‘made in a factory...’), causing confusion and anxiety to allergic individuals and their carers, and significantly compromising consumer choice (1, 2). However, there are no published data on the advice providedbyhealthprofessionals (HPs) to allergic consumerswith regard to PAL. Neither the European Academy of Allergy and Clinical Immunology nor American Academy of Allergy, Asthma & Immunology provides advice as to the interpretation of PAL, although both associations are involved in work to improve their utility. We developed a web-based survey using scenario-based risk analysis (consisting of eight case vignettes, Table S1 in the Online Repository) to assess factors that might affect the advice provided by HPs with regard to PAL. Pilots were performed with focus groups of medical professionals and dietitians. HPs subscribing to the e-mail lists of the Allergy Academy at King’s College London and Paediatric Allergy Interest Group of the British Society for Allergy and Clinical Immunology were invited to participate. We were advised by our local research ethics committee that approval was not required. Data were analysed using Prism 6 software (GraphPad Software Inc, La Jolla, CA, USA); chi-squared test was used to analyse responses, a p value of <0.05 was considered significant. Two hundred and thirty-nine HPs participated in the survey: 57% medical practitioners (62 paediatricians; 50 allergy specialists; 24 primary care physicians), 20% dietitians and 20% nursing staff. Seventy-three per cent had been qualified for 5+ yr. Thirty-eight per cent of HPs recommended complete avoidance of foods with PAL to nuts (but no nut listed in the ingredients) (Fig. 1), 22% advised no avoidance was necessary. The remainder recommended that avoidance was not required under specific circumstances, which included the absence of intercurrent infection; asthma being under control; and the food products in question not being confectionery, baked goods or foreign cuisine (Indian/Chinese/Thai/Middle Eastern foods being named specifically). Only 12 of 86 HPs mentioned availability of an epinephrine auto-injector and other rescue medication as being an important factor. Other factors are listed in Table 1. A number of HPs mentioned that avoidance was less important where the PAL was ‘made in factory where nuts are processed’ as opposed to a simpler ‘may contain nuts’ label. Factors resulting in more stringent advice included asthma (56% recommending complete avoidance, p = 0.0037); prior anaphylaxis to the allergen in question (79%, p = 0.002); and prior mild reaction to a tiny amount (71%, p < 0.0001) (Fig. 2). Stringent avoidance

The development of a standardised diet history tool to support the diagnosis of food allergy

The disparity between reported and diagnosed food allergy makes robust diagnosis imperative. The allergy-focussed history is an important starting point, but published literature on its efficacy is sparse. Using a structured approach to connect symptoms, suspected foods and dietary intake, a multi-disciplinary task force of the European Academy of Allergy and Clinical Immunology developed paediatric and adult diet history tools. Both tools are divided into stages using traffic light labelling (red, amber and green). The red stage requires the practitioner to gather relevant information on symptoms, atopic history, food triggers, foods eaten and nutritional issues. The amber stage facilitates interpretation of the responses to the red-stage questions, thus enabling the practitioner to prepare to move forward. The final green stage provides a summary template and test algorithm to support continuation down the diagnostic pathway. These tools will provide a standardised, practical approach to support food allergy diagnosis, ensuring that all relevant information is captured and interpreted in a robust manner. Future work is required to validate their use in diverse age groups, disease entities and in different countries, in order to account for differences in health care systems, food availability and dietary norms.

Dietary Therapy and Nutrition Management of Eosinophilic Esophagitis: A Work Group Report of the American Academy of Allergy, Asthma, and Immunology

Eosinophilic esophagitis (EoE) is a chronic/immune-antigen-mediated disease characterized clinically by symptoms related to esophageal dysfunction and histologically by eosinophil-predominant inflammation. Dietary elimination therapy has been shown to be an effective, drug-free prescription for the treatment of EoE. A range of different dietary elimination therapies have been used. Regardless of the elimination diet chosen, dietary therapy requires in-depth nutrition assessment and management. Elimination diets are not without risk and may impact nutritional status, eating pleasure, and overall quality of life. With adequate guidance, dietary therapy can be effective and nutritionally balanced, and the adverse impact on lifestyle can be minimized. This work group report addresses the potential challenges of implementing an elimination diet for the management of EoE and provides instructions and tools for physicians, dietitians, and other allied health professionals to help guide them in planning elimination diets for both children and adults.

Sensitivity to food additives, vaso-active amines and salicylates: a review of the evidence

Although there is considerable literature pertaining to IgE and non IgE-mediated food allergy, there is a paucity of information on non-immune mediated reactions to foods, other than metabolic disorders such as lactose intolerance. Food additives and naturally occurring ‘food chemicals’ have long been reported as having the potential to provoke symptoms in those who are more sensitive to their effects. Diets low in ‘food chemicals’ gained prominence in the 1970s and 1980s, and their popularity remains, although the evidence of their efficacy is very limited. This review focuses on the available evidence for the role and likely adverse effects of both added and natural ‘food chemicals’ including benzoate, sulphite, monosodium glutamate, vaso-active or biogenic amines and salicylate. Studies assessing the efficacy of the restriction of these substances in the diet have mainly been undertaken in adults, but the paper will also touch on the use of such diets in children. The difficulty of reviewing the available evidence is that few of the studies have been controlled and, for many, considerable time has elapsed since their publication. Meanwhile dietary patterns and habits have changed hugely in the interim, so the conclusions may not be relevant for our current dietary norms. The conclusion of the review is that there may be some benefit in the removal of an additive or a group of foods high in natural food chemicals from the diet for a limited period for certain individuals, providing the diagnostic pathway is followed and the foods are reintroduced back into the diet to assess for the efficacy of removal. However diets involving the removal of multiple additives and food chemicals have the very great potential to lead to nutritional deficiency especially in the paediatric population. Any dietary intervention, whether for the purposes of diagnosis or management of food allergy or food intolerance, should be adapted to the individual’s dietary habits and a suitably trained dietitian should ensure nutritional needs are met. Ultimately a healthy diet should be the aim for all patients presenting in the allergy clinic.

Maize allergy: what we have learned so far.

Maize (corn in the USA) is present in a wide range of foods such as breakfast cereals, corn snacks and tortilla chips, polenta, cornflour (widely used in soups and sauces) and a whole range of wheat-free foods. There are a number of unanswered questions regarding maize allergy. These include the mechanisms and symptoms involved, prevalence in adults and children, allergens involved and clinical cross-sensitization, usefulness of diagnostic tests and management of maize allergy. It is important to have accurate national data on the prevalence of food hypersensitivity in order to meet the needs of the allergic community, particularly as the prevalence of food allergies vary depending on the diet and exposure to food allergens. The most common foods to cause food hypersensitivity reactions are milk, egg, peanuts, tree nuts, fish and shellfish [1]. Geographical variance in the prevalence of self-reported food hypersensitivity and differences in the foods reported to cause hypersensitivity have been well documented [2–4]. Examples include fish allergy that is frequently seen in Spain [5] and peanut allergy that is common in the USA [6]. Cereals account for about 70% of the world’s protein intake and include wheat, spelt, barley, oats, rye, rice, corn, sorghum and millet. Despite this, the prevalence of allergic reactions to most cereals is less well documented. In terms of maize allergy, the prevalence is unknown, although it has been reported to cause severe reactions, particularly in areas where maize is commonly ingested, such as southern Europe and Mexico [7]. A few cases of maize allergy have been reported by Bock [8]. In the UK, a recent Isle of Wight birth cohort study diagnosed only one child in a cohort of 969 children with challengeconfirmed maize allergy [9]. Cereal allergens include mainly cereal a-amylase and protease inhibitors, cereal prolamins and non-specific lipid transfer proteins (nsLTP). Allergic reactions to maize are linked to an nsLTP [10]. The major allergen of maize, Zea m 14, is an LTP and maintains its structure after cooking at high temperatures [10]. Maize LTP is known to cross-react with the LTP found in other fruits and vegetables (e.g. peach, cherry, barley and rice), and is especially homologous to the peach nsLTP Pru p 3. Maize-allergic patients are therefore not the typical cereal-allergic patient who is seen in wheat allergy (i.e. cross-reactivity to barley and rye). In addition, the increase in the world population puts increasing pressure on agriculture to provide enough food for everyone. This had led to developments in agricultural biotechnology which aim to provide foods with a better quality, improved nutritional content and health attributes, resistance to spoilage, and could even lead to foods with reduced levels of allergenicity, such as insect-resistant corn with genetically modified proteins. The central issue with these developments is defining and characterizing the allergenic potential of the protein involved. Management of maize allergy, just as with other food allergies, ultimately depends on food avoidance. EU foodlabelling laws require that all food products containing wheat, oats, barley or rye declare these on the label, but there is no such requirement for corn at present. In the current issue of the journal, Scibilia et al. [11] looked at subjects with a history of maize allergy. These patients underwent double-blind, placebo-controlled food challenge (DBPCFC) in order to identify the spectrum of symptoms manifested during challenge, the lowest provocation dose during challenge, and to determine the performance characteristics of maize-skin prick test and specific-IgE tests. All study participants experienced symptoms of IgE-mediated food allergy, which was reflected in their Correspondence: Dr Carina Venter, School of Health Sciences and Social Work, University of Portsmouth, James Watson Building, 2 King Richard 1st Road, Portsmouth PO1 2FR, UK. E-mail: carina.venter@port. ac.uk Cite this as: C. Venter, I. Skypala and T. Dean, Clinical and Experimental Allergy, 2008 (38) 1844–1846. doi: 10.1111/j.1365-2222.2008.03123.x Clinical and Experimental Allergy, 38, 1844–1846

Silk contact anaphylaxis.

Silk, which is obtained from the cocoon of the silkworm, is a recognized cause of occupational asthma in silk-industry workers (1). Allergic rhinitis and asthma caused by silk have also been reported in children in China, in the absence of occupational exposure (2). However, allergy to silk in clothing is rare, as silk threads to be used for fabrics are subjected to several processes that remove allergenic proteins. Fibroin, the structural protein of silk, is considered to have a low allergenic potential.

Sesame allergy in adults: Investigation and outcomes of oral food challenges

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Positive food challenges despite negative specific IgE testing

Background Skin prick testing and serum food-specific IgE testing are the most commonly used diagnostic tests in evaluating IgE-mediated food reactions. However, the presence of negative tests can be falsely re-assuring such outcomes do not always exclude allergy. Food challenges are therefore indicated. Double-blind, placebo-controlled food challenge is the gold standard for diagnosis, but in many situations, open food challenges are a more practical alternative.

Nutritional Management of Patients With Pollen Food Syndrome: Is There a Need?

Purpose of reviewPollen food syndrome (PFS) is a highly prevalent condition causing mild oropharyngeal reactions to plant foods due to recognition by pollen-specific antibodies. It is most frequent in adults, but it can also occur in children. This review aims to establish the pitfalls of diagnosis and the nutritional consequences, and whether individuals with PFS require an individualised dietary and nutritional management strategy.Recent findingsThe diagnosis of PFS can be made through history alone but is greatly enhanced by undertaking component-resolved diagnostic (CRD) tests to individual allergens in birch pollen and relevant foods. Management of PFS requires dietary avoidance of trigger foods, but often, many foods have to be avoided, which can affect quality of life and nutritional intake. Not all symptoms are mild, especially if concentrated forms of allergen are taken, which may occur more frequently with the increased emphasis of the health benefits of fruits and vegetables. Oral food challenge (OFC) and, in the future, novel immunotherapy may minimise necessary avoidance.SummaryDue to the high homology of the allergens involved, multiple allergy tests can result in mass exclusion of antioxidant-rich fruits and vegetables, which are important nutritional contributors to the diet. Thus, those with PFS should receive individual dietary counselling to prevent deficiency diseases, especially expectant mothers, children and those who are avoiding multiple foods.