Public perception of food allergy

How do health professionals translate evidence on early childhood allergy prevention into health literacy-responsive practice? A protocol for a mixed-method study on the views of German health professionals

INTRODUCTION

Paediatricians, general practitioners (GPs) and midwives in primary care are important sources of information for parents on early childhood allergy prevention (ECAP). Research has shown that preventive counselling by health professionals can be effective in improving patients' health literacy (HL) and health behaviour. Providing effective advice relies on two factors. First, health professionals need be up-to-date with research evidence on ECAP, to consider popular misconceptions and fears and to translate this knowledge into clear recommendations for parents (knowledge translation). Second, they need to know and apply counselling techniques and create a practice setting which accommodates parental HL needs (health literacy-responsive care). The objective of this study is to explore and assess how German health professionals take up and translate ECAP evidence into appropriate recommendations for parents, how they consider HL in counselling and practice organisation and what barriers and enablers they find in their performance of HL-responsive ECAP.

METHODS AND ANALYSIS

The study has a sequential mixed-method design, in two phases. In the first phase, qualitative semi-structured expert interviews will be conducted with health professionals (paediatricians, GPs and midwives) at primary care level and professional policy level. Data collection is ongoing until January 2022. In the second phase, based on the qualitative results, a standardised questionnaire will be developed, and pilot-tested in a wider population of German health professionals. The findings of both phases will be integrated.

ETHICS AND DISSEMINATION

The study has received ethical approval from the Ethics Committee of the University of Regensburg (18-1205-101). The results will be published in international peer-reviewed open access journals and via presentations at scientific conferences. The results will also be shared with German health professionals, decision-makers and potential funders of interventions.

Mechanisms of Wheat Allergenicity in Mice: Comparison of Adjuvant-Free vs. Alum-Adjuvant Models

Wheat protein is considered a major type of food allergen in many countries including the USA. The mechanisms of allergenicity of wheat proteins are not well understood at present. Both adjuvant-based and adjuvant-free mouse models are reported for this food allergy. However, it is unclear whether the mechanisms underlying wheat allergenicity in these two types of models are similar or different. Therefore, we compared the molecular mechanisms in a novel adjuvant-free (AF) model vs. a conventional alum-adjuvant (AA) model of wheat allergy using salt-soluble wheat protein (SSWP). In the AF model, Balb/cJ mice were sensitized with SSWP via skin exposure. In the AA model, mice were sensitized by an intraperitoneal injection of SSWP with alum. In both models, allergic reactions were elicited using an identical protocol. Robust IgE as well as mucosal mast cell protein-1 responses were elicited similarly in both models. However, an analysis of the spleen immune markers identified strikingly different molecular activation patterns in these two models. Furthermore, a number of immune markers associated with intrinsic allergenicity were also identified in both models. Since the AF model uses skin exposure without an adjuvant, the mechanisms in the AF model may more closely simulate the human wheat allergenicity mechanisms from skin exposure in occupational settings such as in the baking industry.

Advances in Molecular Mechanisms of Wheat Allergenicity in Animal Models: A Comprehensive Review

The prevalence of wheat allergy has reached significant levels in many countries. Therefore, wheat is a major global food safety and public health issue. Animal models serve as critical tools to advance the understanding of the mechanisms of wheat allergenicity to develop preventive and control methods. A comprehensive review on the molecular mechanisms of wheat allergenicity using animal models is unavailable at present. There were two major objectives of this study: To identify the lessons that animal models have taught us regarding the molecular mechanisms of wheat allergenicity and to identify the strengths, challenges, and future prospects of animal models in basic and applied wheat allergy research. Using the PubMed and Google Scholar databases, we retrieved and critically analyzed the relevant articles and excluded celiac disease and non-celiac gluten sensitivity. Our analysis shows that animal models can provide insight into the IgE epitope structure of wheat allergens, effects of detergents and other chemicals on wheat allergenicity, and the role of genetics, microbiome, and food processing in wheat allergy. Although animal models have inherent limitations, they are critical to advance knowledge on the molecular mechanisms of wheat allergenicity. They can also serve as highly useful pre-clinical testing tools to develop safer genetically modified wheat, hypoallergenic wheat products, novel pharmaceuticals, and vaccines.

Allergies and Childhood Acute Lymphoblastic Leukemia: A Case-Control Study and Meta-analysis

Background: Allergic disease is suspected to play a role in the development of childhood acute lymphoblastic leukemia (ALL). Studies conducted over the last several decades have yielded mixed results.Methods: We examined the association between allergy, a common immune-mediated disorder, and ALL in the California Childhood Leukemia Study (CCLS), a case-control study of 977 children diagnosed with ALL and 1,037 matched controls (1995-2015). History of allergies in the first year of life was obtained from interviews, mainly reported by mothers. Logistic regression analyses were conducted to estimate ORs and 95% confidence intervals (CIs), controlling for birth order, daycare attendance, and mode of delivery. In addition, we conducted meta-analyses with data from the CCLS and 12 published studies and employed a new method to estimate between-study heterogeneity (R_b).Results: Overall, no associations were observed between childhood ALL risk and specific allergy phenotypes or any allergy, as a group. However, having any allergy was associated with an increased risk of ALL among the youngest study participants. In the meta-analysis random-effects models, reduced odds of ALL were associated with hay fever (metaOR = 0.65; 95% CI, 0.47-0.90); however, restricting the analysis to studies that used medical records for assessment of allergy or recently published studies led to null or attenuated results.Conclusions: Overall, our findings do not support a clear association between allergy and childhood ALL.Impact: The degree to which epidemiologic studies can inform the relationship between allergies and risk of childhood ALL is limited by R_b. Cancer Epidemiol Biomarkers Prev; 27(10); 1142-50. ©2018 AACR.

Grass-Allergic Children Frequently Show Asymptomatic Low-Level IgE Co-Sensitization and Cross-Reactivity to Wheat

BACKGROUND

Specific immunoglobulin E (IgE) sensitization to wheat is more common than a doctor's confirmed wheat allergy and is also frequently observed in grass pollen-allergic patients (pollinosis patients). Thus, the objective of this study was to investigate the level and feature of serological IgE cross-reactivity between grass pollen and wheat in a cohort of pollinosis subjects with no diagnosis of wheat allergy.

METHODS

Seventy-two children, aged 5-17 years, with a doctor's diagnosis of pollinosis, IgE towards grass pollen, and currently eating wheat were recruited. Serum samples were analyzed for IgE against wheat, timothy grass/wheat-specific allergen components, Pru p 3, and cross-reactive carbohydrate determinants (CCD) and specific IgE-binding inhibition experiments were performed.

RESULTS

Sixty percent of the grass pollen subjects were sensitized to wheat with a median of 0.5 kUA/L. Wheat-sensitized subjects were more often sensitized to the two allergens, Phl p 12 and CCD, known to be cross-reactive between grass and wheat. Sensitizations to seven wheat-specific allergens derived from the gluten fraction were, with the exception of one individual, only found in wheat-sensitized subjects. These subjects also more often reported current and past history of allergy to staple foods (milk, egg, wheat, soy, and fish).

CONCLUSION

Wheat sensitization caused by cross-reactivity but also by sensitization to wheat-specific allergens was common in the grass-allergic children and also associated with allergy to staple foods other than wheat. The results indicate the presence of a subgroup of pollinosis patients with simultaneous sensitization to wheat and food allergy not only caused by cross-reactions.

Food avoidance and restriction in adults: a cross-sectional pilot study comparing patients from an immunology clinic to a general practice

BACKGROUND

With the introduction of avoidant/restrictive food intake disorder (ARFID) in the Diagnostic and Statistical Manual - fifth edition, there is an increased need to understand the prevalence and pattern of food avoidance and restriction in adults. High rates of food allergy and intolerance in immunology clinic populations, and subsequent high rates of elimination diets, place these individuals at a greater risk of developing pathological eating behaviours. This descriptive cross sectional pilot study aims to provide preliminary data on the prevalence and nature of food avoidance and restriction in an adult population, and to explore the reasons for this behaviour.

METHOD

A self-administered questionnaire was designed and distributed to adults presenting to an immunology clinic and a general practice over the course of 6 months to describe the prevalence and nature of avoidant and restrictive eating behaviours in this population. Pearson's chi square test was used to examine the strength of a potential link to a formal diagnosis of avoidant restrictive food intake disorder in these patients.

RESULTS

A total of 102 completed questionnaires were used for data analysis. Food avoidance or restriction was detected in 81 respondents (79%), with rates not significantly higher in the immunology clinic group compared to the general practice group (p = .242). Food allergy and intolerance were the most common reasons for disturbed eating patterns. Life impact secondary to food avoidance and restriction was reported by 26% of respondents, with significantly higher rates observed in the immunology clinic cohort compared to the general practice (p = .011).

CONCLUSIONS

Eating disturbances similar to those characteristic of ARFID are very common in adults. Food avoidance and restriction due to perceived food allergy and intolerance are significant reasons for such disordered eating patterns, particularly in an immunology clinic population. Further investigation is needed to determine if such eating behaviours are pathological and whether they qualify for a diagnosis of ARFID.

Perceived food hypersensitivity relates to poor asthma control and quality of life in young non-atopic asthmatics

Background

The relationship between perceived food hypersensitivity in asthmatics, food allergen sensitization, asthma control and asthma-related quality of life has not been studied.

Objective

Our aim was to study the prevalence of perceived food hypersensitivity in a cohort of young asthmatics, its relation to food allergen sensitization, and any correlation to asthma control and asthma-related quality of life.

Methods

Perceived food hypersensitivity, as well as IgE sensitization to common food allergens, levels of exhaled nitric oxide (FeNO), and blood eosinophil counts (B-Eos) were assessed in 408 subjects (211 women) with asthma, aged (mean ± SEM) 20.4 ± 0.3 years. Subjects filled out the Asthma Control Test (ACT) and the Mini Asthma Quality of Life Questionnaire (Mini-AQLQ). Inflammation was assessed by means of FeNO and B-Eos.

Results

Fifty-three per cent of subjects reported food hypersensitivity. A corresponding food allergen sensitization was found in 68% of these subjects. Non-atopic subjects with perceived food hypersensitivity (n = 31) had lower ACT (19 (15 - 22) vs. 21 (20 - 23), p < 0.001) and Mini-AQLQ -scores (5.3 (4.3 - 6.1) vs. 6.1 (5.5 - 6.5), p < 0.001) than subjects with no food hypersensitivity (n = 190), despite lower levels of FeNO and B-Eos (p < 0.05).

Conclusions and Clinical Relevance

Food hypersensitivity was commonly reported among young asthmatics. In a majority of cases, a corresponding food allergen sensitization was found. A novel and clinically important finding was that non-atopic subjects with perceived food hypersensitivity were characterized by poorer asthma control and asthma-related quality of life.

A comprehensive review of sensitization and allergy to soy-based products

Since 1943, cases of sensitization or allergy to soy-based formulas (SBFs) have been described without any consensus on their real prevalence. We identified the adjusted prevalence of IgE-mediated soy allergies in children and performed a secondary analysis of the impact of age (less than and more than 6 months). We performed a systematic review with meta-analysis of studies published from 1909 to 2013 in PubMed, Embase, LILACS, ARTEMISA, Cochrane, Bandolier, DARE and the GRADE system for grading quality. Results are presented in tables and graphs using a forest plot. The 40 studies identified established weighted prevalence of soy allergies of 0 to 0.5 % (0.27) for the general population, 0.4 to 3.1 % (1.9) for the referred population, and 0 to 12.9 % (2.7) for allergic children. Prevalence of sensitization after the use of SBFs is 8.7 and 8.8 %, depending on the method used. The prevalence of allergies to soy and IgE sensitization to the use of SBFs is less than reported. Not enough evidence exists to show a higher risk of allergy in infants younger than 6 months. The concern about soy allergy is no reason to postpone the use of SBFs in IgE-mediated cow's milk allergy infants until the age of 6 months.

Food hypersensitivity in mexican adults at 18 to 50 years of age: a questionnaire survey

PURPOSE

There is limited epidemiological evidence of food hypersensitivity (FH) in the adult population. We aimed to determine the prevalence of FH in Mexican adults, their clinical features and to establish common food involved in its appearance.

METHODS

We designed a cross-sectional study using a fixed quota sampling; 1,126 subjects answered a structured survey to gather information related to FH.

RESULTS

The prevalence of FH in adults was 16.7% (95% CI, 14.5% to 18.8%), without statistical significant differences related to gender (women, 17.5% and men, 15.9%) or residential location. The most common clinical manifestations in adults with FH were oral allergy syndrome (70 of 1,126) and urticaria (55 of 1,126). According to category, fruits and vegetables were the most frequent foods to trigger FH (6.12%) and were individually related to shrimp (4.0%), and cow milk (1.5%). Adults under age 25 had a higher frequency of FH (OR, 1.39; 95% CI, 1.01 to 1.91, P <0.001). Personal history of any atopic disease was significantly associated with FH (P <0.0001).

CONCLUSIONS

The prevalence of FH is relatively high in Mexican adults, and FH is significantly associated with atopic diseases.

Natural history of perceived food hypersensitivity and IgE sensitisation to food allergens in a cohort of adults

Background

No longitudinal studies exist on the natural history of food hypersensitivity and IgE sensitisation to food allergens in adults.

Objective

To examine the natural history of food hypersensitivity, the natural history of IgE sensitisation to food allergens and to investigate the risk factors for new onset food hypersensitivity.

Methods

Food hypersensitivity was questionnaire-assessed in 2307 individuals (aged 20–45 years) from Iceland and Sweden during the European Community Respiratory Health Survey both at baseline and follow-up 9 years later. IgE food and aeroallergen sensitisation were assessed in a subgroup of these individuals (n = 807). Values of 0.35 kU/L and above were regarded as positive sensitisation.

Results

Food hypersensitivity was reported by 21% of the subjects and this proportion remained unchanged at follow-up (p = 0.58). Fruits, nuts and vegetables were the three most common causes of food hypersensitivity, with a similar prevalence at baseline and follow-up. The prevalence IgE sensitisation to food allergens decreased in general by 56% (p<0.001) and IgE sensitisation to peanut decreased in particular by 67% (p = 0.003). The prevalence of timothy grass IgE sensitisation decreased by 15% (p = 0.003) while cat, mite and birch IgE sensitisation did not decrease significantly. Female sex, rhinitis, eczema and presence of IgE sensitisation to aeroallergens were independently associated with new onset food hypersensitivity.

Conclusion

The prevalence of food hypersensitivity remained unchanged while the prevalence of IgE sensitisation to food allergens decreased in adults over a 9-year follow-up period. The decrease in prevalence of IgE sensitisation to food allergens was considerably larger than the change in prevalence of IgE sensitisation to aeroallergens.

Rectal bleeding in Egyptian children

AIM

In a prospective study to outline the aetiology of bleeding per rectum (BPR) in Egyptian infants and children, a subsidiary aim was to define some of the clinical characteristics of the different aetiologies.

SUBJECTS AND METHODS

194 children with BPR are described. The diagnostic work-up included laboratory investigations, radiological and endoscopic assessment, radio-isotope scanning, angiography and histopathological examination of mucosal biopsies, as appropriate.

RESULTS

Ages ranged from 3 to 192 months with a mean (SD) of 49.8 (43.5). Infectious enterocolitis was the most common cause (37.1%). Others included colorectal polyps (21.1%), chronic colitis (16%) including inflammatory bowel diseases (5.2%), allergic colitis (2.6%), solitary rectal ulcer syndrome (1.5%) and non-specific colitis (6.7%). Intussusception and Meckel's diverticulae were the cause in 7.3% and 2.6%, respectively, while other aetiologies included vascular (6.2%), systemic (3.6%), local anal (3.1%) and upper gastro-intestinal causes (1.5%). In 1.5% of cases, the cause remained 'obscure'.

CONCLUSION

In Egyptian children, infectious enterocolitis followed by colorectal polyps and chronic colitis are major causes of BPR.

Prevalence of food allergy in Taiwan: a questionnaire-based survey

AIM

Food allergy is common in children and adults, and could be potentially fatal in minor groups. It is important for physicians to identify the prevalence of food allergies and to recognise common food allergens to make precise diagnosis and choose correct therapeutic approaches.

METHODS

We used a nationwide, cross-sectional, random questionnaire-based survey to estimate the self-reported and expert-screened prevalence of food allergies and to identify the common food allergens in Taiwan. In this study, the perceptional diagnosis of food allergies was screened by physicians according to descriptions of convincing symptoms and medical recordings; in the meantime, non-allergic adverse reactions to foods, including food intolerance or food avoidance, were clarified.

RESULTS

A total of 30 018 individuals who met the inclusion criteria was evaluated, and 6.95% of them were diagnosed as victims of food allergies. The prevalence was 3.44% in children under 3 years of age, 7.65% in children aged 4-18 years and 6.40% in adults respectively. About 77.33% of the food allergy population had experienced recurrent allergic attacks. Systemic reactions happened about 4.89% in food allergies group. The most commonly reported food allergen in Taiwan is seafood, including shrimp, crab, fish and mollusc. In addition, mango, milk, peanuts and eggs were also important food allergens in the general population; while milk, shellfish, peanuts and eggs were common in children.

CONCLUSIONS

Less than 10% of the Taiwan population suffers from food allergy with different allergic symptoms to variable food allergens in different age groups.

The epidemiology of food allergy in Europe: protocol for a systematic review

Background

The European Academy of Allergy and Clinical Immunology is in the process of developing its Guideline for Food Allergy and Anaphylaxis, and this protocol of a systematic review is one of seven inter-linked evidence syntheses that are being undertaken in order to provide a state-of-the-art synopsis of the current evidence base in relation to epidemiology, prevention, diagnosis and clinical management and impact on quality of life, which will be used to inform the formulation of clinical recommendations.

The aims of the systematic review will be to understand and describe the epidemiology of food allergy, i.e. frequency, risk factors and outcomes of patients suffering from food allergy, and to describe how these characteristics vary by person, place and time.

Methods

A highly sensitive search strategy has been developed to retrieve articles that have investigated the various aspects of the epidemiology of food allergy. The search will be implemented by combining the concepts of food allergy and its epidemiology from electronic bibliographic databases.

Discussion

This systematic review will provide the most up to date estimates of the frequency of food allergy in Europe. We will attempt to break these down by age and geographical region in Europe. Our analysis will take into account the suitability of the study design and the respective study biases that could affect exposure and outcome. We will examine the different methods to diagnose food allergy and the associated measures of occurrence.

Exploring the Determinants of the Perceived Risk of Food Allergies in Canada

Food allergies are emerging health risks in much of the Western world, and some evidence suggests prevalence is increasing. Despite lacking scientific consensus around prevalence and management, policies and regulations are being implemented in public spaces (e.g., schools). These policies have been criticized as extreme in the literature, in the media, and by the non-allergic population. Backlash appears to be resulting from different perceptions of risk between different groups. This article uses a recently assembled national dataset (n = 3,666) to explore how Canadians perceive the risks of food allergy. Analyses revealed that almost 20% self-report having an allergic person in the household, while the average respondent estimated the prevalence of food allergies in Canada to be 30%. Both of these measures overestimate the true clinically defined prevalence (7.5%), indicating an inflated public understanding of the risks of food allergies. Seventy percent reported food allergies to be substantial risks to the Canadian population. Multivariate logistic regression models revealed important determinants of risk perception including demographic, experience-based, attitudinal, and regional predictors. Results are discussed in terms of understanding emerging health risks in the post-industrial era, and implications for both policy and risk communication.

Conflicting sensory relationships. Encounters with allergic people

Increasingly, people employ the term 'allergy' to define various pathological conditions, although the biomedical community lacks a consensus on a definition of the term. It has become a widespread and convenient label for diverse conditions, often going beyond biomedical diagnosis. The aim of this paper is to explore how allergic people narrate their illness experiences, focusing specifically on the relationship between words, senses and bodies. This paper is based on an ethnographic study in a medium-sized north Italian city conducted from 2004 to 2008, starting in a public hospital Allergy Unit, and then developing through snowball recruitment and referral methods. Interviews were conducted with 37 allergic people, four allergologists and four nurses. Allergic people's narratives constantly drew upon two main concepts: weakness and pollution. These are interpreted as sensorial dimensions expressing a conflicting relationship with the outside environment. It is argued that in times of marked individualism and social transformations, bodily states are of fundamental importance and the mobilisation of sensory concepts is an attempt to give order and meaning to a world that is perceived as constituted by threatening aspects, polluted and out of order.

Prevalence of food avoidance and food allergy in Chinese patients with chronic urticaria

BACKGROUND

Food avoidance is common among Chinese patients with chronic urticaria because food allergy is considered to be the cause of disease. The benefit of food avoidance and its relationship with food allergy is unknown.

OBJECTIVES

The aims of this study were to examine the prevalence and effect of food avoidance and food allergy in patients with chronic urticaria.

METHODS

Four hundred and ninety-four patients with chronic urticaria, who attended Peking University Third Hospital from January 2009 to December 2010, were studied. Food avoidance and its effect were investigated with a detailed questionnaire. Food allergy was diagnosed by serum food-specific immunoglobulin E (IgE), elimination diet based on food-specific IgE, and open food challenge.

RESULTS

One hundred and fifty-eight patients (32%) avoided fish, shrimp, crab, lamb or beef prior to evaluation and 82·9% of them reported food avoidance ineffective. Out of 341 patients tested for serum food-specific IgE, 75 (22%) were positive, with soy, peanut, beef, lamb, chicken, crab and shrimp as the leading allergens. Chronic urticaria induced by food allergy was found in only 2·8% of patients.

CONCLUSIONS

The prevalence of food avoidance is high and mostly ineffective in Chinese patients with chronic urticaria. Foods avoided do not correspond to serum food-specific IgE. The incidence of IgE-mediated urticaria, as demonstrated by open food challenge, is low. Physicians and patients should be aware of unnecessary dietary avoidance while seeking treatment of chronic urticaria.

Prevalence of wheat allergy in Japanese adults

BACKGROUND

Wheat is one of the most common causes of food allergies. The exact prevalence of wheat allergy has not been well delineated in Japanese adults.

METHODS

We enrolled 935 adults in a cohort study established by Shimane University in order to examine the determinants of lifestyle-related diseases. A screening was conducted by a questionnaire-based examination and a detection of serum omega-5 gliadin-specific IgE. Subjects who tested positive in the questionnaire-based examination and/or the serum omega-5 gliadin-specific IgE test were further examined by detailed interviews and skin prick tests.

RESULTS

A total of 22 subjects were picked up by the screening process, and 17 of these were further examined by secondary testing. Only two subjects were conclusively identified as having wheat allergy.

CONCLUSIONS

The prevalence of wheat allergy in Japanese adults was found to be 0.21% by using a combination of questionnaire-based examination, skin prick test and serum omega-5 gliadin-specific IgE test.

An internet survey on self-reported food allergy in Greece: clinical aspects and lack of appropriate medical consultation

BACKGROUND

Food allergy (FA) represents a common and worldwide disorder but in publications referring to FA the reported diagnosis is rarely confirmed. Consequently, the subjectively assessed FA may negatively affect the quality of life of patients and their families.

OBJECTIVE

We have conducted this internet survey in order to estimate the self-reported perception of FA in Greece.

METHODS

A standard anonymous questionnaire was posted for a 3-month period on http://www.in.gr, a Greek popular Internet portal. Each individual could participate only once. Participants were screened for the presence or history of FA by a key question and were then asked to provide information on symptoms, course and management.

RESULTS

A total of 3673 adult subjects (mean age 34.2 years, range 18-74, females 61.3%), reporting FA were included in analysis. Most reported reactions were related to fruits (14.9%), seafood (10.7%) and nuts (9.2%). The first episode occurred principally during the second (29.2%) and third (30.9%) decade within 3 h from consumption (82.2%). Predominant symptoms were urticaria and oral allergy syndrome (almost 25% each one). Nearly half of the participants sought no medical advice, while 31.4% asked for an allergist's consultation. Almost 21% of reactors were hospitalized; nuts, severity of symptoms (lower respiratory and/or cardiovascular), onset in lower age, previous exercise and concomitant alcohol and/or aspirin intake were positively associated with hospitalization.

CONCLUSION

Although FA causes severe anaphylactic episodes, almost 50% of individuals who experience symptoms perceived as FA do not seek medical advice. Awareness programmes must be carried out in order to increase consciousness about this potentially fatal medical condition.

Cow's milk allergy as a global challenge

PURPOSE OF REVIEW

Cow's milk is a leading cause of food allergy especially in infants and children. 'Diagnosis and Rationale for Action against Cow's Milk Allergy' published by the World Allergy Organization has underlined that there is not enough information concerning geographical trends in cow's milk allergy (CMA) in children or adults. Experts from Australia, Asia, North America, Latin America, the Middle East and Europe have gathered together in a 2-day meeting in order to present various regional approaches to CMA. This report is a summary of the information that was presented at this meeting.

RECENT FINDINGS

Even though there seems to be uniformity concerning the diagnosis and treatment of CMA, the diagnostic approach to CMA shows variations among different regions. Common concerns were inadequate applications of challenge tests for the diagnosis and inadequate supply of the cow's milk substitute formulas.

SUMMARY

CMA is a global challenge and collaboration of the national and international scientific communities is essential to produce and update practical guidelines for CMA.

Diagnosis and Rationale for Action Against Cow's Milk Allergy (DRACMA): a summary report

The 2nd Milan Meeting on Adverse Reactions to Bovine Proteins was the venue for the presentation of the first consensus-based approach to the management of cow's milk allergy. It was also the first time that the Grading of Recommendations, Assessments, Development, and Evaluation approach for formulating guidelines and recommendations was applied to the field of food allergy. In this report we present the contributions in allergen science, epidemiology, natural history, evidence-based diagnosis, and therapy synthesized in the World Allergy Organization Diagnosis and Rationale for Action against Cow's Milk Allergy guidelines and presented during the meeting. A consensus emerged between discussants that cow's milk allergy management should reflect not only basic research but also a newer and better appraisal of the literature in the light of the values and preferences shared by patients and their caregivers in partnership. In the field of diagnosis, atopy patch testing and microarray technology have not yet evolved for use outside the research setting. With foreseeable breakthroughs (eg, immunotherapy and molecular diagnosis) in the offing, the step ahead in leadership can only stem from a worldwide organization implementing consensus-based clinical practice guidelines to diffuse and share clinical knowledge.

Food allergy in Lebanon: is sesame seed the "middle eastern" peanut

A randomly sampled, cross-sectional serology test-based survey was conducted in Lebanon to describe the pattern of food allergy among Lebanese population. The prevalence of specific Immunoglobulin E (IgE) to food allergens was investigated in 20 laboratories in different regions of Lebanon by an immunoblot assay over a 1 year period. Clinical correlation was determined in two university hospitals. There were 1842 patients with suspected IgE-mediated food allergic reactions tested for specific IgE upon their physician's request. Clinical correlation was done in 93 patients. We identified 386 out of 1842 (20.95%) patients with positive specific IgE to food allergens. The clinical presentations were cutaneous, digestive, and anaphylaxis. The major cause of allergy was cow's milk in infants and young children, hazelnut and wheat flour in adults. Although specific IgE to peanut in infants, children, and adults were higher than for sesame, peanut-induced allergic reactions were mild, in contrary to sesame where anaphylaxis was the only clinical manifestation. Recently, sesame has been recognized as an increasingly frequent and potentially severe allergen. Further studies with double-blind, placebo-controlled food challenge are needed to establish the real prevalence of food allergy in Lebanon, and to determine the most common allergens taking in consideration the nutritional habits of our population.

Food allergy among children in the United States

OBJECTIVES

The goals were to estimate the prevalence of food allergy and to describe trends in food allergy prevalence and health care use among US children.

METHODS

A cross-sectional survey of data on food allergy among children <18 years of age, as reported in the 1997-2007 National Health Interview Survey, 2005-2006 National Health and Nutrition Examination Survey, 1993-2006 National Hospital Ambulatory Medical Care Survey and National Ambulatory Medical Care Survey, and 1998-2006 National Hospital Discharge Survey, was performed. Reported food allergies, serum immunoglobulin E antibody levels for specific foods, ambulatory care visits, and hospitalizations were assessed.

RESULTS

In 2007, 3.9% of US children <18 years of age had reported food allergy. The prevalence of reported food allergy increased 18% (z = 3.4; P < .01) from 1997 through 2007. In 2005-2006, serum immunoglobulin E antibodies to peanut were detectable for an estimated 9% of US children. Ambulatory care visits tripled between 1993 and 2006 (P < .01). From 2003 through 2006, an estimated average of 317000 food allergy-related, ambulatory care visits per year (95% confidence interval: 195000-438000 visits per year) to emergency and outpatient departments and physician's offices were reported. Hospitalizations with any recorded diagnoses related to food allergy also increased between 1998-2000 and 2004-2006, from an average of 2600 discharges per year to 9500 discharges per year (z = 3.4; P < .01), possibly because of increased use of food allergy V codes.

CONCLUSION

Several national health surveys indicate that food allergy prevalence and/or awareness has increased among US children in recent years.

Development of a food allergy education resource for primary care physicians

BACKGROUND

Food allergy is estimated to affect 3-4% of adults in the US, but there are limited educational resources for primary care physicians. The goal of this study was to develop and pilot a food allergy educational resource based upon a needs survey of non-allergist healthcare providers.

METHODS

A survey was undertaken to identify educational needs and preferences for providers, with a focus on physicians caring for adults and teenagers, including emergency medicine providers. The results of the survey were used to develop a teaching program that was subsequently piloted on primary care and emergency medicine physicians. Knowledge base tests and satisfaction surveys were administered to determine the effectiveness of the educational program.

RESULTS

Eighty-two physicians (response rate, 65%) completed the needs assessment survey. Areas of deficiency and educational needs identified included: identification of potentially life-threatening food allergies, food allergy diagnosis, and education of patients about treatment (food avoidance and epinephrine use). Small group, on-site training was the most requested mode of education. A slide set and narrative were developed to address the identified needs. Twenty-six separately enrolled participants were administered the teaching set. Pre-post knowledge base scores increased from a mean of 38% correct to 64% correct (p < 0.001). Ability to correctly demonstrate the use of epinephrine self injectors increased significantly. Nearly all participants (>95%) indicated that the teaching module increased their comfort with recognition and management of food allergy.

CONCLUSION

Our pilot food allergy program, developed based upon needs assessments, showed strong participant satisfaction and educational value.

Prevalence of legume sensitization in patients with naso-bronchial allergy

Prevalence of legume allergy and concomitant sensitization to different allergens was evaluated in patients of asthma and/ or rhinitis. Skin prick test with 27 common food allergens and 61 aeroallergens in 76 subjects was performed. Out of 76 subjects, 41 perceived allergenic problems with different food items as contributing factor. Only six patients showed prick test positivity compatible with their anamnesis. However, 35 subjects showed sensitization to different food items, out of which thirty were sensitive to legumes. The common foods in decreasing order of allergenicity were chickpea, followed by green gram, egg white, and bean fresh/red gram. Concomitant sensitization to different legume crops was found in patients.

Gut eosinophilia in food allergy and systemic and autoimmune diseases

Eosinophilic gastroenteritis is a rare disease characterized by striking tissue eosinophilia in any layer of the gut wall; however, many diseases can cause increased gut eosinophilia. Allergic reactions to food are an important cause of gut eosinophilia. Not all adverse reactions to food are IgE mediated, and most cases of IgE-mediated food allergy do not have eosinophilic gastroenteritis. Parasitic, bacterial, and viral pathogens as well as certain systemic diseases such as vasculitis can cause gut eosinophilia. These heterogeneous conditions are reviewed in this article.

Survey of physicians' approach to food allergy, Part 2: Allergens, diagnosis, treatment, and prevention

BACKGROUND

Food allergy (FA) practice varies widely.

OBJECTIVE

To report differences between allergists and nonallergists regarding diagnosis, treatment, and prevention of FA.

METHODS

A 2-page questionnaire was mailed to 3,000 allergists and 4,000 nonallergists. We previously published the findings on prevalence and manifestations. Herein, we report the findings on food allergens, diagnosis, treatment, and prevention.

RESULTS

Responses were received from 584 (19.5%) of the allergists and 77 (1.9%) of the nonallergists. Because of the nonallergists' low response rate, descriptive comparisons were made without emphasis on statistical significance. Allergists and nonallergists differed in their rankings of the 5 most common food allergens. Nonallergists differed markedly from allergists in the diagnostic methods, using more leukocytotoxic tests (10.9% vs 0.3%), specific IgG4 tests (33.8% vs 6.0%), and intradermal tests (40.0% vs 9.5%), but fewer percutaneous skin tests (44.7% vs 98.9%), specific IgE tests (73.4% vs 97.8%), and challenges (61.1% vs 87.6%). They also differed in their use of open, single-blind, and double-blind challenge tests. Allergists were more likely to rely on elimination of proven food allergens and less likely to use conventional elimination diets, rotation diets, and sublingual or subcutaneous hyposensitization. Allergists were more likely to recommend a diet regimen during pregnancy (76.7% vs 35.3%) and lactation (91.1% vs 72.9%), breastfeeding (93.6% vs 84.3%), hydrolysate formulas (83.5% vs 64.3%), and withholding solids until the age of 6 months (89.4% vs 70.0%).

CONCLUSION

Differences were noted between nonallergists and allergists regarding causes, diagnostic methods, treatment, and prevention of FA, indicating the need for more education in this area.

The prevalence of plant food allergies: a systematic review

BACKGROUND

There is uncertainty regarding the prevalence of allergies to plant food.

OBJECTIVE

To assess the prevalence of allergies to plant food according to the different subjective and objective assessment methods.

METHODS

Our systematic search of population-based studies (since 1990) in the literature database MEDLINE focused on fruits, vegetables/legumes, tree nuts, wheat, soy, cereals, and seeds. Prevalence estimates were categorized by food item and method used (food challenges, skin prick test, serum IgE, parent/self-reported symptoms), complemented by appropriate meta-analyses.

RESULTS

We included 36 studies with data from a total of over 250,000 children and adults. Only 6 studies included food challenge tests with prevalences ranging from 0.1% to 4.3% each for fruits and tree nuts, 0.1% to 1.4% for vegetables, and < 1% each for wheat, soy, and sesame. The prevalence of sensitization against any specific plant food item assessed by skin prick test was usually < 1%, whereas sensitization assessed by IgE against wheat ranged as high as 3.6% and against soy as high as 2.9%. For fruit and vegetables, prevalences based on perception were generally higher than those based on sensitization, but for wheat and soy in adults, sensitization was higher. Meta-analyses showed significant heterogeneity between studies regardless of food item or age group.

CONCLUSION

Population-based prevalence estimates for allergies to plant products determined by the diagnostic gold standard are scarce. There was considerable heterogeneity in the prevalence estimates of sensitization or perceived allergic reactions to plant food.

Survey of physicians' approach to food allergy, Part 1: Prevalence and manifestations

INTRODUCTION

Food allergy (FA) prevalence is increasing and is being popularly claimed by the general population.

OBJECTIVE

To evaluate attitudinal differences between allergists and nonallergists with regard to prevalence, manifestations, offending food component, and time of onset of FA reactions.

METHODS

A 2-page questionnaire was mailed to 3,000 members of the American College of Allergy, Asthma and Immunology and 4,000 nonallergists (1,000 each of internists, pediatricians, family practitioners, and otolaryngologists).

RESULTS

Responses were received from 584 allergists and 77 nonallergists. The overall estimated prevalence of FA was significantly higher for nonallergists than allergists (12.1% vs 4.6%) and in each age group. The most common gastrointestinal manifestation of FA was oropharyngeal itching according to allergists (67.2%) vs diarrhea according to nonallergists (42.5%). More nonallergists than allergists reported neurobehavioral manifestations, musculoskeletal symptoms, and upper airway symptoms as common in FA. On the other hand, more allergists than nonallergists considered atopic dermatitis, acute urticaria or angioedema, and anaphylaxis to be common. Nonallergists considered carbohydrates, fat, and additives as causing allergy much more than allergists did (34.4% vs 6.9%; P < .001). With regard to time of onset of FA, nonallergists had higher estimates than allergists for both late (25.5.% vs 13.0%; P < .001) and delayed (22.1% vs 4.5%; P < .001) reactions.

CONCLUSION

Significant differences in attitudes toward FA were revealed between allergists and nonallergists, which highlights the need to enhance education in this area.

The prevalence of food allergy: a meta-analysis

BACKGROUND

There is uncertainty about the prevalence of food allergy in communities.

OBJECTIVE

To assess the prevalence of food allergy by performing a meta-analysis according to the method of assessment used.

METHODS

The foods assessed were cow's milk, hen's egg, peanut, fish, shellfish, and an overall estimate of food allergy. We summarized the information in 5 categories: self-reported symptoms, specific IgE positive, specific skin prick test positive, symptoms combined with sensitization, and food challenge studies. We systematically searched MEDLINE and EMBASE for publications since 1990. The meta-analysis included only original studies. They were stratified by age groups: infant/preschool, school children, and adults.

RESULTS

A total of 934 articles were identified, but only 51 were considered appropriate for inclusion. The prevalence of self-reported food allergy was very high compared with objective measures. There was marked heterogeneity between studies regardless of type of assessment or food item considered, and in most analyses this persisted after age stratification. Self-reported prevalence of food allergy varied from 1.2% to 17% for milk, 0.2% to 7% for egg, 0% to 2% for peanuts and fish, 0% to 10% for shellfish, and 3% to 35% for any food.

CONCLUSION

There is a marked heterogeneity in the prevalence of food allergy that could be a result of differences in study design or methodology, or differences between populations.

CLINICAL IMPLICATIONS

We recommend that measurements be made by using standardized methods, if possible food challenge. We need to be cautious in estimates of prevalence based only on self-reported food allergy.

Prevalence of self-reported food allergy in American adults and use of food labels

BACKGROUND

Few population-based studies in the United States have determined the prevalence of food allergy in adults and the problems these individuals might have with reading food labels.

OBJECTIVE

The objectives of this study are to report the prevalence of self-reported food allergy, to identify the characteristics of food allergy reactions, and to describe the use of labels among adults with food allergy.

METHODS

Questions from the US Food and Drug Administration's 2001 Food Safety Survey were analyzed to determine the prevalence of food allergy and opinions about food labels in the management of food allergy.

RESULTS

The prevalence of self-reported food allergy is 9.1% among all survey respondents, with 5.3% of all respondents reporting a doctor-diagnosed food allergy. The prevalence of food allergy to the 8 most common allergens (peanut, tree nuts, egg, milk, wheat, soybeans, fish, and crustacean shellfish) is self-reported as 2.7% among respondents with doctors' diagnoses. Several label issues, such as words on some ingredient lists being too technical or hard to understand and food labels not always alerting persons to new ingredients, were reported as serious or very serious obstacles for managing an allergy.

CONCLUSION

The prevalence of self-reported doctor-diagnosed food allergy among US adults is 5.3%, and a large portion of adults with food allergy found certain label issues a serious problem for managing their food allergy.

CLINICAL IMPLICATIONS

The findings provide a needed source of population-based prevalence data of food allergy among US adults. Label issues identified are useful in understanding the difficulties of managing a food allergy.

Coping with Food Allergy: Exploring the Role of the Online Support Group

The aims of this study were to explore the reasons for participation in an online support group for individuals affected by food allergy, its perceived advantages and disadvantages as well as impact on the relationship with healthcare providers. A total of 32 members of the Food Allergy Survivors Together (F.A.S.T.) online support group completed an online structured interview and responses were analysed using thematic analysis. Group members identified a range of benefits, including accessibility, receipt of social support as well as guidance on coping strategies. The only disadvantages identified revolved around the accuracy and trust in information exchanged via the group bulletin board. Group participation did appear to impact on relationships with healthcare providers with several members reporting greater empowerment through decision-making, though in contrast some experienced difficulties in discussing their online support experiences and information obtained with their healthcare providers.

Study of food allergy in the Spanish population

BACKGROUND

The aim of the study was to investigate the prevalence of food allergy in patients referred to our Allergy Unit and to evaluate the diagnostic methods used.

METHODS

We selected 674 patients referred to the Allergy Unit of our hospital from May 2002 to October 2004. The prevalence of symptoms was determined by a standardized questionnaire, prick-prick test, and serum specific IgE. In a second phase, double-blind oral challenge tests were administered.

RESULTS

Food allergy was found in 106 patients (15.7 %): 71 adults (67 %) and 35 children (33 %). The prevalence of food allergen sensitization was 14 % in adults and 20.8 % in children. A total of 89.6 % of the patients experienced symptoms immediately. Only 29.2 % the patients of sought medical attention and adrenaline was administered to five (16.1 %). The foods most frequently involved in allergic reactions were fruits (56.6 %) and tree nuts (22.6 %). The most common symptoms were oral allergy syndrome (46.2 %), urticaria (32.1 %), and anaphylaxis (14.2 %). Combining the results of the questionnaire with those of prick-prick tests in patients whose allergy was confirmed by double-blind, placebo-controlled food challenge (9.1 %) showed a sensitivity of 95.5 %, a negative predictive value of 96 %, a specificity of 75 % and a positive predictive value of 73 %.

CONCLUSIONS

1. The prevalence of food allergy in our sample was 9.1 %. 2. The foods most frequently involved in allergic reactions were fruits and tree nuts. 3. The most common symptoms were oral allergy syndrome, urticaria, and anaphylaxis. 4. Combining our questionnaire with in vivo tests allowed us to diagnose 75-96 % of patients with no food allergy and 95 % of food allergy patients.

Prevalence of sensitization to food allergens, reported adverse reaction to foods, food avoidance, and food hypersensitivity among teenagers

BACKGROUND

There is a paucity of information on food hypersensitivity (FHS) among teenagers.

OBJECTIVES

We sought to investigate the sensitization rates, perception of FHS, food avoidance, and FHS assessed by means of food challenges among teenagers.

METHODS

This cohort study recruited 757 eleven-year-olds and 775 fifteen-year-olds in the United Kingdom. Sensitization rates, reported rates of FHS, and rates of food avoidance were measured. The prevalence of FHS was established by using food challenges.

RESULTS

The prevalence of reported FHS among the 11- and 15-year-old cohorts was 11.6% (90/775) and 12.4% (94/757), respectively. One hundred twenty-two (15.7%) and 142 (18.7%) of the 11- and 15-year-olds reported they were avoiding some food. The rates of sensitization to the food allergens were 5.1% (36/699) and 4.9% (32/649) for the 11- and 15-year-olds, respectively. FHS was confirmed in 8 (1.0%) 11-year-old children and 8 (1.0%) 15-year-old children by means of open food challenge and in 1 (0.1%) 11-year-old and 4 (0.5%) 15-year-olds by means of double-blind, placebo-controlled food challenge. The prevalence of FHS, as confirmed by using open food challenges and positive skin prick test responses plus a history of adverse reactions, was 18 (2.3%) of 775 in the 11-year-old cohort and 17 (2.3%) of 757 in the 15-year-old cohort.

CONCLUSIONS

The rate of reported FHS was significantly more than sensitization to the predetermined allergens (odds ratio, 2.17; 95% CI, 1.47-3.18; P < .001 in the 11-year-olds; odds ratio, 2.73; 95% CI, 1.81-4.13; P < .001 in the 15-year-olds). By means of objective assessment, 2.3% of both 11- and 15-year-old children had FHS, with the majority showing immediate reactions.

Allergy-like conditions and health-care contacts among children with exclusion diets at school

AIM

To find out whether children with exclusion diet at school had allergy-like conditions that could explain their food avoidance, the objective of this study was to describe health-care contacts and diagnostic testing among schoolchildren with exclusion diet and compare the magnitude of allergy-like conditions between those children who had vs. had not consulted health-care professionals. Telephone interviews were conducted with the parents of 230 schoolchildren, aged 6-18 years, with certificates for exclusion diets at school.

RESULTS

The majority of the schoolchildren (85%) had consulted health-care professionals for food-related problems, and 68% were doctor-diagnosed as having food hypersensitivity. Those who had consulted health-care professionals specifically for their food-related problems had more complex and severe problems compared with those who had not consulted health-care professionals. Breathing difficulties (27/196) and anaphylaxis (9/196) related to intake of food were reported only for those who had sought health-care professionals (n = 196). Regardless of whether the children had consulted the health-care professionals, their food-related problems were consistent with food hypersensitivity. Schoolchildren avoided food items known to be associated with food hypersensitivity such as tree nuts, fruit, egg, peanut, lactose and fish. Furthermore, 83% of the 230 children also had allergic diseases (i.e. asthma, eczema or hay fever) or were hypersensitive to other substances besides food, and 83% had at least one sibling or parent with hypersensitivity to foods or other substances.

CONCLUSIONS AND IMPLICATIONS FOR THE SCHOOL NURSE

Schoolchildren with food certificates for exclusion diets, based on parents' statements, have food-related and allergy-like problems that may well motivate exclusion diets at school. The school nurses can rely on the parents' information as to what foods their children should avoid, even when doctor diagnoses have not been made or health-care consultations have not been carried out.

Fish and shellfish allergy

Fish and shellfish are important in the American diet and economy. Nearly $27 billion are spent each year in the United States on seafood products. Fish and shellfish are also important causes of food hypersensitivity. In fact, shellfish constitute the number one cause of food allergy in the American adult. During the past decade, much has been learned about allergens in fish and shellfish. The major allergens responsible for cross-reactivity among distinct species of fish and amphibians are parvalbumins. The major shellfish allergen has been identified as tropomyosin. Many new and important potential cross-reacting allergens have been identified within the fish family and between shellfish, arachnids, and insects. Extensive research is currently underway for the development of safer and more effective methods for the diagnosis and management of fish and shellfish hypersensitivity.

Reduced immunoglobulin E and allergy among adults with glioma compared with controls

We and others have reported previously that adults with glioma are 1.5- to 4-fold less likely than controls to report a variety of allergic conditions. The consistent nature of this relationship calls for a biological explanation so that preventative or therapeutic modalities can be explored. We enrolled 403 newly diagnosed adult glioma cases in the San Francisco Bay Area over a 3-year period using a population-based cancer registry and 402 age/gender/ethnicity frequency-matched controls identified via random digit dialing. We assessed total, food-specific, and respiratory-specific IgE in available case (n = 228) and control (n = 289) serum samples. IgE levels were associated with gender, age, smoking status, and ethnicity among cases and/or controls. Among the cases, IgE levels were not associated with aspects of glioma therapy including radiation, chemotherapy, or tumor resection. Total IgE levels were lower in cases than controls: age/gender/ethnicity/education/smoking-adjusted odds ratio (OR) for elevated versus normal total IgE was 0.37 [95% confidence interval (CI), 0.22-0.64]. For the food panel, OR was 0.12 (95% CI, 0.04-0.41). For the respiratory panel, OR was 0.76 (95% CI, 0.52-1.1). Among respiratory allergies, late age of onset (>12 years) but not IgE levels defined a group with strong associations with risk (OR, 0.50; 95% CI, 0.33-0.75). These results corroborate and strengthen our findings of an inverse association between allergic reactions and glioma by showing a relationship with a biomarker for allergy and cancer for the first time. Furthermore, the results indicate a complex relationship between allergic disease and glioma risk that varies by allergen and allergic pathology.

Food allergy and non-allergic food hypersensitivity in children and adolescents

BACKGROUND

Previous studies have shown a 10-fold discrepancy of self-reported food-induced symptoms and physician-diagnosed food hypersensitivity. Little information is available on the prevalence of food hypersensitivity in unselected paediatric populations. No data were available for German children.

OBJECTIVE

To study the perception of food-induced symptoms in the paediatric population, to investigate the allergens accused, to objectify patients' reports, and to identify subgroups at risk of having food-induced allergy (FA) or non-allergic food hypersensitivity (NAFH) reactions.

METHODS

This paper presents the data of the paediatric group (0-17 years) of a representative, randomly sampled, cross-sectional population-based survey studying 13 300 inhabitants of the German capital city Berlin regarding food-related symptoms. Instruments included mailed questionnaires, structured telephone interviews, physical examination, skin-prick tests, specific serum IgE and standardized, controlled and blinded oral food challenges.

RESULTS

Two thousand three hundred and fifty-four individuals were contacted by mailed questionnaire, 739 (31.4%) responses could be fully evaluated. Four hundred and fifty-five (61.5%) participants reported symptoms related to food ingestion, 284 (38.4%) affirmed reproducible symptoms in the standardized telephone interview. One hundred and eighty-four (24.8%) individuals were fully examined. Reproducible symptoms to food were found in 31 (4.2%) children and adolescents: 26 (3.5%) showed symptoms of FA and five (0.7%) of NAFH. The oral allergy syndrome was most often observed. Foods most commonly identified by oral challenges were apple, hazelnut, soy, kiwi, carrot and wheat.

CONCLUSION

The perception of food-related symptoms is common among children and adolescents from the general population. Self-reports could be confirmed in around one out of 10 individuals, still resulting in 4.2% of proven clinical symptoms. However, most reactions were mild and mainly because of pollen-associated FA, while NAFH reactions were less common. Severe IgE-mediated FA was observed in individuals with pre-existing atopic disease, who should be fully investigated for clinically relevant FA.