Temporal trends in prevalence of food allergy in Canada

Preparing Patients for Oral Immunotherapy (PPOINT): International Delphi consensus for procedural preparation and consent

BACKGROUND

Despite the promise of oral immunotherapy (OIT) to treat food allergies, this procedure is associated with potential risk. There is no current agreement about what elements should be included in the preparatory or consent process.

OBJECTIVE

We developed consensus recommendations about the OIT process considerations and patient-specific factors that should be addressed before initiating OIT and developed a consensus OIT consent process and information form.

METHODS

We convened a 36-member Preparing Patients for Oral Immunotherapy (PPOINT) panel of allergy experts to develop a consensus OIT patient preparation, informed consent process, and framework form. Consensus for themes and statements was reached using Delphi methodology, and the consent information form was developed.

RESULTS

The expert panel reached consensus for 4 themes and 103 statements specific to OIT preparatory procedures, of which 76 statements reached consensus for inclusion specific to the following themes: general considerations for counseling patients about OIT; patient- and family-specific factors that should be addressed before initiating OIT and during OIT; indications for initiating OIT; and potential contraindications and precautions for OIT. The panel reached consensus on 9 OIT consent form themes: benefits, risks, outcomes, alternatives, risk mitigation, difficulties/challenges, discontinuation, office policies, and long-term management. From these themes, 219 statements were proposed, of which 189 reached consensus, and 71 were included on the consent information form.

CONCLUSION

We developed consensus recommendations to prepare and counsel patients for safe and effective OIT in clinical practice with evidence-based risk mitigation. Adoption of these recommendations may help standardize clinical care and improve patient outcomes and quality of life.

Milk-induced anaphylaxis among children presenting to Canadian emergency departments

BACKGROUND

Cow's milk is one of the most common and burdensome allergens in pediatrics, and it can induce severe anaphylactic reactions in children. However, data on cow's milk-induced anaphylaxis are sparse.

OBJECTIVE

To describe the epidemiology of pediatric cow's milk-induced anaphylaxis and to determine risk factors for repeat emergency department (ED) epinephrine administration.

METHODS

Between April 2011 and May 2023, data were collected on children with anaphylaxis presenting to 10 Canadian EDs. A standardized form documenting symptoms, triggers, treatment, and outcome was used. Multivariate logistic regression was used.

RESULTS

Of 3118 anaphylactic reactions, 319 milk-induced anaphylaxis cases were identified (10%). In the prehospital setting, 54% of patients with milk-induced anaphylaxis received intramuscular epinephrine. In those with milk-induced anaphylaxis, receiving epinephrine before presenting to the ED was associated with a reduced risk of requiring 2 or more epinephrine doses in the ED (adjusted odds ratio, 0.95 [95% CI, 0.90-0.99]). Children younger than 5 years of age were more likely to experience a mild reaction compared with that in older children, who experienced a moderate reaction more often (P < .0001). Compared with other forms of food-induced anaphylaxis, children presenting with milk-induced anaphylaxis were younger; a greater proportion experienced wheezing and vomiting, and less experienced angioedema.

CONCLUSION

Prehospital epinephrine in pediatric milk-induced anaphylaxis is underused; however, it may decrease risk of requiring 2 ED epinephrine doses. Milk-induced anaphylaxis in children younger than 5 years of age may be less severe than in older children. Wheezing and vomiting are more prevalent in milk-induced anaphylaxis compared with that of other foods.

Clinical characteristics and management of pediatric egg-induced anaphylaxis: A cross-sectional study

BACKGROUND

Egg is the third most common food allergy in children; however, data on pediatric egg-induced anaphylaxis are sparse.

OBJECTIVE

To describe the clinical characteristics, management, and outcomes of pediatric egg-induced anaphylaxis.

METHODS

Children presenting with anaphylaxis were recruited from 13 emergency departments as part of the Cross-Canada Anaphylaxis Registry, from which data on anaphylaxis triggered by egg were extracted. Multivariate logistic regression was used to determine factors associated with prehospital epinephrine autoinjector (EAI) use and to compare anaphylaxis triggered by egg with other triggers of food-induced anaphylaxis (FIA).

RESULTS

We recruited 302 children with egg-induced anaphylaxis. The mean age was 2.6 years (SD = 3.6), and 55.3% were male. Only 39.4% had previously been diagnosed with an egg allergy. Prehospital EAI use was 32.1%, but this was not significantly lower than in other triggers of FIA (P = .26). Only 1.4% of patients required hospital admission. Relative to other triggers of FIA, patients with egg-induced anaphylaxis were significantly younger (P < .001) and exhibited more vomiting (P = .0053) and less throat tightness (P = .0015) and angioedema (P < .001).

CONCLUSION

To the best of our knowledge, this is the largest published cohort of pediatric egg-induced anaphylaxis. In this cohort, prehospital EAI use was very low. In addition, we identified certain symptoms that distinguish egg-induced from other triggers of FIA. Taken together, high suspicion is crucial in identifying egg-induced anaphylaxis, given the younger patient demographic and frequent lack of FIA history.

Age-Related Food Aversion and Anxiety Represent Primary Patient Barriers to Food Oral Immunotherapy

BACKGROUND

Although oral immunotherapy (OIT) for food allergy is a reasonable treatment option, barriers to this procedure's implementation have not been extensively evaluated from a patient perspective.

OBJECTIVE

We evaluated the barriers patients face during OIT administration, including anxiety and taste aversion, and the role of health care professionals, especially dietitians.

METHODS

A survey in Canada and the United States involved families currently enrolled in food OIT programs.

RESULTS

Of responses from 379 participants, fear of reaction was the most common barrier to OIT initiation, with 45.6% reporting it being a "very significant" barrier with other fears reported. However, taste aversion represented the prominent obstacle to continuation. Taste aversion was associated with a slower buildup (P = .02) and a reduction in dose (P = .002). Taste aversion was a strongly age-dependent barrier for initiation (P < .001) and continuation (P < .002), with older children over 6 years of age reporting it as a very significant barrier (P < .001). Boredom was reported as a concern for specific allergens such as peanut, egg, sesame, and hazelnuts (P < .05), emphasizing the need for diverse food options. Notably, 59.9% of respondents mixed OIT foods with sweet items. Despite these dietary concerns, dietitians were underutilized, with only 9.5% of respondents having seen a dietitian and the majority finding dietitian support helpful with greater certainty about the exact dose (P < .001).

CONCLUSIONS

Taste aversion and anxiety represent primary patient-related barriers to OIT. Taste aversion was highly age dependent, with older patients being more affected. Dietitians and psychology support were underutilized, representing a critical target to improve adherence and OIT success.

Comprehensive Diagnosis, Management, and Treatment of Sesame Allergy

Sesame allergy prevalence varies regionally and by age, in the range of 0.1% to 0.9%. Reactions can be severe and potentially fatal. Resolution rates are in the range of 20% to 50%. The diagnosis requires a careful history and the use of tests, such as skin prick tests and serum sesame-specific IgE. The availability of serum IgE testing for the sesame protein Ses i 1 has improved diagnostic accuracy. The emerging potential for sesame basophil activation tests and additional new tests will likely improve diagnosis in coming years, further reducing the need for diagnostic oral food challenges. Although sesame proteins share homology with those in many foods, clinically relevant cross-reactivity appears uncommon. Nevertheless, sesame is a prominent allergen for those with multiple food allergies. Management may include strict avoidance, but sesame products vary dramatically in protein content. Many people with sesame allergy tolerate forms that are low in protein, such as scattered seeds, rather than sesame paste that is protein-dense. Thus, options in the approach to avoidance are possible. Studies suggest that sesame oral immunotherapy may be safe and effective, and this and additional treatment options are emerging. Here, we review the current comprehensive diagnosis, management, and treatment for sesame allergy.

Feast for thought: A comprehensive review of food allergy 2021-2023

A review of the latest publications in food allergy over the past couple of years confirmed that food allergy is a major public health concern, affecting about 8% of children and 10% of adults in developed countries. The prevalence of food allergy varies around the world, with the increase being driven mainly by environmental factors, possibly together with genetic susceptibility to environmental changes. A precise diagnosis of food allergy is extremely important. Both new tests (eg, the basophil activation test) and improved optimization of information provided by existing tests (eg, the skin prick test and measurement of specific IgE level) can contribute to improving the accuracy and patients' comfort of food allergy diagnosis. Understanding the underlying immune mechanisms is fundamental to designing allergen-specific treatments that can be safe and effective in the long term. New discoveries of the immune response to food allergens, including T-cell and B-cell responses, have emerged. Novel therapeutic approaches are being trialed at various stages of development as attempts to allow for more active intervention to treat food allergy. Prevention is key to reducing the increase in prevalence. Early introduction of allergenic foods seems to be the most effective intervention, but others are being studied, and will, it is hoped, lead to modification of the epidemiologic trajectory of food allergy over time.

Epidemiology and the Growing Epidemic of Food Allergy in Children and Adults Across the Globe

PURPOSE OF REVIEW

Food allergies are immune-mediated, complex disorders, which are the source of increasing health concern worldwide. The goal of this review is to present an updated summary of the food allergy (FA) burden among children and adults across different populations, focusing on research from the past 5 years.

RECENT FINDINGS

FAs impact a growing number of global residents-particularly those residing in higher-income, industrialized regions. Moreover, growing epidemiologic evidence suggests that the population health burden of non-IgE-mediated FAs, such as food protein-induced enterocolitis syndrome, may also be higher than previously reported. FA is a complex trait that impacts infants, children, as well as adults across the globe. The population health burden of both IgE- and non-IgE-mediated FAs is likely to grow in the absence of rapid advances and widespread implementation of effective FA prevention and treatment interventions. Systematic epidemiological research initiatives are needed, both nationally and globally, to better understand and reduce the burden of these allergic diseases.

Psychosocial Impact of Food Allergy on Children and Adults and Practical Interventions

PURPOSE OF REVIEW

IgE- and non-IgE-mediated food allergies are increasing in prevalence in children and adults worldwide. A food allergy diagnosis can be associated with a sense of overwhelm and stress and commonly has a negative impact on quality of life.

RECENT FINDINGS

While there is an increased recognition of the psychosocial effects of food allergy, the current research reflects the experience of mostly White, well-educated wealthier populations. Some studies have now explored the psychosocial impact among other populations; however, further study is needed. It is important that physicians and allied health professionals screen for the potentially negative psychosocial effects of food allergy and provide education to promote safety and self-efficacy at each visit; however, time may be a limiting factor. Numerous validated questionnaires are now available to help assess the psychosocial impact of food allergies. Allergy-friendly foods are typically more expensive, and thus, it is imperative that physicians screen for food insecurity as well. Educational resources should be offered regarding living well with food allergies at each visit. For patients and families experiencing anxiety or food allergy burden that is difficult to manage, referral to a mental health provider should be considered. Resources regarding programs to help accessing safe foods should also be available. Further research is needed among diverse populations focusing on interventions to best support patients and families with food allergy.

Safety and effectiveness of the Canadian food ladders for children with IgE-mediated food allergies to cow's milk and/or egg

BACKGROUND

Food ladders are tools designed to facilitate home-based dietary advancement in children with food allergies through stepwise exposures to increasingly allergenic forms of milk and egg. Several studies have now documented safety and efficacy of food ladders. In 2021, we published a Canadian adaptation of the previously existing milk and egg ladders originating in Europe using foods more readily available/consumed in Canada. Our study adds to the growing body of evidence supporting food ladder use and provides safety and effectiveness data for our Canadian adaptation of the milk and egg ladders.

METHODS

Surveys were distributed to families of children using the Canadian Milk Ladder and/or the Canadian Egg Ladder at baseline, with follow up surveys at 3 months, 6 months, and 12 months. Data were analyzed using REDCap and descriptive and inferential statistics are presented.

RESULTS

One hundred and nine participants were started on milk/egg ladders between September 2020 and June 2022. 53 participants responded to follow up surveys. Only 2 of 53 (3.8%) participants reported receiving epinephrine during the study. Severe grade 4 reactions (defined according to the modified World Allergy Organization grading system) were not reported by any participants. Minor cutaneous adverse reactions were common, with about 71% (n = 10/14) of respondents reporting cutaneous adverse reactions by 1 year of food ladder use. An increasing proportion of participants could tolerate most foods from steps 2-4 foods after 3, 6, and 12 months of the food ladder compared to baseline.

CONCLUSION

The Canadian food ladders are safe tools for children with cow's milk and/or egg allergies, and participants tolerated a larger range of foods with food ladder use compared to baseline.

A Survey of Canadian Dietitians on Identification of Infants at High Risk of Food Allergy and Frequency of Allergenic Food Consumption

Purpose: To assess knowledge of Canadian dietitians on the topics of food allergy and food allergy prevention guidelines, including introduction of allergenic solids to infants at risk of food allergy.Methods: An online survey was distributed via email listservs targeting Canadian dietitians.Results: In total, 144 of 261 dietitians completed the survey (60.5%). Respondents recommend introduction of peanut (89.5%) and allergenic solids (91.2%) within the recommended age of 4-6 months for infants at high risk of food allergy, but only 26.2% recommend offering peanut three times per week once it has been introduced. In identifying what constitutes an infant at high risk of developing peanut allergy, dietitians expressed lower comfort levels and lower number of correct responses.Conclusions: Dietitians demonstrated they are up to date regarding the timing of introduction of allergenic solids, but not the frequency of consumption once introduced, for infants at high risk of food allergy. They also expressed low comfort level identifying risk factors for peanut allergy. There are opportunities for further education of dietitians, as well as potential to further utilize dietitian services for the benefit of patients with food allergy or who are at risk for food allergy.

Prevalence of self-reported food allergy in Tunisia: General trends and probabilistic modeling

Background

Food allergy (FA) has become a major public health concern affecting millions of children and adults worldwide. In Tunisia, published data on FA are scarce.

Methods

This study, was intended to fill the gap and estimate the frequency of allergy to different foods in the Sfax region, Tunisia, within self-reported FA. One hundred twenty-five (125) children (56% males, 1-17 years old), and 306 adults (17% males, 18-70 years old) were interviewed using a bilingual questionnaire.

Results

The number of self-reported food allergens in this sample was 105; allergens were clustered in 8 foods: fruits, seafood, eggs, milk and dairy, cereals, nuts, vegetables, and peanuts. Cutaneous reactions were the most frequent symptoms, in both children and adults. About 40% of children and 30% of adults had a family history of FA. About 81% of adults and 38% of children are allergic to at least 1 non-food allergen. The most prevalent food allergen was the fruit group in both adults and children, followed by seafood. Most food allergies were mutually exclusive and 90% of individuals have a single FA. The relationship between self-declared FA was modeled using a Bayesian network graphical model in order to estimate conditional probabilities of each FA when other FA is present.

Conclusions

Our findings suggest that the prevalence of self-reported FA in Tunisia depends on dietary habits and food availability since the most frequent allergens are from foods that are highly consumed by the Tunisian population.

"Vegan" and "plant-based" claims: risk implications for milk- and egg-allergic consumers in Canada

The market share of foods carrying labels suggesting absence of animal ingredients has significantly increased in recent years. The purpose of this study was to document the purchasing behaviour of egg- or milk-allergic consumers vis-à-vis food marketed as "vegan" and "plant-based", and to evaluate the associated allergenic risk. A survey was conducted among egg- and milk-allergic consumers and revealed that 86% (margin of error 5.4%; confidence level 95%) would buy "vegan" products, indicating this label may be perceived as a substitute for "free from milk and eggs". To assess the risk posed by these products, 87 prepackaged foods with "vegan" and/or "plant-based" claims purchased in Quebec were tested for milk proteins, and 64 for egg proteins. Overall, 5.7% and 0% occurrence of milk and egg proteins, respectively, were observed, suggesting that the analysed prepackaged foods carrying "vegan" and/or "plant-based" labels pose little risk to egg- or milk-allergic consumers. However, this is likely due to allergen management practices applied by the Canadian manufacturers of the products tested, and should not be attributed to the use of "vegan" or similar labels. Enhanced regulatory requirements for the use of these labels, and an education campaign on their meaning with respect to allergy-related risks, are necessary to better inform and protect egg- and milk-allergic consumers.

The potential of dietary nanoparticles to enhance allergenicity of milk proteins: an in vitro investigation

In recent years, the popularity of dietary nanoparticles (NPs) in the food industry as additives has raised concerns because of the lack of knowledge about potential adverse health outcomes ensuing from the interactions of NPs with components of the food matrix and gastrointestinal system. In this study, we used a transwell culture system that consisted of human colorectal adenocarcinoma (Caco-2) cells in the apical insert and Laboratory of Allergic Diseases 2 mast cells in the basal compartment to study the effect of NPs on milk allergen delivery across the epithelial layer, mast cell responses and signaling between epithelial and mast cells in allergenic inflammation. A library of dietary particles (silicon dioxide NPs, titanium dioxide NPs and silver NPs) that varied in particle size, surface chemistry and crystal structures with or without pre-exposure to milk was used in this investigation. Milk-interacted particles were found to acquire surface corona and increased the bioavailability of milk allergens (casein and β-lactoglobulin) across the intestinal epithelial layer. The signaling between epithelial cells and mast cells resulted in significant changes in the early phase and late-phase activation of the mast cells. This study suggested that antigen challenge in mast cells with the presence of dietary NPs may cause the transition of allergic responses from an immunoglobulin E (IgE)-dependent mechanism to a mixed mechanism (both IgE-dependent and IgE-independent mechanisms).

Parental perceptions of a novel subsidy program to address the financial burden of milk allergy: a qualitative study

BACKGROUND

Approximately 6-7% of Canadian children have food allergy. These families face substantial burdens due to the additional costs incurred purchasing allergy-friendly products necessary for management compared to families without food allergies. In the year prior to the COVID-19 pandemic, these costs were equivalent to an average of $200 monthly compared to families without food allergy. As food prices continue to rise, rates of food insecurity also increase, disproportionately affecting households with food allergy who have limited choices at food banks.

METHODS

Families living or working in Winnipeg, Canada with an annual net income of about $70,000 or less the year prior to recruitment and a child under the age of 6 years old with a physician diagnosed milk allergy were recruited between January and February 2022. Participating families received bi-weekly home deliveries for six months, from March to August 2022, of subsidy kits containing ~$50 worth of milk allergy-friendly products. Semi-structured interviews, completed ± 2 weeks from the final delivery, were audio-recorded, transcribed verbatim, and analyzed thematically.

RESULTS

Eight interviews, averaging 32 min (range 22-54 min), were completed with mothers from all different families. On average, mothers were 29.88 ± 4.39 years old and children were 2.06 ± 1.32 years old. All children reported allergies in addition to milk. Based on the data from these interviews, we identified 3 themes: food allergy causes substantial burden for families, "I have to get his allergy-friendly food first before getting to my basic needs", and perceived emotional and financial benefits of a milk allergy-friendly food subsidy program.

CONCLUSIONS

This study, along with previous research, suggests that there is a need for assistance for families managing milk allergies. It also provides important information to inform development of programs which can address these financial challenges. Our in-kind food subsidy was perceived as having a positive impact on food costs and stress associated with food allergy management, however, parents identified a need for more variety in the food packages. Future programs should strive to incorporate a greater variety of products to address this limitation.

Food Allergy Education and Management in Early Learning and Childcare Centres: A Scoping Review on Current Practices and Gaps

Anaphylaxis has occurred in preschools/schools yet there are no consistent food allergy (FA) management practices in early learning and childcare centres (ELCC) across jurisdictions. Presently, there are no reviews that have synthesized FA-related knowledge and management practices within ELCC. We aimed to perform a scoping review of FA management in ELCC, and report on perceived gaps or barriers. A PRISMA-ScR-guided search was conducted for North American, European and Australian articles in English/French in the OVID-MedLine, Scopus, and PsycInfo databases. Two independent reviewers screened the titles/abstracts of 2010 articles and full-text screened 77 articles; 15 of which were specifically related to ELCC. If the two reviewers could not agree to the relevance of a given study, a third reviewer provided guidance. This third reviewer also screened French articles. Thematic and descriptive reports of the studies were presented. We reported solely on pre-Coronavirus Disease pandemic ELCC studies. We included ten articles in this review, which provide evidence that ELCC staff have variable baseline knowledge, comprehension, experience, and practices in place to manage FA. ELCC staff also have limited FA-related training and experience regarding administration of epinephrine auto-injectors (EAI). Emergency Anaphylaxis Plans (EAP) were described in four studies. One study reported the parental influence on the site's food purchasing and FA management. Three studies provided educational interventions, which demonstrated increased and sustained FA-related knowledge and confidence post-intervention. Participants deemed the training beneficial and desired annual training and more FA resources to be available. Across jurisdictions, ELCC staff have provided care and administered EAI in emergencies, but training remained variable. Communication and care planning amongst ELCC staff, and parents, is crucial. Annual education, available EAI and EAPs are tools necessary for effectively managing emergencies.

Assessment of multiple-opinion referrals and consults at the BC Children's Hospital Allergy Clinic

BACKGROUND

Allergic disease is on the rise. Waitlists for specialists are long, and many referred patients have already received prior allergic assessment, either by a certified Allergist, Primary Care Provider, or other Specialist. It is important to understand the prevalence and motivating factors for multiple-opinion referrals, to deliver timely assessment for patients with allergic disease.

METHODS

A retrospective chart review of demographic information, number of previous consultations, and motivation for new consults and multiple-opinion referrals, of pediatric patients aged 8 months-17 years to BC Children's Hospital Allergy Clinic from September 1, 2016-August 31, 2017, was performed. Referral data including reason for referral or multiple-opinion, primary allergic concerns, and others, from referral forms and consult notes were accessed through local Electronic Medical Records and subsequently analyzed for trends in categorical variables to assess the rationale for and impact of multiple-opinion referrals to our clinic.

RESULTS

Of 1029 new referrals received, 210 (20.4%) were multiple-opinion referrals. Food allergy was the predominant allergic concern prompting further opinion (75.7%). The main rationale for seeking further opinions was wanting an assessment by a certified allergist in cases where prior consultation was performed by non-allergist specialist, primary care provider, or alternative health care provider. Of second-opinion referrals generated, 70 (33.3%) initial consultations were performed by an Allergist, whereas 140 (66.7%) were performed by a non-allergist.

CONCLUSIONS

Many new consults at the BCCH Allergy Clinic are multiple-opinion assessments, contributing to long waitlists. Advocacy at the systems level through standardized referral guidelines, centralized triaging systems, and stronger support for Primary Care Providers is needed to provide better access in Canada for children needing a specialized Allergist. Trial registration UBC/BCCH Research Ethics Board.

An online, peer-mentored food allergy education program improves children's and parents' confidence

BACKGROUND

Children with food allergy, and their families experience substantial burdens because of efforts necessary to minimize the risk of anaphylaxis. To this end, peer-to-peer education is paramount. Food Allergy Canada offers an online, peer-to-peer mentoring program. However, the impact of this program has not previously been formally evaluated.

OBJECTIVE

To determine if Allergy Pals, an online, peer-to-peer mentoring program, for children aged 7-11 years, increased child and parental food allergy competency, and confidence. Our secondary aim was to qualitatively describe the experiences of the program.

METHODS

From May 2020-May 2021, children and their parents were invited to participate in an online, anonymous survey about Allergy Pals, at pre-program, and post-program. Primary outcomes, which were described and compared using chi2 or t-tests, as appropriate for the respective variables, included food allergy competence (epinephrine carriage, signs and symptoms of anaphylaxis) and food allergy confidence (e.g. comfort asking other for food allergy-related support). Secondary outcomes included child and parent perceptions of the program, which were analysed thematically.

RESULTS

Overall, 17 children completed the pre-program, and 11 completed the post-program survey. Corresponding numbers for parents were 25 and 23. Food allergy competence was high pre-program, and remained so post-program. Food allergy confidence improved from pre-program to post-program. E.g. Children tended to feel less left out (5/12, 41.7%; 3/10; 30.0%, respectively), a finding that was reflected also in parents' scores. Themes identified for child and parent perceptions further supported improved food allergy confidence.

CONCLUSION

Although food allergy competence was high pre-program, Allergy Pals improved food allergy confidence.

The epidemiology of food allergy in adults

The prevalence and awareness of food allergy (FA) among US adults is arguably at a historical high, both with respect to primary immunoglobulin E-mediated food hypersensitivity and other food-triggered conditions that operate through a variety of immunologic mechanisms (eg, pollen-FA syndrome, alpha-gal syndrome, food protein-induced enterocolitis syndrome, eosinophilic esophagitis). Worryingly, not only are many adults retaining childhood-onset food allergies as they age into adulthood, it seems that many adults are experiencing adult-onset allergies to previously tolerated foods, with correspondingly adverse physical, and psychological health impacts. Consequently, this review aims to summarize what is currently known about the epidemiology and population-level burden of FA among adult populations in North America and around the globe. This article also provides insights into the natural history of these conditions and what we need to know as we look to the future to support effective care and prevent FA.

Temporal trends in anaphylaxis ED visits over the last decade and the effect of COVID-19 pandemic on these trends

BACKGROUND

Anaphylaxis is an acute systemic and potentially fatal allergic reaction. We evaluated trends in yearly rates of anaphylaxis in a pediatric Emergency Department (ED) in Montreal, Canada.

METHODS

A prospective and retrospective recruitment process was used to find families of children who had presented with anaphylaxis at the Montreal Children's Hospital between April 2011 and April 2021. Using a uniform recruitment form, data were collected. Anaphylaxis patterns were compared to clinical triggers using descriptive analysis.

RESULTS

Among 830,382 ED visits during the study period, 2726 (26% recruited prospectively) presented with anaphylaxis. The median age was 6 years (IQR: 0.2, 12.00), and 58.7% were males. The relative frequency of anaphylaxis cases doubled between 2011-2015, from 0.22% (95% CI, 0.19, 0.26) to 0.42 March 2020, the total absolute number of anaphylaxis cases and relative frequency declined by 24 cases per month (p < 0.05) and by 0.5% of ED visits (p < 0.05).

CONCLUSIONS

The rate of anaphylaxis has changed over the years, representing modifications in food introduction strategies or lifestyle changes. The decrease in the frequency of anaphylaxis presenting to the ED during the COVID pandemic may reflect decreased accidental exposures with reduced social gatherings, closed school, and reluctance to present to ED.

Geographical discrepancy in oral food challenge utilization based on Canadian billing data

BACKGROUND

Oral food challenges (OFC) confer the highest sensitivity and specificity in diagnosis; however, uptake has been variable across clinical settings. Numerous barriers were identified in literature from inadequate training to resource access. OFC utilization patterns using billing data have not been previously studied.

OBJECTIVE

The objective of this study is to explore the geographic differences in utilization of OFCs across Ontario and Québec using anonymized billing data from 2013 to 2017.

METHODS

Anonymized OFC billing data were obtained between 2013 and 2017 from Ontario Health Insurance Plan (OHIP) and Régie de l'Assurance Maladie du Québec (RAMQ). The number of OFCs was extracted by location, billings, and physician demographics for clinic and hospital-based challenges.

RESULTS

Over the period studied, the number of OFCs increased by 92% and 85% in Ontario clinics and Québec hospitals, respectively. For Ontario hospitals, the number of OFCs increased by 194%. While Québec performed exclusively hospital-based OFCs, after controlling for the population, the number of OFCs per 100,000 residents annually were similar to Ontario at 50 and 49 OFCs, respectively. The number of OFCs varied across the regions studied with an annual rate reaching up to 156 OFCs per 100,000 residents in urban regions and as low as 0.1 in regions furthest from city centers.

CONCLUSION

OFC utilization has steadily increased over the last decade. There has been marked geographical discrepancies in OFC utilization which could be driven by the location of allergists and heterogeneity in their practices. More research is needed to identify barriers and propose solutions to them.

Ultra-processed foods and allergic symptoms among children and adults in the United States: A population-based analysis of NHANES 2005-2006

Design

There is a strong correlation between dietary intake and allergic diseases. Ultra-processed foods (UPFs) are gradually becoming dominant worldwide and causing health problems for children and adults. We hope to determine whether links exist between UPFs and allergic symptoms.

Methods

We investigated data from 2,736 children (16-19 years) and 4,256 adults (≥20 years) from the National Health and Nutritional Examination Survey (NHANES) 2005-2006. The associations between the mean UPFs contribution to total energy intake and all allergic symptoms (IgE, current asthma, allergy, rash, sneeze, wheeze, eczema, and hay fever) were estimated by weighted multivariate logistic regression.

Results

Logistic regression analysis showed UFPs were negatively associated with IgE levels in children. Those with higher quartiles had a reduced risk from 16% (OR, 0.84, 95%CI, 0.55 to 1.28) to 34% (OR, 0.66, 95%CI, 0.49 to 0.89), p for trend = 0.006. UPFs were also positively related to current asthma in children with an increased risk of 11% (OR, 1.11, 95%CI, 0.79 to 1.56) to 76% (OR, 1.76, 95%CI, 1.10 to 2.82), p for trend = 0.0393. UPFs were also associated with eczema in girls. But there was no association observed between UPFs and allergic symptoms in adults.

Conclusion

Our results suggested that UPFs assessed by the NOVA system were associated with IgE, current asthma in children, and eczema in girls. These results further support the need to test the association of modern dietary patterns with allergic symptoms.

Sesame-induced anaphylaxis in pediatric patients from the cross-Canada anaphylaxis registry

BACKGROUND

Sesame can cause severe allergic reactions and is a priority allergen in Canada.

OBJECTIVE

To assess clinical characteristics and management of pediatric sesame-induced anaphylaxis and identify factors associated with epinephrine treatment.

METHODS

Between 2011 and 2021, children with sesame-induced anaphylaxis presenting to 7 emergency departments (ED) in 4 Canadian provinces and 1 regional emergency medical service were enrolled in the Cross-Canada Anaphylaxis Registry. Standardized recruitment forms provided data on symptoms, severity, triggers, and management. Multivariate logistic regression evaluated associations with epinephrine treatment pre-ED and multiple epinephrine dosages.

RESULTS

Of all food-induced anaphylactic reactions (n = 3279 children), sesame accounted for 4.0% (n = 130 children), of which 61.5% were boys, and the average (SD) age was 5.0 (4.9) years. Hummus containing sesame paste triggered 58.8% of reactions. In the pre-ED setting, 32.3% received epinephrine, and it was more likely to be used in boys (adjusted odds ratio [aOR], 1.27; 95% confidence interval [CI], 1.08-1.50) and those with a known food allergy (aOR, 1.36; 95% CI, 1.11-1.68]). In the ED, 47.7% of cases received epinephrine, with older children more likely to receive multiple epinephrine doses (aOR, 1.00; 95% CI, 1.00-1.02).

CONCLUSION

In Canada, hummus is the major trigger of sesame-induced anaphylaxis. Knowledge translation focused on prompt epinephrine use and product-labeling policies are required to limit sesame reactions in communities.

Changes in food-related costs during the COVID-19 pandemic among families managing food allergy

Background

The COVID-19 pandemic has affected the supply, cost, and demand for certain foods, but it is not clear how these changes have affected food-allergic households.

Objective

To describe the changes in food-related costs that have followed COVID-19, as reported by higher- and lower-income households with a food-allergic member.

Methods

Between May 1-June 30, 2020, Canadian households, with at least one food-allergic member, completed an online survey on food shopping and preparation habits before and during the COVID-19 pandemic. The sample was divided into binary groups, either higher or lower than the sample median income. Data were analyzed using descriptive statistics and multiple regression.

Results

The sample was comprised of 102 participants (i.e., 51/ income group). The three most common food allergies amongst both groups were peanuts, tree nuts and milk. Since the start of the pandemic, both groups reported greater monthly direct grocery costs, although costs amongst the higher-income group were twice as high as the lower-income group ($212.86 vs. $98.89, respectively). Indirect food preparation costs were similarly elevated. Higher-income households with food procurement difficulties reported increased indirect shopping costs following the outbreak of COVID-19, whereas those without such difficulties reported decreased costs. Lower-income households with allergies to milk, wheat, or eggs (i.e., staple allergy) experienced a larger change in indirect food preparation costs following the outbreak of COVID-19 relative to those with other food allergies ($244.58 vs. –$20.28, respectively; p = 0.03).

Conclusion

Both higher and lower income households with food allergy reported greater direct food costs and indirect food preparation costs following the COVID-19. Households with staple allergy and those with difficulties finding their typical food items were particularly affected.

The need for a food allergy educator program for allied healthcare professionals in Canada

Owing to a collaborative approach to patient care, and a paucity of allergists in Canada, there is a need to develop a food allergy educational program for allied health care professionals in Canada. Such programs already exist in the United States and Britain. Herein, we describe the outcomes of recent conference proceedings to inform the educational needs for such a program. As part of the 76th Annual Meeting of the Canadian Society of Allergy and Clinical Immunology (CSACI), held virtually due to the COVID-19 pandemic, we hosted a virtual workshop on the need for a food allergy educator program for Canadian allied health professionals. This workshop was co-developed with the CSACI and an industry partner, and featured allergy specialist dietitians. Attendance was open to all conference delegates, and to allied health professionals. As part of the registration process, registrants posed diverse food allergy-related questions, ranging from how to use an epinephrine autoinjector, to daily management and, how to cure food allergy. A national food allergy educator program will empower both allergy and non-allergy specialist healthcare professionals to appropriately counsel patients. This virtually-delivered program will begin to close a gap in healthcare access resulting from the geographic size of Canada, as it will enhance allied healthcare providers’ confidence to provide evidence-based food allergy care appropriately for those with food allergy.

Elementary School Teachers’ Perceptions of COVID-19-Related Restrictions on Food Allergy Management

(1) Background: Approximately 7% of Canadian children live with a food allergy (FA). Pre-COVID-19, ~20% of anaphylactic reactions occurred in schools. Yet, teachers reported poor FA-related knowledge, and experiences during the COVID-19 pandemic are not well-studied. Additionally, teachers’ management approaches vary widely. We aimed to describe elementary school teachers’ perceptions about FA management during the COVID-19 pandemic; (2) Methods: Using a semi-structured interview guide, English-speaking elementary school teachers in Winnipeg, Canada were interviewed virtually. Interviews were audio-recorded and transcribed verbatim. Data were analysed thematically; (3) Results: Most teachers were female and taught in public schools. Two themes were identified. Theme 1, COVID-19 restrictions made mealtimes more manageable, capturing the positive impacts of pandemic restrictions such as seating arrangements and enhanced cleaning. Limited lunchtime supervision prompted some teachers to assume this role. Theme 2, Food allergy management was indirectly adapted to fit changing COVID-19 restrictions, describing how changing restrictions influenced FA-related practices. FA training was offered virtually with less nursing support. Class cohorts and remote learning decreased teachers’ perceived risk and FA-related management responsibility; (4) Conclusions: COVID-19-related practices were perceived as positively influencing in-school FA management, although unintended consequences, such as increased supervisory roles for teachers and reduced nursing support, were described.

An Adjuvant-Free Mouse Model Using Skin Sensitization Without Tape-Stripping Followed by Oral Elicitation of Anaphylaxis: A Novel Pre-Clinical Tool for Testing Intrinsic Wheat Allergenicity

Wheat is a major food allergen per the regulatory bodies of various nations. Hypersensitivity reactions to wheat have been steadily increasing for reasons that are not completely understood. Wheat-allergy models typically use adjuvants to induce sensitization to wheat proteins followed by an intraperitoneal challenge to elicit anaphylaxis. Although these models are very useful, they lack the ability to reveal the intrinsic allergenicity potential of wheat. To improve the mouse model of wheat allergy, we tested the hypothesis that repeated skin application of salt-soluble protein extract (SSPE) from durum wheat will clinically sensitize the mice to oral anaphylaxis to SSPE. Balb/c mice were bred and maintained on a plant-protein-free diet and used in the experiments. Adult female mice were exposed to SSPE once a week for 9 weeks via a solution on intact skin. Sensitization was measured by SSPE-specific IgE (sIgE) antibody and total IgE (tIgE) levels. Oral anaphylaxis was quantified by hypothermic shock response (HSR), and mucosal mast cell response (MMCR) was quantified by measuring MMCP-1 after oral challenge. Using single mouse data, correlation analyses were performed to determine the relationship among the allergenicity readouts. Spleen cytokines were quantified using a protein microarray method. Our results show that (i) repeated skin exposures to SSPE elicited robust increases in the sIgE and tIgE levels; (ii) skin exposure to SSPE was sufficient to sensitize mice for oral anaphylaxis and MMCR; (iii) both HSR and MMCR showed a strong correlation with each other, as well as with sIgE, and a modest correlation with tIgE levels; (iv) selected Th2/Th17/Th1 cytokines were elevated in skin-sensitized mice; and (v) oral allergen-challenged mice showed selective elevation of IL-6 and a panel of chemokines compared to saline-challenged mice. Together, we report the development and characterization of a novel adjuvant-free wheat-allergy mouse model that uses skin sensitization without tape-stripping followed by oral elicitation of anaphylaxis. Furthermore, validation of quantifiable wheat allergenicity readouts makes this model particularly suitable as a pre-clinical testing tool to assess the intrinsic sensitization/oral-anaphylaxis elicitation potential of novel wheat proteins (e.g., processed wheat) and to develop hypo/non-allergenic wheat products.

Tree Nut-Induced Anaphylaxis in Canadian Emergency Departments: Rate, Clinical Characteristics and Management

BACKGROUND

Data are sparce regarding tree nut-induced anaphylaxis (TNA).

OBJECTIVE

We aimed to characterize rate, clinical characteristics, and management of TNA in children (0-17 years old) across Canada, and assess factors associated with severe reactions and epinephrine use.

METHODS

Between April 2011 and May 2020, data were collected on children presenting to five emergency departments (EDs) in Canada. Multivariate logistic analysis was used to evaluate factors associated with severe reactions (stridor, cyanosis, circulatory collapse, or hypoxia) and epinephrine use.

RESULTS

Among 3096 cases of anaphylaxis, 540 (17%) were induced by tree nut. The median age was 5.2 years [Interquartile range (IQR): 2.5-9.5] and 65.4% were males. Among all reactions, 7.0% were severe. The major tree nuts accounting for anaphylaxis were cashew (32.8%), hazelnut (20.0%) and walnut (11.5%). Cashew-induced anaphylaxis was more common in British Columbia [14.0% difference (95% CI, 1.6%-27.6%)] versus Ontario and Quebec, whereas pistachio-induced anaphylaxis was more common in Ontario and Quebec [6.3% difference (95% CI, 0.5%-12.2%)]. Pre-hospital and ED intramuscular (IM) epinephrine administration was documented in only 35.2% and 52.4% of cases, respectively. Severe reactions were more likely among males [adjusted Odds Ratio (aOR) 1.05 (95% CI, 1.01-1.10)] older children [aOR 1.00 (95% CI, 1.00-1.01)], and in reactions triggered by macadamia [aOR 1.27 (95% CI, 1.03-1.57)].

CONCLUSION

Different TNA patterns in Canada may be due to differences in lifestyle (higher prevalence of Asian ethnicity in British Columbia versus Arabic ethnicity in Ontario and Quebec). IM epinephrine underutilization urges for EAI stocking in schools and restaurants, patient education, and consistent policies across Canada.

It takes a village: perceptions of Winnipeg parents, students, teachers and school staff regarding the impact of food allergy on school-age students and their families

Background

The entire school community contributes to the safety of students with food allergy. We sought to determine the food allergy perceptions and education needs of parents, students and school staff, with the goal of enhancing food allergy education in schools.

Methods

With ethics approval from the University of Manitoba and participating school divisions, elementary school principals emailed SurveyMonkey^® Questionnaire Links to their parent/caregiver contact list and school staff. We compared anonymous responses of parents of children with and without food allergy, students with and without food allergy, and parents and school staff using chi-squared tests.

Results

Participants included 561 parents of school-age children (ages 7–12 years, 19% with food allergy), 61 students (23% with food allergy), and 203 school staff (62% teachers, 88% with experience managing food allergies in the classroom). Parents of children with and without food allergy considered food allergy when sending food to school (98% vs. 96%, p = 0.39). More parents of children with food allergy thought that greater information and awareness about food allergy was needed (74% vs. 44%, p < 0.0001). Students with food allergy were most interested (100%) in having other students learn not to bully and how to help during a reaction. Students without food allergy were most interested in learning how to prevent a reaction (70%). Fewer parents than school staff thought that food allergies in the classroom impacted teachers’ time (2.1% vs. 21%, p < 0.0001) and that teachers knew how to treat allergic reactions to foods (34% vs. 94%, p < 0.0001). More parents than school staff thought that banning foods from classrooms kept allergic students safe (65% vs. 34%, p = 0.006) and that having a Food Allergy Educator speak at school would be helpful (99% vs. 67%, p < 0.0001).

Conclusions

Food allergy education is necessary for the entire school community and should include parents of school-aged children with and without food allergy, students with and without food allergy, and teachers and school staff. These members of the school community recognized their own and others’ needs for increased food allergy education and awareness in the school setting.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13223-022-00682-2.

Spent fowl as a source of unintentional egg proteins exposure in Canadian food products

The occurrence of egg proteins in products containing spent fowl manufactured under current practices was studied to assess the risk these food products may pose to egg-allergic consumers and to determine if Precautionary Allergen Labelling (PAL) was recommended. Spent fowl slaughtering and processing operations in 2 Canadian facilities were observed. Raw hen pieces (n = 134), coming from 2 facilities, and intermediate and processed products containing spent fowl (n = 57), coming from one facility, were analyzed using ELISA. All samples tested positive for egg proteins. Raw pieces were tested using a qualitative method (i.e., swabbing); estimated egg proteins concentrations suggest the presence of highly contaminated samples (>600 mg/kg in 2 hen wing samples). Swabbing was found to be efficient for rapid detection of eggs in raw hen pieces, but not for quantification. A comparison between swab and grind results showed that egg proteins concentration is underestimated by at least a factor 2 for whole carcasses and a factor 10 for breast, wings and drumsticks, when using the swab protocol. For intermediate and processed products, quantitative measurements indicate that egg protein levels were below 16 mg/kg. Additionally, 88 water samples from chiller tanks were analyzed and indicate that this step could be the cause of the global contamination observed with an increase in egg protein concentrations overtime during the production schedule. As egg contamination is not adequately controlled under the current good production practices, the use of PAL would be recommended for raw spent fowl products.

Seafood-induced anaphylaxis in children presenting to Canadian emergency departments: Rates, clinical presentation, and management

BACKGROUND

There is a lack of data on seafood-induced anaphylaxis in children in Canada.

OBJECTIVE

To evaluate the rate, clinical features, and management of seafood-induced anaphylaxis in children presenting to emergency departments across Canada.

METHODS

Children with anaphylaxis were recruited at 6 emergency departments between 2011 and 2020 as part of the Cross-Canada Anaphylaxis REgistry. A standardized form documenting symptoms, triggers, comorbidities, and management was used to collect data.

RESULTS

There were 75 fish-induced and 71 shellfish-induced cases of suspected anaphylaxis, most of which were caused by salmon and shrimp, respectively. Mucocutaneous symptoms were most common, whereas respiratory symptoms were associated with patients with fish-induced reactions who have comorbid asthma (adjusted odds ratio [aOR], 1.18; 95% confidence interval [CI], 1.02-1.36). Prehospital epinephrine was underused (<35%), whereas in-hospital epinephrine was given to less than 60% of the patients. Among those with a known fish or shellfish allergy, prehospital epinephrine use was associated with known asthma (aOR 1.39 [95% CI, 1.05-1.84] and aOR 1.25 [95% CI, 1.02-1.54], respectively). Among children who were assessed by either skin test or specific immunoglobulin E, 36 patients (76.6%) with suspected fish-induced anaphylaxis and 19 patients (51.4%) with suspected shellfish-induced anaphylaxis tested positive.

CONCLUSION

Prehospital epinephrine is underused in the management of seafood-induced anaphylaxis. Among children with known seafood allergy, prehospital epinephrine use is more likely if there is a known asthma comorbidity.

Dietary exposures and allergy prevention in high-risk infants

Infants at high risk for developing a food allergy have either an atopic condition (such as eczema) themselves or an immediate family member with such a condition. Breastfeeding should be promoted and supported regardless of issues pertaining to food allergy prevention, but for infants whose mothers cannot or choose not to breastfeed, using a specific formula (i.e., hydrolyzed formula) is not recommended to prevent food allergies. When cow's milk protein formula has been introduced in an infant's diet, make sure that regular ingestion (as little as 10 mL daily) is maintained to prevent loss of tolerance. For high-risk infants, there is compelling evidence that introducing allergenic foods early-at around 6 months, but not before 4 months of age-can prevent common food allergies, and allergies to peanut and egg in particular. Once an allergenic food has been introduced, regular ingestion (e.g., a few times a week) is important to maintain tolerance. Common allergenic foods can be introduced without pausing for days between new foods, and the risk for a severe reaction at first exposure in infancy is extremely low. Pre-emptive in-office screening before introducing allergenic foods is not recommended. No recommendations can be made at this time about the role of maternal dietary modification during pregnancy or lactation, or about supplementing with vitamin D, omega 3, or pre- or probiotics as means to prevent food allergy.

Economic burden of food allergy in Canada: Estimating costs and identifying determinants

BACKGROUND

Limited data exist on the economic burden of food allergy (FA).

OBJECTIVE

To assess FA-related direct (healthcare and out-of-pocket) and indirect (lost productivity) costs and their determinants in Canadian children and adults self-reporting FA.

METHODS

FA-individuals self-reporting a convincing history or physician diagnosis were recruited through FA registries, an anaphylaxis registry, and advocacy associations, and electronically surveyed regarding FA-related healthcare use, out-of-pocket expenditures, and time lost from paid and unpaid labor. Direct and indirect costs (2020 Canadian dollars [CAD]) were stratified on severe reaction vs mild, moderate or no reaction, and children vs adults; multivariate regressions assessed the association between costs and sociodemographic and disease characteristics.

RESULTS

Between May 2018 and July 2019, 2692 eligible individuals responded (2189 convincing history and 503 physician diagnosis only); 1020 experienced a severe reaction; 1752 were children. Per FA-individual, annual healthcare, out-of-pocket, and indirect costs were $1267, $2136, and $7950. Those with a severe reaction had higher healthcare and out-of-pocket costs than those with mild, moderate or no reaction. FA-children vs FA-adults had higher healthcare and out-of-pocket costs, and lower indirect costs. Multivariate results showed that lower age, a severe reaction ever, multiple FAs, and fair or poor general health were associated with higher healthcare and out-of-pocket costs. Higher age, lower household education and income, and fair or poor general health were associated with higher indirect costs.

CONCLUSION

The economic burden of FA in Canada is substantial, particularly for those with a severe reaction ever, multiple FAs, and fair or poor general health. It is crucial that those most adversely affected are allocated appropriate resources to support disease management.

The Economic Burden of Food Allergy: What We Know and What We Need to Learn

Purpose of Review

Food allergy management and treatment require dietary modification, are associated with significant burdens, and affect food choices and behaviours. Emerging therapies, such as oral immunotherapy (OIT), provide a glimmer of hope for those living with the condition. Some burdens have received substantial focus, whereas many knowledge gaps on the significance of other impacts, including economic burden, remain.

Recent Findings

Evidence from many countries, but disproportionately from the United States, supports that food allergy carries significant healthcare and societal costs. Early introduction for the prevention of food allergies is theoretically cost-effective, but remains largely undescribed. Unique considerations, such as those to cow’s milk protein allergy, which affects a substantial proportion of infants, and adrenaline autoinjectors, which have a high cost-per-use, require a balance between cost-effectiveness to the healthcare system and adverse outcomes. Household costs have largely been explored in two countries, but owing to different healthcare structures and costs of living, comparisons are difficult, as are generalisations to other countries. Stock epinephrine in schools may present a cost-effective strategy, particularly in economically disadvantaged areas. Costs relating to OIT must be examined within both immediate benefits, such as protection from anaphylaxis, and long-term benefits, such as sustained unresponsiveness.

Summary

Although the absolute costs differ by region/country and type of food allergy, a consistent pattern persists: food allergy is a costly condition, to those who live with it, and the multiple stakeholders with which they interact.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40521-022-00306-5.

Maillard Reaction Induced Changes in Allergenicity of Food

Food allergy is increasing in prevalence, posing aheavier social and financial burden. At present, there is still no widely accepted treatment for it. Methods to reduce or eliminate the allergenicity of trigger foods are urgently needed. Technological processing contributes to producing some hypoallergenic foods. Among the processing methods, the Maillard reaction (MR) is popular because neither special chemical materials nor sophisticated equipment is needed. MR may affect the allergenicity of proteins by disrupting the conformational epitope, disclosing the hidden epitope, masking the linear epitope, and/or forming a new epitope. Changes in the allergenicity of foods after processing are affected by various factors, such as the characteristics of the allergen, the processing parameters, and the processing matrix, and they are therefore variable and difficult to predict. This paper reviews the effects of MR on the allergenicity of each allergen group from common allergenic foods.

Food Allergy Education and Management in Schools: A Scoping Review on Current Practices and Gaps

Currently, no synthesis of in-school policies, practices and teachers and school staff’s food allergy-related knowledge exists. We aimed to conduct a scoping review on in-school food allergy management, and perceived gaps or barriers in these systems. We conducted a PRISMA-ScR-guided search for eligible English or French language articles from North America, Europe, or Australia published in OVID-MedLine, Scopus, and PsycINFO databases. Two reviewers screened 2010 articles’ titles/abstracts, with 77 full-text screened. Reviewers differed by language. Results were reported descriptively and thematically. We included 12 studies. Among teachers and school staff, food allergy experiences, training, and knowledge varied widely. Food allergy experience was reported in 10/12 studies (83.4%); 20.0–88.0% had received previous training (4/10 studies; 40.0%) and 43.0–72.2% never had training (2/10 studies; 20.0%). In-school policies including epinephrine auto-injector (EAI) and emergency anaphylaxis plans (EAP) were described in 5/12 studies (41.7%). Educational interventions (8/12 studies; 66.7%) increased participants’ knowledge, attitudes, beliefs, and confidence to manage food allergy and anaphylaxis vs. baseline. Teachers and school staff have more food allergy-related experiences than training and knowledge to manage emergencies. Mandatory, standardized training including EAI use and evaluation, and the provision of available EAI and EAPs may increase school staff emergency preparedness.

Global patterns in anaphylaxis due to specific foods: A systematic review

BACKGROUND

There are increasing global data relating to prevalence of food allergy and food-induced anaphylaxis; however, this is often based on surrogate measures of sensitization rather than objective symptoms at food challenge. In terms of protecting food-allergic consumers from reactions, to our knowledge, there has been no global survey assessing geographic differences in the proportion of anaphylaxis triggered by specific foods.

OBJECTIVE

We sought to identify common triggers for food-induced anaphylaxis and how these vary from country to country.

METHODS

Systematic review of relevant reports published between January 2010 and November 2020. Results were reported following PRISMA guidelines. Publications were screened and data extracted by 2 independent reviewers, and the risk of bias was assessed.

RESULTS

Sixty-five studies (encompassing 41 countries and all 6 regions as defined by the Food and Agriculture Organization of the United Nations) were included. Significant regional variations in the most common triggers of food anaphylaxis were seen; however, in general, there was good agreement between local legislative requirements for allergen disclosure and the most common allergens for each region or nation.

CONCLUSIONS

Local legislation for allergen disclosure generally reflects those allergens commonly responsible for food anaphylaxis. Cow's milk and crustaceans appear to cause a higher proportion of anaphylaxis compared to peanut in some regions.

Elevated Cow's Milk-Specific IgE Levels Prior to Oral Immunotherapy Decrease the Likelihood of Reaching the Maintenance Dose

BACKGROUND

Food desensitization via oral immunotherapy (OIT) is gaining acceptance in clinical practice. Owing to adverse reactions, the duration of the buildup phase until a maintenance dose is achieved may be prolonged, and in a minority of cases, OIT is stopped.

OBJECTIVE

We aimed to assess factors associated with the probability of reaching the maintenance dose in cow's milk (CM) OIT.

METHODS

We collected data from patients undergoing CM OIT at the Montreal Children's Hospital, BC Children's Hospital, and Hospital for Sick Children. We compared univariable and multivariable Cox regressions to evaluate sociodemographic factors, comorbidities, clinical characteristics, and biomarkers at study entry associated with the likelihood of reaching a maintenance dose of 200 mL of CM.

RESULTS

Among 69 children who reached 4 mL of milk, the median age was 12 years (interquartile range, 9-15 years); 59% were male. Median duration of buildup phase from 4 to 200 mL was 24.0 weeks (interquartile range, 17.7-33.4 weeks). After adjusting for age and sex, higher baseline levels of specific IgE antibodies for α-lactalbumin (hazard ratio [HR] = 0.80; 95% confidence interval [CI], 0.67-0.95), β-lactoglobulin (HR = 0.86; 95% CI, 0.76-0.98), casein (HR = 0.82; 95% CI, 0.72-0.94), and total CM (HR = 0.79; 95% CI, 0.65-0.97) were associated with a decreased probability of reaching maintenance. In addition, for every 10-mL increase in CM tolerated at entry challenge, the probability of reaching maintenance increased by 10%.

CONCLUSIONS

The data suggest that higher levels of CM-specific IgE decreased the likelihood of reaching maintenance, whereas an increased cumulative CM dose at entry challenge increased the likelihood. Assessing these factors before therapy may assist in predicting the success of CM OIT.

The prevalence and temporal trends of food allergy among preschool children in Northern Thailand between 2010 and 2019

Background

Although recent studies suggest that the prevalence of food allergy (FA) has not changed, the data from developing countries are limited. This study aimed to investigate time trends in the prevalence of FA among preschool children in 2010 and 2019 in Northern Thailand.

Methods

Two cross-sectional studies were performed, 9 years apart (2010 and 2019), using the same methods, in children aged 3–7 years living in Chiang Mai, Thailand. Parent-reporting questionnaire surveys were conducted. Families with children reporting FA were invited to undergo further investigations with skin prick testing, serum specific IgE, and oral food challenge (OFC). The prevalence of parent-reported FA, food sensitization, and OFC-confirmed FA were compared between the 2 periods.

Results

A total of 1013 out of 1146 questionnaires (452/546 in 2010 and 561/600 in 2019) were returned. The response rate was 88.4%. The prevalence of parent-reported food allergy in 2019 was significantly lower than that in 2010 (5.5% vs 9.3%; p = 0.02). However, there was no significant change in the prevalence of OFC-confirmed FA (0.9% vs 1.1%; p = 0.75). Three leading causative foods of parent-reported FA were cow's milk, shrimp, and eggs. Shrimp was still the most common OFC-confirmed food allergen. Atopic dermatitis was the most significantly parent reported factor associated with FA.

Conclusion

The overall prevalence of FA among preschool children in Northern Thailand had not increased during the past decade. There was no significant difference in the prevalence of OFC-confirmed FA between 2010 and 2019.

Sex-specific associations of human milk long-chain polyunsaturated fatty acids and infant allergic conditions

BACKGROUND

Polyunsaturated fatty acids (PUFAs) may influence immune development. We examined the association of PUFAs in human milk with food sensitization and atopic dermatitis among breastfed infants.

METHODS

In a selected subgroup of 1109 mother-infant dyads from the CHILD Cohort Study, human milk was analyzed by gas-liquid chromatography to quantify PUFAs including arachidonic acid (ARA) and docosahexaenoic acid (DHA). At 1 year of age, food sensitization was determined by skin-prick testing for egg, peanut, cow's milk, and soybean, and atopic dermatitis was diagnosed by pediatricians. Logistic regression analyses controlled for breastfeeding exclusivity, family history of atopy, and other potential confounders.

RESULTS

Overall, 184 infants (17%) were sensitized to one or more food allergens and 160 (14%) had atopic dermatitis. Sex-specific associations were observed between these conditions and milk PUFAs. Girls receiving human milk with lower proportions of DHA had lower odds of food sensitization (aOR 0.35; 95% CI 0.12, 0.99 for lowest vs highest quintile), and a clear dose-dependent association was observed for the ARA/DHA ratio (aOR 2.98; 95% CI 1.10, 8.06 for lowest vs highest quintile). These associations were not seen in boys. Similar sex-specific tendencies were observed for atopic dermatitis.

CONCLUSIONS

Human milk PUFA proportions and their ratios are associated with infant atopic conditions in a sex-specific manner. In female infants, a higher ratio of ARA/DHA may reduce the risk of food sensitization and atopic dermatitis. Further research is needed to determine the underlying mechanisms and clinical relevance of this sex-specific association.

Demographic characteristics associated with food allergy in a Nationwide Canadian Study

INTRODUCTION

We conducted a nationwide Canadian telephone survey on food allergy prevalence between February 2016 and January 2017, targeting vulnerable populations (New, Indigenous, and lower-income Canadians).

OBJECTIVE

To examine the independent effect of demographic characteristics on food allergy.

METHODS

Canadian households with vulnerable populations were targeted using Canadian Census data and the household respondent reported whether each household member had a perceived (self-reported) or probable (self-report of a convincing history or physician diagnosis) food allergy. The association between perceived and probable food allergy and demographic characteristics was assessed through weighted multivariable random effects logistic regressions.

RESULTS

Children, females, Canadian-born participants, adults with post-secondary education, and those residing in smaller households were more likely to report perceived or probable food allergy. Although immigrant parents self-reported less food allergy, Canadian-born children of Southeast/East Asian immigrant versus other immigrant or Canadian-born parents reported more food allergy.

CONCLUSION

We have demonstrated clear associations between demographic characteristics and food allergy, which may provide important clues to the environmental determinants of food allergy.

Time trends of childhood food allergy in China: Three cross-sectional surveys in 1999, 2009, and 2019

BACKGROUND

Many countries have recorded the trends of food allergy (FA) prevalence. Little is known about epidemiologic trends of childhood FA in China.

METHODS

In three cross-sectional surveys conducted in 1999, 2009, and 2019, the prevalence of and characteristic changes in FA in children aged ≤ 2 years were assessed and the outcomes were compared. All the children were recruited during well-baby check-ups at the Children's Hospital of Chongqing Medical University. All participants had a detailed medical history taken and underwent skin prick tests using ten commercial food extracts. Open food challenges were used for confirmation of FA.

RESULTS

The three studies included 1228 children (314 in 1999, 401 in 2009, and 513 in 2019; response rate > 95%). The prevalence of FA in 2009 (7.7%) and 2019 (11.1%) was significantly higher than that in 1999 (3.5%). However, there was no statistically significant difference in prevalence between 2009 and 2019 (P = .086). There was evidence of increased prevalence in CMPA between 1999 and 2019 (1.6% versus 5.7%; P = .004). However, no statistic difference was found in egg allergy (2.9% versus 5.5%; P = .21). The incidence of skin symptoms did not differ significantly over the study period, while the incidence of gastrointestinal symptoms increased significantly (18.2% in 1999, 12.9% in 2009, and 43.9% in 2019; P < .05).

CONCLUSIONS

The prevalence of FA in children rapidly increased after the 1990s and gradually stabilized after 2010. Cow's milk has become the most common food allergen among children in Chongqing. The incidence of gastrointestinal symptoms as a manifestation of FA has increased significantly since 2010.

Peanut and hazelnut occurrence as allergens in foodstuffs with precautionary allergen labeling in Canada

Precautionary allergen labeling (PAL) is widely used by food industries. Occurrence studies revealed that few analyzed products contained the allergen(s) present in the statement, but little is known in Canada. To improve manufacturing practices and better manage allergen cross-contamination, occurrence data is needed to determine the exposure of allergic individuals eating those products. Samples were analyzed for peanuts (n = 871) and hazelnuts (n = 863) using ELISA methods. Within samples analyzed for peanuts, 72% had a PAL (n = 628), 1% had peanuts as a minor ingredient (n = 9) and 27% were claimed “peanut-free” (n = 234). Most hazelnut samples had a PAL for tree nuts/hazelnuts (94%; n = 807) with 6% claimed “nut-free” (n = 56). Peanuts and hazelnuts were found in 4% (0.6–28.1 ppm) and 9% (0.4–2167 ppm) of all samples, respectively. Chocolates were mostly impacted; they should be treated apart from other foods and used in risk assessments scenarios to improve manufacturing practices, reducing unnecessary PAL use.

The global burden of illness of peanut allergy: A comprehensive literature review

Peanut allergy (PA) currently affects approximately 2% of the general population of Western nations and may be increasing in prevalence. Patients with PA and their families/caregivers bear a considerable burden of self‐management to avoid accidental peanut exposure and to administer emergency medication (adrenaline) if needed. Compared with other food allergies, PA is associated with higher rates of accidental exposure, severe reactions and potentially fatal anaphylaxis. Approximately 7%–14% of patients with PA experience accidental peanut exposure annually, and one‐third to one‐half may experience anaphylaxis, although fatalities are rare. These risks impose considerably high healthcare utilization and economic costs for patients with PA and restrictions on daily activities. Measures to accommodate patients with PA are often inadequate, with inconsistent standards for food labelling and inadequate safety policies in public establishments such as restaurants and schools. Children with PA are often bullied, resulting in sadness, humiliation and anxiety. These factors cumulatively contribute to significantly reduced health‐related quality of life for patients with PA and families/caregivers. Such factors also provide essential context for risk/benefit assessments of new PA therapies. This narrative review comprehensively assessed the various factors comprising the burden of PA.

Social and financial impacts of food allergy on the economically disadvantaged and advantaged families: A qualitative interview study

BACKGROUND

Differences in the qualitatively-perceived burden of food allergy based on economic disadvantages have not been previously described.

OBJECTIVE

To describe the perceptions of food allergy-related social and financial issues of families who have a child with food allergy, considering the similarities and differences between economically advantaged and disadvantaged families.

METHODS

From March to July 2019, we interviewed parents of children being followed up for food allergy at a tertiary allergy clinic in central Canada. Interviews were recorded, transcribed, and analyzed thematically. Economic groups were categorized on the basis of the national cutoffs for low-income after-tax dollars.

RESULTS

We interviewed 18 parents (17 [94.4% mothers]) of whom 6 (33.3%) were economically disadvantaged, and who represented 25 children (10 [40.0%] girls) with food allergy. We identified 3 common themes: food allergy had (1) resulted in the need to teach others in addition to contributing to tensions in relationships; (2) increased time costs for food shopping and preparation; and (3) contributed to concerns securing qualified child care. We also identified 2 divergent themes that underscored how this burden was perceived between economic groups: (1) medications and medical appointments are costly or inconvenient; and (2) allergy-friendly food choices: single vs several sources and servings.

CONCLUSION

Despite some qualitative similarities in the social and financial burdens of food allergy, there are some notable differences between economic groups that underscore the need for further discussions surrounding the related policy.

Probabilistic risk assessment for milk in dark chocolate, cookies and other baked goods with PAL sold in Canada

The risk of having an allergic reaction in milk-allergic individuals consuming products with precautionary allergen labelling (PAL) for milk has been rarely studied in products such as dark chocolate, cookies, and other baked goods. A probabilistic risk assessment model was developed to estimate potential risks. Milk occurrence and contamination levels were reported in a previous article from our group. Dose-response curves for milk were constructed using values (n = 1078) from published double-blind placebo-controlled food challenges. Canadian consumption data was extracted from a national survey, and a homemade survey involving food-allergic Canadians. Milk eliciting doses (ED) were 0.23 (ED₀₁), 1.34 (ED₀₅), 3.42 (ED₁₀), and 16.3 (ED₂₅) mg of milk protein (Log-Normal distribution). Average exposures, per eating occasion, were 24 mg (dark chocolate), 3.9 mg (baked goods), and 0.20 mg (cookies) of milk proteins. The estimated risk of having a milk-induced allergic reaction by consuming foods with PAL for milk was higher for dark chocolate (16%; 15,881/100,000) than baked goods (3.8%; 3802/100,000) or cookies (0.6%; 646/100,000) in milk-allergic Canadians. Dark chocolate, cookies, and baked goods with PAL for milk, should be avoided by milk-allergic Canadians (consuming or not products with PAL) to prevent allergic reactions.