Managing Cross-Reactivity in Those with Peanut Allergy.
Peanut is an allergenic legume that can cross-react with other plant-based foods, notably other legumes and tree nuts. Peanut allergic individuals can be both co-sensitized as well as co-allergic to such items, requiring foresight when eliciting a clinical history of reaction, in the diagnostic evaluation of such allergies, and in the counseling of patients as to food avoidances after a diagnosis is made. Legume allergens belong to the Fabaceae family and encompass the cupin, prolamin, PR-10, and LTP families, which mediate cross-sensitization including that between peanut and tree nut. Among legumes, the most common patterns of clinical cross-reactivity are between peanut and lupine, peanut and soy, as well as chickpea and lentil, though this is highly dependent upon geography and prevalence of these foods in the diet. Issues of cross-sensitization may exist between peanut and certain tree nuts, as well as among tree nuts though such patterns do not always result in clinically relevant allergy. Molecular diagnostic testing may be a future tool to help parse out the aforementioned patterns, but oral food challenges are still the gold standard for accurate diagnosis. Though potential desensitization treatments have emerged for peanut allergy, these have not been developed for other legumes and most tree nuts, and desensitization to peanut has not proven to have an effect on legume cross-sensitization.
Prevalence, severity, and distribution of adult-onset food allergy.
Introduction: While much attention has been devoted to food allergy in children, little is known about the prevalence and characteristics of food allergy in adults. Moreover, recent research has shown that increasing numbers of individuals are developing food allergy in adulthood. This population-based study was conducted to examine the prevalence, severity, and distribution of adult-onset food allergy. Methods: A survey was administered to 40,443 adult United States residents between 2015 and 2016. Population-level prevalence was estimated using complex survey weighting. Demographics, history of reactions and diagnosis for each allergen, and comorbid conditions were analyzed. Self-reported food allergies were considered convincing if symptoms were consistent with IgE-mediated reactions. Results: Among all adults with food allergy, 45.3% reported developing at least one food allergy after 18 years of age. Of these, 24.9% only experienced onset of food allergy in adulthood, and 54.7% only experienced onset of food allergy in childhood. The five most prevalent adult-onset food allergies included shellfish (13.3% of adults), milk (6.0%), wheat (5.6%), tree nut (4.8%), and soy (3.9%). More than half of individuals with adult-onset allergy to peanut, tree nut, fin fish, or shellfish reported a prior severe reaction to the allergen. Factors associated with development of adult-onset food allergy include female sex, increasing age, and a history of multiple food allergies, allergic rhinitis, or medication allergy. Conclusions: One in four adults with food allergy develop a food allergy for the first time as an adult. Further study is necessary to understand potential predictors of adult-onset food allergy.
AR101 oral immunotherapy for peanut allergy.
BACKGROUND: Peanut allergy, for which there are no approved treatment options, affects patients who are at risk for unpredictable and occasionally life-threatening allergic reactions. METHODS: In a phase 3 trial, we screened participants 4 to 55 years of age with peanut allergy for allergic dose-limiting symptoms at a challenge dose of 100 mg or less of peanut protein (approximately one third of a peanut kernel) in a double-blind, placebo-controlled food challenge. Participants with an allergic response were randomly assigned, in a 3:1 ratio, to receive AR101 (a peanut-derived investigational biologic oral immunotherapy drug) or placebo in an escalating-dose program. Participants who completed the regimen (i.e., received 300 mg per day of the maintenance regimen for approximately 24 weeks) underwent a double-blind, placebo-controlled food challenge at trial exit. The primary efficacy end point was the proportion of participants 4 to 17 years of age who could ingest a challenge dose of 600 mg or more, without dose-limiting symptoms. RESULTS: Of the 551 participants who received AR101 or placebo, 496 were 4 to 17 years of age; of these, 250 of 372 participants (67.2%) who received active treatment, as compared with 5 of 124 participants (4.0%) who received placebo, were able to ingest a dose of 600 mg or more of peanut protein, without dose-limiting symptoms, at the exit food challenge (difference, 63.2 percentage points; 95% confidence interval, 53.0 to 73.3; P<0.001). During the exit food challenge, the maximum severity of symptoms was moderate in 25% of the participants in the active-drug group and 59% of those in the placebo group and severe in 5% and 11%, respectively. Adverse events during the intervention period affected more than 95% of the participants 4 to 17 years of age. A total of 34.7% of the participants in the active-drug group had mild events, as compared with 50.0% of those in the placebo group; 59.7% and 44.4% of the participants, respectively, had events that were graded as moderate, and 4.3% and 0.8%, respectively, had events that were graded as severe. Efficacy was not shown in the participants 18 years of age or older. CONCLUSIONS: In this phase 3 trial of oral immunotherapy in children and adolescents who were highly allergic to peanut, treatment with AR101 resulted in higher doses of peanut protein that could be ingested without dose-limiting symptoms and in lower symptom severity during peanut exposure at the exit food challenge than placebo. (Funded by Aimmune Therapeutics; PALISADE ClinicalTrials.gov number, NCT02635776).
Severity of peanut allergy and the unmet gaps in care: a call to action.
Peanut allergy is one of the most common food allergies in children, with a prevalence that has been increasing over the past several decades. The allergy is a type I, immunoglobulin E (IgE)-mediated reaction that commonly presents in childhood and can be associated with an anaphylactic response. There are many theories that attempt to explain the increasing prevalence, including dietary changes, improvements in hygiene, and intentional allergen avoidance. Diagnosis is made through a combination of a thorough patient history, peanut-specific serum-specific IgE levels, peanut skin-prick test, and, if necessary, an oral food challenge. Guidelines based on the landmark 2015 Learning Early About Peanut Allergy trial suggest that peanuts should be introduced into the diet as early as 4 to 6 months of age in infants who are at highest risk of developing peanut allergy. It is important for providers to recognize risk factors for the development of peanut allergy, identify associated clinical symptoms, and provide an accurate diagnosis of patients to effectively manage them and their families and prevent future reactions.
Almond Allergy: An Overview on Prevalence, Thresholds, Regulations and Allergen Detection.
Food allergy has been on the increase for many years. The prevalence of allergy to different foods varies widely depending on type of food, frequency of consumption and geographic location. Data from the literature suggests that the prevalence of tree nut allergy is of the order of 1% in the general population. Almond is one such tree nut that is frequently eaten in many parts of the world and represents a potential allergenic hazard. Given the need to label products that contain allergens, a number of different methods of direct and indirect detection have been developed. However, in the absence of population-based threshold data, and given that almond allergy is rare, the sensitivity of the required detection is unknown and thus aims as low as possible. Typically, this is less than 1 ppm, which matches the thresholds that have been shown for other allergens. This review highlights the lack of quantitative data on prevalence and thresholds for almonds, which is limiting progress in consumer protection.
Correlation of negative skin-prick test results for tree nuts and successful tree nut challenges among children with peanut allergy.
Background: Children with peanut allergy are regularly instructed to avoid all tree nuts. However, children with peanut allergy are likely not allergic to all tree nuts. Objective: In our cohort of patients with peanut anaphylaxis and who underwent oral immunotherapy, we sought to determine the correlation of skin-prick testing (SPT) results for tree nuts and the likelihood of successfully passing a tree nut challenge. Methods: SPT was performed for peanut and tree nuts (macadamia, pine nut, coconut, hazelnut, brazil nut, cashew, pecan, walnut, pistachio, almond) in 27 patients with known peanut allergy. The probability of a negative SPT result (wheal < 3 mm) for each nut was determined. Results: All the patients demonstrated positive results in peanut allergy diagnostics in SPT, component testing, or food challenge. Only 15.4% of the patients had a positive SPT result to peanut alone. Macadamia, pine nut, and coconut SPT had a probability of negative SPT results of 0.97, 0.97, and 0.91, respectively. The odds ratio for this group having a negative SPT was 46.22. For hazelnut, Brazil nut, and cashew, the probability of a negative SPT result was 0.81, 0.77, and 0.73, respectively. Pecan, walnut, and pistachio had odds ratios of 0.68, 0.68, and 0.64, respectively. All the patients with macadamia, pine nut, and coconut negative SPT results subsequently passed 9-g food challenges without oral immunotherapy. Conclusion: Despite current recommendations to avoid all tree nuts for patients with peanut allergy, the majority of patients with peanut allergy had negative SPTs and food challenges to certain tree nuts, especially macadamia, pine nut, and coconut. This pattern was seen despite most patients having multiple nut sensitizations.
Comparing the eating out experiences of consumers seeking to avoid different food allergens.
BACKGROUND: Eating outside the home is challenging for consumers with food allergy (FA) and intolerance (FI) and lack of allergen information provision in eating out venues can lead to unnecessary restrictions. Following European legislation (2014) designed to improve allergen information provision, little is known about differences in information provision experienced by consumers seeking to avoid particular allergens, or how this impacts on their eating out experiences. This study compared the information provision that consumers with FA/FI to different allergens experience when eating out. METHODS: Using mixed methods, participants were recruited from across the UK and took part in self-report surveys or in-depth interviews. Surveys were completed by 232 participants avoiding either gluten (n = 66), nuts (peanuts/tree nuts) (n = 94), or milk (n = 74), and responses were subject to quantitative analyses. Interviews were carried out with 49 participants avoiding either gluten (n = 13), nuts (n = 14), milk (n = 13) or a combination of these allergens (n = 9), and analysed using the framework approach. RESULTS: Although general improvements in information provision following the legislation were reported, variations in provision between allergen groups led participants seeking to avoid milk to conclude that their dietary needs were less well-understood and seen as less important. These perceptions were reflected in a reluctance to involve eating out venue staff in deliberations about the potential for milk-free meal options. CONCLUSIONS: The provision of visual indicators of the presence of milk and of staff trained in allergen-awareness would improve the eating out experiences of consumers seeking to avoid milk. Medical professions can play a key role in encouraging these patients to pursue their right to make enquiries about allergens in order to avoid accidental milk ingestion when eating out.
UNECE Agricultural Quality Standards
The Chairperson of the Specialized Section on Standardization of Dry and Dried Produce, Mr. Dorian LaFond, reported the work of the Specialized Section and presented the revised standards and new recommendations submitted for adoption. As for the draft Sampling Plan for Tree Nuts and Dried Products and Guidelines for Inspection for Dry and Dried Produce, he highlighted the need for an inspection guideline and some provisions of the standards (e.g. mold filaments vs duvet in walnuts kernels) that require clarification by the Specialized Section.
The Working Party decided to adopt the new Standard for Dried Bananas and to adopt the revised Standard for Prunes, the new Standard for Dried Ripe Papayas and the new Standard for Dried Melons as a Recommendation for a 1-year trial period. In addition, explanatory posters for Inshell Walnuts, Walnut Kernels, Dried Figs and Dried Grapes are being developed.
Japan: MRLs Update
As for nuts and dried fruits, the following MRL were proposed:
- The MRL for probenazole in peanuts, cranberry, date, pecan, almond, walnut, and other nuts is lowered from 0.03 ppm to 0.01 ppm.
The deadline for comments is December 22, 2018.
For further information, please contact us at inc@nutfruit.org.
Australia and New Zealand: MRLs Update
Among others, the residue of indoxacarb in macadamia nuts at T*0.01 ppm is inserted. The final date for comments was December 4, 2018.
* indicates that the maximum residue limit is set at the limit of determination.
‘T’ indicates that the maximum residue limit is a temporary maximum residue limit.
The amendment can be found here.