Peanut Introduction Research Articles

Dose and route of administration determine the efficacy of prophylactic immunotherapy for peanut allergy in a Brown Norway rat model.

Allergen-specific immunotherapy (IT) is emerging as a viable option for treatment of peanut allergy. Yet, prophylactic IT remains unexplored despite early introduction of peanut in infancy was shown to prevent allergy. There is a need to understand how allergens interact with the immune system depending on the route of administration, and how different dosages of allergen may protect from sensitisation and a clinical active allergy. Here we compared peanut allergen delivery via the oral, sublingual (SL), intragastric (IG) and subcutaneous (SC) routes for the prevention of peanut allergy in Brown Norway (BN) rats. BN rats were administered PBS or three different doses of peanut protein extract (PPE) via either oral IT (OIT), SLIT, IGIT or SCIT followed by intraperitoneal (IP) injections of PPE to assess the protection from peanut sensitisation. The development of IgE and IgG1 responses to PPE and the major peanut allergens were evaluated by ELISAs. The clinical response to PPE was assessed by an ear swelling test (EST) and proliferation was assessed by stimulating splenocytes with PPE. Low and medium dose OIT (1 and 10 mg) and all doses of SCIT (1, 10, 100 µg) induced sensitisation to PPE, whereas high dose OIT (100 mg), SLIT (10, 100 or 1000 µg) or IGIT (1, 10 and 100 mg) did not. High dose OIT and SLIT as well as high and medium dose IGIT prevented sensitisation from the following IP injections of PPE and suppressed PPE-specific IgE levels in a dose-dependent manner. Hence, administration of peanut protein via different routes confers different risks for sensitisation and protection from peanut allergy development. Overall, the IgE levels toward the individual major peanut allergens followed the PPE-specific IgE levels. Collectively, this study showed that the preventive effect of allergen-specific IT is determined by the interplay between the specific site of PPE delivery for presentation to the immune system, and the allergen quantity, and that targeting and modulating tolerance mechanisms at specific mucosal sites may be a prophylactic strategy for prevention of peanut allergy.

Conflicting Messages Regarding Infant Feeding May Encourage Delayed Introduction of Potentially Allergenic Foods

Guidelines for peanut allergy prevention recommend introduction of peanut as early as 4-6 months, seemingly at odds with recently renewed recommendations for exclusive breastfeeding for the first 6 months of life. We hypothesized that conflicting messages regarding infant feeding may encourage delayed introduction of peanut and other potentially allergenic foods.

Implementing Early Peanut Introduction Recommendations by Pediatric Residents through a Clinical Decision Support System

Early peanut introduction (PI) is recommended following the 2015 Learning Early about Peanut Allergy (LEAP) study. However, there remains a significant gap between the recommendations and implementation by primary care providers.

Development of Home Food Introduction Pathway Through Epic My Chart

Food allergy prevalence has been increasing in the United States to 7.6% of children. Many foods can safely be introduced at home, and do not require monitored challenges. We developed protocols for safe home introduction of peanut, milk, and egg products, via Epic MyChart ® patient portal. Our objectives were developing tools to support patients and families in the safe home introduction of foods and providing Allergists and PCP's with a mechanism to monitor patient progress.

Evaluation of Testing and Diagnosis of Tree Nut Allergy in Infants Undergoing Screening for Peanut Allergy

Current guidelines recommend early introduction of peanuts (PN) to all infants with an option of performing screening testing before introduction in those at highest risk for PN allergy. Specific guidelines on screening for tree nut (TN) allergy prior to introduction do not exist and the rate of PN/TN co-sensitization and allergy in this population is not known.

Estimating the Probability of Peanut Allergy Development in the Avoidance Arm of LEAP using Classification and Regression Tree Analysis

The Learning Early About Peanut Allergy (LEAP) trial showed that early dietary introduction of peanut reduced the risk of developing peanut allergy (PA) by age 60 months in children at high risk for PA. The influence of different baseline variables on the probability of developing PA within the peanut avoidance arm are not fully understood.

Physician Guidance Differences Among Race, Ethnicity And Socioeconomic Status For Early Introduction Of Peanut.

Over the past two decades, significant differences have been observed in the prevalence of food allergy across different racial and ethnic groups. Early introduction of peanut between 4 to 11 months of age has shown to reduce the frequency of peanut allergy. This study aims to identify differences in peanut-protein guidance across socioeconomic statuses.

Maternal Attitudes during Pregnancy regarding Food Allergy Prevention in Offspring

IgE-mediated food allergy has significant medical consequences and health-related costs; there is currently no cure once persistent food allergy has been established. In 2017, updated U.S. guidelines recommended early introduction of peanut for the prevention of food allergy in at-risk infants. Implementation of these guidelines is inconsistent. Given the limited window of opportunity for peanut introduction in infancy, providing anticipatory guidance during pregnancy may be important.

One Small Step for "Man," One Giant LEAP for Primary Care: A Quality Improvement Project Using EMR Standardization in the Primary Care Setting to Improve Guideline Adherence.

Seven years after the LEAP study, primary care providers (PCPs) have low adherence to the 2017 addendum guidelines to prevent peanut allergy in infants. The aims of this quality improvement (QI) project were to increase documentation of appropriate early peanut introduction (EPI) guidance by PCPs during routine 4, 6, and 9-month well-child check (WCC) encounters without negatively impacting balancing measures.

Defining the window of opportunity and target populations to prevent peanut allergy

Peanut allergy affects 1% to 2% of European children. Early introduction of peanut into the diet reduces allergy in high-risk infants. We aimed to determine the optimal target populations and timing of introduction of peanut products to prevent peanut allergy in the general population. Data from the Enquiring About Tolerance (EAT; n=1303; normal risk; 3-year follow-up; ISRCTN14254740) and Learning Early About Peanut Allergy study (LEAP; n=640; high risk; 5-year follow-up; NCT00329784) randomized controlled trials plus the Peanut Allergy Sensitization (PAS; n= 194; low and very high risk; 5-year follow-up) observational study were used to model the intervention in a general population. Peanut allergy was defined by blinded peanut challenge or diagnostic skin prick test result. Targeting only the highest-risk infants with severe eczema reduced the population disease burden by only 4.6%. Greatest reductions in peanut allergy were seen when the intervention was targeted only to the larger but lower-risk groups. A77% reduction in peanut allergy was estimated when peanut was introduced to the diet of all infants, at 4 months with eczema, and at 6 months without eczema. The estimated reduction in peanut allergy diminished with every month of delayed introduction. If introduction was delayed to 12 months, peanut allergy was only reduced by 33%. The preventive benefit of early introduction of peanut products into the diet decreases as age at introduction increases. In countries where peanut allergy is a public health concern, health care professionals should help parents introduce peanut products into their infants' diet at 4 to 6 months of life.

Food allergen introduction patterns in the first year of life: AUS nationwide survey.

Prevention guidelines have changed over the past decade and now recommend the earlier introduction of peanut and egg without delaying the introduction of other food allergens. This paper explored caregiver practices regarding the introduction of food allergens during infancy. A survey was administered (2021) to a US population-based sample of 3062 caregivers (children 7months - 3.5 years). Demographics and feeding practices were collected. Weighted frequencies and proportions were calculated using the svyr package in R 4.1. Survey-weighted chi-square statistics and covariate-adjusted, survey-weighted logistic regression models were used for statistical inference. Cow's milk, wheat, and soy were the top three allergens introduced. Peanut and egg were introduced by 17.2% and 15.5% of caregivers before 7months and 58.8% and 66.4% before 1year, respectively. The age of peanut and egg introduction differed significantly by race/ethnicity (p < .001) and caregiver age (p < .001). Peanut and egg introduction before 7months was significantly associated with the increased introduction of other allergenic foods before 1year (p=<.001; peanut and p=< .001; egg). Caregivers who introduced peanut and egg before 7months infant age fed an additional mean of 5.4 and 4.5 food allergens, respectively, before 1year. Few caregivers (0.9%) reported feeding an "early food allergen introduction product" ≥ 3 times, which was significantly associated with parental food allergy (OR=2.2) and previously seen an allergist (OR=6.7). More than half of the caregivers are not introducing peanut by age of one year and one-third are not introducing egg, though an observed shift toward earlier peanut and egg introduction was seen in the past 5 years. Peanut and egg introduction seem to co-occur and are associated with increased intake of other food allergens.

Food protein-induced enterocolitis syndrome to peanuts: A case series

Food protein-induced enterocolitis (FPIES) is a non–IgE-mediated food allergy that manifests as repetitive emesis, pallor, lethargy, and diarrhea onset 1 to 4 hours after the ingestion of a food.1 Since the implementation of guidelines advocating the early introduction of peanut, there has been an increase in publications about peanut FPIES (p-FPIES).2-4 Many have hypothesized that the early introduction may be the reason for FPIES to peanut in susceptible individuals. Although clinicians often see this in the clinic, there is much uncertainty regarding the characteristics and prognosis of p-FPIES.

AN EMR INTERVENTION TO IMPROVE EARLY INTRODUCTION OF PEANUTS IN INFANTS AT COMMUNITY-BASED HEALTH CLINICS

<h3>Introduction</h3> Infant peanut introduction is a recommended childhood feeding practice, following the landmark LEAP study showing that early introduction of peanut dramatically reduced rates of peanut allergy in high-risk infants. However, counselling about early introduction at infant well visits may not be happening systematically in all primary care settings. <h3>Methods</h3> In April 2019, we introduced an EMR screening tool in our general pediatrics clinics to discuss peanut allergy risk factors and early peanut introduction at well visits between 4-11 months. A retrospective chart review was undertaken, comparing all infants seen for 4-11 month old well visits in the year following the intervention (April 2019-March 2020) versus the year prior to the intervention (April 2018-March 2019). <h3>Results</h3> A total of 379 charts were screened, 179 pre-intervention and 200 post-intervention. There were no statistically significant differences in baseline characteristics in the pre-intervention and post-intervention groups, including age, sex, and comorbid egg allergy and eczema. Post-intervention, there was a statistically significant increase in discussion of early peanut introduction. 7 infants were screened pre-intervention, while 56 were screened after (p<0.001). There was a statistically significant increase in documentation of peanut in the diet by 12 months, with 5 documented pre-intervention and 23 post-intervention (p=0.001). <h3>Conclusion</h3> While introduction of the EMR screening tool increased discussion of early peanut introduction in community-based clinics, most infants still didn't have documentation of counselling on early peanut introduction in their medical records. Further interventions to improve rates of early peanut introduction are necessary to minimize development of peanut allergy.

DEVELOPING AN INFANT ATOPIC DERMATITIS SCORECARD FOR PEDIATRIC CLINICIANS

<h3>Introduction</h3> Accurate diagnosis and categorization of infant atopic dermatitis (AD) is necessary for assessing risk prior to early peanut introduction. AD assessment tools were primarily developed for research purposes and not for clinical use. Objective:To develop an infant AD scorecard with a focus on diverse skin tones to assist pediatric clinicians with AD assessments. <h3>Methods</h3> Parents of children with AD diagnosis were contacted and consented to provide high-resolution standardized photographs of their infant's AD lesions. Two dermatologists reviewed all images and determined AD severity using the Validated Investigator Global Assessment for Atopic Dermatitis (vIGA-AD). An instructional video about AD and how to use the scorecard was developed and presented to pediatric clinicians. <h3>Results</h3> Overall, photographs of 13 children were obtained: 6 children were photographed by research staff and 7 provided images of their infants using the same standardized photographic protocol. Two pediatric dermatologists evaluated 58 infant's images, with 84% agreement on first-pass severity categorization. Of these, 14 images were selected representing 2 White, 2 Black, 1 mixed race, and 2 Hispanic/LatinX infants. These images were used to develop the final scorecard which included 5 mild, 5 moderate, and 4 severe cases of AD. Overall, 189 pediatricians completed an educational module on AD categorization and vIGA-AD scorecard. Initial feedback surveys (N=14) 64.3% reported the training was "very effective." Observation of utilization and effectiveness of the scorecard and training is ongoing. <h3>Conclusion</h3> Development of an infant AD scorecard can assist pediatric providers in assessing peanut allergy risk prior to early introduction.

IMPACT OF EARLY PEANUT INTRODUCTION GUIDELINES ON INFANT TREE NUT ALLERGY TESTING

<h3>Introduction</h3> Tree nut allergy, like peanut allergy, is a common cause of severe food allergic reactions. The impact of the 2017 early peanut introduction guidelines on tree nut allergy testing in infants has not been well studied. <h3>Methods</h3> We performed a retrospective cohort study of infants less than age 1 year with Kaiser Permanente Northern California insurance coverage and had food-specific sIgE testing from January 2015 to December 2020. Our outcome of interest was sIgE testing rates for the following tree nuts: almond, Brazil nut, cashew, hazelnut, pecan, pistachio, and walnut. <h3>Results</h3> Among 3340 infants undergoing food-specific sIgE testing, the sIgE testing rates (per 1000 infants) increased for all tree nuts studied from 2015 to 2020 (p<0.001, Figure). Year-to-year analysis showed that sIgE testing rates increased for most tree nuts from 2017 to 2018 following publication of the early peanut introduction guidelines: almond (p=0.001), Brazil nut (p=0.001), hazelnut (p=0.001), pecan (p=0.004), and pistachio (p=0.002). sIgE testing rates for cashew and walnut also trended upward but decreased significantly from 2018 to 2019 following removal of a food allergy screening panel containing both nuts (p=0.01 for cashew, p=0.035 for walnut). <h3>Conclusion</h3> Infant sIgE testing rates increased significantly for all tree nuts following the 2017 early peanut introduction guidelines and decreased for selected tree nuts following removal of a food allergy screening panel. More studies are needed to assess the utility of tree nut sIgE testing in infants and the impact of early food introduction on tree nut allergy prevalence.

Evaluating the predictive utility of patient‐oriented scoring of atopic dermatitis (PO‐SCORAD) versus Patient‐Oriented Eczema Measure (POEM) for peanut sensitivity in patients with atopic dermatitis

AbstractBackgroundCurrent Guidelines from the National Institute of Allergy and Infectious Disease (NIAID) are based on the Learning Early About Peanut Allergy Study (LEAP Study) results and recommend early introduction of peanuts to children with atopic dermatitis (AD) depending on their disease severity. There is yet to be a widely accepted method of evaluating AD severity among clinicians. Thus, the purpose of this study was to determine the association between AD severity as measured by patient‐oriented scoring of atopic dermatitis(PO‐SCORAD) and Patient Oriented Eczema Measure (POEM) surveys and peanut sensitivity as measured by Immunoglobulin E (IgE) or skin prick test levels.ObjectivesThe primary objective of this study was to determine the association between AD severity as measured by PO‐SCORAD and POEM surveys and peanut sensitivity as measured by IgE or skin prick test levels. The secondary objective of this study was to determine the rate of peanut sensitisation amongst patients with ‘mild AD’ as defined by PO‐SCORAD score of 1−27 and a POEM score of 0‐7.MethodsPatients between 3 months and 18 years old undergoing IgE or skin prick testing for peanut allergy were recruited from two allergy clinics in the Chicagoland area. Patients or their guardians completed a PO‐SCORAD survey and POEM survey.ResultsThere was no significant difference in AD severity (as measured by PO‐SCORAD or POEM score) between sexes or age groups (&lt;12 months vs. ≥12 months). Moreover, there was no significant relationship found between PO‐SCORAD or POEM scores and rate of peanut sensitivity.ConclusionDespite no significant relationship found between PO‐SCORAD or POEM score and peanut sensitivity, the hypothesis that AD severity can predict risk of peanut sensitivity may still be valid based on a growing body of evidence. The negative results of this study are likely due to the small study population used due to limitations of the COVID‐19 pandemic. Moreover, evaluating AD severity through PO‐SCORAD and POEM surveys may not be ideal for paediatric patients.

The health disparities of early introduction of allergenic foods

Current guidelines in the United States recommend early introduction of peanut using a screening approach pending the child's history of eczema or egg allergy.1,2 Unfortunately, implementation of the guidelines has proven to be challenging.3-6 Given this, a consensus statement in North America suggested simply introducing peanut in the diet of all infants using a shared decision-making approach.7 Unfortunately, there is little known about whether parents are receiving education and whether this affects early introduction.

Association Between Earlier Introduction of Peanut and Prevalence of Peanut Allergy in Infants in Australia

Randomized clinical trials showed that earlier peanut introduction can prevent peanut allergy in select high-risk populations. This led to changes in infant feeding guidelines in 2016 to recommend early peanut introduction for all infants to reduce the risk of peanut allergy. To measure the change in population prevalence of peanut allergy in infants after the introduction of these new guidelines and evaluate the association between early peanut introduction and peanut allergy. Two population-based cross-sectional samples of infants aged 12 months were recruited 10 years apart using the same sampling frame and methods to allow comparison of changes over time. Infants were recruited from immunization centers around Melbourne, Australia. Infants attending their 12-month immunization visit were eligible to participate (eligible age range, 11-15 months), regardless of history of peanut exposure or allergy history. Questionnaires collected data on demographics, food allergy risk factors, peanut introduction, and reactions. All infants underwent skin prick tests to peanut and those with positive results underwent oral food challenges. Prevalence estimates were standardized to account for changes in population demographics over time. This study included 7209 infants (1933 in 2018-2019 and 5276 in 2007-2011). Of the participants in the older vs more recent cohort, 51.8% vs 50.8% were male; median (IQR) ages were 12.5 (12.2-13.0) months vs 12.4 (12.2-12.9) months. There was an increase in infants of East Asian ancestry over time (16.5% in 2018-2019 vs 10.5% in 2007-2011), which is a food allergy risk factor. After standardizing for infant ancestry and other demographics changes, peanut allergy prevalence was 2.6% (95% CI, 1.8%-3.4%) in 2018-2019, compared with 3.1% in 2007-2011 (difference, -0.5% [95% CI, -1.4% to 0.4%]; P = .26). Earlier age of peanut introduction was significantly associated with a lower risk of peanut allergy among infants of Australian ancestry in 2018-2019 (age 12 months compared with age 6 months or younger: adjusted odds ratio, 0.08 [05% CI, 0.02-0.36]; age 12 months compared with 7 to less than 10 months: adjusted odds ratio, 0.09 [95% CI, 0.02-0.53]), but not significant among infants of East Asian ancestry (P for interaction = .002). In cross-sectional analyses, introduction of a guideline recommending early peanut introduction in Australia was not associated with a statistically significant lower or higher prevalence of peanut allergy across the population.

How primary care providers can help prevent food allergies

IgE-mediated food allergy rates have increased in recent decades, yet treatment options remain limited. Prevention strategies are thus essential. We will review recent research and consensus guidelines for food allergy prevention. Research has continued to support that early introduction of allergens via the gastrointestinal tract induces tolerance and prevents development of food allergy. In contrast, allergen sensitization may occur via transcutaneous allergen exposure. This is supported by research that shows a decreased risk of food allergy with aggressive treatment of atopic dermatitis. More recent research suggests that transcutaneous sensitization could also be facilitated by frequent emollient use in the absence of atopic dermatitis but definitive research is lacking. Murine models have shown a likely role of dysbiosis, or disruption of the body's normal healthy microbiome, in development of food allergy, yet human studies have yet to show a conclusive benefit of probiotics in the prevention of food allergy. Important approaches for food allergy prevention are: introduction of peanut and cooked egg at 4-6 months, early introduction of other allergenic foods, and early diagnosis and treatment of atopic dermatitis (because of a predisposition to food sensitization through the damaged skin barrier). More research is needed to clarify the role, if any, of emollient use and probiotics.

The Case for Prompt Salvage Infant Peanut Oral Immunotherapy Following Failed Primary Prevention

Recent guideline recommendations have shifted from recommending prolonged avoidance of allergenic foods in the first 3 years of life to a primary prevention approach involving the deliberate early introduction to infants at risk of developing food allergy. Despite this, some infants, especially those with severe eczema who are at highest risk for developing peanut allergy, fail to receive the preventative benefits of early peanut introduction due to hesitancy and other factors. Difficulty adhering to regular ingestion after introduction further reduces the effectiveness of primary prevention. As emerging real-world evidence has demonstrated that performing peanut oral immunotherapy (OIT) among infants is effective and safe, peanut OIT could be a treatment option for infants with peanut allergy. This review discusses the benefits, risks, and barriers to offering peanut OIT to infants who fail primary prevention strategies. We propose the novel concept that infants with peanut allergy be offered peanut OIT as soon as possible after failed peanut introduction through a shared decision-making process with the family, where there is a preference for active management rather than avoidance.