Safety and Effectiveness of Bypassing Oral Immunotherapy Buildup With an Initial Phase of Sublingual Immunotherapy for Higher-Risk Food Allergy

BACKGROUND

Because of its favorable safety, sublingual immunotherapy (SLIT) for food allergy has been proposed as an alternative treatment for those in whom oral immunotherapy (OIT) is of higher risk-older children, adolescents, adults, and those with a history of severe reactions. Although safe, SLIT has been shown to be less effective than OIT.

OBJECTIVE

To describe the safety of multifood SLIT in pediatric patients aged 4 to 18 years and the effectiveness of bypassing OIT buildup with an initial phase of SLIT.

METHODS

Patients aged 4 to 18 years were offered (multi)food SLIT. Patients built up to 2 mg protein SLIT maintenance over the course of 3 to 5 visits under nurse supervision. After 1 to 2 years of daily SLIT maintenance, patients were offered a low-dose oral food challenge (OFC) (cumulative dose, 300 mg protein) with the goal of bypassing OIT buildup.

RESULTS

Between summer 2020 and winter 2023, 188 patients were enrolled in SLIT (median age, 11 years). Four patients (2.10%) received epinephrine during buildup and went to the emergency department, but none experienced grade 4 (severe) reaction. A subset of 20 patients had 50 low-dose OFCs to 300 mg protein and 35 (70%) OFCs were successful, thereby bypassing OIT buildup.

CONCLUSIONS

In combination with very favorable safety of SLIT, with no life-threatening reactions and few reactions requiring epinephrine, we propose that an initial phase of SLIT to bypass supervised OIT buildup be considered for children in whom OIT is considered to be of higher risk.

Bypassing the build-up phase for oral immunotherapy in shrimp-allergic children

Background

Oral immunotherapy is an effective treatment for food allergies; however, its use in clinical practice is limited by resources and lack of standardized protocols for foods other than peanut. Previous studies have suggested that shrimp has a higher threshold for reaction than other allergenic foods, suggesting it may be safe to directly administer maintenance doses of immunotherapy.

Methods

Children aged 3-17 years who had 1) skin prick test ≥3 mm and/or specific IgE level ≥0.35 kU/L and convincing objective IgE-mediated reaction to shrimp, or 2) no ingestion history and specific IgE level ≥5 kU/L, underwent a low-dose oral food challenge to 300 mg shrimp protein, with the goal of continuing daily ingestion of the 300 mg maintenance dose as oral immunotherapy.

Results

Between January 2020 and April 2023, 17 children completed the low-dose oral food challenge. Nine (53%) tolerated this amount with no reaction, and 8 (47%) had a mild reaction (isolated oral pruritis or redness on chin). Sixteen (94%) continued maintenance low-dose oral immunotherapy eating 300 mg shrimp protein daily. None of the patients developed anaphylaxis related to the immunotherapy.

Conclusion

Our case series suggests that some shrimp allergic patients being considered for oral immunotherapy should be offered a low-dose oral food challenge, to potentially bypass the build-up phase of immunotherapy.

Real-world safety and effectiveness analysis of low-dose preschool sesame oral immunotherapy

Background

Previous studies support the effectiveness of sesame oral immunotherapy (S-OIT) in patients >4 years old using maintenance doses of 1200 mg protein. However, tahini is often not palatable to children, and high-maintenance doses may not be possible for preschoolers.

Objective

We studied the safety and effectiveness outcomes of preschoolers with sesame allergy who underwent low-dose S-OIT of 200 mg protein.

Methods

Preschoolers with sesame allergy, with a history of objective reaction to sesame, and with either a positive skin prick test result (wheal diameter ≥3 mm) or sesame-specific IgE level ≥0.35 kU/L were included. Doses were escalated every 2 to 4 weeks until the maintenance dose of 200 mg of sesame protein was reached. The maintenance dose was continued daily for 1 year, followed by exit oral food challenge (OFC). Primary safety outcomes included allergic reactions grade 2 or higher and the need for epinephrine therapy during buildup. The primary effectiveness outcome was proportion of patients tolerating a minimum of 2000 mg sesame protein at exit OFC.

Results

Twenty-eight preschoolers (median age, 33.5 months) were enrolled to receive S-OIT. During the buildup phase, 9 subjects (32.1%) had no reaction, and 8 (28.6%) and 11 (39.3%) had grade 1 and 2 reactions, respectively. One patient (3.57%) received epinephrine for a grade 2 reaction. Twenty-one (91.3%) of 23 eligible subjects underwent exit OFC; 18 (85.7%) of these 21 patients successfully completed exit OFC. One (4.8%) and 2 (9.5%) subjects had grade 1 and 2 reactions, respectively, during OFC.

Conclusions

A lower and age-appropriate maintenance dose is safe and effective in desensitizing preschoolers with sesame 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.

Risk factors associated with safety of preschool peanut oral immunotherapy

Background

An understanding of how patient characteristics such as age, baseline peanut-specific IgE, and atopic comorbidities may influence potential safety outcomes during peanut oral immunotherapy (P-OIT) could aid in shared decision making between clinicians and patient families.

Objective

This study explored the relationship between baseline patient characteristics and reactions during P-OIT using a large sample size to better understand potential risk factors influencing P-OIT safety.

Methods

Data were obtained from the Food Allergy Immunotherapy (FAIT) registry, which collects real-world OIT data from community and academic allergy clinics across Canada. Multivariable logistic regression modeling was performed to examine the relationship between baseline patient characteristics and reactions during P-OIT. Multiple imputation was applied to reduce potential bias caused by missingness and to maximize the use of available information to preserve statistical power.

Results

Between April 2017 and June 2021, a total of 653 eligible patients initiated P-OIT. Multivariable regression analysis showed pre-OIT grade 2+ initial reaction (odds ratio [OR] = 1.33, 95% confidence interval [CI] 1.10, 1.61), allergic rhinitis (OR = 1.60, 95% CI 1.08, 2.38), older age (OR = 1.01, 95% CI 1.00, 1.02), and higher baseline peanut-specific IgE (OR = 1.02, 95% CI 1.02, 1.03) were associated with grade 2+ reaction during P-OIT after adjusting for potential risk factors.

Conclusion

Our study identified several clinically important risk factors for grade 2+ reactions during P-OIT: pre-OIT grade 2+ initial reaction, allergic rhinitis, older age, and higher baseline peanut-specific IgE. These results highlight the need for individualized risk stratification for OIT.

Comparing the risk of anaphylaxis requiring epinephrine in oral immunotherapy and subcutaneous immunotherapy: A review of recent Canadian real-world literature

Background

The safety of pediatric food oral immunotherapy (Ped-OIT) has been depicted by some as less favorable than subcutaneous immunotherapy (SCIT) owing to the increased number of serious adverse events requiring epinephrine. A review of real-world data comparing Ped-OIT and SCIT safety is necessary to guide shared decision making.

Objectives

Our aim was to compare the safety and adverse event profiles of peanut Ped-OIT and SCIT using Canadian real-word literature.

Methods

We performed a retrospective review of recent Canadian real-world literature on peanut Ped-OIT and SCIT safety and adverse events.

Results

The incidences of systemic reactions requiring epinephrine were 11 in 270 patients (4.07%) and 12 in 41,020 doses (0.029%) in a multicenter study in British Columbia, Alberta, Manitoba, and Nova Scotia studying 270 preschool-age children treated with peanut OIT. Similarly, a multicenter study in South-Western Ontario examining 160 patients between the ages of 1 and 17 years who were treated with peanut OIT showed that the incidences of systemic reactions requiring epinephrine were 5 in 160 patients (3.1%) and 8 in 52,751 doses (0.015%). A single-center retrospective review of 380 patients receiving aeroallergen SCIT showed that the incidences of systemic reactions requiring epinephrine were 28 in 380 patients (7.4%) and 1 in 1047 injection visits (0.095%). These findings are comparable to those of a review of 860 patients in Ontario who received either aeroallergen or venom SCIT, in which the incidence of systemic reaction requiring epinephrine was 10 in 4242 injections (0.24%).

Conclusion

Despite differences in the OIT protocols used and age groups studied, recent real-world data suggest that the safety of preschool peanut OIT or peanut OIT using a slower buildup schedule is comparable to that of SCIT.

A145 PEDIATRIC PATIENTS’ & PARENTS’ PERSPECTIVES ON TREATMENT PREFERENCE IN EOSINOPHILIC ESOPHAGITIS: A CROSS SECTIONAL, QUALITATIVE RESEARCH STUDY

Background

Eosinophilic esophagitis (EoE) is a chronic inflammatory disease of the esophagus which impairs quality of life in children and adolescents. Given the wide variety of symptomatic presentations in pediatrics, the varying time to diagnosis, and differing severity (including stricturing phenotype) initial treatments are not standardized. An important part of this individualization, beyond the health care practitioner counseling involves the patients’ and parents’ preferences which incorporates personal beliefs and attitudes.

Purpose

The study aim was to qualitatively describe parental and patient preferences regarding treatment options in EoE.

Method

This was a cross-sectional qualitative research study conducted in the EoE clinic at BC Children’s Hospital, Vancouver. Parents and their children completed semi-structured survey questions regarding treatment preference in EoE. Patients along with their parents who completed their survey questions were included in the study. Incomplete forms were excluded from the study.

Result(s)

The survey was attempted by 15 children, 7-11yrs of age, and 42 children, 12-18yrs of age, along with their parents. Completed response by both parent and their children were seen in 47 patients, 40 were adolescents 12-18yrs of age and 7 were 7-11yrs of age. Parent treatment preferences were diet in 17/47(36.2%), medications in 21/47 (44.7%) and 9/47 (19%) were unsure. 75% of parents who preferred dietary management thought it was less risky than medication. Parents who chose medication thought it would be easier (8/21) and more effective (8/21). Most of the parents’ decisions were influenced by the physician (35/47; 74.5%) and more so by the gastroenterologist (28/47; 59.6%). In 12–18-yr olds, 6/40 (15%) had preference for diet, 25/40 (62.5%) preferred medication and 9/40 (22.5%) were unsure. 3/6 adolescents thought that diet was less risky and 4/6 thought it was more effective than medication. Among the teens who preferred medication, 17/25 (68%) felt it to be easier and 9/25 (36%) thought it would work better than diet. Teenagers found their parents to be helpful for deciding (50%) and doctor (50%) with the gastroenterologist again playing a prominent role. In the 7 to 11yr old age group, 4/7 (57.1%) predominantly had preference for dietary treatment.

Conclusion(s)

The overall preference in the adolescent age group is for medication supported by patients’ and parents’, with ease of use being a primary driver for adolescents, whereas ease of use and effectiveness were drivers for the parents. Parents were more often interested in dietary therapy than the adolescents. With regards to parents of younger children and younger children themselves, dietary management was the preference as they felt it to be less risky. The numbers, though small, represent one of the few studies done on patient preference in EoE. Future studies should include formal qualitative studies and preferences could ultimately be tied to better counseling and tracking adherence to therapy.

Please acknowledge all funding agencies by checking the applicable boxes below

None

Disclosure of Interest

None Declared

Real-World Safety Analysis of Preschool Tree Nut Oral Immunotherapy

BACKGROUND

Our group previously described preschool peanut oral immunotherapy (OIT) in a real-world, multicenter setting, suggesting that this therapy is safe for most preschoolers.

OBJECTIVE

To examine the safety and tolerability of tree nut (TN) OIT in preschoolers in the real world.

METHODS

As part of a Canada-wide quality improvement project, TN-OIT (cashew/pistachio, walnut/pecan, hazelnut, almond, and macadamia nut) was performed in preschoolers who had (1) a skin prick test wheal diameter greater than or equal to 3 mm or a specific IgE level greater than or equal to 0.35 kU/L and a convincing objective IgE-mediated reaction or (2) no ingestion history and a specific IgE level greater than or equal to 5 kU/L. Dose escalations were performed every 2 to 4 weeks till a maintenance dose of 300 mg of TN protein was reached. Symptoms were recorded and classified using the modified World Allergy Organization Subcutaneous Immunotherapy Reaction Grading System (1, mildest; 5, fatal).

RESULTS

Of the 92 patients who started TN-OIT from 2018 to 2021, 79 (85.9%) underwent single-food TN-OIT and 13 (14.1%) underwent multifood TN-OIT to 2 (10.8%) or 3 (3.3%) TNs. Eighty-nine (96.7%) patients reached maintenance, and 4 (4.3%) dropped out. Sixty-five (70.7%) patients experienced reactions during buildup: 35 (38.0%) grade 1 reactions, 30 (32.6%) grade 2 reactions, no grade 3 or 4 reactions, and 2 (2.17%) received epinephrine.

CONCLUSIONS

Preschool TN-OIT in a real-world, multicenter setting appears safe and tolerable, with results comparable with our previously reported peanut OIT findings.

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.

Application of the Eosinophilic Esophagitis Histology Scoring System Grade Scores in Patients at British Columbia Children's Hospital

INTRODUCTION

Histologic diagnosis of eosinophilic esophagitis (EoE) involves peak eosinophil counts (PEC) being greater than 15 per high power field. The EoE Histology Scoring System (EoEHSS) was developed to comprehensively evaluate biopsies to better predict symptom and endoscopy response; we aimed to validate the EoEHSS in our provincial registry, where EoEHSS had not been employed.

METHODS

We reviewed 186 esophageal biopsies from 16 patients at diagnosis and follow-up. Statistical analyses were conducted to quantify how grade scores correlate with active EoE status and PEC counts, and each feature's ability to predict active disease.

RESULTS

Nearly all EoEHSS variables were associated with active EoE and high PEC, with basal zone hyperplasia, eosinophil abscesses, and surface epithelial alteration being most predictive in identifying active EoE.

CONCLUSIONS

We validated and demonstrated each EoEHSS variable's strength in tracking traditional PEC counts, resulting in its adoption as a standard reporting element for our research registry.

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.

Patient selection for milk and egg ladders using a food ladder safety checklist

A food ladder is a form of home-based dietary advancement therapy that gradually increases exposure to an allergenic food through the gradual introduction of egg or milk containing food with increasing quantity and allergenicity from extensively heated forms, such as baked goods, to less processed products. While widely considered safe, the food ladder is not risk-free and most of the egg and milk ladder studies only included preschoolers with mild egg and milk allergies, and with no or well-controlled asthma. We propose a Food Ladder Safety Checklist to assist with patient selection using “4 A's” based on available evidence for food ladders, including Age, active or poorly controlled Asthma, history of Anaphylaxis, and Adherence.

Food-allergy-specific anxiety and distress in parents of children with food allergy: A systematic review

BACKGROUND

Parenting a child with food allergy (FA) can lead to impaired quality of life and family functioning. Anxiety is a critical component of FA-associated distress and a potential target for therapeutic intervention. This systematic review aimed to clarify the concept of FA-specific anxiety (FAA) and its antecedents, consequences, and correlates and to determine the extent to which existing FA-specific outcome measures capture symptoms of parental distress and FAA.

METHODS

MEDLINE, EMBASE, PsycINFO, and CENTRAL were searched for qualitative and quantitative studies examining distress or anxiety in parents of children with FA through August 2020. This review was registered with PROSPERO (CRD42020208316) and conducted in accordance with PRISMA guidelines.

RESULTS

Ninety-eight studies were included in the final narrative synthesis. Most participants were mothers, and reporting of demographic data was limited. Parents identified anxiety as the most burdensome form of FA-specific emotional distress. Several allergy-related factors as well as medical and psychosocial interventions were associated with reduced parental anxiety and distress. However, affective, cognitive, and behavioral dimensions of FAA were only partially addressed by existing measures for general anxiety symptoms and FA-specific parental factors.

CONCLUSIONS

FAA contributes to distress and functional impairment among parents of children with FA. Current FA-specific parent measures fail to adequately capture dimensions of FAA, suggesting that further work is needed to improve the assessment and monitoring of FAA and its impacts. Characterization of this construct represents an initial step in developing standardized methods for assessing and monitoring FAA in clinical populations.

Home-Based Peanut Oral Immunotherapy for Low-Risk Peanut-Allergic Preschoolers During the COVID-19 Pandemic and Beyond

The coronavirus disease 2019 (COVID-19) pandemic has led to the deprioritization of non-emergency services, such as oral food challenges and the initiation of oral immunotherapy (OIT) for food-allergic children. Recent studies have suggested that home-based peanut OIT could be a safe and effective option for low-risk peanut-allergic children. In the period between September 1, 2020, and January 31, 2021, nine preschoolers with a history of mild allergic reactions to peanut underwent home-based peanut OIT. Eight of them (88.9%) completed the build-up phase at home in 11–28 weeks, tolerating a daily maintenance dose of 320 mg peanut protein. During the build-up, six patients (75.0%) reported urticaria, three (33.3%) reported gastrointestinal tract symptoms, and one (14.3%) reported oral pruritis. None of the patients developed anaphylaxis, required epinephrine, or attended emergency services related to OIT. One or two virtual follow-up visits were completed per patient during the build-up phase. Our case series shows that home-based OIT could be offered to the low-risk preschoolers during the COVID-19 pandemic when non-emergency services are limited and could be considered beyond the pandemic, especially for the families living in the rural or remote areas that may otherwise be unable to access OIT.