Egg Food Challenges are Associated with More Gastrointestinal Reactions

Cow's milk and egg protein threshold dose distributions in children tolerant to beef, baked milk, and baked egg

BACKGROUND

The use of eliciting doses (EDs) for food allergens is necessary to inform individual dietary advice and food allergen risk-management. The Eliciting Dose 01 (ED01) for milk and egg, calculated from populations of allergic subjects undergoing oral food challenges (OFCs), are 0.2 mg total protein. The respective Eliciting Dose 05 (ED05) is 2.4 mg for milk and 2.3 mg for egg. As about 70% children allergic to such foods may tolerate them when baked, we sought to verify the EDs of that subpopulation of milk and egg-allergic children.

METHODS

We retrospectively assessed consecutive OFC for fresh milk and egg between January 2018 and December 2020 in a population of baked food-tolerant children.

RESULTS

Among 288 children (median age 56 - IQR 36-92.5 months, 67.1% male) included, 87 (30.2%) returned positive OFC results, 38 with milk and 49 with egg. The most conservative ED01 was 0.3 mg total protein (IQR 0.03-2.9) for milk and 14.4 mg total protein (IQR 3.6-56.9) for egg. The respective ED05 was 4.2 (IQR 0.9-19.6) mg for milk and 87.7 (IQR 43-179) mg for egg. Such thresholds are, respectively, 1.5 (milk ED01), 1.75 (milk ED05), 72 (egg ED01), and 38.35 (egg ED05) times higher than the currently used thresholds.

CONCLUSIONS

The subpopulation of children allergic to milk and egg, but tolerant to baked proteins, displays higher reactivity thresholds than the general population of children allergic to milk and egg. Their risk stratification, in both individual and population terms, should consider this difference. In baked milk-tolerant children, milk causes reactions at lower doses than egg in our group of egg-tolerant children. This could be associated with the relative harmlessness of egg compared with milk in the determinism of fatal anaphylactic reactions in children.

Organ-specific symptom patterns during oral food challenge in children with peanut and tree nut allergy

BACKGROUND

Peanut and tree nut allergies are common in childhood and often severe in nature. The clinical picture shows a wide variety of symptoms.

OBJECTIVE

To analyze the distribution of clinical symptoms and severity during oral food challenges (OFC) in children.

METHODS

Analysis of 1.013 prospectively recorded, positive OFCs with peanut (n = 607), hazelnut (n = 266), walnut (n = 97), and cashew (n = 43). Symptoms were categorized as immediate-type skin, gastrointestinal, upper and lower respiratory, cardiovascular symptoms, and eczema exacerbation. Symptom severity and treatment were recorded.

RESULTS

Skin symptoms presented in 78%, followed by gastrointestinal (47%), upper (42%), and lower respiratory symptoms (32%). Cardiovascular symptoms presented in 6%. In three-quarter of the reactions, more than one organ was involved. Importantly, severe reactions occurred at every dose level. Peanut- and cashew-allergic patients had a higher relative risk of gastrointestinal symptoms compared with hazelnut- and walnut-allergic patients. Patients without vomiting had a 1.7 times higher risk developing immediate-type skin and/or lower respiratory symptoms. Three-quarter of the patients ever had eczema but worsening presented in only 10.5% of the OFCs. In patients with multiple food allergies, organs involved, eliciting dose and severity differed between allergens.

CONCLUSION

Although comparisons between allergen groups with different clinical history, severity, comorbidities and laboratory data are difficult and might contain bias, our data confirm the high allergenic potential of peanut and tree nuts. The rare occurrence of eczema worsening emphasizes that avoidance diets of peanuts and tree nuts to cure eczema seem to be unnecessary and may hamper tolerance maintenance.

Differences in allergic symptoms after the consumption of egg yolk and egg white

Hen’s eggs are one of the most common causes of food allergy. Although hen’s eggs are known to cause more gastrointestinal symptoms than other foods, it is not known whether there is a difference in organ-specific symptoms between egg yolk (EY) and egg white (EW). The present study aimed to determine whether there are organ-specific differences in the immediate symptoms of EY and EW in patients with hen’s egg allergies. We retrospectively investigated the immediate symptoms and treatment contents of those who had a positive result in an oral food challenge (OFC) of boiled whole EY or 10 g of boiled EW in our hospital from January 2013 to July 2019. We compared 80 patients in the EY-OFC-positive group with 106 patients in the EW-OFC-positive group. The EY-OFC-positive group had significantly fewer respiratory symptoms and significantly more gastrointestinal symptoms than the EW-OFC-positive group and had significantly more gastrointestinal symptoms only. In terms of treatment, significantly fewer patients in the EY-OFC-positive group required beta 2-agonist inhalation, and a significantly higher proportion of patients did not require treatment. Compared to EW, EY is more likely to cause gastrointestinal symptoms and less likely to cause respiratory symptoms. It may be necessary to discriminate between EY and EW allergy during diagnosis.

Self-administration of adrenaline for anaphylaxis during in-hospital food challenges improves health-related quality of life

OBJECTIVE

To assess the impact of anaphylaxis on health-related quality of life (HRQL) and self-efficacy in food-allergic patients undergoing in-hospital food challenge.

DESIGN

Secondary analysis of a randomised controlled trial.

SETTING

Specialist allergy centre.

PATIENTS

Peanut-allergic young people aged 8-16 years.

INTERVENTIONS

Double-blind, placebo-controlled food challenge to peanut, with HRQL and self-efficacy assessed using validated questionnaire, approximately 2 weeks prior to and 2 weeks after challenge. Where possible, anaphylaxis was treated with self-injected adrenaline (epinephrine).

MAIN OUTCOME MEASURES

Change in HRQL and self-efficacy.

RESULTS

56 participants had reactions at food challenge, of whom 16 (29%) had anaphylaxis. Overall, there was an improvement in HRQL (mean 2.6 points (95% CI 0.3 to 4.8); p=0.030) and self-efficacy (mean 4.1 points (95% CI 2.4 to 5.9); p<0.0001), independent of whether anaphylaxis occurred. Parents also reported improved HRQL (mean 10.3 points (95% CI 5.9 to 14.7); p<0.0001). We found evidence of discordance between the improvement in HRQL and self-efficacy as reported by young people and that perceived by parents in their child.

CONCLUSIONS

Anaphylaxis at food challenge, followed by self-administration of injected adrenaline, was associated with an increase in HRQL and self-efficacy in young people with peanut allergy. We found no evidence that the occurrence of anaphylaxis had a detrimental effect. Young people should be encouraged to self-administer adrenaline using their autoinjector device to treat anaphylaxis at in-hospital challenge.

TRIAL REGISTRATION NUMBER

NCT02149719.

Delayed and Severe Reactions to Baked Egg and Baked Milk Challenges

BACKGROUND

Although many egg- and milk-allergic children tolerate baked egg (BE) and baked milk (BM), reactions elicited by these oral food challenges (OFCs) can be severe. Previous studies comparing BE and BM reactions to other OFC reactions are limited.

OBJECTIVE

To compare the clinical features of reactions to BE and BM with other OFCs to promote challenge safety.

METHODS

A retrospective review of OFCs eliciting objective reactions to BE, BM, lightly cooked egg (CE), fresh cow's milk (CM), peanut (PN), and tree nuts (TN) which were performed at a tertiary referral center from June 1, 2017, to June 1, 2019.

RESULTS

We identified 174 OFCs conducted in 158 subjects, age 6 to 187 months (34 BE, 19 BM, 14 CE, 25 CM, 52 PN, and 30 TN). TN reactors were older than BE (P = .049) and PN (P < .01) reactors and had a higher frequency of persistent asthma than PN-reactive subjects (P = .02). Mucocutaneous symptoms occurred less frequently during BE (56%) and BM (42%) OFCs compared with other OFCs (P < .05). Lower respiratory tract reactions were increased during BM (37%) versus BE (12%), CM (8%), and PN (12%) OFCs (P < .05). Epinephrine was administered to more BE (44%) and TN (50%) than PN (17%) OFCs (P < .01). New reaction manifestations developed 60 minutes or later after OFC termination during 29% BE and 21% BM versus 0% PN OFCs (P < .05). One-third of anaphylactic reactions to BE began more than 60 minutes after OFC termination.

CONCLUSIONS

BE and BM challenge reactions differed phenotypically from other OFC reactions, including significantly increased frequencies of new symptoms beginning 60 minutes or later after challenge termination. Consider amended dose-escalation and prolonged observation after BE and BM OFCs.

The effect of age, sex, race/ethnicity, health insurance, and food specific serum immunoglobulin E on outcomes of oral food challenges

Background

Although oral food challenge (OFC) is an important clinical procedure for diagnosing food allergy, there is a paucity of literature on the outcome of the procedure and specifically the patients on whom the procedure is performed from the aspects of their age, sex, race/ethnicity, health insurance status, and serum specific IgE to the food tested.

Objective

We aimed to review results of OFC and determine the impact of patient age, sex, race/ethnicity, insurance status, private or public, and food specific serum IgE on the outcome of OFC.

Methods

A retrospective chart review was performed of patients undergoing OFCs at a children's hospital outpatient allergy clinic over a two-year period. The outcome of OFC was allergic or non-allergic based on determination and documentation by the treating physician. A logistic regression model was built to determine the association between the OFC outcomes, age, and symptoms at the time of OFC. A Chi-square analysis was performed to check for any significant relationship between the OFC outcome and age when stratified by insurance status.

Results

Five hundred and eight children underwent 641 OFCs. Twenty nine percent of OFCs had an allergic outcome with the most commonly challenged foods being peanuts, eggs, and milk. Patient age and gender, when stratified by insurance status, did not have a significant effect on OFC outcomes. Serum IgE to peanuts and egg was significantly different between allergic OFC and non-allergic outcome. Vomiting and urticaria/angioedema correlated with an allergic OFC outcome.

Conclusion

OFCs confirm the food allergy diagnosis in about one-third of patients tested, and they should continue to be used when possible for an accurate diagnosis. Age, sex, and insurance status do not have a significant association with the outcome of OFC and cannot be added as predictive factors.

Lip Dose Challenges in Food Allergy: Current Practice and Diagnostic Utility in the United Kingdom

Background

Lip dose challenges (LDCs) are often performed as an initial step before oral food challenges (OFCs). However, guidance on how to perform and interpret LDCs is unclear, and data are lacking regarding the diagnostic accuracy of LDCs.

Objective

To investigate current practice with respect to LDCs among UK allergy health care professionals, and to evaluate the diagnostic utility of LDCs in children undergoing OFCs for IgE-mediated food allergy.

Methods

We used an electronic survey to assess the use of LDCs by UK Allergy clinics. Separately, we prospectively recruited children undergoing “low-risk” OFCs for suspected IgE-mediated food allergy from 2 large specialist allergy units in London. LDC was performed 30 minutes before the OFC, by applying the food to the inner lip for 30 seconds. Objective symptoms were considered a positive outcome. All patients subsequently proceeded to OFC regardless of LDC outcome, and outcome assessed according to PRACTALL consensus.

Results

We received 147 responses to the online survey, representing 67% of registered pediatric allergy clinics in the United Kingdom. Eighty percent of respondents (representing 81% of responding centers) included LDC as the first step of OFC in routine clinical practice. There was a wide variation in both how LDCs were performed and interpreted, with one-third not proceeding to OFC if LDC resulted in subjective symptoms. In the prospective study, 198 children (mean age, 7 years) with conclusive OFCs were included. Foods tested were tree nuts (30%), peanut (16.6%), egg (16%), fish (10.5%), milk (6%), shrimp (4%), and other (16.9%). There were 12 positive LDCs (1 of which triggered systemic symptoms: generalized urticaria) and 31 positive OFCs. Two children with positive LDCs went on to have a negative diagnostic OFC. Sensitivity of LDC was 32%, specificity 98%, with a false-negative rate of 68%.

Conclusions

Most UK allergy clinics included LDC as an initial step during OFC, despite a wide variation in how LDCs are performed and interpreted, which raises major concerns about the reproducibility and the validity of the test. We found that LDC had poor sensitivity as an alternative or initial step to formal OFC.

Minimal impact of extensive heating of hen's egg and cow's milk in a food matrix on threshold dose-distribution curves

We analyzed reaction threshold data from 352 children undergoing open food challenges to hen's egg or cow's milk, either fresh or extensively heated into a muffin. There was no significant shift in dose-distribution curves due to the baking process, implying that existing threshold data for these allergens can be applied to allergen risk management, even when these allergens are heat-processed into baked foods.

Risk Factors for Severe Reactions during Double-Blind Placebo-Controlled Food Challenges

BACKGROUND

Severe anaphylactic symptoms can occur during oral food challenges (OFCs). Thus, high-risk patients (e.g., patients with a history of anaphylaxis or high antigen-specific immunoglobulin E [IgE] levels) must carefully undergo OFCs in hospitals. We attempted to identify the risk factors for severe symptoms during OFC testing among high-risk patients.

METHODS

We retrospectively evaluated patients' characteristics and severe symptoms that were experienced during a double-blind placebo-controlled food challenge test performed before the patients underwent oral immunotherapy between June 2008 and June 2012. Patients were ≥5 years old and had an anaphylactic history or antigen-specific IgE (>30 kUA/L). Severe symptoms were defined using the grading of the Japanese Anaphylaxis Guidelines, which are modified from the European Academy of Allergology and Clinical Immunology Guidelines.

RESULTS

We evaluated 393 cases with positive test results, including 98 cases with severe symptoms. The most frequent severe symptoms were respiratory (77%), gastrointestinal (28%), cardiovascular (27%), and neurological (13%) symptoms. Multivariate analysis revealed that the significant factors for a severe reaction were a history of anaphylaxis to the causative food (adjusted odds ratio [OR]: 2.147, p = 0.003), older age (per 1 year increase, adjusted OR: 1.102, p = 0.044), and an egg OFC (adjusted OR: 0.433, p = 0.003).

CONCLUSIONS

The risk factors for a severe reaction to OFCs were a history of an anaphylactic reaction and older age. An egg OFC was associated with low risk of severe symptoms during OFC. Therefore, OFCs for patients with these risk factors should only be performed under specialist supervision with access to rapid treatment and full resuscitation equipment.

The Prevalence of Eosinophilic Esophagitis in Pediatric Patients with IgE-Mediated Food Allergy

BACKGROUND

Eosinophilic esophagitis (EoE) is an allergic inflammatory disease that is triggered by food allergens and characterized by progressive esophageal dysfunction. Recently, EoE has been identified in patients who underwent oral immunotherapy (OIT) for IgE-mediated food allergy, suggesting an association.

OBJECTIVE

We sought to ascertain whether significant associations exist between IgE-mediated food allergies and EoE.

METHODS

Using the analysis of electronic medical record data and manual chart review, we examined our subspecialty care network of 35,528 children and adolescents to identify and characterize patients with IgE-mediated and EoE food allergy. The most common food allergens were defined, and the prevalence of EoE in patients with IgE-mediated food allergy was determined. Logistic regression was used to measure the extent to which IgE-mediated food allergy to specific foods is associated with EoE.

RESULTS

The most common causes of EoE were milk, soy, egg, grains, and meats, an allergen pattern that is distinct from that of IgE-mediated food allergy. The prevalence of EoE in patients with IgE-mediated food allergy was higher than that reported in the general population (4.7% vs 0.04%). The distribution of IgE-mediated food allergens in patients with EoE was similar to that of the general population, and IgE-mediated allergy to egg (2.27; 1.91-2.64), milk (4.19; 3.52-4.97), or shellfish (1.55; 1.24-1.92) was significantly associated with an EoE diagnosis.

CONCLUSIONS

Our findings support a clinical association between these conditions that has implications for the management of children with food allergy, and particular relevance to patients undergoing OIT.