Legume and sesame oral food challenge outcomes

Background: Legume and sesame are emerging food allergens. The utility of specific immunoglobulin E (sIgE) testing to predict clinical reactivity to these allergens is not well described. Objective: To describe clinical outcomes and sIgE in sesame and legume oral food challenges (OFC). Methods: We performed a retrospective review of 74 legume and sesame OFCs between 2007 and 2017 at the Ann and Robert H. Lurie Children’s Hospital of Chicago. Clinical data, OFC outcome, and sIgE to legume and sesame were collected. Receiver operating characteristic curves and logistic regression models that predicted OFC outcome were generated. Results: Twenty-eight patients (median age, 6.15 years) passed legume OFC (84.9%), and 25 patients (median age, 5.91 years) passed sesame OFC (61.0%). The median sIgE to legume was 1.41 kUA/L and, to sesame, was 2.34 kUA/L. In patients with failed legume OFC, 60.0% had cutaneous symptoms, 20.0% had gastrointestinal symptoms, and 20.0% had anaphylaxis. Of these reactions, 80.0% were controlled with antihistamine alone and 20.0% required epinephrine. In patients for whom sesame OFC failed, 50.0% had cutaneous symptoms, 12.5% had gastrointestinal symptoms, and 37.50% had anaphylaxis. Of these reactions, 6.3% required epinephrine, 31.3% were controlled with diphenhydramine alone, and 63.50% required additional epinephrine or prednisone. Conclusion: Most OFCs to legumes were passed and reactions to failed legume OFCs were more likely to be nonsevere. Sesame OFC that failed was almost twice as likely compared with legume OFC that failed, and reactions to sesame OFC that failed were often more severe. Sesame sIgE did not correlate with OFC outcome.

Learning early about peanut-triggered food protein‐induced enterocolitis syndrome

Background: Food protein‐induced enterocolitis syndrome (FPIES) is a non-immunoglobulin E mediated food allergy that typically presents with repetitive emesis and may be associated with lethargy, marked pallor, hypotension, hypothermia, and/or diarrhea. Although many foods are known to cause FPIES, peanut-triggered FPIES is emerging due to changes in the feeding practice guidelines, which recommends early peanut introduction in infants. Objective: We aimed to characterize peanut-triggered acute FPIES cases in our pediatric population and to describe their attributes, treatment, and outcomes. We hypothesized that increases in the incidence of peanut-triggered FPIES coincided with implementation of the guidelines for early peanut introduction. Methods: A retrospective chart review was conducted of pediatric patients who presented to Phoenix Children’s Hospital Emergency Department and subspecialty clinics during a 6-year period (January 2013 to September 2019). Results: Thirty-three cases of patients with acute FPIES were identified, five of which were peanut triggered. In those patients with peanut-triggered FPIES, the median age for peanut introduction was 7 months (range, 5‐24 months). Two patients had positive peanut skin-prick test results. All five cases were identified in the past 2 years (2018 to 2019). No peanut-triggered reactions were documented in the preceding 4-year period (2013 to 2017). Conclusion: Peanut may be an emerging trigger of acute FPIES, coinciding with an earlier introduction of peanut in the infant diet after implementation of the new addendum guidelines for the prevention of peanut allergy. Oats and rice were the most common triggers of acute FPIES in our cohort. Further study will help clarify the significance and reproducibility of these findings.

Using oral food challenges to provide clarity and confidence when diagnosing food allergies

A verified food allergy can be an impactful life event that leads to increased anxiety and measurable effects on quality of life. Allergists play a key role in framing this discussion and can help alleviate underlying fears by promoting confidence and clarifying safety concerns. Correctly diagnosing a patient with an immunoglobulin E (IgE) mediated food allergy remains a nuanced process fraught with the potential for error and confusion. This is especially true in situations in which the clinical history is not classic, and allergists rely too heavily on food allergy testing to provide a confirmatory diagnosis. A comprehensive medical history is critical in the diagnosis of food allergy and should be used to determine subsequent testing and interpretation of the results. Oral food challenge (OFC) is a critical procedure to identify patients with an IgE-mediated food allergy when the history and testing are not specific enough to confirm the diagnosis and can be a powerful teaching tool regardless of outcome. Although the safety and feasibility of performing OFC in a busy allergy office have always been a concern, in the hands of an experienced and trained provider, OFC is a safe and reliable procedure for patients of any age. With food allergy rates increasing and analysis of recent data that suggests that allergists across the United States are not providing this resource consistently to their patients, more emphasis needs to be placed on food challenge education and hands-on experience. The demand for OFCs will only continue to increase, especially with the growing popularity of oral immunotherapy programs; therefore, it is essential that allergists become familiar with the merits and limitations of current testing modalities and open their doors to using OFCs in the office.

A formula-fed infant with profound dehydration, cerebral venous sinus thrombosis, and intracranial hemorrhage

Background: Chronic food protein‐induced enterocolitis syndrome (FPIES) is a cell-mediated gastrointestinal food hypersensitivity described almost exclusively in infants fed cow’s milk or soy formula. A timely diagnosis is challenging due to a number of factors, including broad differential diagnoses, absence of specific biomarkers, and delayed symptom onset. Objective: This report aimed to highlight how the severity of presentation can further impede a timely diagnosis in chronic FPIES. Methods: A case of presumed chronic FPIES to soy with previously unreported complications of intracranial hemorrhage and cerebral venous sinus thrombosis was described. Results: We reported a case of a female infant fed a soy formula who presented during the third week of life with intermittent and progressive emesis, diarrhea, and lethargy, which culminated in severe dehydration, with early hospital course complications of seizures, intracranial hemorrhage, and cerebral venous sinus thrombosis. Although not recognized until weeks into the hospital course, many of the presenting symptoms and laboratory abnormalities were characteristic of chronic FPIES. An ultimate consideration of FPIES led to transition to amino acid‐based formula and gradual resolution of gastrointestinal symptoms. Close outpatient follow-up was essential in facilitating subsequent age-appropriate solid food introduction. Conclusion: The severity of presentation in FPIES can represent an additional barrier to a timely diagnosis. Early consideration of this entity in the differential diagnosis of patients with typical FPIES features, regardless of the additional presence of atypical and severe complications, may help with more timely recognition and intervention. In addition, there is an increased need for close follow-up as an outpatient in severe FPIES cases.

Dysregulated specific IgE production to bystander foods in children with peanut allergy but not egg allergy

Background: Food specific immunoglobulin E (sIgE) levels are associated with the development of allergic responses and are used in the clinical evaluation of food allergy. Food sIgG4 levels have been associated with tolerance or clinical nonresponsiveness, particularly in interventional studies. Objective: We aimed to characterize food-specific antibody responses and compare responses with different foods in food allergy. Methods: Serum sIgA, sIgG4, and sIgE to whole peanut, egg white, and wheat, along with total IgE were measured in 57 children. Children with food allergy, children with natural tolerance, and controls were studied. The Mann-Whitney test or Kruskall Wallis test with the Dunn correction were used for statistical analysis. Results: As expected, total IgE levels were highest in the subjects with food allergy compared with the subjects who were nonallergic (p < 0.001) or the subjects who were naturally tolerant (p < 0.001). Peanut sIgE levels were higher in subjects with peanut allergy compared with the subjects who were naturally tolerant (p < 0.0001) and the control subjects (p < 0.03). Interestingly, peanut sIgG4 levels were also highest in children with peanut allergy compared with subjects who were naturally tolerant and control subjects (p = 0.28 and p < 0.001, respectively). Subjects with peanut allergy alone had comparable egg white sIgE levels to children with egg white allergy. In addition, the subjects with peanut allergy alone also had higher levels of egg white and wheat sIgE compared with the control subjects (p < 0.02 and p = 0.001, respectively). In contrast, the subjects with egg white allergy did not demonstrate elevated peanut or wheat sIgE levels. Conclusion: These novel findings suggested that IgE production is dysregulated in patients with peanut allergy, who are much less likely to outgrow their allergy, and suggest that the mechanisms that drive more persistent forms of food allergy may be distinct from more transient forms of food allergy.

Adverse reactions to food additives

Food additives are naturally occurring or synthetic substances that are added to food to modify the color, taste, texture, stability, or other characteristics of foods. These additives are ubiquitous in the food that we consume on a daily basis and, therefore, have been the subject of much scrutiny about possible reactions. Despite these concerns, the overall prevalence of food additive reactions is 1‐2%, with a minority of the wide variety of symptoms attributed to food-additive exposure being reproduced by double-blind placebo controlled challenges. Reactions can be broadly classified into either immunoglobulin E (IgE)- and non‐IgE-mediated reactions, with natural additives accounting for most IgE-mediated reactions, and both natural and synthetic additives being implicated in the non‐IgE-mediated reactions. Reactions that include asthma exacerbations, urticaria and/or angioedema, or anaphylaxis with ingestion of a food additive are most deserving of further allergy evaluation. In this article, we discussed the different types of adverse reactions that have been described to various food additives. We also reviewed the specifics of how to evaluate and diagnose a food additive allergy in a clinic setting.

The impact of food matrices on egg allergenicity

Background: Although many studies show the impact of high and prolonged heating on allergenicity, scarce research exists that examined the impact of the food matrix effect. We presented a case that demonstrates the need for further investigation into this field.Case: An 8-month-old breast-fed girl with a history of moderate eczema presented with concern for food allergy. At 7 months old, she seemed to have difficulty with nursing after consumption of peanut butter, and her pediatrician recommended further avoidance. On presentation to allergy, she had not yet consumed eggs; therefore, skin testing was obtained for both peanut and egg. Her skin testing result to peanut was negative, whereas to egg was elevated at 5/20 mm. To further support clinical decision-making, blood work was obtained, and the egg white specific immunoglobulin E (IgE) value was elevated to 1.33 kU/L. It was recommended to the family to pursue home introduction of peanut and return for oral challenge to baked egg. At 14 months old, the patient returned for oral challenge and successfully tolerated one-half of a muffin. She was discharged with instructions to continue consumption of one-half of a muffin ideally three or more times a week, which the parents reported she continued to tolerate.Conclusion: When the patient was 24 months old, the mother decided, without consultation, to introduce banana-chocolatechip muffins. With the first two ingestions, she developed immediate urticaria. On the third consumption, she developed anaphylaxis, which required epinephrine, with rapid improvement. The patient subsequently returned to regular consumption ofstandard egg muffins (as well as bananas and chocolate individually), which she continued to tolerate. Based on our patient’s ability to tolerate baked egg muffins without banana but significant reaction to baked egg muffins with banana, a potential explanation is that the addition of banana disrupted the egg-wheat matrix. This report points toward a continued need to investigate the role food matrices play on the allergenicity of foods. Furthermore, this case demonstrated the importance of adhering to allergist-prescribed recipes to prevent allergic reactions.

Maternal dietary allergen restriction while breast-feeding: Pediatric resident knowledge and practices

Background: An adequate understanding of the relationship between breast-feeding practices and infant food allergy isessential for clinicians. Although there is evidence of an education gap in general breast-feeding concepts, little is known about the pediatric trainee knowledge and practice with regard to breast-feeding, maternal diet, and potential allergy outcomes.Objective: To assess pediatric residents’ knowledge, describe practices, and evaluate a module designed to provide evidence-based education about breast-feeding, food allergy, and food avoidance to inform future resources on the topic of breastfeeding and allergic outcomes.Methods: Pediatric residents completed a survey to assess the knowledge and comfort with regard to maternal dietaryrestriction, breast-feeding, and infant food allergy. Residents then viewed an online educational module about evidence-basedbreast-feeding and infant food allergy guidelines, and, after 1 month, completed the online questionnaire again.Results: Among respondents (N = 68), only 8% and 5%, felt knowledgeable and comfortable with current maternal diet during breast-feeding and infant food allergy recommendations, respectively. Eighty-seven percent had not received formaltraining on the topic, and a large percentage relied on mentor teaching (49%) or anecdotal evidence (19%) as opposed to available guidelines (32%) for guidance. Most respondents (61–93%) correctly answered questions with regard to guidelines onprimary and secondary food allergy prevention in relation to maternal diet. The upper-level residents answered more questionscorrectly about allergic proctocolitis compared with the interns (p < 0.05); no differences were noted for other topics. The majority (63%) did not believe that a mother’s nutritional status could be adversely affected by dietary allergen restriction. A review of the pre- and posttest scores showed the educational module had little impact on knowledge.Conclusion: Pediatric residents reported low comfort and perceived that they had little knowledge about maternal diet andinfant food allergy, yet their actual performance suggested the opposite. Those who completed the educational module did notdemonstrate knowledge improvement, which highlighted the need for the development of robust educational resources.