Faculty Bibliography

BACKGROUND/UNASSIGNED:Food protein-induced enterocolitis syndrome (FPIES) is a non-immunoglobulin E (IgE) cell mediated food allergy that can cause severe symptoms and is considered an allergic emergency. OBJECTIVE/UNASSIGNED:To describe FPIES epidemiology and appraise the approach to diagnosis and management. METHODS/UNASSIGNED:A review of the relevant articles published in the peer-reviewed journals since the publication of the First International FPIES Consensus Guidelines in 2017. RESULTS/UNASSIGNED:FPIES is estimated to affect 0.51-0.9% of children and 0.22% of adults in the United States. It typically presents with protracted, projectile vomiting, which occurs within 1-4 hours of ingesting culprit foods, sometimes followed by diarrhea within 24 hours of ingestion. In ∼15-20% of severe cases, patients go into hypovolemic or distributive shock. In chronic FPIES, infants may have failure to thrive and weight loss. The most common triggers include cow's milk, oat, rice, and avocado, with egg and peanut being more frequently reported. Examples of other common fruit and vegetable triggers include banana, apple, and sweet potato. FPIES can be classified into acute, chronic, adult-onset, or atypical subtypes. FPIES is associated with comorbid atopic conditions of IgE-mediated food allergy, atopic dermatitis, asthma, allergic rhinitis, and eosinophilic esophagitis. The natural history of infantile FPIES is generally favorable, with the exception of fish FPIES. Seafood FPIES in adults has low rates of resolution over 3-5 years. Correctly identifying FPIES can be challenging because there are no specific biomarkers for diagnosis and the constellation of symptoms may mimic those of infectious enteritis or sepsis. Management relies on dietary food avoidance, periodic re-evaluations for tolerance with oral food challenges, and management of acute reactions with rehydration and antiemetic ondansetron. Although the pathophysiology of FPIES remains poorly understood, underlying mechanisms such as cytokine release, leukocyte activation, and impaired gastrointestinal mucosal barrier function may act as cornerstones for further research. CONCLUSION/UNASSIGNED:Prevention, laboratory diagnostic testing, and strategies to accelerate tolerance development are urgent unmet needs in FPIES.

BACKGROUND:Patients exquisitely sensitive to cashew/pistachio are at risk for allergic reactions to citrus seeds and pectin. OBJECTIVE:In this study, we sought to evaluate whether pectin is contaminated with citrus seeds, to identify a culprit antigen in citrus seeds, and to assess for cross-reactivity among allergens in citrus seeds, citrus pectin, and cashew or pistachio. METHODS:Proteins from orange seed coats, orange seed endosperms, lemon seeds, grapefruit seeds, citrus pectin, apple pectin, and grapefruit pectin were extracted. Protein concentrations in all extracts were determined and visualized using sodium dodecyl sulfate-polyacrylamide gel electrophoresis technique. Immunoglobulin E-binding capacity was determined with Western blot analyses and tandem mass spectrometry for the identification of the culprit allergen in citrus seeds and pectin. RESULTS:In subjects with citrus seed, pectin, and cashew allergies, there was strong immunoglobulin E-reactivity to bands between 17 to 28 kDa and 28 to 38 kDa. The tandem mass spectrometry analysis of these bands indicated the presence of citrin as the culprit allergen. Citrin and Ana o 2 are both 11S globulins belonging to the cupin superfamily, and significant homology was found between these proteins. CONCLUSION/CONCLUSIONS:Citrus pectin may be contaminated with citrus seeds. Citrin, a newly identified allergen in citrus seeds, seems to be the culprit antigen in citrus seeds and contaminated citrus pectin. Citrin is highly homologous with Ana o 2 in cashew and Pis v 2 in pistachio, suggesting potential for cross-reactivity and providing an explanation for co-allergenicity of cashew or pistachio, citrus seeds, and citrus pectin.

BACKGROUND:Epinephrine is the first-line treatment for severe allergic reactions, and rapid treatment is associated with lower rates of hospitalization and death. Current treatment options (epinephrine auto-injectors and manual intramuscular injection) are considered cumbersome, and most patients/caregivers fail to use them, even during severe reactions. An intranasal epinephrine delivery device, neffy, has been designed to provide an additional option for patients/caregivers. OBJECTIVE:We sought to assess the comparative pharmacokinetics and pharmacodynamics of neffy 2.0 mg, EpiPen 0.3 mg, and manual intramuscular injection 0.3 mg. METHODS:This was a phase 1, randomized, 6-treatment, 6-period, 2-part crossover study in 59 healthy subjects. Pharmacokinetic and pharmacodynamic parameters following single and repeat doses of epinephrine were assessed before dosing and at various postdose intervals. RESULTS:The pharmacokinetic profile of neffy was bracketed by approved injection products, with a mean peak plasma level of 481 pg/mL, which fell between EpiPen (753 pg/mL) and epinephrine manual intramuscular injection (339 pg/mL). When dosed both once and twice, neffy resulted in more pronounced increases in pharmacodynamic parameters relative to EpiPen or manual injection. CONCLUSIONS:neffy's pharmacokinetic profile was bracketed by approved injection products, with pharmacodynamic responses that were comparable to or better than approved injection products. neffy is expected to be a safe and effective option, particularly for patients/caregivers who are reluctant to carry and use injection devices.

Guidelines and recommendations for the diagnosis and management of cow's milk allergy (CMA) in childhood are based on scientific review of the available evidence. While this approach is the most rigorous, guidelines may not fully address all scenarios encountered by clinicians. Many symptoms of CMA overlap with other common childhood illnesses and are subjectively reported by the caregivers of the infant, as is the interpretation of the dietary interventions. Additionally, many healthcare professionals and caregivers do not follow the recommendations to perform an oral food challenge or reintroduction of cow's milk after a diagnostic elimination diet because (1) the infant is doing well and (2) the carer's fear of symptoms relapsing with this procedure. As a result, CMA in infants may be either under-diagnosed leading to reduced quality of life for families or over-diagnosed, resulting in unnecessary long-term elimination diets and increasing the risk for nutritional deficiencies. This paper discusses some of these controversial topics, focusing on misdiagnosis and mismanagement in clinical practice. The lack of objective diagnostic criteria can hamper the diagnosis and management of CMA in daily practice.

For food-allergic patients, hypoallergenic formulas (HFs) are medically indicated, often a primary component of the diet and essential for patient safety, health, nutrition, and overall well-being. Yet, food allergy is not included among the conditions mandated for coverage under federal health programs and private health insurance. The 2022 infant formula crisis has affected many North American families and has particularly influenced patients with food allergies who rely on a limited number of safe HF brands to safely meet their nutritional needs for growth and development. The current formula shortage further highlights the longstanding difficulties faced by families with food allergies in accessing HF. Within this context, this article focuses on chronic barriers faced by patients with food allergies in accessing HF and proposes potential solutions. Legislation is desperately needed to address HF affordability through changes in insurance reimbursement and disparities in access to HF among individuals with food allergy.

The diagnosis of cow's milk allergy (CMA) in infants and young children remains a challenge because many of the presenting symptoms are similar to those experienced in other diagnoses. Both over- and under-diagnosis occur frequently. Misdiagnosis carries allergic and nutritional risks, including acute reactions, growth faltering, micronutrient deficiencies and a diminished quality of life for infants and caregivers. An inappropriate diagnosis may also add a financial burden on families and on the healthcare system. Elimination and reintroduction of cow's milk (CM) and its derivatives is essential for diagnosing CMA as well as inducing tolerance to CM. In non-IgE mediated CMA, the diagnostic elimination diet typically requires 2-4 weeks before reintroduction, while for IgE mediated allergy the time window may be shorter (1-2 weeks). An oral food challenge (OFC) under medical supervision remains the most reliable diagnostic method for IgE mediated and more severe types of non-IgE mediated CMA such as food protein induced enterocolitis syndrome (FPIES). Conversely, for other forms of non-IgE mediated CMA, reintroduction can be performed at home. The OFC cannot be replaced by the milk ladder after a diagnostic elimination diet. The duration of the therapeutic elimination diet, once a diagnosis was confirmed, can only be established through testing changes in sensitization status, OFCs or home reintroduction, which are directed by local protocols and services' availability. Prior non-evidence-based recommendations suggest that the first therapeutic elimination diet should last for at least 6 months or up to the age of 9-12 months, whichever is reached first. After a therapeutic elimination diet, a milk-ladder approach can be used for non-IgE mediated allergies to determine tolerance. Whilst some centers use the milk ladder also for IgE mediated allergies, there are concerns about the risk of having immediate-type reactions at home. Milk ladders have been adapted to local dietary habits, and typically start with small amounts of baked milk which then step up in the ladder to less heated and fermented foods, increasing the allergenicity. This publication aims to narratively review the risks associated with under- and over-diagnosis of CMA, therefore stressing the necessity of an appropriate diagnosis and management.