Food protein-induced enterocolitis syndrome: epidemiology and comorbidities

Current status and future directions in food protein-induced enterocolitis syndrome: An NIAID workshop report of the June 22, 2022, virtual meeting

Food protein-induced enterocolitis syndrome (FPIES) is a non-IgE-mediated gastrointestinal food allergy characterized by delayed, protracted vomiting and accompanied by lethargy and pallor, usually 1 to 4 hours after ingesting the food allergen. The pathophysiology of FPIES remains unknown, and currently there are no diagnostic biomarkers available to assess disease activity or its resolution. Over the last 2 decades, FPIES has become increasingly recognized in both pediatric and adult patients. Forty years after the initial FPIES description, the first FPIES code appeared in the International Classification of Diseases, Tenth Revision (ICD-10), and the first international consensus guidelines for the diagnosis and management of FPIES were published. On June 22, 2022, the National Institute of Allergy and Infectious Diseases (NIAID) held its first virtual multidisciplinary workshop on FPIES. Various clinical and translational aspects of FPIES as well as important areas of unmet needs were discussed as priorities for future research during this 2-day virtual workshop. Our report provides a summary of content of the workshop, including updated literature on the topic areas, and also provides critical commentary on the state of FPIES.

The epidemiology of food allergy in adults

The prevalence and awareness of food allergy (FA) among US adults is arguably at a historical high, both with respect to primary immunoglobulin E-mediated food hypersensitivity and other food-triggered conditions that operate through a variety of immunologic mechanisms (eg, pollen-FA syndrome, alpha-gal syndrome, food protein-induced enterocolitis syndrome, eosinophilic esophagitis). Worryingly, not only are many adults retaining childhood-onset food allergies as they age into adulthood, it seems that many adults are experiencing adult-onset allergies to previously tolerated foods, with correspondingly adverse physical, and psychological health impacts. Consequently, this review aims to summarize what is currently known about the epidemiology and population-level burden of FA among adult populations in North America and around the globe. This article also provides insights into the natural history of these conditions and what we need to know as we look to the future to support effective care and prevent FA.

Update on Food Protein-Induced Enterocolitis Syndrome (FPIES)

PURPOSE OF REVIEW

Food protein-induced enterocolitis syndrome (FPIES) is a non-IgE-mediated food allergy characterized by delayed, and potentially severe, gastrointestinal symptoms. Since the advent of a specific diagnostic code and establishment of diagnostic guidelines, our understanding of this condition has grown.

RECENT FINDINGS

FPIES affects patients from early infancy into adulthood. Any food can be a trigger, and common culprit foods vary geographically and by age. An understanding of the complex underlying immune mechanisms remains elusive, although studies show pan-leukocyte activation, cytokine release, and increased gastrointestinal permeability. Management involves trigger avoidance, and patients may benefit from the support of a dietitian to ensure adequate nutrient intake. Tolerance develops over time for most children, but due to the risk of severe symptoms, re-introduction of a suspected FPIES trigger is recommended only under supervision at an oral food challenge. Studies continue to evaluate the optimal challenge protocol. Caregivers of children with FPIES report high levels of anxiety and stress, which is attributed to the dramatic symptomatology, dietary restrictions, nutritional concerns, lack of confirmatory diagnostic tests, and limited tools for management of reactions. Our understanding of the FPIES diagnosis has improved over the last few decades, but there remain opportunities, particularly regarding discerning the pathophysiology and best management practices.

Pathophysiology of Non-IgE-Mediated Food Allergy

Non-IgE-mediated food allergies are a group of disorders characterized by subacute or chronic inflammatory processes in the gut. Unlike IgE mediated food allergies that may result in multi-organ system anaphylaxis, the non-IgE mediated food allergies primarily affect the gastrointestinal tract. This review outlines the clinical manifestations, epidemiology, pathophysiology, and management of non-IgE-mediated food allergies. An updated literature search of selected non-IgE-mediated food allergies was conducted for this review using PubMed database to the current year (2021). Reviewed disorders include food protein-induced enterocolitis syndrome (FPIES), food-protein enteropathy (FPE), food protein-induced allergic proctocolitis (FPIAP), and eosinophilic gastrointestinal disorders (EGIDs) such as eosinophilic esophagitis (EoE). While extensive gains have been made in understanding FPIES, FPIAP, FPE, and EoE, more information is needed on the pathophysiology of these food allergies. Similarities among them include involvement of innate immunity, T-lymphocyte processes, alteration of the intestinal lumen at the cellular level with the appearance of inflammatory cells and associated histologic changes, and specific cytokine profiles suggesting food-specific, T-cell, and immune-mediated responses. While FPIES and FPIAP typically resolve in early childhood, EGIDs typically do not. Emerging new therapies for EoE offer promise of additional treatment options. Further studies identifying the immunopathogenesis, associated biomarkers, and mechanisms of tolerance are needed to inform prevention, diagnosis and management.

Alternative Fish Species for Nutritional Management of Children with Fish-FPIES—A Clinical Approach

In the Mediterranean region, fish is a common cause of food protein-induced enterocolitis syndrome (FPIES) in children. No laboratory tests specific to FPIES are available, and oral food challenge (OFC) is the gold standard for its diagnosis and testing for achievement of tolerance. Children with FPIES to fish are usually advised to avoid all fish, regardless of the species. Fish are typically classified into bony and cartilaginous, which are phylogenetically distant species and therefore contain less cross-reacting allergens. The protein β-parvalbumin, considered a pan-allergenic, is found in bony fish, while the non-allergenic α-parvalbumin is commonly found in cartilaginous fish. Based on this difference, as a first step in the therapeutic process of children with FPIES caused by a certain fish in the bony fish category (i.e., hake, cod, perch, sardine, gilthead sea bream, red mullet, sole, megrim, sea bass, anchovy, tuna, swordfish, trout, etc.), an OFC to an alternative from the category of cartilaginous fish is suggested (i.e., blue shark, tope shark, dogfish, monkfish, skate, and ray) and vice versa. Regarding the increased mercury content in some sharks and other large species, the maximum limit imposed by the European Food Safety Authority (EFSA) for weekly mercury intake must be considered. An algorithm for the management of fish-FPIES, including alternative fish species, is proposed.

The evolution of food protein-induced enterocolitis syndrome: From a diagnosis that did not exist to a condition in need of answers

OBJECTIVE

Although food protein-induced enterocolitis syndrome (FPIES) was first described approximately 50 years ago and research is increasing, there are still considerable unmet needs in FPIES. This article catalogs the areas of progress and areas for further research.

DATA SOURCES

Through our personal experiences in caring for patients with FPIES, our personal research, and a review of the existing FPIES literature as indexed in PubMed, we explored what is known and what is needed in FPIES.

STUDY SELECTIONS

The studies that have improved the knowledge of FPIES, defined phenotypes, allowed for better-informed management of FPIES, and laid the groundwork for further research.

RESULTS

Further research is needed in the areas of prevalence, natural history, trigger foods, threshold doses, how and when to perform oral food challenges, and immunopathogenesis of this disorder. Development of a biomarker and determination of the best method to treat reactions is also needed. Furthermore, FPIES has a substantial psychosocial and economic impact on families, and more research is needed in developing and implementing ameliorating strategies.

CONCLUSION

By partnering together, health care providers, advocacy organizations, and families can continue to advance our understanding and improve the care of patients and families living with FPIES.

Allergy and immunology in young children of Japan: The JECS cohort

BACKGROUND

Capturing epidemiological signatures is essential to document burdens of disease and to design health care services, including prevention measures, clinical interventions, and policies. There are large geographical and ethnic variations in the epidemiology of allergic and immunological diseases. Various data are available from North America and Europe, but the epidemiology of allergic and immunological diseases in Asia is not well documented.

OBJECTIVE

To characterize epidemiological signatures of allergic and immunological disease in young children in Japan.

METHODS

This was a national, multicenter, prospective birth cohort study: Japan Environment and Children's Study (JECS). A general population of 103,060 women was enrolled during pregnancy. Allergic and immunological outcomes were assessed among young children using questionnaire data.

RESULTS

The prevalence of caregiver-reported immediate food allergy was 7.6%, 6.7%, and 4.9% at age 1, 2, and 3 years, respectively. Hen egg allergy was most common (5.4% prevalence at age 1 year) followed by allergies to cow milk and wheat. Several patterns of allergic symptom clusters were identified. Physician diagnosed, as reported by the caregiver, non-IgE mediated gastrointestinal food allergy affected 0.5% of infants. By contrast, caregiver-reported gastrointestinal food allergies affected 1.4% of children. Kawasaki disease affected 0.3% and 0.4% children, respectively, at age 1 and 3 years. Primary immunodeficiency disorders affected 0.005% children at age 3 years.

CONCLUSION

These data provide important epidemiological signatures of allergy and immunology in young Japanese children including the age-specific prevalence of allergic disease, Kawasaki disease, and primary immune deficiency.