The prevalence and natural course of food protein–induced enterocolitis syndrome to cow’s milk: A large-scale, prospective population-based study

IL10 and CXCL10 mRNA expression in food protein-induced enterocolitis syndrome

BACKGROUND

Food protein-induced enterocolitis syndrome (FPIES) is a rare non-IgE-mediated food allergy that mainly impacts babies and 7toddlers. The exact mechanism of FPIES is not completely understood. By studying the expression of IL-10 and CXCL10 in pediatric FPIES patients, researchers can gain insights into the immune mechanisms underlying this disorder.

METHODS

Peripheral venous blood was collected and subsequently stabilized with RNA pro. Total RNA was extracted and mRNA levels of CXCL10 and IL-10 was determined with real time PCR.

RESULTS

Children with FPIES had significantly higher values than the healthy control group (HC) for CXCL10 while FPIES had a significant lower values than the control group for IL-10.

CONCLUSIONS

Our results show a high production of CXCL10 and a concomitant reduced production of IL-10 in FPIES subjects who have not yet reached tolerance. These data may represent a molecular diagnostic marker for FPIES.

Human milk oligosaccharides in preventing food allergy: A review through gut microbiota and immune regulation

Food allergy (FA) has increasingly attracted global attention in past decades. However, the mechanism and effect of FA are complex and varied, rendering it hard to prevention and management. Most of the allergens identified so far are macromolecular proteins in food and may have potential cross-reactions. Human milk oligosaccharides (HMOs) have been regarded as an ideal nutrient component for infants, as they can enhance the immunomodulatory capacity to inhibit the progress of FA. HMOs may intervene in the development of allergies by modifying gut microbiota and increasing specific short-chain fatty acids levels. Additionally, HMOs could improve the intestinal permeability and directly or indirectly regulate the balance of T helper cells and regulatory T cells by enhancing the inflammatory signaling pathways to combat FA. This review will discuss the influence factors of FA, key species of gut microbiota involved in FA, types of FA, and profiles of HMOs and provide evidence for future research trends to advance HMOs as potential therapeutic aids in preventing the progress of FA.

Clinical-Hematological Changes and Predictors of Severity in Acute Food Protein-Induced Enterocolitis Syndrome Reactions at Oral Food Challenge: A Multicenter Observational Study

BACKGROUND

Oral food challenge (OFC) is the criterion standard for diagnosis of acute food protein-induced enterocolitis syndrome (FPIES). No diagnostic/prognostic biomarkers are available, and OFC assessment criteria are not validated.

OBJECTIVE

To assess clinical-hematological changes and predictors of severity of FPIES reactions at OFC.

METHODS

This was an observational multicenter prospective study. Children aged 0 to 18 years diagnosed with acute FPIES were recruited at follow-up OFC in 12 tertiary centers in Spain and Italy. OFC outcomes (as positive/negative/inconclusive and mild/moderate/severe) were assessed on the basis of published "2017 FPIES Consensus" criteria. Clinical characteristics were recorded, and full blood cell count was done at baseline, reaction onset, and 4 hours later. Regression analysis was performed to assess predictors of severe reactions at OFC.

RESULTS

A total of 81 children had positive OFC (mild in 11% [9 of 81], moderate in 61% [49 of 81], and severe in 28% [23 of 81]). Increase in neutrophils and reduction in eosinophils, basophils, and lymphocytes were observed (P < .05). OFC was inconclusive in 19 cases despite objective signs or neutrophilia. Regression analysis showed that a 2-day OFC protocol where only 25% of an age-appropriate portion is given on day 1 (not sex, age, culprit food, cumulative dose, and previous reaction severity) was associated with reduced odds of severe reaction compared with giving multiple doses in a single day.

CONCLUSIONS

Distinct hematological changes may help support FPIES diagnosis. Current OFC assessment criteria may not capture the broad spectrum of acute FPIES presentations. This 2-day protocol may be associated with a reduced risk of severe reactions. Future work should aim to develop safer OFC and non-OFC diagnostics for FPIES.

A Second Slice of FPIES: A Single-Center Reappraisal of Pediatric FPIES

BACKGROUND

Food protein-induced enterocolitis syndrome (FPIES) is being increasingly recognized as a non-IgE-mediated food allergy; however, it remains unclear if and how the presentation, diagnosis, and management of this disease has changed in recent years.

OBJECTIVE

To reappraise the FPIES cohort at a large US pediatric tertiary referral center.

METHODS

We performed a retrospective chart review of pediatric patients with FPIES (International Classification of Diseases, Tenth Revision code K52.21) diagnosed in our allergy/immunology clinics between 2018 and 2022.

RESULTS

There were 210 children diagnosed with FPIES. Most were White (73.8%), non-Hispanic (71.4%), and male (54.3%) with private insurance (77.6%). Cow's milk was the most common food trigger (35.2%), with the earliest median age of onset of 5 months. The atypical FPIES rate was 13.8%. FPIES was accurately diagnosed in 54.3% at the first medical contact. The oral food challenge pass rate was 73.5%. The rate of trigger resolution at 36 months was 77%.

CONCLUSIONS

By comparing trends from a previous and current FPIES cohort, we were able to assess the potential impact of various guidelines and practice changes on the diagnosis and management of FPIES at our center. Milk and oat surpassed rice as the most common FPIES triggers; peanut and egg emerged as new FPIES triggers; there was a shorter time to diagnosis and an increased rate of atypical FPIES. Our findings reflect earlier recognition of FPIES and prompt allergy/immunology referral from community physicians, implementation of recent medical society guidelines for infant feeding practices, and growing clinical expertise of allergists at our center.

Resolution of Food Protein-Induced Enterocolitis Syndrome-A Long-Term Follow-Up Study of 113 Swedish Children

BACKGROUND

Food protein-induced enterocolitis syndrome (FPIES), a non-IgE-mediated allergy, primarily affects infants and young children. Whether and when tolerance develops seems to vary among populations and trigger foods.

OBJECTIVE

This study aimed to evaluate tolerance development and its assessment in a Swedish cohort.

METHODS

This was a prospective follow-up study of a Swedish cohort of 113 children, followed at 25 pediatric departments, with acute FPIES. Data on oral food challenges and FPIES resolution were collected through chart reviews and, if incomplete, supplemental caregiver interviews.

RESULTS

The median age at last follow-up was 5.6 years (range: 8.7 months to 16.5 years). Eighty-three children (73%) developed tolerance to 96 of 137 (70%) foods: 93% for cow's milk, 92% for oat, and 46% for fish. The median age when tolerance was developed was 36.0 months (interquartile range: 23.7-48.2 months): 24.4 months for cow's milk, 30.1 months for oat, and 49.4 months for fish. Tolerance was determined in hospital in 45% of cases. Five percent demonstrated allergic sensitization to their FPIES trigger food. Age at tolerance development did not differ between sensitized and nonsensitized patients.

CONCLUSIONS

Most of the children in this Swedish cohort with FPIES achieved tolerance before age 4 years. Cow's milk- and oat-induced FPIES had similar remission patterns, with early resolution. Development of tolerance to fish occurred significantly later compared with all other FPIES-inducing foods.

Gut microbiota in infants with food protein enterocolitis

BACKGROUND

We explored the effects of two formulas, extensively hydrolyzed formula (EHF) and amino acid-based formula (AAF), on the gut microbiota and short-chain fatty acids (SCFAs) in infants with food protein-induced enterocolitis syndrome (FPIES).

METHODS

Fecal samples of thirty infants with bloody diarrhea receiving EHF or AAF feeding were collected at enrollment, diagnosis of FPIES, and four weeks after diagnosis. The gut microbiota and SCFAs were analyzed using 16 S rRNA gene sequencing and gas chromatography-mass spectrometry, respectively.

RESULTS

Microbial diversity of FPIES infants was significantly different from that of the controls. FPIES infants had a significantly lower abundance of Bifidobacterium and a higher level of hexanoic acid compared with controls. In EHF-fed FPIES infants, microbial richness was significantly decreased over time; while the microbial diversity and richness in AAF-fed FPIES infants exhibited no differences at the three time points. By four weeks after diagnosis, EHF-fed FPIES infants contained a decreased abundance of Acinetobacter, whereas AAF-fed FPIES infants contained an increased abundance of Escherichia-Shigella. EHF-fed infants experienced significantly decreased levels of butyric acid and hexanoic acid at four weeks after diagnosis.

CONCLUSIONS

Infants with FPIES had intestinal dysbiosis and different formulas differentially affected gut microbiota and SCFAs in FPIES infants.

IMPACT

We firstly report the impacts of two different nutritional milk formulas on the gut microbial composition and SCFAs levels in infants with FPIES. We show that infants with FPIES have obvious intestinal dysbiosis and different formulas differentially affect gut microbiota and SCFAs in FPIES infants. Understanding the effects of different types of formulas on gut microbial colonization and composition, as well as the related metabolites in infants with FPIES could help provide valuable insights for making choices about feeding practices.

Prevalence and risk factors for milk allergy overdiagnosis in the BEEP trial cohort

BACKGROUND

Cow's milk allergy (CMA) overdiagnosis in young children appears to be increasing and has not been well characterised. We used a clinical trial population to characterise CMA overdiagnosis and identify individual-level and primary care practice-level risk factors.

METHODS

We analysed data from 1394 children born in England in 2014-2016 (BEEP trial, ISRCTN21528841). Participants underwent formal CMA diagnosis at ≤2 years. CMA overdiagnosis was defined in three separate ways: parent-reported milk reaction; primary care record of milk hypersensitivity symptoms; and primary care record of low-allergy formula prescription.

RESULTS

CMA was formally diagnosed in 19 (1.4%) participants. CMA overdiagnosis was common: 16.1% had parent-reported cow's milk hypersensitivity, 11.3% primary care recorded milk hypersensitivity and 8.7% had low-allergy formula prescription. Symptoms attributed to cow's milk hypersensitivity in participants without CMA were commonly gastrointestinal and reported from a median age of 49 days. Low-allergy formula prescriptions in participants without CMA lasted a median of 10 months (interquartile range 1, 16); the estimated volume consumed was a median of 272 litres (26, 448). Risk factors for CMA overdiagnosis were high practice-based low-allergy formula prescribing in the previous year and maternal report of antibiotic prescription during pregnancy. Exclusive formula feeding from birth was associated with increased low-allergy formula prescription. There was no evidence that practice prescribing of paediatric adrenaline auto-injectors or anti-reflux medications, or maternal features such as anxiety, age, parity and socioeconomic status were associated with CMA overdiagnosis.

CONCLUSION

CMA overdiagnosis is common in early infancy. Risk factors include high primary care practice-based low-allergy formula prescribing and maternal report of antibiotic prescription during pregnancy.

Shift from Cow's Milk Food Protein-Induced Enterocolitis Syndrome to IgE-Mediated Allergy: Case Series and Literature Review

Background: Food protein-induced enterocolitis syndrome (FPIES) is a non-IgE-mediated food allergy characterized by gastrointestinal symptom onset within 1-4 hours from trigger food ingestion. In the literature, some authors have previously described the possibility that a patient with FPIES may develop an IgE-mediated allergy to the same trigger food, especially cow's milk (CM). Case Presentation: We reported five cases of CM-FPIES converting to IgE-mediated CM allergy presented at our tertiary pediatric Allergy Unit and performed a review of the literature, aiming to characterize the clinical features of patients who are at risk of developing such conversion. Conclusions: This phenomenon raises the question of whether IgE-mediated and non-IgE-mediated allergies represent a spectrum of the same disease and highlights the need for further investigation to understand the pathophysiological mechanisms of this process.

Current and future perspectives on the consensus guideline for food protein-induced enterocolitis syndrome (FPIES)

Food protein-induced enterocolitis syndrome (FPIES) is a non-IgE mediated food allergy presenting with delayed onset of projectile vomiting in the absence of cutaneous and respiratory symptoms. The pathophysiology of FPIES remains poorly characterized. The first international consensus guidelines for FPIES were published in 2017 and provided clinicians with parameters on the diagnosis and treatment of FPIES. The guidelines have served as a resource in the recognition and management of FPIES, contributing to an increased awareness of FPIES. Since then, new evidence has emerged, shedding light on adult-onset FPIES, the different phenotypes of FPIES, the recognition of new food triggers, center-specific food challenge protocols and management of acute FPIES. Emerging evidence indicates that FPIES impacts both pediatric and adult population. As a result, there is growing need to tailor the consensus guidelines to capture diagnoses in both patient groups. Furthermore, it is crucial to provide food challenge protocols that meet the needs of both pediatric and adult FPIES patients, as well as the subset of patients with atypical FPIES. This review highlights the evolving clinical evidence relating to FPIES diagnosis and management published since the 2017 International FPIES Guidelines. We will focus on areas where recent published evidence may support evolution or revision of the guidelines.

Sociodemographic inequities in food allergy: Insights on food allergy from birth cohorts

A large and growing corpus of epidemiologic studies suggests that the population-level burden of pediatric FA is not equitably distributed across major sociodemographic groups, including race, ethnicity, household income, parental educational attainment, and sex. As is the case for more extensively studied allergic disease states such as asthma and atopic dermatitis epidemiologic data suggest that FA may be more prevalent among certain populations experiencing lower socioeconomic status (SES), particularly those with specific racial and ethnic minority backgrounds living in highly urbanized regions. Emerging data also indicate that these patients may also experience more severe FA-related physical health, psychosocial, and economic outcomes relating to chronic disease management. However, many studies that have identified sociodemographic inequities in FA burden are limited by cross-sectional designs that are subject to numerous biases. Compared with cross-sectional study designs or cohorts established later in life, birth cohorts offer advantages relative to other study designs when investigators seek to understand causal relationships between exposures occurring during the prenatal or postnatal period and the atopic disease status of individuals later in life. Numerous birth cohorts have been established across recent decades, which include evaluation of food allergy-related outcomes, and a subset of these also have measured sociodemographic variables that, together, have the potential to shed light on the existence and possible etiology of sociodemographic inequities in food allergy. This manuscript reports the findings of a comprehensive survey of the current state of this birth cohort literature and draws insights into what is currently known, and what further information can potentially be gleaned from thoughtful examination and further follow-up of ongoing birth cohorts across the globe.

A nationwide survey of non-IgE-mediated gastrointestinal food allergies in neonates and infants

BACKGROUND

Non-IgE-mediated gastrointestinal food allergies (non-IgE-GIFAs) seem to be increasing rapidly worldwide. However, nationwide studies have been limited to food-protein-induced enterocolitis (FPIES) and food-protein-induced allergic proctocolitis (FPIAP), with little attention to other non-IgE-GIFA subgroups. The aim of this study was to elucidate the clinical features of all patients with non-IgE-GIFAs, not just certain subgroups.

METHODS

We conducted a nationwide cross-sectional survey of non-IgE-GIFAs in Japan from April 2015 through March 2016. A questionnaire was sent to hospitals and clinics throughout Japan. The questionnaire asked about the number of physician-diagnosed non-IgE-GIFA patients, the status of fulfillment of the diagnostic criteria, tentative classification into 4 clusters based on the initial symptoms, the day of onset after birth, complications, and the suspected offending food(s).

RESULTS

The response rate to that questionnaire was 67.6% from hospitals and 47.4% from clinics. Analyses were conducted about "diagnosis-probable" patient cohort (n = 402) and the "diagnosis-confirmed" patients (n = 80). In half of the reported non-IgE-GIFA patients, onset occurred in the neonatal period. The patients were evenly distributed among 4 non-IgE-GIFA clusters. In Cluster 1, with symptoms of vomiting and bloody stool, the onset showed a median of 7 days after birth, which was the earliest among the clusters. Cow's milk was the most common causative food.

CONCLUSIONS

In half of the patients, the onset of non-IgE-GIFAs was in the neonatal period. This highlights the importance of studying the pathogenesis in the fetal and neonatal periods.

Heterogeneity of food protein-induced enterocolitis syndrome (FPIES)

Food protein-induced enterocolitis syndrome (FPIES) is a non-IgE-mediated food allergy with gastrointestinal symptoms such as vomiting and diarrhea. The development of international consensus guidelines for the diagnosis and management of FPIES in 2017 enabled us to compare patients worldwide, regardless of geographic variation in disease features. As a result, it has become clear that there is heterogeneity among patients with FPIES or that there are cases that partly fit the diagnostic criteria for FPIES but have different characteristics. This review highlights the heterogeneity in FPIES characteristics in terms of trigger foods, the age of onset, differences in geographic regions, and symptoms; it further proposes four disease entities, including acute FPIES in children, acute FPIES in adults, chronic FPIES, and early-onset neonatal FPIES, depending on the age of onset and presumed pathophysiology. The major symptoms at onset and trigger foods differ in acute FPIES in children, acute FPIES in adults, and chronic FPIES, whereas the disease entities may share a similar pathophysiology. Early-onset neonatal FPIES may have a different pathophysiology than acute or chronic FPIES, and may not necessarily fulfil the full diagnostic criteria for acute or chronic FPIES described in the international consensus guidelines. Due to the similarity in symptoms, early-onset neonatal FPIES may sometimes be misdiagnosed as necrotizing enterocolitis. We aim to increase awareness of FPIES among medical staff in pediatrics, neonatology, and internal medicine and promote research, to gain a better understanding of the heterogeneity and pathophysiology of FPIES.

Dietary management of IgE and non-IgE-mediated food allergies in pediatric patients

Food allergies (FA) consist of both IgE and non-IgE-mediated entities, with varying phenotypes and overlapping and different considerations for each specific disease presentation. In general, all FAs place children at increased risk for inadequate nutritional intake and negative impacts on their nutritional status, as well as negative impacts on the quality of life for the entire family. To minimize these untoward effects, a multidisciplinary approach should be taken, including consultation and management with a dietitian trained in the varying presentations of FA. Families should be instructed on label reading as a first line of nutritional management. During a nutrition consultation, the age of the child, growth, and nutritional status should be considered. Food refusal should be assessed and addressed. Families should be educated on avoidance and appropriate substitutions. In the case of cow's milk allergy, a suitable specialized formula should be suggested if the infant is not breastfed or if breast milk supply is not sufficient. Other mammalian milk should be avoided and careful consideration should be given before plant-based milk is used in young children. Specific food allergies may differ in terms of advice provided on the level of avoidance required, whether precautionary advisory labels should be avoided, and if a maternal avoidance of the allergen during breastfeeding should be advised. The role of immunonutrition on overall health should be discussed.

An ESPGHAN Position Paper on the Diagnosis, Management, and Prevention of Cow's Milk Allergy

A previous guideline on cow's milk allergy (CMA) developed by the European Society of Paediatric Gastroenterology, Hepatology and Nutrition (ESPGHAN) was published in 2012. This position paper provides an update on the diagnosis, treatment, and prevention of CMA with focus on gastrointestinal manifestations. All systematic reviews and meta-analyses regarding prevalence, pathophysiology, symptoms, and diagnosis of CMA published after the previous ESPGHAN document were considered. Medline was searched from inception until May 2022 for topics that were not covered in the previous document. After reaching consensus on the manuscript, statements were formulated and voted on each of them with a score between 0 and 9. A score of ≥6 was arbitrarily considered as agreement. Available evidence on the role of dietary practice in the prevention, diagnosis, and management of CMA was updated and recommendations formulated. CMA in exclusively breastfed infants exists, but is uncommon and suffers from over-diagnosis. CMA is also over-diagnosed in formula and mixed fed infants. Changes in stool characteristics, feeding aversion, or occasional spots of blood in stool are common and in general should not be considered as diagnostic of CMA, irrespective of preceding consumption of cow's milk. Over-diagnosis of CMA occurs much more frequently than under-diagnosis; both have potentially harmful consequences. Therefore, the necessity of a challenge test after a short diagnostic elimination diet of 2-4 weeks is recommended as the cornerstone of the diagnosis. This position paper contains sections on nutrition, growth, cost, and quality of life.

[Differential diagnosis in food allergy]

It is important to establish the differential diagnosis of food allergy with other disorders, for example: toxic reactions that occur in any person exposed to a sufficient amount of some allergen, and non-toxic reactions that depend on individual susceptibility (food allergy or intolerance). The differential diagnosis is decisive to establish the appropriate treatment. Food intolerance involves adverse reactions to foods without any immunological response involved, and commonly manifests with gastrointestinal symptoms (malaise, abdominal pain or diarrhea). Food allergy is an exaggerated reaction of the immune system, often mediated by IgE, that can trigger serious symptoms (hives, inflammation, respiratory distress, even anaphylaxis). The complex thing is because the symptoms sometimes overlap. To establish an accurate diagnosis, exhaustive clinical evaluation, laboratory tests and, in some cases, controlled provocation tests are required. It is important to understand these distinctions, because treatment and management vary significantly. Food intolerance involves the elimination or reduction of the food that triggers the allergic reaction and requires rigorous measures (complete avoidance of the allergen and availability of epinephrine in cases of severe reactions).

[Non-IgE-mediated food allergy]

Food allergy is an immune response to proteins in food. It usually affects 8% of children and 2% of adults in Western countries. Non-IgE-mediated food allergy mainly affects the gastrointestinal tract. Gastrointestinal food allergies are classified, by their underlying pathogenesis, as: IgE-mediated, non-IgE-mediated, or mixed. The symptoms of patients with food protein-induced allergic proctocolitis originate from local inflammation of the distal colon, which causes hematochezia in neonates. It can affect the entire gastrointestinal tract and cause symptoms of intractable emesis, with subsequent metabolic disorders and hypovolemic shock. Food protein-induced enterocolitis syndrome is a non-IgE-mediated allergy that usually appears in childhood, with prolonged repetitive vomiting, starting 1 to 4 hours after ingestion of food. The manifestation in adults is usually triggered by the consumption of shellfish. Atopic diseases affect 40-60% of patients with food protein- induced enterocolitis syndrome, including 40-50% of those with food protein-induced enteropathy and proctocolitis. Probiotics (Lactobacillus GG) can alleviate the symptoms of allergic proctocolitis induced by food proteins, by altering the composition of the intestinal microbiota. Fecal microbiota transplantation (FMT) can change intestinal microecology efficiently compared to food or probiotics.

Food protein-induced enterocolitis syndrome (FPIES): Beyond the guidelines

Background

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

To describe FPIES epidemiology and appraise the approach to diagnosis and management.

Methods

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

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

Prevention, laboratory diagnostic testing, and strategies to accelerate tolerance development are urgent unmet needs in FPIES.

World Allergy Organization (WAO) Diagnosis and Rationale for Action against Cow's Milk Allergy (DRACMA) guidelines update - X - Breastfeeding a baby with cow's milk allergy

Cow's milk allergy is rare in exclusively breastfed infants. To support the continuation of breastfeeding an infant after diagnosis with a cow's milk allergy, it is critical to examine the evidence for and against any form of cow's milk elimination diet for lactating mothers. In this narrative review, we highlight the lack of high-quality evidence, hence subsequent controversy, regarding whether the minuscule quantities of cow's milk proteins detectable in human milk cause infant cow's milk allergy symptoms. Current clinical practice recommendations advise a 2-4 week trial of maternal cow's milk dietary elimination for: a) IgE-mediated cow's milk allergy only if the infant is symptomatic on breastfeeding alone; b) non-IgE-mediated associated symptoms only if the history and examination strongly suggest cow's milk allergy; and c) infants with moderate to severe eczema/atopic dermatitis, unresponsive to topical steroids and sensitized to cow's milk protein. There should be a clear plan for home reintroduction of cow's milk into the maternal diet for a period of 1 week to determine that the cow's milk elimination is responsible for resolution of symptoms, and then subsequent reoccurrence of infant symptoms upon maternal cow's milk reintroduction. The evidence base to support the use of maternal cow's milk avoidance for the treatment of a breastfed infant with cow's milk allergy is of limited strength due to a lack of high-quality, adequately powered, randomised controlled trials. It is important to consider the consequences of maternal cow's milk avoidance on reducing immune enhancing factors in breast milk, as well as the potential nutritional and quality of life impacts on the mother. Referral to a dietitian is advised for dietary education, along with calcium and vitamin D supplementation according to local recommendations, and a maternal substitute milk should be advised. However, for most breastfed infants with cow's milk allergy maternal cow's milk dietary elimination will not be required, and active support of the mother to continue breastfeeding is essential.

Australian Infant Food Allergy Emergency Presentations Following Updated Early Food Introduction Guidelines

BACKGROUND

The Australasian Society of Clinical Immunology and Allergy food allergy prevention guidelines were updated in 2016 to recommend home introduction of allergenic foods actively in the first year of life, including to infants at high risk of allergy. An important consideration for parents and providers is whether this practice increases food allergy reactions or anaphylaxis.

OBJECTIVE

We aimed to determine whether the 2016 update of food allergy prevention guidelines was associated with an increase in food allergy or anaphylaxis emergency department (ED) presentations.

METHODS

We obtained hospital electronic medical records for infants aged 4 to 12 months who attended the Royal Children's Hospital Melbourne ED in 2015 or in 2018 with a presenting problem or an encounter diagnosis of food allergy or anaphylaxis.

RESULTS

Emergency department presentations owing to food allergy increased from 1.0% (95% CI, 0.85-1.23) in 2015 to 1.4% (95% CI, 1.22-1.67) in 2018 (P = .006). There was no increase in the number of anaphylaxis presentations (28 in 2015 and 22 in 2018) or peanut anaphylaxis presentations (three in 2015 and three in 2018). Overall, the proportion of food allergy presentations attributed to IgE-mediated food allergy was similar (82.1% in 2015 and 84.1% in 2018), whereas peanut allergy presentations increased slightly, although not statically significantly, from 14.6% to 21.2% (P = .09). Food protein-induced enterocolitis syndrome ED presentations were five in 2015 (4.3%) and 12 in 2018(7.6%), although not statistically significant (P = .25).

CONCLUSIONS

Changes to food allergy prevention guidelines recommending the earlier introduction of allergenic food may have led to a small increase in ED presentations for food allergy but not anaphylaxis.

Diagnostic and Management Strategies of Food Protein-Induced Enterocolitis Syndrome: Current Perspectives

Food protein-induced enterocolitis syndrome (FPIES) is a form of non-IgE mediated food allergy that presents with delayed gastrointestinal symptoms after ingestion of the trigger food. The data regarding FPIES are sparse, despite being recognized as a distinct clinical entity. This narrative review presents the characteristics of this disorder in the pediatric population, as well-standard diagnostic and management protocols. FPIES can be classified into acute and chronic subtypes, and some cases may develop into an IgE-mediated allergy. Given that skin prick tests and specific IgE levels are negative in the majority of cases, diagnosis relies on clinical history and oral food challenges. Management involves elimination diets, assessment of tolerance through oral food challenges, and rehydration in the event of a reaction. Future research should focus on improving diagnostic methods, illustrating underlying pathogenesis and biomarkers, and assessing long-term natural history. Increased knowledge and awareness for FPIES are required.

Pearls and pitfalls in food protein-induced enterocolitis syndrome (FPIES)

Background: Food protein-induced enterocolitis syndrome (FPIES) is a rare, non-immunoglobulin E (IgE) mediated gastrointestinal food hypersensitivity. It is a clinical diagnosis commonly characterized by profuse vomiting 1 to 4 hours after ingestion of the triggering food(s). Objective: The objective was to increase awareness of FPIES and review the epidemiology, clinical presentation, pathogenesis, diagnosis, and management of FPIES. The lack of availability of a definite biomarker or diagnostic tool often leads to a delay in diagnosis. Methods: A literature search of salient articles that described case reports and case series of FPIES and their management were analyzed. Results: A case of FPIES with a literature review is presented with emphasis on clinical pearls and pitfalls. FPIES is a diagnosis of exclusion and the mainstay of treatment is avoidance of the trigger food(s) for at least 12-18 months from the last exposure. Conclusion: As FPIES is a non-IgE-mediated reaction, allergy testing via skin-prick test or blood tests to measure food IgE antibodies is not routinely recommended. Many children outgrow FPIES by 3-4 years of age. Supervised oral food challenge is recommended to assess acquisition of tolerance.

A case report of acute food protein-induced enterocolitis syndrome to walnut

BACKGROUND

Food protein-induced enterocolitis syndrome (FPIES) is a delayed, non-IgE-mediated food allergy. This syndrome was once thought to be rare, but emerging literature suggests an increasing incidence along with more foods being implicated. Also, with the introduction of guidelines on early peanut introduction, peanut-induced FPIES seems to be increasing in Australia and USA. Although most patients are diagnosed with FPIES within the first year of life, most commonly with food triggers to cow's milk or soy, other phenotypes exist in comparison to this classic presentation. In this case report, we present a patient with late onset of acute FPIES at age 3 to walnut.

CASE PRESENTATION

We describe a case of FPIES in a 12-year-old boy who had recurrent episodes of repetitive emesis, that began at age 3, each time after consuming walnuts. Mom does not give a history of intentional feeding (or avoidance) of walnut and/ or pecans. She also described possible reactions with pine nuts and macadamia. He was assessed with an oral food challenge to walnut, which triggered an episode of acute FPIES. He developed vomiting with onset 2 h post-ingestion, pallor, lethargy, and required an emergency department visit for anti-emetic medications and oral rehydration therapy. He improved on the therapy and now avoids cashew, pistachio, hazelnuts, walnuts, pecans, pine nuts, and macadamia nuts.

CONCLUSIONS

This case report adds to the limited literature that exists on culprit food allergens in FPIES. We present an acute FPIES triggered by the ingestion of walnuts. The diagnosis, common food triggers, and natural history of FPIES are described. There remains a lack of information on the natural history of FPIES, especially towards uncommon food triggers and on FPIES that present beyond infancy.

Early infancy dysbiosis in food protein-induced enterocolitis syndrome: A prospective cohort study

BACKGROUND

The microbiome associations of food protein-induced enterocolitis syndrome (FPIES) are understudied. We sought to prospectively define the clinical features of FPIES in a birth cohort, and investigate for the evidence of gut dysbiosis.

METHODS

We identified children diagnosed with FPIES in the Gastrointestinal Microbiome and Allergic Proctocolitis Study, a healthy infant cohort. Children were assessed and stools were collected at each well child visit. The clinical features of the children with FPIES were summarized. Stool microbiome was analyzed using 16S rRNA sequencing comparing children with and without FPIES.

RESULTS

Of the 874 children followed up for 3 years, 8 FPIES cases (4 male) were identified, yielding a cumulative incidence of 0.92%. The most common triggers were oat and rice (n = 3, each) followed by milk (n = 2). The children with FPIES were more likely to have family history of food allergy (50% vs. 15.9% among unaffected, p = .03). The average age of disease presentation was 6 months old. During the first 6 months of life, stool from children with FPIES contained significantly less Bifidobacterium adolescentis, but more pathobionts, including Bacteroides spp. (especially Bacteroides fragilis), Holdemania spp., Lachnobacterium spp., and Acinetobacter lwoffii. The short-chain fatty acid (SCFA)-producing Bifidobacterium shunt was expressed significantly less in the stool from FPIES children.

CONCLUSIONS

In this cohort, the cumulative incidence over the 3-year study period was 0.92%. During the first 6 months of life, children with FPIES had evidence of dysbiosis and SCFA production pathway was expressed less in their stool, which may play an important role in the pathogenesis of FPIES.

Perspectives on Non-IgE-Mediated Gastrointestinal Food Allergy in Pediatrics: A Review of Current Evidence and Guidelines

Food allergy is an immune-mediated disease that can result in considerable morbidity and even mortality, with a significant negative impact on patients' quality of life. It is characterized by allergic symptoms that can occur shortly after a relevant food allergen ingestion, or can be delayed or chronic, which make it more difficult for diagnosis. The symptoms of this disease can range from mild to severe, and rarely can cause anaphylaxis, a life-threatening allergic reaction. The prevalence of non-immunoglobulin E (IgE)-mediated food allergy is poorly established outside of cow's milk allergy, with an adjusted incidence ranging between 0.13% and 0.72%. Several disorders are classified as non-immunoglobulin E (IgE)-mediated food allergies that predominantly affect the gastrointestinal tract including food protein-induced enterocolitis syndrome (FPIES), food protein-induced allergic proctocolitis (FPIAP), food protein-induced allergic enteropathy (FPE), and food protein-induced dysmotility disorders (GORD and constipation). Eosinophilic esophagitis (EoE) is listed in this group, even though it considered by some authorities to be mixed reaction with both IgE and cell-mediated immune response to be involved in the reaction. The most common types of non-IgE-mediated food allergy are food protein-induced enterocolitis syndrome (FPIES) and food protein-induced allergic proctocolitis (FPIAP). These disorders typically present in infancy and are often triggered by cow's milk protein. Patients with FPIES present with profuse emesis and dehydration, while FPIAP patients present with hematochezia in otherwise healthy infants. Since there are no specific confirmatory non-invasive diagnostic laboratory tests, the diagnosis is usually made clinically when typical symptoms improve upon the removal of the culprit food. Food reintroduction should be attempted, when possible, with documentation of symptoms of relapse to confirm the diagnosis. The management includes dietary avoidance, supportive treatment in the case of accidental exposure, and nutritional counseling. This review focuses on the clinical manifestations, epidemiology, management, and recent guidelines of the most common non-IgE-mediated food hypersensitivity disorders (FPIES, FPIAP, and FPE).

Food protein-induced enterocolitis syndrome: Healthcare utilization and referral patterns among a pediatric cohort

Background

Food protein-induced enterocolitis syndrome (FPIES) is a non-IgE mediated food allergy characterized by delayed, repetitive vomiting. FPIES is improving in recognition; however, there remains a lag in diagnosis. This study aimed to further explore this lag, as well as referral patterns and healthcare utilization, to help determine areas for earlier recognition.

Methods

A retrospective chart review of pediatric FPIES patients at two hospital systems in New York was completed. Charts were reviewed for FPIES episodes and healthcare visits prior to diagnosis, and reason/source of referral to an allergist. A cohort of patients with IgE-mediated food allergy was reviewed for comparison of demographics and the time to the diagnosis.

Results

In total, 110 patients with FPIES were identified. The median time to diagnosis was 3 months, vs. 2 months in IgE-mediated food allergy (p < 0.05). Most referrals were from the pediatrician (68%) or gastroenterology (28%), none were from the ED. The most common reason for referral was concern of IgE-mediated allergy (51%), followed by FPIES (35%). There was a statistically significant difference in race/ethnicity between the FPIES cohort and IgE-mediated food allergy group (p < 0.0001), with a greater proportion of Caucasian patients in FPIES vs. IgE-mediated food allergy cohort.

Conclusion

This study demonstrates a lag in the diagnosis of FPIES and a lack of recognition outside of the allergy community, as only one-third of patients were considered to have FPIES prior to an allergy evaluation.

Food protein-induced enterocolitis syndrome with pneumatosis intestinalis in an exclusively breastfed infant: A case report and literature review

A 1-month-old male, exclusively breastfed, presented with 24 h of bloody stools, vomiting, metabolic acidosis, and pneumatosis intestinalis. The patient was initially treated for necrotizing enterocolitis (NEC). However, after suspecting food protein-induced enterocolitis syndrome (FPIES), oral feeding was resumed using an exclusive elemental formula, and the biochemical and radiological findings were resolved.

Recent Update in Food Protein-Induced Enterocolitis Syndrome: Pathophysiology, Diagnosis, and Management

Food protein-induced enterocolitis syndrome (FPIES), though first reported in the 1970s, remains poorly understood and likely underdiagnosed. It is a non-immunoglobulin E (IgE)-mediated food allergy syndrome, most commonly identified in infancy and childhood. It can manifest as a constellation of symptoms following food ingestion, including repetitive and projectile emesis (1-4 hours), accompanied by pallor, lethargy, muscular hypotonia, and diarrhea (5-10 hours). In more severe reactions, significant leukocytosis with neutrophilia, thrombocytosis, metabolic derangements, methemoglobinemia, anemia, low albumin, and total protein may be present. Hypotension and ultimately hypovolemic distributive shock may occur in up to 15%-20% of cases. The diagnosis of FPIES is challenging and providers continue to face difficulties in management. This review article aims to highlight the most recent updates in epidemiology, natural history, pathophysiology, potential diagnostic markers, and guidelines for the management of FPIES.

Intestinal microbiota is modified in pediatric food protein-induced enterocolitis syndrome

Background

Food protein-induced enterocolitis syndrome (FPIES) is a non-IgE-mediated food hypersensitivity that affects the gastrointestinal system, especially in children, who often present with more severe clinical manifestations than adults do. Although its pathogenesis is poorly understood and biomarkers are still lacking, scientific evidence suggests that gut microbiota may play an important role in the development of FPIES.

Objective

We aimed to compare the composition of gut microbiota in children with FPIES with that in age- and sex-matched healthy controls.

Methods

We analyzed the gut microbiota profiles in fecal samples of 17 patients with FPIES (case patients) and 12 age-matched healthy children (controls) by tag sequencing of the 16S ribosomal RNA gene hypervariable V4-V5 regions. Subjects' sociodemographic, clinical, and food diary variables were described and compared between groups by using inferential statistical tests. Nonparametric linear discriminant analysis was performed for intestinal microbiota data.

Results

Patients with confirmed cases FPIES (n = 17; average patient age, 7.5 ± 3.2 years) and controls without FPIES or any atopy (n = 12, average patient age, 6.9 ± 2.7 years) were included. Fish was the main FPIES-inducing allergen in 65% of the cases. The patients with FPIES showed higher proportions of Lachnospiraceae spp (P < .0286) and a lower proportion of Ruminococcaceae spp (P < .0066), Lactobacillaceae spp (P < .0075), and Leuconostocaceae spp (P < .0173) than the controls.

Conclusions

Our data clearly show a different gut microbial signature in patients with FPIES, suggesting a new potential avenue for aiding the diagnosis and clinical management of FPIES. Larger studies are needed to confirm these results.

The Role of the Gut Microbiome in Cow's Milk Allergy: A Clinical Approach

Cow's milk allergy (CMA) is the most prevalent food allergy (FA) in infancy and early childhood and can be present with various clinical phenotypes. The significant increase in FA rates recorded in recent decades has been associated with environmental and lifestyle changes that limit microbial exposure in early life and induce changes in gut microbiome composition. Gut microbiome is a diverse community of microbes that colonize the gastrointestinal tract (GIT) and perform beneficial functions for the host. This complex ecosystem interacts with the immune system and has a pivotal role in the development of oral tolerance to food antigens. Emerging evidence indicates that alterations of the gut microbiome (dysbiosis) in early life cause immune dysregulation and render the host susceptible to immune-mediated diseases later in life. Therefore, the colonization of the gut by "healthy" microbes that occurs in the first years of life determines the lifelong health of the host. Here, we present current data on the possible role of the gut microbiome in the development of CMA. Furthermore, we discuss how gut microbiome modification might be a potential strategy for CMA prevention and treatment.

Remission of Acute Food Protein-Induced Enterocolitis Syndrome Confirmed by Oral Food Challenges in Japan

The oral food challenge test (OFC) is the gold standard for evaluating the remission of food protein-induced enterocolitis syndrome (FPIES). Few acute FPIES remissions confirmed by OFC were reported. This study aimed to examine the OFC for Japanese children with acute FPIES to evaluate its remission. A retrospective cohort study was performed on children with acute FPIES with remission evaluation by OFC based on one food challenge dose (1/50, 1/10, 1/2, and full dose per day). Acute FPIES remission was observed in 65.2% of patients (15/23 patients). Vomiting episodes occurred with 1/50 full doses on the first day among 75% of positive patients. The median duration between the onset and OFC was 14 months (IQR, 8-24 months). Soy was the most common causative food, followed by egg yolk, milk, and wheat. All patients could receive OFC safely without intensive care unit care, based on the FPIES OFC protocol. The remission rate of acute FPIES was high. However, vomiting episodes commonly occurred with 1/50 full doses on the first day. This study suggested that our OFC protocol for acute FPIES was safe and feasible, but it might be safer for some patients to start at a minimal loading dose.

Predictors of initial oral food challenge outcome in food protein-induced enterocolitis syndrome

Background

There is a paucity of data on predictors of clinical history in oral food challenge (OFC) outcome for the initial diagnosis of food protein-induced enterocolitis syndrome (FPIES).

Objective

This study aimed to identify predictors for the diagnosis of FPIES.

Methods

The study included patients who underwent OFC to diagnose FPIES from 2010 to 2021. Patients with a positive OFC result were classified as belonging to the FPIES group, and those with negative OFC result within 120 days from the last symptomatic episode were classified as belonging to the no-allergy (NA) group. Background factors were analyzed in the groups.

Results

A total of 50 OFCs to 12 different foods were conducted in 50 patients. Of those 50 patients, 30 were classified as belonging to the FPIES group. No significant difference was observed between the FPIES and NA groups with respect to background factors, including the features of symptomatic episodes and examinations of immediate-type allergy. A history of asymptomatic ingestion was observed in 23 of 24 and 13 of 19 patients in the FPIES and NA groups, respectively; thus, it was significantly more common in patients with FPIES. The diagnostic rate of patients with fewer than 3 symptomatic episodes was 52%, and that of patients with 3 episodes or more was 75%, not considering a patient without available data.

Conclusions

A definite diagnosis of FPIES should be based on OFC, as there are no predictors for OFC positivity other than a history of asymptomatic ingestion. The absence of asymptomatic ingestion history was a negative predictor for the diagnosis of FPIES.

Cow's milk αS1-casein is more sensitizing than goat's milk αS1-casein in a mouse model

The aim of this study was to compare the sensitization of α_S1-CN in cow and goat's milk in a mouse model. Fifty mice were divided into control group, adjuvant control group, cow's milk α_S1-CN sensitized group, goat's milk α_S1-CN sensitized group and cross sensitized group. Cow's and goat's milk α_S1-CN were used to establish a mouse sensitization model. The results showed that cow's milk α_S1-CN had higher allergenicity than goat's milk α_S1-CN, as can be seen in significantly increased s-IgE and Th2 cell-related inflammatory factors, the proportion of Th2, and the expression of Th2 cell-related transcription factors. Furthermore, the sensitization of cow's milk α_S1-CN damaged the intestinal barrier of mice, caused the leakage of LPS, activated the TLR4-NFκB pathway, and thus resulted in the increase of IFN-γ. In addition, mice allergic to cow's milk α_S1-CN were less sensitized to goat's milk α_S1-CN.

Food protein-induced enterocolitis syndrome in a tertiary pediatric center: safety of guideline-conforming food challenges

Food protein-induced enterocolitis syndrome is a non-IgE-mediated reaction to food that is poorly understood, and underdiagnosed. Trigger foods can belong to any food group, but are most commonly milk, soy, rice, oat, egg, and fish. In this retrospective study (2015–2020), we describe the clinical presentations and triggers of 37 children referred to tertiary hospital with a confirmed or suspected diagnosis of food protein-inducted enterocolitis. We reviewed the safety of current recommendations by looking at the outcome of 24 oral food challenges. All of these patients presented with clear cut systemic reactions including lethargy. We also assessed the severity of the reactions. Oral food challenges occurred in the hospital day unit with the majority of patients having IV access in place. Despite a clear history of FPIES with lethargy and the requirement for re-hydration of the challenged population, 21/24 (88%) of the FPIES OFCs were successful. Of the three patients who reacted, symptoms were of moderate nature, mainly vomiting. This highlights the importance of early diagnosis and a pro-active approach to performing guideline-directed oral food challenges in patients with food protein-induced enterocolitis syndrome.

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.

Dietary exposures and allergy prevention in high-risk infants

Infants at high risk for developing a food allergy have either an atopic condition (such as eczema) themselves or an immediate family member with such a condition. Breastfeeding should be promoted and supported regardless of issues pertaining to food allergy prevention, but for infants whose mothers cannot or choose not to breastfeed, using a specific formula (i.e., hydrolyzed formula) is not recommended to prevent food allergies. When cow's milk protein formula has been introduced in an infant's diet, make sure that regular ingestion (as little as 10 mL daily) is maintained to prevent loss of tolerance. For high-risk infants, there is compelling evidence that introducing allergenic foods early-at around 6 months, but not before 4 months of age-can prevent common food allergies, and allergies to peanut and egg in particular. Once an allergenic food has been introduced, regular ingestion (e.g., a few times a week) is important to maintain tolerance. Common allergenic foods can be introduced without pausing for days between new foods, and the risk for a severe reaction at first exposure in infancy is extremely low. Pre-emptive in-office screening before introducing allergenic foods is not recommended. No recommendations can be made at this time about the role of maternal dietary modification during pregnancy or lactation, or about supplementing with vitamin D, omega 3, or pre- or probiotics as means to prevent food allergy.

Different Patterns of Foods Triggering FPIES in Germany

BACKGROUND

Food protein-induced enterocolitis syndrome (FPIES) is a non-IgE-mediated gastrointestinal food allergy mainly affecting infants and young children. Allergic FPIES reactions differ from IgE-mediated food allergies, for example, regarding elicitors and clinical course.

OBJECTIVE

The aim of our study was to describe causative agents and development of tolerance in German children with FPIES.

METHODS

We conducted a retrospective survey on children with FPIES from 14 centers in Germany assessing a 6-year period.

RESULTS

We analyzed 142 patients with 190 FPIES reactions, 130 of which met acute FPIES criteria and 60 were defined as chronic FPIES. The most frequent eliciting food for acute FPIES was cow's milk, followed by fish, vegetables (eg, potato, pumpkin), meats (eg, beef), and grains. A total of 119 children reacted to 1 food only, 16 children to 2 or 3 foods, and 7 children to ≥4 foods. In chronic FPIES, all but 4 exclusively breastfed infants reacted to cow's milk feeding. IgE sensitization to the triggering food was found in 21 of 152 (14%) cases. Two children developed additional IgE-mediated symptoms upon a food challenge. Time to proof of tolerance was shortest in cow's milk-induced FPIES, and it was shorter in chronic than in acute FPIES.

CONCLUSION

In our national survey, we identified triggers for acute FPIES that partially differ from those reported internationally. Mainly foods introduced early in infant nutrition triggered acute reactions. Time to proven tolerance was shown to be contingent on FPIES symptomatology and on the triggering food. These data should be considered regarding nutritional advice for infants with FPIES.

Food protein-induced enterocolitis syndrome: A large French multicentric experience

BACKGROUND

Food protein-induced enterocolitis syndrome (FPIES) is a non-IgE-mediated food allergy, with potential dehydration secondary to vomiting. Differences exist regarding culprit foods, and age of tolerance depending on the country of origin. We aimed at describing the characteristics of a French population of children with FPIES, and define risk factors for failure during challenge.

METHODS

Data from 179 children who were referred for FPIES in two pediatric tertiary centers between 2014 and 2020 were retrospectively collected. The diagnosis of FPIES was based on international consensus guidelines. Clinical characteristics, culprit food, and age at resolution were assessed. Tolerance was defined as no adverse reaction after OFC or accidental exposure.

RESULTS

In the 192 described FPIES, the age at first symptoms was 5.8 months old. The main offending foods were cow's milk (60.3%), hen's egg (16.2%), and fish (11.7%). Single FPIES was observed in 94.4% and multiple FPIES in 5.6% of cases. The age at resolution of FPIES was 2.2 years old, and resolution occurred later for fish than for milk (2.9 years vs. 2.0, p = 0.01). Severe acute FPIES was a risk factor for delayed resolution (RR: 3.3 [1.2-9.2]), but not IgE sensitization. Performing a food challenge within 12 months after the first reaction increased the risk of failure (OR: 2.6 [1.1-6.6]).

CONCLUSION

In this French cohort of children with FPIES, the main culprit foods were ubiquitous. Rice, oat, and soy were rarely or not involved. Multiple FPIES was infrequent. Our data confirmed the overall good prognosis of FPIES, the later resolution of FPIES to fish and in the case of severe acute FPIES.

Modified oral food challenge protocol approach in the diagnosis of Food Protein-Induced Enterocolitis Syndrome

Background

Food Protein-Induced Enterocolitis Syndrome (FPIES) is a non-IgE mediated food allergy most commonly presenting in infants. The most common food triggers include soy, cow’s milk and grains. Symptoms may include intractable vomiting, diarrhea, lethargy, pallor, abdominal distention, hypotension and/or shock. Oral food challenges (OFCs) given at food protein dose of 0.06–0.6 g/kg in 3 equivalent doses administered over a few hours are recommended in guidelines to confirm a diagnosis.

Case presentation

The patient is a 6-month-old girl with a history of severe FPIES symptoms to egg. In our clinic, we perform OFC with 1/100 serving dose on visit 1 and then increase the dose monthly. The patient takes the tolerated dose daily at home between visits. An OFC to baked egg at 1/100 of a serving was performed and was well-tolerated on her initial visit. The patient remained on the same dose upon returning home. Within 1-week, she developed FPIES symptoms including watery diarrhea and severe emesis requiring ondansetron. She required an Emergency Department visit for one of the reactions.

Conclusions

Our patient had severe FPIES symptoms with a small amount of egg. We believe that administration of three large food challenge doses on one clinic visit, as guidelines currently suggest, does not allow adequate time for symptoms to appear. Our patient likely would have suffered a severe reaction. Also, this guidelines protocol does not allow for monitoring of more delayed or chronic FPIES. We propose a modified protocol to OFCs with cautious up-dosing to allow for safer OFCs and monitoring of chronic FPIES. We have implemented an OFC approach where only one food challenge dose (starting with 1/100 of final dose) is given at each visit. The up-titration of the dose is completed every 4-weeks with one dose only. When the serving sized dose is reached and tolerated, the food can be maintained in the diet.

Food Protein-Induced Enterocolitis Syndrome in Children with Down Syndrome: A Pilot Case-Control Study

Food protein-induced enterocolitis syndrome (FPIES) is a non-immunoglobin E-mediated food hypersensitivity disorder. However, little is known about the clinical features of FPIES in patients with Down syndrome (DS). Medical records of children with DS diagnosed at our hospital between 2000 and 2019 were retrospectively reviewed. Among the 43 children with DS, five (11.6%) were diagnosed with FPIES; all cases were severe. In the FPIES group, the median age at onset and tolerance was 84 days and 37.5 months, respectively. Causative foods were cow’s milk formula and wheat. The surgical history of colostomy was significantly higher in the FPIES group than in the non-FPIES group. A colostomy was performed in two children in the FPIES group, both of whom had the most severe symptoms of FPIES, including severe dehydration and metabolic acidosis. The surgical history of colostomy and postoperative nutrition of formula milk feeding may have led to the onset of FPIES. Therefore, an amino acid-based formula should be considered for children who undergo gastrointestinal surgeries, especially colostomy in neonates or early infants. When an acute gastrointestinal disease is suspected in children with DS, FPIES should be considered. This may prevent unnecessary tests and invasive treatments.

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.

Histopathology of intestinal villi in neonatal and paediatric age: main features with clinical correlation - Part II

In this paper, we will continue the description of histological findings of infantile and paediatric small bowel alterations with the main clinical pictures and differential diagnosis. We emphasise once again the need to evaluate the biopsies in an adequate clinical contest and with a systematic approach, including epithelial alterations, lamina propria changes, mucosal architecture, and the distribution of inflammation, together with other morphological signs more specific of certain diseases. We describe the histological findings of coeliac and Crohn’s disease, gastrointestinal food allergic diseases, Langerhans cell histiocytosis, nutritional deficiencies and infections. Finally, we suggest the principal issues in the drafting the pathological report for appropriate interpretation and usefulness in clinical practice.

Chronic Milk-Dependent Food Protein-Induced Enterocolitis Syndrome in Children from West Pomerania Region

Characteristics of chronic milk-dependent food protein-induced enterocolitis syndrome (FPIES) in children from the region of Western Pomerania were studied. Prospectively, 55 children were diagnosed at a median of 2.2 months. The open food challenges (OFC), morphologies, milk-specific IgE (sIgE) (FEIA method, CAP system), and skin prick tests (SPTs) were examined. Vomiting and diarrhea escalated gradually but quickly led to growth retardation. Of the infants, 49% had BMI < 10 c, 20% BMI < 3 c; 25% had anemia, and 15% had hypoalbuminemia. During the OFCs we observed acute symptoms that appeared after 2-3 h: vomiting diarrhea and pallor. A total of 42% children required intravenous hydration. Casein hydrolysates or amino acids formulae (20%) were used in treatment. In 25% of children, SPT and milk sIgE were found, in 18%-other food SPTs, and in 14% allergy to other foods. A transition to IgE-dependent milk allergy was seen in 3 children. In the twelfth month of life, 62% of children had tolerance to milk, and in the twenty-fifth month-87%. Conclusions. Chronic milk-dependent FPIES resolves in most children. By the age of 2 children are at risk of multiple food sensitization, and those who have milk sIgE are at risk to transition to IgE-mediated milk allergy. Every OFC needs to be supervised due to possible severe reactions.

Non-IgE-Mediated Gastrointestinal Food Protein-Induced Allergic Disorders. Clinical Perspectives and Analytical Approaches

Non-IgE-mediated gastrointestinal food allergy (non-IgE-GI-FA) is the name given to a series of pathologies whose main entities are food protein-induced allergic proctocolitis (FPIAP), food protein-induced enteropathy (FPE), and food protein-induced enterocolitis syndrome (FPIES). These are more uncommon than IgE-mediated food allergies, their mechanisms remain largely unknown, and their diagnosis is mainly done by clinical history, due to the lack of specific biomarkers. In this review, we present the latest advances found in the literature about clinical aspects, the current diagnosis, and treatment options of non-IgE-GI-FAs. We discuss the use of animal models, the analysis of gut microbiota, omics techniques, and fecal proteins with a focus on understanding the pathophysiological mechanisms of these pathologies and obtaining possible diagnostic and/or prognostic biomarkers. Finally, we discuss the unmet needs that researchers should tackle to advance in the knowledge of these barely explored pathologies.

Differentiation of food protein-induced enterocolitis syndrome misleading to necrotizing enterocolitis

BACKGROUND

Food protein-induced enterocolitis syndrome (FPIES) is a rare non-immunoglobulin E-mediated food allergy with necrotizing enterocolitis (NEC)-like symptoms which requires differential diagnosis as treatments differ.

OBJECTIVE

To evaluate the clinical, laboratory, and radiologic findings that differentiate FPIES from NEC in preterm and term infants.

METHODS

Clinical features, comorbidities, and laboratory and radiologic findings of neonates with presumed NEC were reviewed retrospectively and compared between FPIES and NEC in preterm and term infants who were admitted to the neonatal intensive care unit at Seoul National University Bundang Hospital between May 2003 and February 2020.

RESULTS

A total of 10 of 150 (6.7%) preterm and 17 of 38 (44.7%) term infants with presumed NEC were confirmed to have FPIES; the remainder had NEC by modified Bell's criteria. Demographics and comorbidities were similar between these groups. Symptoms such as hematochezia, shock, leukocytosis, peripheral eosinophilia, and feeding of extensively hydrolyzed milk formula or elemental formula after discharge were significantly different between the 2 groups in term infants (P <.05), but not in preterm infants. On abdominal ultrasonography, pneumatosis intestinalis was more common among preterm FPIES (44.4%) than NEC cases (21.6%) (P =.04). Among the preterm infants, 4 FPIES (40%) and 25 NEC (17.9%) cases required surgery (P =.10).

CONCLUSION

Differentiating FPIES in neonates suspected of having NEC is important as dietary elimination of the triggering milk protein can be recommended instead of prolonged fasting and antibiotic treatment, which are indicated for NEC, in both term and preterm infants.

Oral Food Challenge for FPIES in Practice-A Survey: Report from the Work Group on FPIES Within the Adverse Reactions to Foods Committee, FAED IS, AAAAI

BACKGROUND

Food protein-induced enterocolitis syndrome (FPIES) is a non-IgE-mediated food allergy diagnosed via history and/or an oral food challenge (OFC).

OBJECTIVE

To determine allergists' approach to FPIES OFCs.

METHODS

A web-based survey was e-mailed to 1100 randomly selected American Academy of Allergy, Asthma and Immunology members.

RESULTS

A total of 132 individuals responded (12% response rate). A total of 95.5% (n = 105) of respondents perform OFCs in their practice, but only 58.7% (n = 71) perform FPIES OFCs. The median number of FPIES OFCs in children was reported as 3 per year (range, 0-76); all but 1 respondent (2.5%) had not performed any FPIES OFCs in adults. The most common FPIES OFC foods were cow's milk, rice, lightly cooked egg, oat, soy, baked milk, and baked egg. The decision to offer FPIES OFCs was based on the severity of past reactions, the patient and family's desire, and the patient's age. FPIES OFCs were most commonly performed in an outpatient setting, with placement of peripheral intravenous access depending on the severity of past reactions and with a serving appropriate for age divided into 3 equal portions administered over 30 minutes. There was significant variability in the approach to conducting FPIES OFCs. Most respondents (87.4%, n = 127) indicated that specific guidelines for performing FPIES OFCs would be helpful.

CONCLUSIONS

Our study highlights the discordance in allergists' practices performing OFCs for IgE-mediated food allergy compared with FPIES. The lack of universal agreement on the optimal way to perform OFCs in FPIES demonstrates the need for future studies to develop a standardized protocol for FPIES OFCs.

Drug-induced enterocolitis syndrome: Similarities and differences compared with food protein-induced enterocolitis syndrome

In 2014, drug-induced enterocolitis syndrome (DIES) was described for the first time. It is still a poorly known disease with symptoms that typically resemble those of food protein-induced enterocolitis syndrome (FPIES). To date, six more cases of DIES have been described and new clinical diagnostic criteria have been proposed based on those in the international guidelines for FPIES. In this paper, the authors describe three more cases of DIES. In addition, similarities and differences with FPIES have been deeply analyzed. To date, several unanswered questions need to be addressed, but clinicians must be instructed how to identify DIES, in order to make an allergy workup and give definite therapeutic indications to patients, especially in children where DIES seems to be more frequent.