Food Protein-Induced Enterocolitis Syndrome in Adulthood: Clinical Characteristics, Prognosis, and Risk Factors

Adults with FPIES may face delayed diagnoses

Background

Food protein-induced enterocolitis (FPIES) is a non-IgE-mediated food allergy that is becoming increasingly recognized in adults. The time between age at symptom onset (ASO) and age at diagnosis (AD and factors affecting this gap have not been fully studied.

Objective

We sought to investigate the latency between ASO and AD in adults with FPIES. We also sought to evaluate whether those patients with symptom onset in earlier years and those with comorbid gastrointestinal (GI) disease had greater mean latency.

Methods

We conducted a retrospective chart review for patients with FPIES who were seen in the University of Michigan Allergy and Immunology clinic from 2015 to 2022. Patients aged 18 years and older and diagnosed with FPIES by an allergist were included (N = 19). The data collected included characteristics of the patients' prior FPIES reactions and medical history.

Results

The median age of onset of FPIES symptoms was 26 years, and the median AD was 35 years. The median difference between ASO and AD was 10 years; this difference was statistically significant according to a paired t test (P = .003). There was a negative correlation of -0.99 between year of symptom onset and latency between ASO and AD (P < .0001). Those patients with previously diagnosed GI conditions had a higher mean latency between ASO and AD than those without GI conditions did (P = .124).

Conclusions

We noted a gap between ASO and AD in adults with FPIES. This gap may be due to underrecognition of adult FPIES in the past given the negative correlation with mean latency between ASO and AD. Furthermore, comorbid GI illnesses may be masking FPIES symptoms in adults, thus delaying diagnosis.

Whole Exome Sequencing Identifies Epithelial and Immune Dysfunction-Related Biomarkers in Food Protein-Induced Enterocolitis Syndrome

BACKGROUND

Food protein-induced enterocolitis syndrome (FPIES) is a food allergy primarily affecting infants, often leading to vomiting and shock. Due to its poorly understood pathophysiology and lack of specific biomarkers, diagnosis is frequently delayed. Understanding FPIES genetics can shed light on disease susceptibility and pathophysiology-key to developing diagnostic, prognostic, preventive and therapeutic strategies. Using a well-characterised cohort of patients we explored the potential genome-wide susceptibility factors underlying FPIES.

METHODS

Blood samples from 41 patients with oral food challenge-proven FPIES were collected for a comprehensive whole exome sequencing association study.

RESULTS

Notable genetic variants, including rs872786 (RBM8A), rs2241880 (ATG16L1) and rs2289477 (ATG16L1), were identified as significant findings in FPIES. A weighted SKAT model identified six other associated genes including DGKZ and SIRPA. DGKZ induces TGF-β signalling, crucial for epithelial barrier integrity and IgA production; RBM8A is associated with thrombocytopenia absent radius syndrome, frequently associated with cow's milk allergy; SIRPA is associated with increased neutrophils/monocytes in inflamed tissues as often observed in FPIES; ATG16L1 is associated with inflammatory bowel disease. Coexpression correlation analysis revealed a functional correlation between RBM8A and filaggrin gene (FLG) in stomach and intestine tissue, with filaggrin being a known key pathogenic and risk factor for IgE-mediated food allergy. A transcriptome-wide association study suggested genetic variability in patients impacted gene expression of RBM8A (stomach and pancreas) and ATG16L1 (transverse colon).

CONCLUSIONS

This study represents the first case-control exome association study of FPIES patients and marks a crucial step towards unravelling genetic susceptibility factors underpinning the syndrome. Our findings highlight potential factors and pathways contributing to FPIES, including epithelial barrier dysfunction and immune dysregulation. While these results are novel, they are preliminary and need further validation in a second cohort of patients.

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.

Differences in Characteristics Between Patients Who Met or Partly Met the Diagnostic Criteria for Food Protein-Induced Enterocolitis Syndrome (FPIES)

BACKGROUND

Some patients with food protein-induced enterocolitis (FPIES)-like allergy do not completely fulfill the diagnostic criteria of the international consensus guideline for FPIES. However, it is unclear whether such FPIES-like patients represent a completely different population from FPIES.

OBJECTIVE

This study aimed to clarify differences in characteristics between patients with FPIES who fully met diagnostic criteria and those who partly met them.

METHODS

This was a cross-sectional study using data at the time of registration in multicenter, prospective studies of patients with FPIES in Japan. Children who had delayed emesis within 1 to 4 hours and/or diarrhea within 5 to 10 hours after ingestion of food were recruited between March 2020 and February 2022. We examined their compatibility with the diagnostic criteria of the international consensus guideline and their detailed clinical characteristics, including trigger foods, the serving size that elicited symptoms, and antigen-specific IgE antibody titers.

RESULTS

Of the 225 patients with FPIES, 140 fully met the diagnostic criteria whereas 79 patients did not fully meet them but demonstrated reproducible symptoms. The frequencies of pallor, lethargy, and diarrhea were significantly higher in those who met the criteria fully, whereas the age at onset, trigger foods, comorbidity, and perinatal information were comparable. Analysis of patients with FPIES to hen's egg revealed significantly higher levels of egg white- and egg yolk-specific IgE in patients who partly met criteria, whereas the serving size eliciting symptoms was comparable.

CONCLUSIONS

Patients who partly met the diagnostic criteria may have a milder phenotype of FPIES, but this needs to be validated in further studies using biomarkers reflecting the pathophysiology.

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.

A detailed intake-status profiling of seafoods in adult food-protein-induced enterocolitis syndrome patients

BACKGROUND

Adults with food-protein-induced enterocolitis syndrome (FPIES) often develop severe abdominal symptoms after eating seafood. However, no investigation of a food elimination strategy for adult FPIES patients has been performed to date.

METHODS

We conducted a retrospective cohort study of seafood-avoidant adults by telephone interview, based on the diagnostic criteria for adult FPIES reported by González et al. We compared the clinical profiles, abdominal symptoms, and causative seafoods between FPIES and immediate-type food allergy (IgE-mediated FA) patients. We also profiled the detailed intake-status of seafoods in adult FPIES patients.

RESULTS

Twenty-two (18.8 %) of 117 adults with seafood-allergy were diagnosed with FPIES. Compared with the IgE-mediated FA patients, FPIES patients had an older age of onset, more pre-existing gastrointestinal and atopic diseases, more episodes, longer latency and duration of symptoms, more nausea, abdominal distention, and severe abdominal pain, and more frequent vomiting and diarrhea. In particular, abdominal distention-reflecting intestinal edema and luminal fluid retention-may be the most distinctive characteristic symptom in adult FPIES (p < 0.001). Bivalves, especially oysters, were the most common cause of FPIES. Strikingly, intake-status profiling revealed that many FPIES patients can safely ingest an average of 92.6 % of seafood species other than the causative species.

CONCLUSIONS

There are many differentiators between FPIES and IgE-mediated FA, which may reflect differences in the underlying immunological mechanisms. Although seafood FPIES is unlikely to induce tolerance, many patients can ingest a wide variety of seafood species after a long period from onset.

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.

Personalization of Complementary Feeding in Children With Acute Food Protein-Induced Enterocolitis Syndrome

Food protein-induced enterocolitis syndrome (FPIES) is a food allergy that results in repetitive vomiting, lethargy, and pallor within 1 to 4 hours of food ingestion. One of the issues in its management is the introduction of new foods. Over the past 25 years, suggestions have been made mainly based on the likelihood that a given food family could induce an episode of acute FPIES. Thus, foods have been categorized into low, moderate, and high risk. The suggestion was always to postpone the introduction of moderate- or high-risk foods, leaving the decision whether to introduce them at home or in hospital to the doctor. These suggestions were designed for all children with acute FPIES, regardless of their geographical area. However, it is true that these suggestions are the result of expert opinion. In recent years, studies have been published that have shown that the risk category of foods varies according to geographical area and so does the prevalence of single FPIES versus multiple FPIES. For this reason, we believe that the introduction of new foods in the child with acute FPIES can and should be tailored according to the geographical area.

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.

Comparison of adult food protein-induced enterocolitis syndrome to crustaceans and immediate-type food allergy

BACKGROUND

Food protein-induced enterocolitis syndrome (FPIES) is increasingly found in adults. FPIES requires different treatment from immediate-type food allergy (FA) in emergency medicine. However, no comparison of the clinical presentations of these diseases has been reported.

OBJECTIVE

To compare the clinical presentations and causative crustaceans of adult FPIES and FA using a standardized questionnaire and to thereby lay the groundwork for establishing an algorithm that distinguishes those diseases.

METHODS

We conducted a retrospective cohort study of crustacean-avoidant adults by telephone interview based on the previously reported diagnostic criteria for adult FPIES to compare the clinical features and crustacean intake status between FPIES and FA.

RESULTS

Of 73 adult patients with crustacean allergy, 8 (11%) were diagnosed with having FPIES and 53 (73%) FA. Compared with the patients with FA, those with FPIES had a longer latency period (P < .01), more episodes (P = .02), longer duration of symptoms (P = .04), more frequent abdominal distention (P = .02), and severe colic pain (P = .02). Half of the patients with FPIES experienced fear of death during an episode. Panulirus japonicus (Japanese spiny lobster) and Homarus weber (lobster) were significantly common FPIES-causing foods. A statistically significant 62.5% of patients with FPIES were able to ingest some type of crustacean.

CONCLUSION

FPIES and FA can be clearly differentiated by the abdominal symptoms, latency period, and duration of episodes. Furthermore, some patients with FPIES do not necessarily need to avoid all crustaceans. Our findings lay the groundwork for establishing an algorithm that distinguishes FPIES from FA in adults.

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.

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).

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.