Four distinct subtypes of non–IgE-mediated gastrointestinal food allergies in neonates and infants, distinguished by their initial symptoms

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 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.

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.

Complementary food introduction practices in infants with intestinal failure

BACKGROUND

Oral intake in infants with intestinal failure (IF) may be limited due to intolerance or feeding difficulties. Guidelines for the introduction of semisolid or solid complementary foods (CFs) to infants with IF do not exist. CF intake and caloric contribution from CF is difficult to assess due to malabsorption and incomplete recording. The aim of this study was to identify institutional approaches to introducing CF to infants with IF.

METHODS

The American Society for Parenteral and Enteral Nutriton (ASPEN) Pediatric Intestinal Failure Section Registered Dietitian/Nutritionist (RDN) working group designed a 10-question online cloud-based survey to assess group member practice related to the introduction of CF to infants with IF.

RESULTS

Twenty-six surveys were completed. Thirteen (50%) RDNs recommend introduction of CF between 4 and 6 months of age. Nineteen (76%) recommend adding pureed foods to gastrostomy tube feedings. Seventeen (65%) follow standard infant feeding practice guidelines with half citing the American Academy of Pediatrics. Approximately half (44%) recommend introducing vegetables first and the majority (80%) recommend delaying the introduction of fruits. The vast majority (92%) recommend specific foods to minimize stool output including green beans, bananas, infant cereals, and meats/protein.

CONCLUSION

Institutional practices related to the introduction of CF to infants with IF vary. Similarities with first food choice and foods to avoid were observed. Evidenced-based practice guidelines for the introduction of CF to infants with IF need to be established to determine best practices for reducing stool output, encouraging weaning from parenteral nutrition, and achieving enteral autonomy.

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 use of amino acid formulas in pediatric patients with allergy to cow's milk proteins: Recommendations from a group of experts

One of the most common food allergies in children is cow's milk allergy (CMA). In breast-fed infants with CMA, the mother is encouraged to avoid dairy products. If this is not possible, or in formula fed infants, use of hypoallergenic replacement formulas such as extensively hydrolyzed formulas (EHF) is recommended. However, in ∼5% of patients EHFs are not tolerated and/or allergy symptoms can persist. When EHFs are ineffective and in severe forms of CMA, amino acid-based formulas (AAF) should be considered. Six pediatric gastroenterologists with extensive experience in food allergy management reviewed scientific publications and international clinical practice guidelines to provide practical recommendations on AAF. The guidelines reviewed had discrepancies and ambiguities around the specific indications for using formulas as a milk substitute. The panel recommends AAFs as the first therapeutic option in anaphylaxis due to CMA, in acute and chronic severe food protein-induced enterocolitis syndrome, in CMA associated with multiple food allergy, and in cases of eosinophilic esophagitis not responding to an extended exclusion diet or not eating solids. The main benefit of AAF is its absence of residual allergenicity, making it a safe treatment option in severe CMA patients who do not tolerate or respond to an EHF.

Malabsorption Syndromes and Food Intolerance

Feeding intolerance is ubiquitous in neonatal intensive care units with as many signs and symptoms as possible diagnoses. Optimizing nutrition is paramount in both preterm and term infants. Determining the cause of feeding intolerance and adjusting nutrition interventions is an important part of the daily care of newborns. This review discusses the role of malabsorption and food intolerance as possible causes of nutrition difficulties in the newborn.

Adult Food Protein-Induced Enterocolitis Syndrome

Food protein-induced enterocolitis syndrome (FPIES) is a non-IgE, cell-mediated food allergy, commonly diagnosed in infants and young children. In recent years, new-onset adult FPIES has been recognized. The underlying pathogenic mechanism of FPIES has yet to be elucidated, thus disease-specific diagnostic biomarkers have yet to be determined and an oral food challenge (OFC) remains the gold-standard for the diagnosis. Pediatric patients with FPIES classically present with symptoms of delayed, repetitive vomiting approximately 1 to 4 hours following ingestion of a food allergen. However, adults with FPIES have been reported to have a different symptom profile and different food triggers compared to the pediatric FPIES population. The current FPIES diagnostic criteria may not be appropriate for the diagnosis of adult FPIES patients, thus an oral food challenge remains a diagnostic tool. This review provides an overview of the current literature on the clinical presentation, epidemiology, diagnosis, triggers and management of adult FPIES.

Update on Food Protein-Induced Enterocolitis Syndrome (FPIES)

PURPOSE OF REVIEW

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

RECENT FINDINGS

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

Pathophysiology of Non-IgE-Mediated Food Allergy

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

Clinical features of pediatric eosinophilic gastroenteritis

BACKGROUND

No study has analyzed more than100 cases of eosinophilic gastroenteritis (EGE) in children in a single center. We aimed to describe the clinical features of pediatric EGE.

METHODS

This retrospective study was conducted at a single center. Between April 2007 and December 2017, 860 children between the ages of 1 year and 15 years underwent endoscopy for gastrointestinal symptoms of unknown cause. Among them, 109 (12.7%) were diagnosed with EGE according to the diagnostic criteria for EGE developed by the research group of the Ministry of Health, Labour and Welfare of Japan for eosinophilic gastrointestinal disorder in 2015. We investigated their symptoms, comorbidities, endoscopic findings, pathological findings, treatments, and outcomes.

RESULTS

Seventy-one boys (65.1%) and 38 girls (34.9%) were diagnosed with EGE. The median age at diagnosis was 11 years (range, 1-15 years). The chief complaints were abdominal pain in 83 (76.1%) and diarrhea in 26 (23.9%). Upper and lower gastrointestinal endoscopies showed normal findings in 32 patients (29.4%). The most common treatment was a combination of elimination of foods suspected of causing EGE and anti-allergic agents in 50 cases (45.9%). The outcomes were symptom disappearance in 43 patients (39.4%) and symptom improvement in 53 patients (48.6%).

CONCLUSIONS

For gastrointestinal symptoms of unknown cause in children, EGE should be considered as a differential diagnosis. Although the symptoms and endoscopic findings are nonspecific, cracked mucosa may be a specific endoscopic finding for pediatric EGE. An elimination diet and/or anti-allergic drugs were effective in most patients with pediatric EGE.

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.

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.

Clinical Manifestations of Pediatric Food Allergy: a Contemporary Review

Food allergies (FAs) are an emerging health care issue, and a "second wave of the allergy epidemic" was named. There are extensive data that documented the prevalence rate as high as approximately 10%. FAs are immunological adverse reactions, including IgE-mediated mechanisms, cell-mediated mechanisms, or mixed IgE- and cell-mediated mechanisms. A diagnosis of FA is made by specific symptoms encounter with food, detailed past history, sensitization tests, and oral food challenges (OFCs) if necessary. The component-resolved diagnostics (CRD) test can distinguish true or cross-reaction. "Minimal elimination" from the results of CRD and OFC could avoid unnecessary food restriction. Strict food limitation is harsh and stressful on patients and their families. Children with FAs experience a higher rate of post-traumatic stress symptoms (PTSS) and bullying than others. In the last 20 years, oral immunotherapy (OIT), sublingual immunotherapy (SLIT), and epicutaneous immunotherapy (EPIT) are treatment strategies. OIT and EPIT are the most two encouraging treatments for FA. This review aims to introduce FAs in diverse clinical disorders, new perspectives, and their practical implications in diagnosing and treating FA.

Food protein-induced enterocolitis syndrome: epidemiology and comorbidities

PURPOSE OF REVIEW

First described in the mid 20th century, it was just in the last decade that diagnostic and treatment guidelines for food protein-induced enterocolitis syndrome (FPIES) were established. Awareness of the diagnosis is improving, and epidemiologic data are emerging.

RECENT FINDINGS

Recent studies suggest that FPIES may affect as many as 0.5% of children worldwide. FPIES in adults is usually triggered by seafood and may be more common than previously thought. Many patients with FPIES have other allergic disorders.

SUMMARY

With refined diagnostic criteria and improved awareness, FPIES is now diagnosed with increasing frequency, and epidemiologic data are emerging. FPIES appears to be increasing in prevalence, and the frequent association with other allergic disorders suggests a shared predisposition or immune mechanism that remains to be elucidated.

Food Protein-Induced Enterocolitis Syndrome

Food protein-induced enterocolitis syndrome (FPIES) is a non-IgE-mediated food allergy that manifests with projectile, repetitive emesis that can be followed by diarrhea and may be accompanied by lethargy, hypotonia, hypothermia, hypotension, and metabolic derangements. FPIES usually starts in infancy although onset at older ages is being increasingly recognized. FPIES is not rare, with the cumulative incidence of FPIES in infants estimated to be 0.015% to 0.7%, whereas the population prevalence in the US infants was 0.51%. FPIES diagnosis is challenging and might be missed because of later (1-4 hours) onset of symptoms after food ingestion, lack of typical allergic skin and respiratory symptoms, and food triggers that are perceived to be hypoallergenic. Diagnosis is based on the recognition of symptoms because there are no biomarkers of FPIES. The pathophysiology remains obscure although activation of the innate immune compartment has been detected. Management relies of avoidance of food triggers, treatment of accidental exposures, and periodic re-evaluations with supervised oral food challenges to monitor for resolution. There are no strategies to accelerate development of tolerance in FPIES. Here we review the most important current concepts in epidemiology, pathophysiology, diagnosis, and management of FPIES.

The practical dietary management of food protein-induced enterocolitis syndrome

OBJECTIVE

Food protein-induced enterocolitis syndrome (FPIES) is a non-immunoglobulin E-mediated food allergy with potential risk of malnutrition related to the early onset of disease, frequent avoidance of cow's milk, and the possibility of multiple food triggers. This publication is aimed at providing an evidence-based, practical approach to the dietary management of FPIES.

DATA SOURCES

This is a narrative review summarizing information from national and international guidelines, retrospective studies, population studies, review articles, case reports, and case series to evaluate for nutritional risk and develop guidance for risk reduction in children with FPIES.

STUDY SELECTIONS

We have included retrospective clinical cohort studies, population-based studies, case reports, and case studies. We did not exclude any studies identified owing to the small number of studies addressing the nutritional management of individuals with FPIES.

RESULTS

Children with FPIES are at risk of malnutrition owing to suboptimal oral intake, limited food choices, and knowledge deficits related to feeding. In particular, children with 3 or more FPIES triggers seem to be at increased risk for poor weight gain and developing food aversion. Caregivers of children with FPIES also report a high degree of psychosocial burden.

CONCLUSION

Appropriate dietary management entails the following 3 essential components: supporting normal growth and development, avoidance of allergens, and advancement of complementary foods. Education to avoid the trigger food and assisting caregivers in creating an individualized, well-designed complementary feeding plan to meet the infant's nutritional needs for optimal growth and development are essential management strategies.

Food protein-induced enterocolitis syndrome epidemiology

OBJECTIVE

Food protein-induced enterocolitis syndrome (FPIES) is a condition with heterogeneous features (ie, age at presentation, severity, food triggers, comorbidities) and is not as rare as initially believed. In the last few years, the first population-based epidemiologic study, few prospective birth cohort evaluating FPIES prevalence, and several larger (>100 patients) studies have been published, making epidemiologic estimation more reliable. In this review, we report on the available data on the epidemiology of FPIES.

DATA SOURCES

PubMed review using the following words: FPIES, epidemiology, and prevalence.

STUDY SELECTIONS

The review focused on the population-based epidemiologic study, few prospective birth cohort evaluating FPIES prevalence, and several larger (>100 patients) studies.

RESULTS

We identified 8 population or cohort studies.

CONCLUSION

FPIES is not rare in both children and adults and may affect as many as 900,000 people in the United States alone. Most children and adult with FPIES seem to react to 1 to 2 foods; however, they may need further diet restriction owing to high level of comorbidity with immunoglobulin E-mediated food allergies and eosinophilic esophagitis. Globally, cow's milk, rice/oat, and seafood seem to be the most common triggers.

Obstructive Fecalomas in an Infant Treated with Successful Endoscopic Disimpaction

A fecaloma is a mass of accumulated feces with a consistency much harder than that of a fecal impaction. It is most frequently observed in the rectum and sigmoid area, and associated complications include colonic obstruction, ulceration, bleeding, and perforation. A one-year-old, previously healthy boy with no history of chronic constipation was admitted because of vomiting and abdominal distension. An abdominal computed tomography scan showed small and large bowel distension due to multiple obstructive fecalomas in the transverse colon. As the fecalomas could not be resolved by laxatives, enemas, or colonic lavage, endoscopic disimpaction under general anesthesia was attempted. Repeatedly shaving the fecalomas with biopsy forceps finally resulted in gradual fragmentation with subsequent passage. Gastrointestinal food allergy was later suggested as the cause because eosinophilic infiltration was found in a biopsy specimen of the colon wall. Endoscopic disimpaction is an effective treatment approach for addressing fecalomas to avoid more invasive surgical intervention.

Food protein-induced allergic proctocolitis may have distinct phenotypes

BACKGROUND

Food protein-induced allergic proctocolitis (FPIAP) is a non-immunoglobulin E (IgE)-mediated food allergy, which presents with bloody mucoid stool in infants. Although IgE-mediated allergy and sensitizations to offending foods have been described in other non-IgE-mediated food allergies, it has not been investigated in FPIAP.

OBJECTIVE

To investigate IgE-mediated allergy and sensitization to offending foods in FPIAP.

METHODS

Patients (n = 204) were retrospectively recruited and grouped as FPIAP (n = 180; FPIAP with or without the symptoms of IgE-mediated food hypersensitivity to offending and nonoffending foods at initial consultation), FPIAP-IgE sensitization to offending foods (n = 17), and FPIAP-transition to IgE-mediated allergy to offending foods (n = 7). The study was performed in accordance with the protocol approved by the local ethical committee of the Hacettepe University.

RESULTS

The median age of onset of symptoms and the development of tolerance was 2 months (interquartile range [IQR], 1.0-3.0) and 12 months (IQR, 10.0-14.0), respectively, and of the patients with skin prick test or serum specific IgE tests (n = 196), 38 (19.4%) had evidence of IgE sensitization to offending foods at the initial consultation or during follow-up; 17 (8.6%) had IgE sensitization, 7 (3.6%) indicated a transition to IgE-mediated allergy to FPIAP-induced foods. The median age of tolerance development of the FPIAP-transition group (19 months, IQR, 18.0-29.0) was significantly later than that of the FPIAP group (11 months, IQR, 10.0-14.0; P < .001) and the FPIAP-IgE sensitization group (11.0 months, IQR, 9.5-12.0; P < .001). Tolerance was observed within the study period in almost all the patients.

CONCLUSION

Children with FPIAP may have sensitization or develop IgE-mediated allergy over time to offending foods. In addition, IgE sensitization in FPIAP does not have an unfavorable effect on tolerance development; however, the transition to an IgE-mediated phenotype may delay tolerance for a brief time.

Non-IgE-Mediated Gastrointestinal Food Allergies in Children: An Update

Non-immunoglobulin E-mediated gastrointestinal food allergic disorders (non-IgE-GI-FA) include food protein-induced enterocolitis syndrome (FPIES), food protein-induced enteropathy (FPE) and food protein-induced allergic proctocolitis (FPIAP), which present with symptoms of variable severity, affecting the gastrointestinal tract in response to specific dietary antigens. The diagnosis of non-IgE-GI-FA is made clinically, and relies on a constellation of typical symptoms that improve upon removal of the culprit food. When possible, food reintroduction should be attempted, with the documentation of symptoms relapse to establish a conclusive diagnosis. Management includes dietary avoidance, nutritional counselling, and supportive measures in the case of accidental exposure. The prognosis is generally favorable, with the majority of cases resolved before school age. Serial follow-up to establish whether the acquisition of tolerance has occurred is therefore essential in order to avoid unnecessary food restriction and potential consequent nutritional deficiencies. The purpose of this review is to delineate the distinctive clinical features of non-IgE-mediated food allergies presenting with gastrointestinal symptomatology, to summarize our current understanding of the pathogenesis driving these diseases, to discuss recent findings, and to address currents gaps in the knowledge, to guide future management opportunities.

Japanese guidelines for food allergy 2020

Five years have passed since the Japanese Pediatric Guideline for Food Allergy (JPGFA) was first revised in 2011 from its original version. As many scientific papers related to food allergy have been published during the last 5 years, the second major revision of the JPGFA was carried out in 2016. In this guideline, food allergies are generally classified into four clinical types: (1) neonatal and infantile gastrointestinal allergy, (2) infantile atopic dermatitis associated with food allergy, (3) immediate-type of food allergy (urticaria, anaphylaxis, etc.), and (4) special forms of immediate-type of food allergy such as food-dependent exercise-induced anaphylaxis and oral allergy syndrome (OAS). Much of this guideline covers the immediate-type of food allergy that is seen during childhood to adolescence. Infantile atopic dermatitis associated with food allergy type is especially important as the onset of most food allergies occurs during infancy. We have discussed the neonatal and infantile gastrointestinal allergy and special forms of immediate type food allergy types separately. Diagnostic procedures are highlighted, such as probability curves and component-resolved diagnosis, including the recent advancement utilizing antigen-specific IgE. The oral food challenge using a stepwise approach is recommended to avoid complete elimination of causative foods. Although oral immunotherapy (OIT) has not been approved as a routine treatment by nationwide insurance, we included a chapter for OIT, focusing on efficacy and problems. Prevention of food allergy is currently the focus of interest, and many changes were made based on recent evidence. Finally, the contraindication between adrenaline and antipsychotic drugs in Japan was discussed among related medical societies, and we reached an agreement that the use of adrenaline can be allowed based on the physician's discretion. In conclusion, this guideline encourages physicians to follow the principle to let patients consume causative foods in any way and as early as possible.

Retrospective study identified fish and milk as the main culprits in cases of food protein-induced enterocolitis syndrome

AIM

Food protein-induced enterocolitis syndrome (FPIES) is a non-immunoglobulin E (IgE)-mediated food allergy, which is confined to the gastrointestinal tract and occurs most frequently in the first year of life. Our aim was to examine the clinical features, causative agents and outcomes of Greek children with FPIES.

METHODS

This was a five-year (2013-2017) retrospective study, based on chart reviews of 78 children with FPIES from six Greek paediatric allergy centres.

RESULTS

Only five children needed an oral food challenge (OFC) for diagnosis, but 54 children (69%) had OFCs to monitor tolerance development. The most common problems were fish and milk, which affected affecting 42 (54%) and 25 (35%) of children, respectively. The median age of tolerance based on the results of the negative OFCs occurred by 34.0 (26.6-58.4) months. Fish and milk were tolerated by 24 (57%) and 13 (52%) of children by 43.8 and 24.3 months, respectively. Coexisting IgE sensitisation to the offending food was related to delayed tolerance.

CONCLUSION

Fish and milk were the most common food allergies in our series of Greek children with FPIES. Cases with IgE sensitisation to the food trigger took longer to resolve their allergies.

Ultrasonographic study of intestinal Doppler blood flow in infantile non-IgE-mediated gastrointestinal food allergy

BACKGROUND

Although non-IgE-mediated gastrointestinal food allergy has increased rapidly in Japan, a small number of reports has evaluated B-mode and Doppler ultrasonographic findings in the acute phase of infantile gastrointestinal milk allergy. The aim of the present study was to compare the diagnostic utility of ultrasonographic findings and laboratory allergic data in non-IgE-mediated infantile gastrointestinal milk allergy.

METHODS

Sixteen cases of active non-IgE-mediated infantile gastrointestinal milk allergy, diagnosed by food elimination tests and oral food challenge tests (OFCTs) (group A), 15 cases of acute viral gastroenteritis (AGE) (group B), and 15 controls (group C) were enrolled. 1) B-mode abdominal ultrasound findings, 2) laboratory allergic data including eosinophil counts (Eos), serum IgE, and the antigen-specific lymphocyte proliferation test (ALPT) against milk protein, and 3) vessel density (VD) indirectly quantified by gastrointestinal Doppler flow at jejunum, ileum, and sigmoid colonic mucosae were evaluated and compared among the groups.

RESULTS

In the small intestine, wall thickening, dilation, mesenteric thickening, and poor peristalsis were found in 100%, 62.5%, 93.7%, and 100%, respectively, in group A. Eos, IgE, ALPT, and VD were positive in 25.0%, 0%, 87.5%, and 100%, respectively, in group A. Small intestinal VD was significantly greater in group A than in groups B (jejunum p < .001; ileum p < .001) and C (jejunum p < .001; ileum p < .001), with no significant differences between groups B and C (jejunum: p = .74; ileum: p = .73).

CONCLUSIONS

Abdominal Doppler ultrasonography and small intestinal VD at symptomatic state can support the diagnosis and evaluation of non-IgE-mediated infantile gastrointestinal milk allergy with symptoms of vomiting, diarrhea, and failure to thrive.

Severity scales of non-IgE-mediated gastrointestinal food allergies in neonates and infants

BACKGROUND

Non-IgE-mediated gastrointestinal food allergies (non-IgE-GI-FAs) are one type of food allergy found in neonates and infants. Few reports have defined the severity of non-IgE-GI-FAs in these populations.

METHODS

Grading scales of the severity of non-IgE-GI-FAs according to extra-GI symptoms, such as poor weight gain, as well as systemic symptoms, including fever and shock, were developed and retrospectively applied to patients with non-IgE-GI-FAs. The relationship between the severity of non-IgE-GI-FAs and both clinical and laboratory findings were examined.

RESULTS

Elevation of C-reactive protein levels and a decrease in total protein and albumin were observed in accordance with allergy severity. In an endoscopic examination, inflammatory findings were confirmed in large areas of the colonic mucosa in case of higher severity levels, and infiltration of inflammatory cells other than eosinophils was found in the severest grade. Extensively hydrolyzed milk or amino acid-based milk was required for all patients with the severest grade. In addition, the timing of acquiring tolerance tended to be late for this grade.

CONCLUSIONS

Classification and determination of the severity of non-IgE-GI-FAs in neonates and infants may not only contribute to elucidation of the pathogenesis but may also be useful in the clinical setting.

Food Protein-Induced Enterocolitis Syndrome and Proctocolitis

Non-IgE-mediated, also labeled cell-mediated, allergic reactions to foods are more common than usually thought and probably account for approximately more than 40% of cases of cow’s milk allergy during infancy and young childhood. Food allergy is now described in the form of syndromes, among which food protein-induced enterocolitis syndrome (FPIES) and food protein-induced allergic proctocolitis (FPIAP) are gaining increased recognition. FPIES occurs in infancy but may also occur in older children and in adults. The dominant symptom is emesis, repetitive in the chronic FPIES form and explosive in the acute form. Acute FPIES begins 1– 4 h following ingestion of the offending food. Diarrhea is frequent, between 5 and 10 h later, and may be accompanied by lethargy and dehydration, which both characterize severity. Cow’s milk is the most frequent food trigger, followed by soy. FPIES may develop up to 1 year of age, but may also occur in the newborn, and is possible in exclusively breastfed infants, in relation with the mother’s consumption of offending foods. FPIES may occur to solid foods (grains like rice or oat, meats, fish, egg, and vegetables). When starting during infancy, FPIES has a good prognosis and disappears grossly at 2 years of age. FPIES to fish or shellfish is more frequent in older children and adults and is long lasting. International consensus guidelines for the diagnosis and management of FPIES have been published recently. FPIAP starts in the first few months of life and is typically manifested with rectal bleeding in well-appearing breastfed infants during the first months of life in reaction to cow’s milk consumed by the mother. The condition is transient but represents one of the major causes of colitis during infancy.

Food Protein-Induced Enterocolitis Instead of Necrotizing Enterocolitis? A Neonatal Intensive Care Unit Case Series

Necrotizing enterocolitis is an important disease in infants born premature. However, other disease entities present with similar signs and symptoms. This series reviews 5 atypical cases initially diagnosed as necrotizing enterocolitis that may be more consistent with food protein-induced enterocolitis. Food protein-induced enterocolitis may be underdiagnosed in this population.

Food protein-induced enterocolitis syndrome: a review of the new guidelines

Food protein-induced enterocolitis syndrome (FPIES) is a non IgE-mediated gastrointestinal food allergy that presents with delayed vomiting after ingestion primarily in infants. While the pathophysiology of FPIES is poorly understood, the clinical presentation of acute FPEIS reactions has been well characterized. The first International Consensus Guidelines for the Diagnosis and Management of Food Protein–induced Enterocolitis Syndrome were published in 2017 and reviewed epidemiology, clinical presentation, and prognosis of acute and chronic FPIES. The workgroup outlined clinical phenotypes, proposed diagnostic criteria, and made recommendations on management. This article summarizes the guidelines and adds recent updates. FPIES is gaining recognition, however there continues to be delays in diagnosis and misdiagnosis due to overlap of symptoms with over conditions, lack of a diagnostic test, and because some of the common trigger foods are not thought of as allergenic. More research into disease mechanisms and factors influencing differences between populations is needed.

Non-IgE-mediated Adverse Food Reactions

PURPOSE OF REVIEW

The purpose of this review is to update what is currently known about the major non-IgE-mediated food allergies: food protein-induced enterocolitis syndrome (FPIES), food protein-induced allergic proctocolitis (FPIAP), and food protein-induced enteropathy (FPE). These conditions are similar in that symptoms are regulated to the gastrointestinal tract; therefore understanding their specific features is important for diagnosis and management.

RECENT FINDINGS

The most progress has been made in understanding FPIES with several recent large cohorts being described. The first international consensus guidelines for FPIES were published in 2017 and propose specific diagnostic criteria for acute FPIES as well as guidance for diagnosing chronic FPIES. Recent studies in FPIAP have challenged our thinking about the recommended duration of food avoidance and that cow's milk avoidance is the primary management with reports of self-resolution without dietary management. FPE continues to appear to be on the decline. FPIES, FPIAP, and FPE are distinguished from one another by their main clinical features: delayed repetitive vomiting in FPIES, benign blood in stool in FPIAP, and chronic diarrhea in FPE. Due to the risk of nutritional deficiencies with food avoidance in both infant and maternal diets if breastfeeding, confirmation of diagnosis with challenges is encouraged. Additional studies are needed for these conditions to elucidate pathophysiology, search for diagnostic markers, and understand natural history.

A systematic review of food protein-induced enterocolitis syndrome from the last 40 years

OBJECTIVE

To provide a complete, exhaustive summary of current literature relevant to food protein-induced enterocolitis syndrome (FPIES).

DATA SOURCES

Data have been extracted from PubMed and Science Direct databases.

STUDY SELECTIONS

Following the Preferred Reporting Items for Systematic Reviews and Meta-analysis guidelines, a literature search for peer-reviewed journal articles in English through January 1975 with updates through October 2016 was conducted. Relevant publications were reviewed that included pediatric and adult populations. Information on the study design, sample, intervention, comparators, outcome, timeframe, and risk of bias were abstracted for each article.

RESULTS

Of 135 reviewed reports, 52 were included in this systematic review. In accordance with the age at onset, clinical features, and offending foods, it is possible to distiguish different types of FPIES. An immune systemic involvement can occur in patients with FPIES. In addition to the most common causative foods (cow's milk, soy, and rice), any food can potentially cause FPIES. Although specific diagnostic tests are not available, open food challenge remains the gold standard for FPIES diagnosis. Moreover, because of the lack of randomized clinical trials and of use of different adopted methods, confounding factors might mask critical findings, leading to poor knowledge of this pleiotropic clinical entity.

CONCLUSION

Multicenter studies are needed to better develop an evidence-based approach to pathophysiology, prevalence, diagnosis, and natural history of the disease.

Japanese guidelines for food allergy 2017

Five years have passed since the Japanese Pediatric Guideline for Food Allergy (JPGFA) was first revised in 2011 from its original version. As many scientific papers related to food allergy have been published during the last 5 years, the second major revision of the JPGFA was carried out in 2016. In this guideline, food allergies are generally classified into four clinical types: (1) neonatal and infantile gastrointestinal allergy, (2) infantile atopic dermatitis associated with food allergy, (3) immediate-type of food allergy (urticaria, anaphylaxis, etc.), and (4) special forms of immediate-type of food allergy such as food-dependent exercise-induced anaphylaxis and oral allergy syndrome (OAS). Much of this guideline covers the immediate-type of food allergy that is seen during childhood to adolescence. Infantile atopic dermatitis associated with food allergy type is especially important as the onset of most food allergies occurs during infancy. We have discussed the neonatal and infantile gastrointestinal allergy and special forms of immediate type food allergy types separately. Diagnostic procedures are highlighted, such as probability curves and component-resolved diagnosis, including the recent advancement utilizing antigen-specific IgE. The oral food challenge using a stepwise approach is recommended to avoid complete elimination of causative foods. Although oral immunotherapy (OIT) has not been approved as a routine treatment by nationwide insurance, we included a chapter for OIT, focusing on efficacy and problems. Prevention of food allergy is currently the focus of interest, and many changes were made based on recent evidence. Finally, the contraindication between adrenaline and antipsychotic drugs in Japan was discussed among related medical societies, and we reached an agreement that the use of adrenaline can be allowed based on the physician's discretion. In conclusion, this guideline encourages physicians to follow the principle to let patients consume causative foods in any way and as early as possible.

Eosinophilia in infants with food protein-induced enterocolitis syndrome in Japan

BACKGROUND

Many Japanese infants with food protein-induced enterocolitis syndrome (FPIES) show eosinophilia, which has been thought to be a characteristic of food protein-induced proctocolitis (FPIP).

METHODS

To elucidate the characteristics of eosinophilia in Japanese FPIES patients, 113 infants with non-IgE-mediated gastrointestinal food allergy due to cow's milk were enrolled and classified into FPIES (n = 94) and FPIP (n = 19).

RESULTS

The percentage of peripheral blood eosinophils (Eo) was increased in most FPIES patients (median, 7.5%), which was comparable with that in FPIP patients (9.0%). Among FPIES patients, Eo was the highest in patients who had vomiting, bloody stool, and diarrhea simultaneously (12.9%) and lowest in patients with diarrhea alone (3.2%). Eo showed a significant positive correlation with the incidence of vomiting (Cramer's V = 0.31, p < 0.005) and bloody stool (Cramer's V = 0.34, p < 0.0005). A significant difference was found in Eo between early- (≤10 days, n = 56) and late-onset (>10 days, n = 38) FPIES (median, 9.8% vs. 5.4%; p < 0.005). IL-5 production by peripheral blood T cells stimulated with cow's milk protein in early-onset FPIES was significantly higher than that in late-onset FPIES (67.7 pg/mL vs. 12.5 pg/mL, p < 0.01), and showed a significant positive correlation with Eo (rs = 0.60, p < 0.01).

CONCLUSIONS

This study demonstrated two types of eosinophilia in Japanese FPIES infants: conspicuous and mild eosinophilia in early- and late-onset FPIES patients, respectively. Conspicuous eosinophilia in early-onset FPIES is suggested to be caused by abnormally high IL-5 production.

International consensus guidelines for the diagnosis and management of food protein-induced enterocolitis syndrome: Executive summary-Workgroup Report of the Adverse Reactions to Foods Committee, American Academy of Allergy, Asthma & Immunology

Food protein-induced enterocolitis (FPIES) is a non-IgE cell- mediated food allergy that can be severe and lead to shock. Despite the potential seriousness of reactions, awareness of FPIES is low; high-quality studies providing insight into the pathophysiology, diagnosis, and management are lacking; and clinical outcomes are poorly established. This consensus document is the result of work done by an international workgroup convened through the Adverse Reactions to Foods Committee of the American Academy of Allergy, Asthma & Immunology and the International FPIES Association advocacy group. These are the first international evidence-based guidelines to improve the diagnosis and management of patients with FPIES. Research on prevalence, pathophysiology, diagnostic markers, and future treatments is necessary to improve the care of patients with FPIES. These guidelines will be updated periodically as more evidence becomes available.