Children with acute food protein-induced enterocolitis syndrome from Spain and Italy usually tolerate all other food groups

Oral Food Challenge Protocols in Food Protein-Induced Enterocolitis Syndrome: A Systematic Review

BACKGROUND

Oral food challenges (OFCs) are essential for the diagnosis and follow-up of acute food protein-induced enterocolitis syndrome (FPIES) because no diagnostic or prognostic biomarkers are available. However, the optimal OFC procedure remains unclear.

OBJECTIVE

This systematic review aimed to assess OFC procedures' design and clinical outcomes in patients with FPIES.

METHODS

We searched 10 databases for studies published in English between 1978 and February 2024 involving children or adults undergoing OFC for FPIES. Critical appraisal followed Effective Public Health Practice Project parameters.

RESULTS

In total, 52 studies met inclusion criteria, all observational studies. Of these, 35 were judged to have strong methodological quality. There was great heterogeneity in OFC procedures, particularly in cumulative dose, number, size, and timing between doses. Oral food challenge outcome reporting was often inadequate, especially regarding reaction symptoms and severity grading. In single-dose OFC protocols, most children reacted after at least 2 hours. Four small studies showed that a single dose of 25% of an age-appropriate portion was sufficient to trigger reactions in 80% to 100% of cases, and this was associated with less severe reactions. Owing to methodological heterogeneity and insufficient outcome reporting, further assessment of the OFC protocol characteristics associated with safer outcomes was not possible.

CONCLUSIONS

There is significant heterogeneity in FPIES OFC practices. Current recommendations for OFC procedures and outcome assessments have limitations and should be revisited, because this may affect patient safety and diagnostic accuracy. Future studies should focus on standardizing clinical outcomes and generating evidence to support safer, more accurate OFC protocols in FPIES.

An update on the diagnosis and management of non-IgE-mediated food allergies in children

The spectrum of non-IgE mediated conditions includes well-defined conditions like Food Protein-Induced Enterocolitis Syndrome (FPIES), Eosinophilic Oesophagitis (EoE), Food Protein-Induced Enteropathy, and Food Protein-Induced Allergic Proctocolitis, but also the more controversial food protein-induced dysmotility disorders like food protein-induced gastroesophageal reflux disease (FPGORD) and food protein-induced constipation (FPC). Typically, non-IgE mediated reactions are delayed, with symptom onset from hours to days after exposure to a culprit food. The diagnosis is mostly clinical, and food elimination followed by reintroduction is the primary diagnostic method. Apart from EoE, the diagnosis of these conditions remains challenging, and there is a need to develop specific diagnostic tests. Acute FPIES presents with distinct symptoms, but misdiagnosis is common due to poor recognition. In contrast, some presentations, particularly FPGORD and FPC, overlap with the common, often benign disorders of gut-brain interaction, previously known as functional gastrointestinal disorders. This raises concerns about overdiagnosis and can lead to an unnecessary restrictive diet in infants and breastfeeding mothers. A systematic approach to an elimination diet and the support of a registered dietitian/nutritionist are recommended to ensure nutritional adequacy, suitable alternatives, promote timely introductions when appropriate, support breastfeeding where required as well as prevent nutritional deficiencies and feeding difficulties. This publication aims to provide an update on the spectrum of non-IgE-mediated food allergic conditions and intends to provide clinicians with practical guidance on the diagnosis and management of each condition. The authors acknowledge the need for further research in a range of areas to inform best evidence-based practice.

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.

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.

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.

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

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