Food protein‐induced enterocolitis syndrome: Pitfalls in the diagnosis

Food protein‐induced enterocolitis syndrome (FPIES) represents the severe end of the spectrum of gastrointestinal food hypersensitivity; its acute episodes can culminate in severe dehydration and hypovolemic shock, and its chronic form entails considerable morbidity associated with feeding difficulty and failure to thrive. Nevertheless, awareness for this syndrome remains rather low. Many factors hamper the establishment of FPIES diagnosis. Such factors pertain to the pathophysiological mechanism of the syndrome, causal food proteins, clinical manifestations, diagnostic procedures, differential diagnosis considerations, and prevailing perceptions which may require critical appraisal. Throughout this review, we will present and discuss these issues and put the focus on factors that could lead to under‐diagnosis of FPIES, cause numerous acute episodes, and substantially increase the diseases morbidity and financial burden. We will also address other issues that are clinically relevant to FPIES.     

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.     

Non‐IgE‐mediated gastrointestinal food allergies in children

Non‐IgE‐mediated gastrointestinal food allergic disorders (non‐IgE‐GI‐FA) including food protein‐induced enterocolitis syndrome (FPIES), food protein‐induced enteropathy (FPE), and food protein‐induced allergic proctocolitis (FPIAP) are relatively uncommon in infants and young children, but are likely under‐diagnosed. Non‐IgE‐GI‐FA have a favorable prognosis, with majority resolving by age 3–5 years. Diagnosis relies on the recognition of symptoms pattern in FPIAP and FPIES and biopsy in FPE. Further studies are needed for a better understanding of the pathomechanism, which will lead eventually to the development of diagnostic tests and treatments. Limited evidence supports the role of food allergens in subsets of constipation, gastroesophageal reflux disease, irritable bowel syndrome, and colic. The immunologic pathomechanism is not fully understood and empiric prolonged avoidance of food allergens should be limited to minimize nutrient deficiency and feeding disorders/food aversions in infants.     

Food protein-induced enterocolitis syndrome – not only due to cow's milk and soy

Over a of 7-year period, six patients (four males, two females aged 3–12 months) were diagnosed with food protein-induced enterocolitis syndrome (FPIES) triggered by foods other than cow's milk and soy: chicken in four, turkey in two, peas in one, and lentils in one (five patients reacted to more than one food type). All reactions developed within 2 h of ingestion of the allergenic food. To exclude other conditions with similar clinical symptoms, three infants underwent work-up for sepsis, one infant underwent work-up to exclude metabolic defects, and one underwent a barium enema to rule out intussusception. All were negative. Pediatricians should be aware that FPIES may be caused by foods other than cow's milk and soy, mainly chicken, turkey and foods from the legume family, and that it may present also in infants older than 6 months.     

Practical approach to nutrition and dietary intervention in pediatric food allergy

Although the need for nutritional and dietary intervention is a common thread in food allergy management, the type of food allergic disorder and the identified food allergen will influence the approach to dietary intervention. A comprehensive nutrition assessment with appropriate intervention is warranted in all children with food allergies to meet nutrient needs and optimize growth. However, dietary elimination in food allergy may also have undesirable consequences. Frequently, an elimination diet is absolutely necessary to prevent potentially life‐threatening food allergic reactions. Allergen elimination can also ease chronic symptoms, such as atopic dermatitis, when a food is proven to trigger symptoms. However, removing a food with proven sensitivity to treat chronic symptoms may increase the risk of an acute reaction upon reintroduction or accidental ingestion after long‐term avoidance, so it is not without risk. Additionally, it is not recommended to avoid foods in an attempt to control chronic symptoms such as AD and EoE when allergy to the specific food has not been demonstrated. Ultimately, allergen elimination goals are to prevent acute and chronic food allergic reactions in the least restrictive, but also the safest environment to supply a balanced diet that promotes health and growth and development in children.