Definition, etiology, and diagnosis of food protein-induced enterocolitis syndrome.

PURPOSE OF REVIEW: Food protein-induced enterocolitis syndrome (FPIES) is a poorly understood non-IgE-mediated food hypersensitivity, primarily affecting infants and toddlers. There are few data regarding pathophysiology of FPIES that suggest local intestinal imbalance between TNF-α and TGF-ß. Patients frequently present with multiple reactions, which are characterized by projectile, repetitive emesis, dehydration, lethargy, and failure to thrive. Despite the severity of presentation, the diagnosis is frequently delayed, and patients often undergo extensive and invasive evaluation prior to reaching the diagnosis. RECENT FINDINGS: Reviews published in the last year provide a general approach to diagnosis and management of FPIES and aim to increase awareness and understanding of FPIES among general pediatricians. SUMMARY: Multicenter studies are necessary to reevaluate and modify the oral food challenge criteria. Research on the pathophysiology of FPIES reactions is necessary to provide insight into the evidence-based approach to diagnosis and management of FPIES. Registries are needed to understand the phenotype, triggers, and prevalence of FPIES.

Gastrointestinal food allergy in infants.

Food allergies are classified into three types, "IgE-mediated," "combined IgE- and cell-mediated" and "cell-mediated/non-IgE-mediated," depending on the involvement of IgE in their pathogenesis. Patients who develop predominantly cutaneous and/or respiratory symptoms belong to the IgE-mediated food allergy type. On the other hand, patients with gastrointestinal food allergy (GI allergy) usually develop gastrointestinal symptoms several hours after ingestion of offending foods; they belong to the cell-mediated/non-IgE-mediated or combined IgE- and cell-mediated food allergy types. GI allergies are also classified into a number of different clinical entities: food protein-induced enterocolitis syndrome (FPIES), food protein-induced proctocolitis (FPIP), food protein-induced enteropathy (Enteropathy) and eosinophilic gastrointestinal disorders (EGID). In the case of IgE-mediated food allergy, the diagnostic approaches and pathogenic mechanisms are well characterized. In contrast, the diagnostic approaches and pathogenic mechanisms of GI allergy remain mostly unclear. In this review, we summarized each type of GI allergy in regard to its historical background and updated clinical features, offending foods, etiology, diagnosis, examinations, treatment and pathogenesis. There are still many problems, especially in regard to the diagnostic approaches for GI allergy, that are closely associated with the definition of each disease. In addition, there are a number of unresolved issues regarding the pathogenic mechanisms of GI allergy that need further study and elucidation. Therefore, we discussed some of the diagnostic and research issues for GI allergy that need further investigation.