Food Protein-induced Enterocolitis Syndrome.

Food protein-induced enterocolitis syndrome (FPIES) is a type of non-IgE-mediated gastrointestinal food allergy. FPIES is characterized by repetitive vomiting without classic IgE-mediated allergic skin or respiratory symptoms 1-4 h after causative food ingestion. The condition may be classified as acute or chronic, typical or atypical, and liquid or solid according to the course of symptoms, presence of IgE antibodies, and causative food, respectively. Since the development of international consensus guidelines in 2017, epidemiological studies have been conducted in many countries. FPIES is a relatively rare disease, with a prevalence of 0.015%-0.7%. However, the number of patients has been increasing in recent years. Most patients develop the disease in infancy. The natural history of FPIES is generally favorable, with most FPIES cases resolving before school age. FPIES is diagnosed using symptoms such as vomiting or diarrhea, or via an oral food challenge (OFC). Currently, no validated biomarker is available for diagnosis, and the mechanisms related to gastrointestinal manifestations and immune system involved in the development of FPIES have not yet been elucidated. Treatment with intravenous fluids and ondansetron is recommended in the acute phase. Long-term management consists of complete causative food elimination and periodic OFC to confirm tolerance. Given that many diagnoses are delayed because of a lack of awareness of the condition, FPIES must be widely recognized by healthcare providers. In the future, it is expected that FPIES pathogenesis will be further clarified, and more objective diagnostic criteria will be developed.