Food protein-induced enterocolitis syndrome caused by solid food proteins

Background. Infantile food protein-induced enterocolitis syndrome (FPIES) is a severe, cell-mediated gastrointestinal food hypersensitivity typically provoked by cow's milk or soy. Solid foods are rarely considered a cause. Objective. To describe the clinical characteristics and natural history of FPIES provoked by solid foods. Methods. Patients with FPIES induced by solid foods were identified and their clinical course compared with a control group with FPIES caused by cow's milk and/or soy evaluated over the same time period. Results. Fourteen infants with FPIES caused by grains (rice, oat, and barley), vegetables (sweet potato, squash, string beans, peas), or poultry (chicken and turkey) were identified. Symptoms were typical of classical FPIES with delayed (median: 2 hours) onset of vomiting, diarrhea, and lethargy/dehydration. Eleven infants (78%) reacted to >1 food protein, including 7 (50%) that reacted to >1 grain. Nine (64%) of all patients with solid food FPIES also had cow's milk and/or soy-FPIES. Initial presentation was severe in 79% of the patients, prompting sepsis evaluations (57%) and hospitalization (64%) for dehydration or shock. The diagnosis of FPIES was delayed, after a median of 2 reactions (range: 2-5). Thirty patients with typical cow's milk- and/or soy-FPIES were identified for comparison. Overall, 48% of the 44 infants with FPIES were reactive to >1 food protein, and the risk for multiple food hypersensitivity approached 80% in the infants with solid food or soy-induced FPIES. None of the patients developed FPIES to maternally ingested foods while breastfeeding unless the causal food was fed directly to the infant. Conclusions. Cereals, vegetables, and poultry meats, typically regarded as of low allergenic potential, must be considered in the evaluation of FPIES, particularly in infants previously diagnosed with FPIES to cow's milk or soy, and as an initial cause in patients who have been exclusively breastfed. Infants with FPIES are at risk for multiple dietary protein hypersensitivities during an apparent period of immunologic susceptibility. Pediatricians should consider FPIES in the differential diagnosis of shock and sepsis.