A Rare Case of Fetal Onset, Food Protein-Induced Enterocolitis Syndrome

Background: Food protein-induced enterocolitis syndrome (FPIES) is a non-IgE-mediated food allergy. The pathological mechanism of FPIES is intestinal inflammation, and cell-mediated hypersensitivity is presumed to play an important role in its development. Case Report: The first case in which significant fetal intestinal distension suggested fetal onset of FPIES is reported. A 2,334-g male was born at 34 weeks by vaginal delivery. Results: In utero, he had significant intestinal distension on ultrasonography and MRI. A few hours after the first feeding, he produced bloody stool and showed abdominal distension. In this case, FPIES was not only caused by cow’s milk protein diagnosed clinically and by an allergen-specific lymphocyte stimulation test, but also by breast milk diagnosed by oral food challenge. The clinical course and laboratory results strongly suggested not only fetal sensitization but also fetal onset. Conclusion: This report might be helpful for prompt diagnosis and treatment and, furthermore, lead to elucidation of the pathogenesis and pathophysiology of FPIES.