Food protein-induced enterocolitis syndrome (FPIES) is a systemic, non IgE-mediated response to a specific trigger within food – most likely foodprotein. FPIES presents in two different forms: an acute form and a chronic form. In its acute form, FPIES presents with vomiting that usually begins 1 to 4 hours after trigger food ingestion (can be 30 minutes to 6 or more hours). Vomiting is often followed by a paleness to the skin, lethargy, and potentially watery, perhaps blood-tinged diarrhea. In the severe form of acute FPIES, a person will vomit until dehydration and until a shock-like state, which occurs in 15% of patients.[1] In its chronic form, which can be difficult to diagnose until a person has already met diagnostic criteria for acute FPIES, after repeated or regular ingestion of the trigger food, the person presents with chronic or episodic vomiting, failure to thrive, and watery, perhaps blood-tinged diarrhea. FPIES can potentially develop at any age but seems most commonly to develop within the first few years of life.[2][3][4][5][6] FPIES has mainly been documented in young infants, but can exist in older children and adults. Some people develop both FPIES and an IgE-mediated type of reaction to the same food, and having FPIES can increase a person's risk of also developing IgE-mediated food allergies.[7]
^Nowak-Wegrzyn A, Muraro A. Food protein-induced enterocolitis syndrome. Current Opinion in Allergy and Clinical Immunology 2009; 9:371-7. PMID:19474706