Clinical Manifestations of FPIES


Acute and Chronic Food Protein-Induced Enterocolitis Syndrome (FPIES) may present in either acute or chronic form:


Acute FPIES occurs when the trigger food is ingested on an intermittent basis or if it is re- introduced following a period of avoidance. Symptoms begin 1 to 3 hours after ingestion, typically with somewhat more severe presentation than chronic FPIES. In addition to profuse emesis (which may be projectile and occur up to 10-20 times) and dehydration, infants may develop lethargy, pallor, dusky appearance, hypotension (15-20%), and hypothermia. Minority report diarrhea with acute FPIES episodes; diarrhea seems to be more common in younger infants and with more severe reactions.


Chronic FPIES occurs with frequent/daily ingestion of the trigger food, and typically presents in formula-fed infants in the first weeks of life, with symptoms of intermittent emesis, watery or mucous diarrhea, poor weight gain, and dehydration. There are no classic allergic symptoms from the skin (e.g., hives, itching, swelling) or respiratory tract (e.g., sneezing, cough, wheezing) in either form of FPIES.

Regarding chronic FPIES, there appears to be some confusion among the providers and the parents of children with chronic gastrointestinal symptoms. Based on our experience from a referral population, the diagnosis of chronic FPIES is considered when all other diagnostic labels don’t fit. It is sometimes given to children with ongoing gastrointestinal symptoms that persist despite extensive dietary eliminations or while the child is exclusively fed with an amino acid-based formula. In such cases, supervised oral food challenges are necessary to confirm the diagnosis of FPIES and to avoid misdiagnosing other conditions (e.g., metabolic disorders, eosinophilic gastroenteropathies or gastrointestinal inflammatory diseases) as chronic FPIES.


The FPIES phenotype had originally been defined in young infants reacting to milk or soy proteins. They had chronic symptoms of vomiting, diarrhea, sometimes with failure to thrive, and/or bloody stools while being fed with milk or soy-based formulas in the first months of life. Following removal of the formula due to severe symptoms requiring hospitalization, symptoms resolved within a few days. However, subsequent reintroduction of the formula resulted in the typical pattern of acute FPIES, with the onset of emesis in 2-4 hours following a feeding.


Provided by the I-FPIES Medical Advisory Board, September 2014.. 

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