Food Protein Induced Enterocolitis Syndrome (FPIES)

Rare diseases are not confined to the pages of a textbook or computer screen. Our patients have varied past medical histories that require us to be well-versed in even the most uncommon disorders (or know where to look things up in a pinch)! Today we are talking about a rare disease called FPIES (food protein induced enterocolitis syndrome) and how you might encounter these patients in the Pediatric Emergency Department. 

Food Protein Induced Enterocolitis Syndrome (FPIES): Basics

  • Non IgE-mediated food allergy (Calvani, 2021)
  • Profuse vomiting and diarrhea that can progress to lethargy, pallor, and shock
  • Usually seen in infants (<1 year) as new foods are being introduced in diet
    • Common dietary triggers include grains, cow milk and soy (Michelet, 2017)
    • Can also be seen with rice, chicken and potatoes (Michelet, 2017)
  • Diagnosis is based on clinical symptoms, removal of offending agent, and oral food challenge (OFC) resulting in recurrent symptoms (Wong, 2022)
  • Prevalence estimation = 1/10,000 to 0.75%; however believed to be under-diagnosed (Michelet, 2017)
  • Usually due to a single food, but up to 1/3 have multiple food triggers (Wong, 2022)
  • Often resolves by the age of 5 years.

Food Protein Induced Enterocolitis Syndrome (FPIES): Evaluation

  • Presentation (Michelet, 2017)
    • Occurs roughly 2-3 hours after eating offending food
    • Profuse vomiting progressing to diarrhea
    • Can present with significant activity change and lethargy
    • If severe, can progress to hypovolemic shock 
  • Laboratory 
    • No specific laboratory marker
    • Dehydrated children may have laboratory findings of pre-renal acute kidney injury and low bicarbonate 

Food Protein Induced Enterocolitis Syndrome (FPIES): Management

  • Acute management 
    • Depending on severity of symptoms patients will require oral vs IV hydration
    • Zofran for nausea
    • Perform thorough physical examination with careful attention to possible abdominal emergencies!
  • Admission to hospital depending on severity of symptoms and need for further hydration 

Moral of the Morsel

  • Diseases, just like our patients, are unique and varied! 
  • It may sound silly (“FPIES”), but it can be serious! Patients with FPIES can have marked dehydration due to vomiting and diarrhea, even to the point of hypotension! 
  • Volume Status?! – As always, treat symptoms and dehydration based on severity.
  • You may not make the diagnosis, but detecting the clues is important for the family! Although we probably will not be the ones to diagnose FPIES in an emergency department, counseling patients and their families on keeping a food diary, can help them in the future to make the diagnosis (even in patients you suspect have gastroenteritis!). 


  • Calvani M, Anania C, Bianchi A, D’Auria E, Cardinale F, Votto M, Martelli A, Tosca M, Chiappini E, Brambilla I, Miraglia Del Giudice M, Caffarelli C. Update on Food protein-induced enterocolitis syndrome (FPIES). Acta Biomed. 2021 Nov 29;92(S7):e2021518. doi: 10.23750/abm.v92iS7.12394. PMID: 34842596; PMCID: PMC9431892.
  • Michelet M, Schluckebier D, Petit LM, Caubet JC. Food protein-induced enterocolitis syndrome – a review of the literature with focus on clinical management. J Asthma Allergy. 2017 Jun 27;10:197-207. doi: 10.2147/JAA.S100379. PMID: 28721077; PMCID: PMC5499953.
  • Wong, S., Duan, L., Galper, A. et al. Food protein-induced enterocolitis syndrome in a tertiary pediatric center: safety of guideline-conforming food challenges. Allergy Asthma Clin Immunol 18, 54 (2022).
Ali Rosser
Ali Rosser
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