FPIES – Food Protein-Induced Enterocolitis Syndrome

Tween boy sitting at a lunchtable with an empty dish next to him. His hands are on his face in a stressed mood.

Is your child experiencing sudden bouts of vomiting and diarrhea after eating food? Are symptoms so severe and chronic that you need to take your child to the emergency department?

Your doctor may evaluate your child  for food protein-induced enterocolitis syndrome, also called FPIES.

What is FPIES?

FPIES is a severe type of food reaction. It is a rare disease primarily affecting infants and young children. (There are possible cases of FPIES in adults.)

FPIES is not similar to food allergies. A food allergy is IgE-mediated, meaning that allergy antibodies cause the reaction. FPIES is a non-IgE-mediated reaction. Symptoms occur in the gastrointestinal system. They are often delayed for 1-4 hours after eating the triggering food.

An FPIES diagnosis cannot be done using traditional food allergy testing. Instead, an oral food challenge may help identify which food(s) are triggering symptoms.

What foods trigger FPIES?

Any food protein is potentially an FPIES trigger, but the most common FPIES reactions are due to:

  • milk (including infant formula)
  • soy
  • rice and oats
  • grains

Some children may react to chicken, turkey and fish.

Most children react to just one food. Some others may react to multiple foods. It’s also possible for some infants to experience reactions to breast milk.

Adults report that they develop FPIES symptoms most often after eating shellfish.

When do FPIES symptoms start?

Food allergy reactions are often immediate. FPIES reactions are delayed. They typically begin between 1-4 hours after eating the trigger food.

What are acute FPIES symptoms?

Acute FPIES reactions include:

  • vomiting
  • diarrhea
  • dehydration
  • fatigue

In about 20% of cases, the child will experience a severe reaction leading to shock. The child may require emergency intravenous fluids for rehydration. In rare cases, intravenous steroids may be used to reverse the effects of shock.

What are chronic FPIES symptoms?

Chronic FPIES reactions involve similar symptoms to acute reactions. With diarrhea, there may be blood or mucus in the stool). Chronic FPIES may also involve weight loss – and in the most severe cases, an inability to gain weight.

How is FPIES diagnosed?

An FPIES diagnosis is made after considering the child’s history of symptoms and exclusion of other conditions, including food allergies. The primary test for FPIES is food trial and error in medically supervised oral food challenges.

Delayed diagnosis and misdiagnosis of FPIES are common. Symptoms might initially suggest a stomach virus.

What is the treatment for FPIES?

To treat a severe reaction, the child should be seen immediately by a doctor to avoid shock. Severe symptoms may require medical treatment involving intravenous fluids to help with dehydration. Excessive vomiting and diarrhea can also lead to imbalances in the body’s electrolytes.

Corticosteroids may be administered to help reduce the severity of the reaction. They won’t treat the condition, however.

There is no cure for FPIES. Once the food trigger is identified, strict avoidance of that food is necessary.

Parents should work with their doctor and a dietitian to develop a personalized diet plan that ensures proper nutrition. A hypoallergenic formula diet is recommended. There are two types:

  • amino acid-based elemental formula
  • extensively hydrolyzed casein or whey formula

For infants with growth issues or multiple food triggers, doctors typically recommend the amino acid-based formula.

If extensive hydrolyzed formula is recommended, keep in mind that between 10-12% of infants do not tolerate it. Parents should contact their doctor if their child is not tolerating the formula.

These formulas can be quite expensive and insurance coverage varies by state.

FPIES can significantly impact quality of life. It may take time to diagnose. It may be challenging to figure out food triggers. This can become a social, emotional and financial burden on those affected, as well as their families. Ongoing advocacy for research into FPIES and support for those affected is important.

Can you outgrow FPIES?

Many children outgrow FPIES between the ages of 1 and 3. For some it may last until ages 6 or 7; for others, it is a lifelong condition.

Patient Story: Amanda, Nick and Matthew’s Story

Written by Amanda Bofferding of Cedar Park, Texas:

I was excited to start my son Matthew on solid foods when he was 6 months old. It started well until I fed him rice cereal. Two hours later, he was vomiting every few minutes.

A week later, I tried feeding him rice cereal again. Two hours later, more vomiting. I was worried. I knew something was wrong.

So I googled “vomit rice cereal” and discovered a disease with the acronym FPIES that mirrored Matthew’s symptoms. My husband and I took him to see an allergist and the diagnosis was confirmed: food protein-induced enterocolitis syndrome. We learned his food triggers and adjusted his diet to avoid them.

When Matthew turned 3, he underwent his first oral food challenge to determine if he had outgrown one of his triggers: dairy. He passed! Matthew was so excited, too. It was an awesome moment.

Patient Resources

FPIES Foundation: fpiesfoundation.org

International FPIES Association: fpies.org