Food Protein-Induced Enterocolitis Syndrome (FPIES) and Milk and Soy Protein Intolerance (MSPI) present unique challenges for families, especially when affecting infants and young children. These conditions are not food allergies as we typically think of them and cannot be tested for using IgE blood tests or skin prick tests. 

Food Protein-Induced Enterocolitis Syndrome (FPIES)

When most people talk about food allergies, they are talking about IgE-mediated food allergies. IgE is a specific antibody in the immune system that triggers the familiar symptoms of an allergic reaction. However, not all allergies are mediated by this specific antibody – these allergies are referred to as “non-IgE mediated,” and can’t be diagnosed or treated the same way IgE-mediated allergies can. However, unlike sensitivities or intolerances, these allergies still involve the immune system.

FPIES, or food protein-induced enterocolitis syndrome, is a non-IgE mediated allergy. FPIES symptoms are usually limited to gastrointestinal symptoms. It differs from traditional (IgE-mediated) allergies, as it does not cause immediate symptoms like itching or swelling. Instead, it leads to vomiting and diarrhea. Common triggers include cow's milk and soy, but any food, even those that don’t typically cause allergies like rice or oat, can cause a reaction.

FPIES reactions often emerge in the first weeks or months of life, especially with the introduction of solid foods. Symptoms, ranging from mild reflux to severe dehydration and shock, typically appear a few hours after ingestion.

Diagnosing FPIES can be challenging, relying on symptom presentation as standard allergy tests may not reveal the condition. Therefore, it is important to work with a physician to understand the symptoms and their cause. During an FPIES reaction, immediate medical attention is crucial. Treatment involves intravenous (IV) fluids to combat dehydration, and in severe cases, steroids may be administered. While epinephrine is not typically required, it might be prescribed in specific cases.

Typically, FPIES is not a lifelong condition. Many children outgrow it by the age of 3, although the timeline varies. Trigger foods should be reintroduced cautiously under medical supervision.

Milk and Soy Protein Intolerance (MSPI)

MSPI, or milk and soy protein intolerance, is a common food-related intolerance in infants, affecting around 85,000 infants annually. It is triggered by proteins found in milk and soy. Another term, Cow's Milk Protein Intolerance (CMPI), specifically refers to intolerance to cow's milk protein.

MSPI and FPIES both involve protein intolerance, but MSPI reactions are not as severe or immediate. While FPIES triggers a systemic response with symptoms appearing within a few hours, MSPI may result in colic, vomiting, diarrhea, and blood in stools 4 – 24 hours after eating the trigger food. Both of these reactions are significantly more delayed than IgE-mediated reactions, which usually occur within minutes

Diagnosis involves recognizing symptoms and may require consultation with a physician. Both conditions highlight the need to be vigilant about hidden traces of protein in various products.

Navigating the challenges of FPIES and MSPI requires understanding the unique characteristics of each condition. Seeking timely medical advice and closely monitoring a child's diet can contribute to effective management and, in many cases, the eventual outgrowing of these conditions.

All health-related content on this website is for informational purposes only and does not create a doctor-patient relationship. Always seek the advice of your own pediatrician in connection with any questions regarding your baby’s health.

These statements have not been evaluated by the Food and Drug Administration and are not intended to diagnose, treat, cure or prevent any disease.