What is the evaluation for Food Protein-Induced Enterocolitis Syndrome (FPIES)?

From the Guidelines

To evaluate for Food Protein-Induced Enterocolitis Syndrome (FPIES), a combination of clinical history, physical examination, and specific diagnostic tests is recommended, with a focus on a detailed medical history and oral food challenge (OFC) as the gold standard for diagnosis, as stated in the 2017 international consensus guidelines 1. Start with a detailed medical history, focusing on food intake and timing of symptoms, looking for characteristic symptoms like repetitive vomiting, diarrhea, and lethargy occurring 1-4 hours after ingesting the suspected food trigger. Perform a physical examination to assess for signs of dehydration, abdominal distension, or failure to thrive. Diagnostic tests include:

• Complete blood count (CBC) to check for elevated white blood cell count and thrombocytosis
• Metabolic panel to assess electrolyte imbalances
• Stool analysis to rule out infectious causes An oral food challenge (OFC) is the gold standard for diagnosis, which should be performed under medical supervision, as severe reactions can occur, and introduce the suspected food trigger at a dose of 0.06 to 0.6 g, usually 0.3 g of the food protein per kilogram of body weight, in 3 equal doses over 30 minutes, and monitor for symptoms for 4-6 hours, as recommended in the guidelines 1. Skin prick tests and specific IgE blood tests are typically negative in FPIES, which helps differentiate it from IgE-mediated food allergies, and understanding FPIES's non-IgE mediated nature explains why traditional allergy tests are often negative, as noted in the 2010 guidelines for the diagnosis and management of food allergy in the United States 1. Avoid endoscopy or colonoscopy as initial diagnostic tools, as they are invasive and not specific for FPIES. Some key points to consider in the evaluation of FPIES include:
• The importance of a careful medical history in diagnosing FPIES, as stated in the 2017 international consensus guidelines 1
• The use of OFC as the gold standard for diagnosis, with caution and close supervision, as recommended in the guidelines 1
• The need to rule out other potential causes of symptoms, such as infectious gastroenteritis, sepsis, and necrotizing enterocolitis, as listed in the differential diagnosis table in the 2017 guidelines 1
• The importance of considering the non-IgE mediated nature of FPIES and the delayed onset of symptoms, as noted in the 2010 guidelines 1.

From the Research

Evaluation of Food Protein-Induced Enterocolitis Syndrome (FPIES)

The evaluation of FPIES involves several key considerations, including:

• Clinical presentation: FPIES typically presents with delayed onset of vomiting, diarrhea, and lethargy/dehydration, usually 1-4 hours after ingestion of the offending food 2, 3, 4.
• Diagnosis: The diagnosis of FPIES relies on the recognition of symptoms, as there are no biomarkers for the condition 2, 3, 4.
• Food triggers: Common food triggers for FPIES include cow's milk, soy, grains, vegetables, and poultry, although any food can potentially cause FPIES 5, 2, 3, 6, 4.
• Patient history: A thorough patient history is essential in evaluating FPIES, including dietary history and any previous reactions to foods 5, 6.

Diagnostic Approach

The diagnostic approach for FPIES may involve:

• Oral food challenge (OFC): An OFC may be used to confirm the diagnosis of FPIES and to assess tolerance to specific foods 3, 4.
• Elimination diet: An elimination diet may be used to identify the offending food and to manage symptoms 3.
• Clinical evaluation: A clinical evaluation, including physical examination and medical history, is essential in diagnosing FPIES 5, 2, 3, 6, 4.

Management and Treatment

The management and treatment of FPIES involve:

• Dietary avoidance: Avoidance of the offending food is essential in managing FPIES 2, 3, 4.
• Rehydration: Rehydration is critical in managing acute reactions to FPIES 4.
• Antiemetic medication: Antiemetic medication, such as ondansetron, may be used to manage nausea and vomiting 4.
• Periodic re-evaluations: Periodic re-evaluations with OFC are necessary to monitor for resolution of FPIES 3, 4.