Author: V. Dimov, M.D., Allergist/Immunologist and Assistant Professor at University of Chicago
Reviewer: S. Randhawa, M.D., Allergist/Immunologist and Assistant Professor at NSU
Food Protein–Induced Enterocolitis Syndrome (FPIES) is a non–IgE-mediated food allergy that most commonly affects infants. Cow’s milk and soy FPIES resolve in most patients by 3 years of age, patients with solid food FPIES and/or detectable food specific IgE levels may have more protracted courses.
One approach to FPIES diagnosis is follow-up challenges every 18 to 24 months in patients without recent reactions.
Food Protein–Induced Enterocolitis Syndrome Oral Food Challenge Protocol. Source: Food protein–induced enterocolitis syndrome: an update on natural history and review of management. JACI, 08/2011.
- Basic requirements: physician supervision, secure intravenous (IV) access, immediate availability of fluid resuscitation
- Baseline vital signs and peripheral neutrophil count (repeat CBC-Diff in 6 hours)
- Gradual (during 1 hour) administration of food protein 0.06 – 0.6 g/kg body weight in 3 equal doses, generally not to exceed total 3 g of protein or 10 g of total food (100 mL of liquid) for an initial feeding
- If no reaction in 2–3 hours, administer an age-appropriate serving of the food followed by several hours of observation
- Fluid resuscitation: 20 mL/kg IV boluses of normal saline
- Steroids: methylprednisolone, 1 mg/kg IV (maximum, 60 – 80 mg)
- Most patients (more than 50%) with positive challenge results require treatment with intravenous fluids and steroids
An FPIES OFC is considered a high-risk procedure and should be conducted in a setting where intravenous access can be secured and rapid fluid resuscitation given if a reaction occurs. Although an inpatient setting is the most appropriate for FPIES OFCs, outpatient settings equipped with resuscitation capabilities with access to a laboratory (for neutrophil counts and stool analysis) can be used.
For the first serving, doses are administered in 3 portions during 45– 60 minutes for a total of 0.06 to 0.6 g/kg of food protein, starting at a lower dose in patients with a history of severe reactions.
The total amount does not generally exceed 3 to 6 g or 10 to 20 g of total food weight (100 mL of total liquid). If the patient is asymptomatic after 2 to 3 hours, then an age-appropriate serving is usually given as a second serving and the patient is observed for several more hours. First-line therapy in the event of a positive challenge result is rapid intravenous hydration of normal saline given in 20 mL/kg boluses. Intravenous corticosteroids may also be used in severe reactions. Epinephrine should be available.
The challenge is considered positive if typical symptoms and laboratory findings are present:
- Emesis (onset, 1–3 hours)
- Diarrhea (onset, 2–10 hours; mean, 5 hours)
- Lethargy (onset, 1–3 hours)
- Laboratory findings:
Elevated neutrophil count (more than 3500/mcL, peaks at 6 hours)
Frank or occult fecal blood
Fecal leukocytes, red blood cells, and/or eosinophils
Gastric juice leukocytosis (>10 leukocytes per high-power field, at 3 hours)
A complete blood count with differential should be measured prior to challenge, and approximately 6 hours after challenge if there are symptoms. If diarrhea is present, stool guaiac test should be performed and stool samples tested for fecal leukocytes, red blood cells, and eosinophils.
Food Protein–Induced Enterocolitis Syndrome Oral Food Challenge Protocol. Source: Food protein–induced enterocolitis syndrome: an update on natural history and review of management. JACI, 08/2011, http://goo.gl/LlwRU
Food Protein-Induced Enterocolitis Syndrome: Consensus Recommendations for Diagnosis and Treatment Japanese Research Group for Neonatal, Infantile Allergic Disorders, 2011, http://goo.gl/TmdFo
What is FPIES (Food Protein Induced Enterocolitis Syndrome)? http://goo.gl/fTP3O
Food protein-induced enterocolitis syndrome (FPIES) - AAAAI Ask the Expert http://goo.gl/J9aS5
Oral food challenges for diagnosis and management of food allergies - UpToDate http://goo.gl/LtRvE