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.
References:
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
Published: 05/12/2012
Updated: 08/09/2012
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