What is the management plan for food protein-induced enterocolitis (FPIES)?

Management of Food Protein-Induced Enterocolitis Syndrome (FPIES)

The primary management of FPIES involves strict dietary elimination of trigger foods, appropriate emergency treatment of acute reactions, and regular monitoring for resolution under medical supervision. 1

Diagnosis and Initial Management

• FPIES typically presents with protracted, projectile vomiting 1-4 hours after ingesting trigger foods, sometimes followed by diarrhea within 24 hours
• In 15-20% of severe cases, patients may develop hypovolemic or distributive shock 2
• Common triggers include cow's milk, soy, rice, oat, avocado, egg, and peanut 2

Dietary Management

Elimination Diet

• Complete elimination of identified trigger foods is the cornerstone of FPIES management 1
• For cow's milk or soy-induced FPIES:
  • Avoid all forms including baked and processed foods
  • Goat and sheep milk are not recommended due to protein sequence homology
  • Introduction of baked milk/egg should only be done under physician supervision 1

Formula and Breastfeeding Recommendations

• Infants with cow's milk/soy-induced FPIES can be:
  • Breastfed (preferred when possible)
  • Given casein-based extensively hydrolyzed formula
  • 10-20% may require amino acid-based formula (AAF) 1
• For infants with cow's milk-induced FPIES, introduction of soy formula should only be done under medical supervision (and vice versa) due to 20-40% co-reactivity risk in US patients 1

Maternal Diet During Breastfeeding

• Do not recommend routine maternal dietary elimination if the infant is thriving and asymptomatic 1
• Only eliminate trigger foods from maternal diet if:
  • Reactions occur after breastfeeding
  • Infant has failure to thrive
  • Nutritional consultation should be considered to assist with elimination diet 1

Management of Acute FPIES Episodes

Home Management

• For mild episodes (1-2 episodes of emesis with no/mild lethargy):

  • Attempt oral rehydration at home with breast milk or clear fluids
  • For children with history of severe reactions, seek emergency care even with mild symptoms 1

• For moderate-to-severe episodes (>3 episodes of emesis with moderate-to-severe lethargy):

  • Call 911 or go to emergency department immediately 1

Medical Facility Management

Based on severity of presentation:

1. Mild (1-2 episodes of emesis, no lethargy):

   • Oral rehydration
   • Consider ondansetron 0.15 mg/kg IM (max 16 mg) if ≥6 months old
   • Monitor for 4-6 hours from onset 1

2. Moderate (>3 episodes of emesis with mild lethargy):

   • Ondansetron 0.15 mg/kg IM (max 16 mg) if >6 months old
   • Consider IV line for normal saline bolus (20 mL/kg)
   • Transfer to ED/ICU if persistent hypotension, shock, lethargy, or respiratory distress 1

3. Severe (>3 episodes of emesis with severe lethargy, hypotonia, ashen/cyanotic appearance):

   • IV line with rapid normal saline bolus (20 mL/kg), repeat as needed
   • IV ondansetron 0.15 mg/kg (max 16 mg) if ≥6 months old
   • If IV access difficult, give ondansetron IM
   • Consider IV methylprednisolone 1 mg/kg (max 60-80 mg)
   • Monitor and correct acid-base and electrolyte abnormalities
   • Correct methemoglobinemia if present
   • Monitor vital signs
   • Discharge after 4-6 hours when stable and tolerating oral fluids 1

Ondansetron Use in FPIES

• Ondansetron (0.15 mg/kg, max 16 mg) is effective for stopping emesis during acute FPIES reactions 1, 3
• Use with caution in children with heart disease due to potential QT interval prolongation 1, 3
• Administration route:
  • IV preferred in emergency settings
  • IM if IV access is difficult
  • Oral can be considered for less severe cases 3

Long-term Follow-up and Monitoring

• Nutritional consultation is strongly recommended for all patients to ensure:

  • Adherence to dietary avoidance
  • Adequate nutrition despite restrictions 1

• Food challenges to assess for resolution should be performed:

  • In hospital setting with IV access for patients with history of severe FPIES
  • In physician's office for those without history of severe reactions
  • Under physician supervision when introducing potential cross-reactive foods 1

Prognosis

• Natural history of infantile FPIES is generally favorable, with most cases resolving by age 3-5 years
• Exception: fish FPIES in children and seafood FPIES in adults have lower resolution rates 2

Common Pitfalls and Caveats

• FPIES is frequently misdiagnosed as infectious gastroenteritis, sepsis, or other conditions 4
• No specific biomarkers exist for diagnosis; it relies on clinical recognition 2
• Testing for food-specific IgE is usually negative, though some patients (especially with cow's milk FPIES) may develop IgE sensitization over time, which tends to indicate a more prolonged course 5
• Brief resolved unexplained events (BRUE) may be confused with FPIES; key differentiating factors are presence of vomiting and duration >1 minute in FPIES 6

By following these guidelines, clinicians can effectively manage FPIES, minimize morbidity, and improve quality of life for affected patients.