What is the management and treatment for a patient with a cow milk protein allergy?

Management and Treatment of Cow's Milk Protein Allergy

Complete elimination of cow's milk protein is the cornerstone of CMPA management, with extensively hydrolyzed formula (eHF) as the first-line treatment for formula-fed infants and maternal elimination diet for breastfed infants. 1

Diagnostic Approach

CMPA presents in two main forms:

• IgE-mediated: Rapid onset (minutes to 2 hours) with symptoms like urticaria, angioedema, vomiting, and respiratory symptoms
• Non-IgE-mediated: Delayed onset (2-72 hours) with symptoms like persistent diarrhea, blood in stool, and failure to thrive 1

Diagnosis requires:

1. Structured elimination diet (2-4 weeks for IgE-mediated, 2-6 weeks for non-IgE-mediated)
2. Challenge testing for confirmation
3. Skin prick tests and serum-specific IgE testing may help in IgE-mediated cases 1

Treatment Algorithm

For Breastfed Infants:

• Continue breastfeeding with maternal elimination of all dairy products for 2-4 weeks 1
• Maternal diet should restrict at least milk and egg 2
• Provide calcium and vitamin D supplements for the mother 1
• Monitor infant's growth and symptom improvement 1

For Formula-Fed Infants:

1. First-line: Extensively hydrolyzed formula (eHF) - tolerated by >90% of children with CMPA 1
2. Second-line/Severe cases: Amino acid formula (AAF) if symptoms persist despite eHF 1
3. Alternative options:
   • Soy formula may be considered in infants >6 months (10-15% cross-reactivity) 3
   • Rice hydrolysates are emerging alternatives with better taste and lower cost 3

For Acute Reactions:

• Antihistamines for mild-moderate reactions
• Epinephrine auto-injector for severe reactions with proper training on use 1

Follow-up and Monitoring

• Review within 2-4 weeks after starting elimination diet
• Regular monitoring of growth parameters
• Reassess for tolerance development:
  • Every 6-12 months for children under 2 years
  • Every 12-18 months for older children 1
• Consider oral food challenge at 9-12 months to assess tolerance development 1

Prognosis and Resolution

• CMPA typically resolves during the first 2-3 years of life 1
• Studies show recovery rates of:
  • 45-56% at one year
  • 60-77% at two years
  • 71-87% at three years 4
• IgE-mediated CMPA tends to be more persistent than non-IgE-mediated 1

Gradual Reintroduction

• A milk ladder approach (gradual introduction of milk-containing foods) is recommended when reintroducing milk
• Recent evidence shows that a supervised single low-dose exposure to cow's milk at diagnosis may accelerate progress on a milk ladder program 5

Common Pitfalls to Avoid

• Overdiagnosis leading to unnecessary dietary restrictions
• Inappropriate formula choice
• Inadequate parent education
• Delayed diagnosis
• Failure to monitor growth and nutritional status 1

Indications for Specialist Referral

• Anaphylaxis
• Failure to thrive
• Multiple food allergies
• Significant feeding difficulties
• Persistent symptoms despite appropriate elimination diet
• Diagnostic uncertainty 1

Remember that CMPA is often self-limiting, but proper management is essential to ensure adequate nutrition and growth while avoiding unnecessary restrictions.