What are the next steps for an infant who still shows no improvement after cow's milk (lactose) elimination?

Management of Infants with Persistent Symptoms After Cow's Milk Elimination

For infants who show no improvement after cow's milk elimination, the next step should be to consider alternative food allergies, evaluate for other non-allergic conditions, and potentially transition to an extensively hydrolyzed or amino acid-based formula.

Diagnostic Considerations

• Consider that multiple food allergies may be present - up to one-third of infants with cow's milk protein allergy may also react to soy protein 1
• Evaluate for Food Protein-Induced Enterocolitis Syndrome (FPIES), which can present with repetitive vomiting, lethargy, pallor, and diarrhea within 1-4 hours of food ingestion 1
• Assess for Food Protein-Induced Allergic Proctocolitis (AP), which manifests as blood-streaked stools in an otherwise healthy infant 1
• Consider eosinophilic esophagitis (EoE), which may require endoscopy with biopsy for diagnosis if symptoms persist 1

Next Steps in Management

1. Formula Modification

• Switch to an extensively hydrolyzed protein formula as the first alternative 1, 2
• If no improvement occurs with extensively hydrolyzed formula, progress to amino acid-based (elemental) formula 1
• Amino acid-based formulas have shown a higher histological response rate (90.8%) compared to allergy-test directed diets (45.5%) 1

2. For Breastfed Infants

• Extend maternal elimination diet beyond cow's milk to include additional common allergens such as egg, wheat, soy, peanuts/tree nuts 1, 2
• A 2-4 week trial period is recommended for each elimination to properly assess response 1
• Monitor maternal nutrition and consider supplements if multiple foods are eliminated 1

3. Consider Additional Testing

• Upper endoscopy with esophageal biopsy is indicated in infants with poor weight gain who fail to respond to initial dietary changes 2
• Stool examination for blood, leukocytes, or eosinophils may help identify allergic proctocolitis 1
• Colonoscopy and biopsy may be considered as an alternative diagnostic approach in patients with only gastrointestinal manifestations 3

4. Feeding Techniques

• Reduce feeding volume while increasing feeding frequency to minimize gastric distension 1, 2
• Implement proper burping techniques after feedings 2
• Keep the infant in a completely upright position when awake 1, 2

Management Algorithm

1. First attempt: Cow's milk protein elimination (2-4 weeks)
2. If no improvement:
   • For formula-fed infants: Switch to extensively hydrolyzed formula
   • For breastfed infants: Extend maternal elimination diet to include egg
3. If still no improvement after 2 weeks:
   • Formula-fed: Progress to amino acid-based formula
   • Breastfed: Further extend maternal diet to eliminate wheat and soy
4. If symptoms persist:
   • Refer to pediatric gastroenterology
   • Consider endoscopic evaluation
   • Evaluate for non-allergic causes of symptoms

Common Pitfalls to Avoid

• Failing to allow adequate time (2-4 weeks) for clinical response to dietary changes 1, 2
• Not recognizing that milk protein allergy can mimic or exacerbate GERD symptoms 1, 2
• Overlooking the possibility of multiple food allergies - a significant number of infants with cow's milk allergy may also react to soy 1
• Starting pharmacologic therapy (such as acid suppressants) before fully exploring dietary management options 1, 2
• Missing warning signs that require immediate evaluation such as bilious vomiting, gastrointestinal bleeding, consistently forceful vomiting, fever, or abdominal distension 2