Cow's milk protein intolerance/allergy

Cow's milk protein intolerance/allergy (CMPI/CMPA) occurs in around 3-6% of all children and typically presents in the first 3 months of life in formula-fed infants, although rarely it is seen in exclusively breastfed infants.

Both immediate (IgE mediated) and delayed (non-IgE mediated) reactions are seen. The term CMPA is usually used for immediate reactions and CMPI for mild-moderate delayed reactions.

Features

• regurgitation and vomiting
• diarrhoea
• urticaria, atopic eczema
• 'colic' symptoms: irritability, crying
• wheeze, chronic cough
• rarely angioedema and anaphylaxis may occur

Diagnosis is often clinical (e.g. improvement with cow's milk protein elimination). Investigations include:

• skin prick/patch testing
• total IgE and specific IgE (RAST) for cow's milk protein

Management

If the symptoms are severe (e.g. failure to thrive) refer to a paediatrician.

Management if formula-fed

• Extensively Hydrolysed Formula (eHF): This is the first-line option for infants with mild to moderate symptoms. eHF contains proteins that are broken down into smaller peptides, which reduces allergenicity while maintaining adequate nutrition. Common brands include Alimentum and Nutramigen.
• Amino Acid-Based Formula (AAF): Indicated for infants with severe CMPA or those who do not respond to eHF. AAF is composed of free amino acids, eliminating the risk of allergic reactions. Examples include Neocate and Elecare. These formulas are typically more expensive and may be used in cases of failure to thrive or severe gastrointestinal symptoms.
• Soya Milk Intolerance: Approximately 10% of infants with CMPA may also exhibit intolerance to soya-based formulas. Therefore, caution should be exercised when considering soya as an alternative, especially in infants under six months due to potential phytoestrogen effects.