Diagnosis and management
This section contains a background to Cow's Milk Allergy (CMA). It provides information on managing CMA by appropriate assessment and diagnosis according to relevant guidelines, and advice on when to use an amino acid-based formula for infants and children with CMA.
CMA Overview
CMA is a distressing condition for infants and their parents/carers:
- CMA is an immune mediated reaction to the proteins within cow's milk and is one of the most common food allergies affecting 2-5% of infants.1 Up to 40 000 babies a year in the UK may develop CMA.2
- Most cases of CMA present in infancy and the majority of children will grow out of the allergy by the age of 5 years.
- CMA can be complex to diagnose as many infants will often present with two or more symptoms frequently seen in infancy.
- The most common symptoms are of dermatological, gastrointestinal and respiratory origin.
Symptom complexity can delay diagnosis
Data from the UK shows:6
- It takes an average of 3.6 months from initial GP visit to formal diagnosis
Delayed diagnosis prolongs the distress for infants and their parents and has the potential to impact on infants' growth and development.
CMA imposes a substantial burden on the NHS
Patients with CMA had a mean of 18.2 clinician visits and cost the NHS an estimated £25.6 million during the first 12 months after initial presentation:6
The initial aim of management is prompt and accurate diagnosis, removal of cow's milk protein from the diet whilst ensuring the nutritional requirements of the infant/child are met using suitable specialist formulas and dietary modification.
CMA assessment
NICE have produced a guideline (CG 116) to aid in the diagnosis and assessment of food allergy in children and young adults. The first steps are initial recognition, an assessment of the symptoms and the allergy focused history. The guideline includes a series of algorithms, which have been reproduced with the permission of NICE for use on this website.
Diagnosis
CMA can be classified according to whether the allergic reaction is an IgE mediated (within 2 hours) or a non IgE mediated (delayed, chronic) response. The NICE guideline helps determine the type of allergy and outlines the tests that should be used to confirm the diagnosis.
Once an allergy is suspected NICE recommends that an elimination diet should be tried for 2 to 6 weeks. The allergen should then be reintroduced to confirm diagnosis. NICE also recommends that the advice of a dietitian with appropriate competencies should be sought to assist with nutritional adequacies, timings of elimination and reintroduction, and follow-up.
The algorithms found below have been reproduced with the permission of NICE.
Once the diagnosis of the CMA has been confirmed, including the type of allergy (IgE or non IgE), a management plan can be established.
Management
CMA is managed by excluding cow's milk protein from the diet.
Breast feeding is always the preferred way to feed an infant. If an infant is being breast fed, the mother needs to follow an exclusion diet with the support of the dietitian to ensure that the maternal diet is adequate. Calcium and Vitamin D supplements are recommended.
Formula fed infants will need to be provided with a replacement hypoallergenic formula, either an extensively hydrolysed or amino acid formula.
There are specific times where the use of an amino acid formula is indicated.