Urticaria, eczema, wheeze, colic and reflux may all be caused by an allergy to cow’s milk, said Dr Ian Mercow, consultant paediatrician at Stockport NHS Trust and a member of the Act Against Allergy group.
‘About 10 to 20 per cent of patients with reflux symptoms or colic have allergies to cow’s milk, and it is more common in infants with symptoms of atopic dermatitis,’ he said.
A family history of allergy and a record of poor weight gain make an allergy to cow’s milk more likely. Symptoms often start when infants are moved from breast feeding to formula, but allergies to cow’s milk could occur in wholly breast-fed infants if allergenic peptides from cow’s milk in the maternal diet are present in breast milk.
GPs and paediatricians should investigate the possibility of the allergy or ‘parents will turn to unvalidated alternative medicine’, said Dr Mercow.
In young infants, a two-week trial of a hypoallergenic formula, such as one that is extensively hydrolysed or amino acid-based could establish whether a patient has a cow’s milk allergy, he said.
‘If the symptoms disappear, allergy to cow’s milk protein is likely to be the cause,’ added Dr Mercow.
‘I am not suggesting all infants with these symptoms should be put on a trial of hydrolysed formula, but it can be useful when there is a high index of suspicion that it is allergy to cow’s milk.’
Dr Richard Stevens, Oxford GP and chairman of the Primary Care Gastroenterology Society, was ‘cautious about endorsing a change to standard treatment’. However, he said it might be ‘worth trying’ a formula free from cow’s milk protein, provided it was safe.
What to consider
When to suspect cow’s milk allergy in infants:
Angiooedema.
Atopic dermatitis, urticaria.
Wheeze.
Colic.
Vomiting and diarrhoea.
Bloody ‘coffee grain’ stools.
Failure to thrive.
Family history of atopy.