An assessment of the frequency of symptoms that guidelines associate with non-IgE mediated cow’s milk allergy: a secondary analysis of the Enquiring About Tolerance (EAT) Study.
The Milk Allergy in Primary Care (MAP) Guideline, updated in 2019 (international MAP), was developed to help identify infants with cow’s milk allergy. However, concerns have been expressed that such guidelines may misattribute normal symptoms and contribute to over-diagnosis of this condition, resulting in the unnecessary prescription of specialized infant formula milks and potentially discourage breastfeeding. We sought to establish the frequency of symptoms associated with CMA in the 2019 iMAP guideline; and compare symptom frequency in infants with and without eczema.
We undertook secondary analysis of data from the Enquiring About Tolerance (EAT) randomised controlled trial, including 1303 breastfed infants, and performed subgroup analysis of infants with visible eczema at three months. A consensus approach was used to map EAT data collected to the iMAP listed symptoms.
The mean monthly proportion of infants with two or more of the mild-moderate non-IgE mediated CMA symptoms was 25.3% over the first 3-12-months of life. The peak figure (37.6%) occurred when infants had two or more different symptoms at three months of age – at this point no children were consuming cow’s milk directly. The percentage reduced with age, with 14.4% of infants reported to have two or more symptoms at 11 months. When the symptoms ‘pruritus’ and ‘eczema’ were excluded, a mean of 17.9% of infants with eczema had two or more symptoms each month, compared 18.5% of those without. At six months, there was no difference in the number or severity of symptoms between participants consuming or not consuming cow’s milk.
Symptoms listed in the iMAP guideline are very common in infants. Non-eczema symptoms are no more frequent among infants with eczema. Guidelines such iMAP this may promote overdiagnosis of CMA, and unnecessary cow’s milk protein exclusion from maternal and infant diets.