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GETTY IMAGES combination with breastmilk ) will require a prescribed hypoallergenic formula . An extensively hydrolysed formula ( eHF ) will be suitable for most children . However , for those who have severe symptoms of allergy ( such as anaphylaxis ), or where there is no improvement with an eHF , an amino acid formula ( AAF ) should be tried . Follow local guidelines on choice of brand . Parents may wish to buy their own alternative milk , but this is not wise . Children with CMPA are often also allergic to other mammalian milks , such as goat and sheep , as well as soy milk . Soy milk provides insufficient nutrients and also has a weak oestrogenic effect that could theoretically affect the reproductive system . 3 , 4 Milks such as almond , oat and coconut have poor nutritional value , while rice milk has a natural arsenic content that makes it unsuitable for use below the age of five . 1
For babies who are breastfed ( exclusively or in combination with formula ), the mother should exclude all cow ’ s milk products from her own diet . This is not always easy and she should be offered dietitian support and a calcium supplement . If the child ’ s symptoms improve with milk exclusion then it is crucial to reintroduce the milk and monitor to see if symptoms recur . This is not always popular with parents , as no one wants to deliberately make their child unwell , but if it isn ’ t done we risk overdiagnosis , as symptoms may have coincidentally improved when milk was excluded . CMPA is much less common in exclusively breastfed infants , with one study of 1,749 infants identifying 39 with CMPA , of whom only nine were exclusively breastfed . 5
Ongoing management Follow-up In most areas , rules on medicines management indicate that ongoing provision of hypoallergenic formula needs to be accompanied by a referral to paediatrics . Whether or not this is the case , the child should be kept on a cow ’ s milk-free diet for at least six months , and as a minimum until they are nine to 12 months old , at which point there can be a gradual , supervised reintroduction of cow ’ s milk . This should be done in hospital if there was anaphylaxis , but otherwise can be done at home using the milk ladder to guide reintroduction . Referral to paediatrics may be done as well as , or instead of , referral to dietetics , depending on local pathways .
Be mindful of overdiagnosis concerns Parents who have done background reading or discussed their child ’ s CMPA online might ask if you are aware of overdiagnosis of the allergy . This has received increased attention since a 2018 report , which included criticism of the iMAP guidance . 6
It is reasonable to query a sudden increase in any diagnosis or treatment over a short period of time . Much of the concern has come from the observation that UK prescriptions for hypoallergenic formula increased markedly ( by 500 % between 2006 and 2016 ), without anything to suggest a true increase in allergy . However , closer scrutiny reveals a more complicated picture . The steep increase in formula prescriptions actually began in 2003 , 10 years before the first iMAP guidance was published in 2013 and four years before there was any written guidance on CMPA in the UK . Moreover , a key confounder here is that soy-based formulas were widely used in the UK until 2003 , when guidance was issued advising against them ( for the reasons discussed above ). 3 , 4 Prescriptions for soy-based formula fell steeply from 2003 , the same point at which prescriptions for hypoallergenic formula started to increase , suggesting
Non-IgE-mediated allergy is more complicated . The immune process is less clear cut and there are no diagnostic tests
References 1 NICE CKS . Cow ’ s milk allergy in children . 2021 . bit . ly / 41ODIFF 2 Fox A , Brown T , Walsh J et al . An update to the Milk Allergy in Primary Care guideline . Clin Transl Allergy . 2019 Aug 12 ; 9:40 . 3 Tuohy PG . Soy infant formula and phytoestrogens . J Paediatr Child Health . 2003 Aug ; 39 ( 6 ): 401-5 4 Committee on toxicity of chemicals in food , consumer products and the environment . Statement on the potential risks from high levels of soya phytoestrogens in the infant diet . 2003 . bit . ly / 3L1L1Ug 5 Høst A , Husby S , Osterballe O . A prospective study of cow ’ s milk allergy in exclusively breast-fed infants . Incidence , pathogenetic role of early inadvertent exposure to cow ’ s milk formula , and characterization of bovine milk protein in human milk . Acta Paediatr Scand . 1988 Sep ; 77 ( 5 ): 663-70 . 6 Van Tulleken C . Overdiagnosis and industry influence : how cow ’ s milk protein allergy is extending the reach of infant formula manufacturers . BMJ 2018 ; 363 : k5065 7 Sunshine UK . A register of doctors ’ declared interests . whopaysthisdoctor . org 8 UNICEF . Breastfeeding : a public health issue . bit . ly / 2PRGPup 9 Australian Family Physician . A is for aphorism – is it true that ‘ a careful history will lead to the diagnosis 80 % of the time ’? 2012 . bit . ly / 3yeiinQ some infants would have been switched from one to the other . It is also possible that wider recognition of non-IgE-mediated CMPA contributed to the increase .
Another criticism of the guidelines has been use of non-specific symptoms . As any parent knows , children ’ s bowels seem to have a mind of their own . The contents of nappies changes from time to time . Likewise , infants ’ burping , vomiting and colic can come and go for no obvious reason . There is clearly a risk that such normal variation could be mistaken for allergy and lead to overdiagnosis . However , the iMAP guidance has always advocated reintroduction of cow ’ s milk , so an improvement in symptoms when milk is removed and a worsening when it is reintroduced is needed for diagnosis . Provided this is carefully followed , we should avoid overdiagnosis due to a coincidental change in symptoms .
While the formula industry has come under some legitimate criticism for promotional tactics , specific concerns about undue influence on the iMAP guidelines seem to be clouded by misconceptions . For example , the iMAP flowcharts have always been open access , with the unintended consequence that some formula manufacturers have used them in promotional material . While the iMAP authors have declared research grants or consultancy fees from the makers of formula milk , this is common under current funding systems ; many doctors who write , present and conduct research inevitably receive at least some industry funding for their work . 7
It should be noted that the 2019 iMAP update included unfunded input from parent and professional groups with no industry ties .
Breastfeeding support Concerns have also been raised around a reduction in breastfeeding rates , but this likely relates to wider issues around a lack of breastfeeding support . It is unusual for me to see a woman who is fully breastfeeding at the time of her six-week check and this is backed up by statistics – 81 % of women give their baby some breastmilk after birth but only 24 % are exclusively breastfeeding at six weeks , with this figure dropping to 1 % at six months with 34 % giving some milk at this point . 8
In the absence of any political will to , for example , adequately fund a network of accessible lactation advisors or to ensure all women have access to decent paid parental leave and support , it ’ s easy to blame this on guidelines that recommend breastfeeding women cut out dairy ( which is difficult and may lead women to stop breastfeeding if not properly supported ). The 2019 iMAP guideline does advise that exclusive breastfeeding until six months is a good thing , and recommends active support . Symptomatic CMPA is less common in infants who are exclusively breastfed than those given formula , but it is possible , so it is important that we provide quality information and support to this group of women , and that we are able to make a diagnosis if appropriate , while the woman continues to breastfeed .
I was always taught that 80 % of a diagnosis comes from the history 9 and that medicine is an art not a science . We are used to backing up initial impressions with tests , but where this isn ’ t possible ( such as with non-IgE-mediated CMPA ), doctors and nurses in primary care should be comfortable relying on clinical skills and our ‘ spidey sense ’ that something is wrong . If you listen , consider possible differentials , seek help if you need it and always re-challenge to confirm a non-IgE-mediated CMPA diagnosis , your patients will be in good hands .
Dr Toni Hazell is a GP in north London