Jun 183 min read

Cow's Milk Protein Allergy (CMPA): Diagnosis and Management

Cow's milk protein allergy is the most common allergy affecting infants however despite this many healthcare professionals can be late to diagnose this leaving parents to struggle and reaching to friends, family and the internet as a source of information. Luckily if you are reading this blog you are in the right place for up to date information hopefully empowering you at whatever step you are in your allergy journey.

#1 Symptoms of CMPA

Symptoms of CMPA can vary from mild to severe and may affect multiple body systems as outlined below:

Gastrointestinal issues: Diarrhoea, constipation, mucous in stools, blood in stools, vomiting, reflux, and colic.

Skin reactions: Eczema, hives, and rashes.

Respiratory problems: Wheezing, coughing, and nasal congestion.

General symptoms: Irritability and poor weight gain.

These symptoms can appear within minutes or hours after consuming cow's milk protein or can be delayed, emerging days later.

#2 Diagnosis

CMPA can be classed as either IgE-mediated or non IgE-mediated allergy according to how quickly the symptoms occur after ingestion of cow's milk protein. IgE allergies are thought to present as more 'immediate' reactions (within 2 hours) whereas the most common presentation is non IgE mediated 'delayed' reactions presenting often hours later.

Diagnosis is normally made following an allergy-focused history taking including full review of the child's symptoms, family history of atopy (food allergy, hayfever, asthma, eczema) as well as feeding history. IgE allergies can be tested for with blood tests and skin prick testing (normally in a skilled allergy clinic); whereas non- IgE allergy will not show up in this way, and would need elimination of the offending allergen (milk) from the diet (of mum if breastfeeding) or the formula if formula feeding.

The most recent ESPGHAN guidelines reiterate the importance of confirming CMPA by the reintroduction of cow's milk protein back into babys diet either as breastmilk or formula and seeing if symptoms recur. Very severe CMPA reactions including Anaphylaxis howevere do not require rechallenging as this would be risky for baby.

#3 - How long to eliminate cow's milk protein for?

Breastfed infants: remove milk from Mum's diet for 2-4 weeks. Ensure mum has adequate calcium in her diet (fortified plant-based alternatives plus calcium supplement ~500mg/d)

Mild-moderate CMPA

Formula-fed infants: change to extensively hydrolysed formula (prescribed) for 2-4 weeks

Severe symptoms or anaphylaxis

Change to an amino acid formula

#4 Rechallenge

Breastfed infants: Mum to reintroduce Cow's milk back into her diet - if symptoms return confirmed diagnosis of CMPA. To revert back to being milk-free with adequate maternal calcium intake (aim 1250mg a day from diet and supplements)
Formula-fed infants: the method most parents feel happiest with is swapping out an ounce of allergy formula for normal formula per feed until they are fully graded over to their usual cow's milk protein containing formula. This can take a couple of days depending. If symptoms return the CMPA diagnosis is confirmed and feeding should revert back to the allergy formula.

#5 Living with CMPA

Managing CMPA requires vigilance, but it’s entirely manageable with the right strategies.

Education: Educate yourself and anyone involved in your child’s care about CMPA and the importance of avoiding cow's milk proteins. Speak to a paediatric dietitian with experience in allergy for advice on milk-free weaning and ensuring nutritional adequacy of the diet.

Planning: Plan meals and snacks ahead of time to ensure they are free of cow's milk protein.

Support: Connect with support groups and resources for families dealing with food allergies.