Cows milk Protein Allergy

Question 1

What is the relevant epidemiology of cows milk protein allergy?

Answer 1

Most commonly in infants
33 per 100,000 person years

Question 2

What are the different classifications of cows milk protein reactions?

Answer 2

Immediate - IgE mediated - considered an allergy
Delayed - non-IgE mediated - considered an intolerance

Question 3

What is the typical GIT presentation of CMPI?

Answer 3

Delayed onset 48hrs after an ingestions ->
Diarrhoea (chronic, may have blood/mucus), vomiting, failure to thrive and abdominal discomfort -> typically after cows milk into their diet
Eczema not responding to treatment, urticarial rash, asthma like symptoms not responding.

Question 4

What is the key presentation of a cows milk protein allergy?

Answer 4

IgE mediated within 2hrs of ingestions
Urticaria, angioedema, vomiting and wheezing.

Question 5

What are the first line investigations for a cows milk protein allergy?

Answer 5

Note clinical diagnosis
Dietary elimination and reintroduction associated with symptoms
Skin prick test - for IgE mediated CMA
Specific IgE testing - higher level suggests inc likelihood of diagnosis

Question 6

What second line investigations may be used for cows milk protein intolerance/allergy?

Answer 6

Dietary elimination with amino acid based formula - removes all possible protein as broken down
Faecal calprotecting -> for non-IgE
Endoscopy with biopsy -> supportive not diagnostic

Question 7

What is the management of cows milk protein allergy in formula-fed infants?

Answer 7

Extensive hydrolysed formular milk if mild to mod
Amino acid based formular in severe or no response to above
Rule out soya milk as 10% also intolerant

Question 8

What is the management for CMPA in a breast fed infant?

Answer 8

Continue breastfeeding
Eliminate cows milk protein from maternal diet - may need calcium supplements
Use eHF milk when breastfeeding stops until 12m of age for 6m+

Question 9

What is the typical prognosis of CMPA in infants?

Answer 9

In children with IgE mediated - around 55% will be milk tolerant by age 5yrs
non-IgE mediated - tolerant by 3yrs
Challenge in hospital setting in case of anaphylaxis.

Question 10

What are the typical signs of an IgE mediated cows milk protein allergy?

Answer 10

Urticaria, angio-oedema, itch cough, hoarseness, wheeze, breathlessness
Severe, persistent and multiple system.

Question 11

What are the pathoplogical process in cows milk protein intolerance and allergy?

Answer 11

Allergy - type 1 hypersensitivity
Intolerance - type 4 hypersensitivity