Nutrition and Eggs
Egg allergy in infants and children
egg allergy in infants and children
The frequency of all food hypersensitivity is at a peak in the first year of life.
Estimates of prevalence of food allergies are frequently based on self-reported data and therefore may overstate the issue. A 2007 meta-analysis included both self-reported and more objectiv evidence of IgE-mediated reactions, such as skin prick and double-blind challenged data.* The reported prevalence for egg allergy in young children based on symptomatic and skin prick/IgE tests in this analysis was 0.5% - 2.5%.
It has been observed that more than half of the infants who develop egg allergy begin to have symptoms within minutes of being given an egg for the first time. While it is possible that some have received small amounts of egg in a manufactured baby food, it is also possible that some have actually been sensitized before birth or via breast milk.
In infants and small children the development of an egg allergy can be dramatic. The most common immediate way in which this allergy presents itself is with a red rash around the mouth within seconds of eating an egg, followed in a few minutes by angioedema - swelling around the mouth, on the face and also inside the mouth. A few babies develop vomiting, but diarrhoea is relatively uncommon. In severe cases anaphylaxis may occur. Later, further areas of angioedema or eczema can occur, together with respiratory involvement (sneezing and wheezing), or running of the eyes. If there has been local skin swelling on contact with egg (especially raw egg) this is very strongly suggestive of egg allergy. Children who have this problem will often refuse egg when it is offered to them.
Egg allergy is most common in infants under the age of twelve months but at least 50% of children will outgrow this by school age, though in some cases this allergy can persist to adult life. Those with other allergies or with a family history of allergy seem to be particularly vulnerable to persistent egg allergy.
This phenomenon of tolerance among children with food allergies is well-recognised. Therefore, although some food allergies tend to be life-long – such as allergy to peanuts – allergies to eggs frequently diminish and disappear after a period of time in children. A recent US study of over 2,000 cases of food allergy suggested that 28% had developed tolerance by the age of ten and that children most commonly developed tolerance to eggs.**Therefore in some cases and if egg is successfully avoided there may be improvement within months and by the age of six or seven many children need no restriction in their egg consumption.
There are, however, some precautions that need to be taken.
- In severe cases where there is a risk of anaphylaxis it will also be important to have advice about treatment that might be needed in an emergency.
- The help of a Registered Dietitian will be needed if all egg-containing foods are to be avoided. The use of eggs in cakes, custard, mayonnaise and some pasta is well known; their use in bread, in the glazes on buns or pies, and in some confectionery may not be so obvious.
- It is advisable to keep a record of any occasions when an egg-containing food is eaten by mistake and of any symptoms that may follow, so that a judgment can be made as to whether the symptoms are diminishing.
- In milder cases, after a symptom-free period, the careful reintroduction of eggs may be considered, but this should only be carried out with medical support.
*Rona RJ, Keil T, Summers C et al (2007) The prevalence of food allergy: A meta-analysis. Journal of Allergy and Clinical Immunology, 120:638-646
**Gupta R, Lau CH, Springston EE et al (2012) Childhood food allergy tolerance and associated factors (Abstract FP18) Annals of Allergy, Asthma and immunology, 109,Supplement A1-A162