Egg allergy in infants and children
The frequency of all food hypersensitivity is at a peak in the first year of life. Egg allergy is most common in infants under the age of twelve months and then becomes progressively less of a problem. Few children are allergic to egg after the age of six, 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.
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.
Although there are some food allergies that tend to be life-long – such as allergy to peanuts –allergies to eggs usually diminish and disappear after a period of time in children. In mild cases and if egg is successfully avoided there may be improvement within months and by the age of six or seven the large majority of children need no restriction in their egg consumption. A recent analysis* of the prevalence of sensitisation to foods in the European Community found that only 0.2% of adults in the UK are sensitive to eggs.
There are, however, some precautions that need to be taken.
- In severe cases it will also be important to have advice about treatment that might be needed in an emergency.
- The help of a 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 added to 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 advice will be needed after a symptom-free period, so that the careful reintroduction of eggs can be considered, but only with medical support.
*Burney P, Summers C, Chinn S, Hooper R, van Ree R, Lidholm J, Prevalence and distribution of sensitization to foods in the European Community Respiratory Health Survey: a EuroPrevall analysis, European Journal of Allergy and Clinical Immunology, 10:1111, p.1398-9995