Although egg allergy can develop in adult life, this is nearly always a condition that develops in infancy or early childhood.
In Europe and elsewhere a significant proportion of the population report adverse reactions to food which they regard as ‘allergy’, but generally few of these perceived reactions are true IgE-mediated reactions. A recent analysis of the prevalence of sensitisation to 24 foods, among a random sample of over 4500 young adults in 13 countries, found overall rates to be highly variable across different countries. However, sensitisation rates to specific foods were similar in all countries. Sensitisation rates to egg were generally low at an average of 0.2% in the overall sample population; the figure for the UK was 0.5%1.
Adult allergy symptoms
The symptoms in an egg allergic reaction in an adult can be similar to those seen in childhood, but particularly include angioedema (skin swelling) or eczema and asthma, which can develop more gradually.
If there is a strong suggestion of a reaction to food, but the cause is not clear, a negative skin or blood test in an NHS Allergy Clinic may help to exclude egg as a cause of symptoms. Challenge tests with egg or with other foods may sometimes be advised.
In patients with suspected non-IgE mediated reaction to egg there is currently no reliable test to confirm the diagnosis. Thus a trial of an egg free diet followed by controlled challenge is the only strategy for management.
1 Burney P, Summers C, Chinn S, Hooper R, van Ree R, Lidholm J (2010) Prevalence and distribution of sensitization to foods in the European Community Respiratory Health Survey: a EuroPrevall analysis, Allergy 2010; 65, 1182-1188