What is an egg allergy and its Symptoms?

What is an egg allergy and its Symptoms?


Egg allergy is the most common cause of food allergy in children one to two years of age, although it usually disappears within the first six years of life. Learn to identify and prevent it.

The eggs of birds, especially those of chickens, are food commonly present in humans’ diets since they contain proteins of high value for the formation of muscles and tissues. However, egg allergy is the most common cause of food allergy in children one to two years of age, although it usually disappears within the first six years of life.

As in any case of allergy, in egg allergy, the body produces an antibody, immunoglobulin E (IgE), which acts against the egg allergen. The union between the allergen and IgE triggers the allergic reaction, with symptoms such as hives, diarrhea, asthma, sleep disturbance, manifestations of atopic dermatitis, nausea, vomiting, and anaphylaxis.

The allergy occurs mainly when ingesting the white because it is the one that contains the significant allergens, which are:

  • Ovalbumin (54% of its composition).
  • Ovotransferrin or conalbumin (12%).
  • Ovomucoid (11%).
  • Lysozyme (3.5%).
  • Ovomucin (1.5%).

Symptoms appear when the affected person ingests eggs and allergens such as ovalbumin, ovotransferrin, ovomucoid, ovomucin, and lysozyme come into contact with the body. Ovalbumin is the most abundant protein, but the most allergenic is ovomucoid. Yolk livetins are implicated in the most common allergy in adulthood.

Egg allergy epidemiology

The prevalence of egg allergy in the child population is estimated to be between 1% and 3% and decreases as the child grows. The age of presentation of the allergy is usually during the first two years of life, especially between six and 12 months, and has a good prognosis since the food can be better tolerated later. Later-onset allergies, by contrast, can last a lifetime.

Symptoms of egg allergy

In most cases of egg allergy, symptoms begin less than 60 seconds after ingestion of this food. Both the white and the yolk can cause this reaction, so it is important not to eat the foods that include it in their composition. The most common egg allergy symptoms are:

  • Skin manifestations, such as hives, cause an itchy sensation that can cause skin damage.
  • Atopic dermatitis (AD) may be related to egg allergens, although the time between the onset of the condition and the intake of this food has not been determined. Also, in children with this problem, the consumption of eggs can increase atopic dermatitis.
  • Gastrointestinal symptoms, such as contact urticaria in the oropharynx, cause itching and angioedema of the lips, tongue, palate, and throat. Nausea, vomiting, abdominal discomfort, and diarrhea can also occur.
  • Respiratory symptoms include asthma, bronchial hyperresponsiveness, and rhinoconjunctivitis (itchy and stuffy nose, watery eyes, and sneezing).

The allergic reaction can also cause hypotension and arrhythmias. If this reaction affects several organs at the same time, it can cause severe anaphylactic shock.

It is essential to know that in some cases, you can have an allergy to some of the parts of the egg or even tolerate its digestion but that hives may occur as a result of contact with food. Therefore, if you notice some of these symptoms after ingesting eggs, you should see a doctor.

Diagnosis of egg allergy

The intervention in the nutrition of patients with allergies is aimed at identifying the allergenic food and the orientation and nutritional management of the food allergy detected, in this case to eggs.

To identify the allergenic food, the specialist must carry out a food anamnesis, various questions about the patient’s health status, and skin tests, such as the prick test. Also, they make serological tests (specific IgE in the blood), an exposure test, which is that the patient ingests food suspected causes reaction, and then set up an elimination diet.

The doctor’s anamnesis must be exhaustive and include data on the food eaten, both regularly and sporadically, remembering that symptoms can occur from the moment of ingestion until even a few days later.

It is essential to know and even ask if the baby had any symptoms of egg allergy during breastfeeding since the child can become sensitized and manifest symptoms due to exposure to egg proteins present in the foods eaten by the mother and that are they are transferred to you through breast milk.

Elimination diets follow criteria based on clinical observation of the changes that occur when the allergen is suppressed and reintroduced into the patient’s diet.