Egg allergy. Diagnosis in immediate and delayed type allergy

Egg allergy is one of the most common food allergies in children. Common symptoms of egg protein-induced allergy frequently involve the skin as well as the gut, and in more severe cases lead to anaphylaxis. Non-IgE-mediated symptoms such as eosinophilic diseases of the digestive tract or egg-induced enterocolitis may also be encountered. Sensitization to egg white proteins can be encountered in young children in the absence of clinical symptoms. The egg allergy diagnosis is based on the suggestive clinical history, positive skin and/or serological tests and possibly the egg protein challenge test, the gold standard for confirming the diagnosis. Ovomucoid is identified as a major allergen contained in the egg white, and its identification allows to improve the diagnosis, to identify the patient who can tolerate the highly prepared thermally prepared egg, the patient with the risk of persistent egg allergy and with the risk of a severe reaction. Spontaneous remission and development of egg tolerance are common and occur in 60-75% of children before adolescence; however, the burden of disease is significant during childhood, making the early and accurate diagnosis a necessity.