Oral allergy syndrome. Literature review

Objective — to improve the methods of differential diagnosis and management of patients with oral allergy syndrome (OAS). 
Materials and methods. A literature review is presented and diagnostic approaches and principles of management of patients with OAS are analyzed. 
Results and discussion. OAS is a type of food allergy limited to the oral mucosa and triggered primarily by raw fruits, vegetables, flavorings, and nuts. Data on the prevalence of OAS vary considerably from study to study due to the use of different patient inclusion and exclusion criteria. However, there are reports of its frequency from 4.7 to more than 20 % in children and from 13 to 53.8 % in adults. It is reliably known that among the children’s population, OAS is mostly diagnosed in teenagers. Etiologically, OAS is caused by food allergens; mostly these are unprocessed fruits and raw vegetables that enter the patient’s oropharynx. Food allergens that cause OAS are actually inactivated by the gastric juice, so the reaction usually stops after the food is swallowed. 
Conclusions. OAS is a subtype of food allergy that can be found in the practice of allergists, dermatologists, general practitioners. After contact with food, patients experience the following symptoms: itching of the lips and oropharynx; paresthesia; angioedema of the mucous membrane of the oral cavity, tongue, palate and oropharynx; sometimes hoarseness is possible. Modern therapy of OAS involves the use of a complex approach, which includes adherence to an elimination diet, pharmacotherapy, and allergen-specific immunotherapy. Antihistamines, corticosteroids, and adrenaline (intramuscular) are most often used in pharmacotherapy.