Oral allergy syndrome in children

Abstract

Oral allergy syndrome (OAS) is an allergic reaction that occurs after consumption of fresh fruits and vegetables in patients with allergy to pollen. It is mediated by immunoglobulin E (IgE) antibodies and symptoms arise as a result of cross-reactivity between pollen and plant-derived food. OAS is rarely seen in young children, but the prevalence increases with age. The objectives of the study were to identify the prevalence of OAS and probable risk factors in children and adolescents with seasonal allergic rhinitis (AR). One-hundred and twenty patients with seasonal AR were included. Patients were diagnosed based on their clinical history, skin prick test outcome and specific IgE. In patients describing OAS, prick-by-prick tests with fresh fruit or vegetables were carried out. Thirty-two patients had OAS and it was more frequent in female patients than in male patients. OAS was more frequent in adolescents than in small children and in patients with higher total IgE. OAS was significantly more prevalent in patients with AR and asthma (P=0.0016), as was the case in patients with AR and atopic dermatitis (P=0.0004). OAS is rarely diagnosed in small children, partly because of an inadequate clinical history. Patients with OAS may have some risk factors in addition to pollen allergy, and those with more severe atopy are more likely to develop OAS.

Patterns of sensitization to inhalant and food allergens among pediatric patients from the Moscow region (Russian Federation)

“…Age-related changes in the occurrence of sensitization to allergens in various groups of children in the Moscow region ( Fig 3 ) correspond to trends that are observed in populations from other countries of the world [ 41 ], where the occurrence of sensitization to inhalant allergens increases with the age of the patients, whereas the number of patients who have sensitization to food allergens decreases with age. One exception, according to the data presented in Fig 3 , is apples and carrots, which may show growth in sensitization associated with the birch pollen allergen [ 42 ].…”

Food allergy: immune mechanisms, diagnosis and immunotherapy

“…Variants of IgE-mediated food allergy include oral allergy syndrome (OAS), in which individuals with allergic rhinitis produce IgE molecules specific for pollen-derived epitopes that are crossreactive with fruit- or vegetable-protein epitopes 22 . Signs and symptoms of OAS include immediate oral pruritus, mucosal angioedema and/or abdominal pain.…”

Diagnosis of Food Allergy

“…OAS results from IgE sensitization to aeroallergens and cross-reactive antibodies recognizing homologous epitopes in fruits (ie, Pru p 1 in peach), vegetables (ie, Api g 1 in celery), or other plant-derived, heat-labile food proteins (ie, Ara h 8 in peanut) 13–16 . A local IgE-mediated response leads to an immediate sensation of oropharyngeal pruritus after food contact or ingestion, which is sometimes accompanied by angioedema of the oral mucosa and abdominal discomfort 13,14 . Cooking or factory processing of the food can denature the conformational integrity of the culprit proteins, resulting in significant reductions in IgE-binding avidity, which generally renders the food harmless when consumed 14–16 .…”