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Oral allergy syndrome in children

??Oral allergy syndrome??OAS?? is an IgE-mediated acute oropharyngeal hypersensitivity to food??which is caused by cross-reactivity between proteins in fresh fruits or vegetables and pollens??with a prevalence of 5% to 24 % in children. A variety of food protein antigens have been implicated in OAS. The most classic of these cross-reactive antigens include birch antigen Betv1??profilin and lipid transfer proteins??LTPs??. Symptoms are usually manifested as numbness??itching or swelling of the lips or mouth??itching or oedema of the lips?? throat??palate or gingiva??erythema of the face and tightness of the throat. OAS can be diagnosed based on clinical history??antigen-specific immunoglobulin E testing??skin prick testing and oral food challenge. If the diagnosis is established??patients should be instructed to avoid the fresh fruits and vegetables that cause symptoms??and emergency administration of epinephrine should be given for severe??generalized reactions.