The geographic prevalence of local floral appears to be the most influential environmental factor in inducing sensitivity to fruits and vegetables. For example, in Italy, where hay-fever is caused mainly by grass pollen, there is an association between grass allergy and food allergy to tomato, melon, watermelon and orange, all of which are widely consumed in that country. In contrast, in the United States, where ragweed pollen abounds, an association between ragweed allergy and sensitivity to melon and banana has been reported. 12 Other known associations include allergy to kiwi fruit and grass pollen. Association with rhinitis or asthma due to pollen allergy.
Symptoms characteristically occur while or within minutes of ingesting the offending food.
Occasionally blisters may also be represented. 13 Foods implicated in anaphylaxis associated with OAS include lentils, tomatoes, apricot, peach, pear, cherry, apple, walnut and hazelnut. In most cases, the relationship between the contact of a food with the oral mucosa and the onset of symptoms is evident. Patients usually experience symptoms within 5-30 minutes after oral contact with the offending food.10 Reproducible symptoms after repeated contact with a particular food is typical. 19 Characteristics of the fruit and vegetable may influence the sensitivity of SPT in the diagnosis of food allergy.