Allergy to plant-derived fresh foods in a birch- and ragweed-free area

Background Allergy to plant-derived fresh foods has often been reported in geographical areas where birch or ragweed pollens are frequent and has been attributed to cross-reactivity to pollens. Objective The aim of this study has been to evaluate allergy to plant-derived fresh foods among pollen-allergic patients from a birch and ragweed-free area. Methods Ninety-five pollen-allergic patients took part in the study. The study consisted of a questionnaire, skin prick tests and challenge tests. Pollen skin tests to five grasses, eight trees and seven weeds were performed in duplicate. Prick tests (prick by prick) and challenge tests were carried out with the fresh foods. Results Most patients allergic to pollens were sensitized to grass (Lolium and Phleum; 97.9%), followed by tree (Olea; 82.1%) and weed pollens (Plantago; 64.2%). 35 of the 95 pollen-allergic patients had positive skin test responses to some plant-derived fresh foods, the highest percentage corresponding to several fruits in the Rosaceae family (peach and pear, 26.3%), followed by Cucurbitacea fruits (melon, 13.7%). The 21.05% of the pollen-allergic patients were allergic to some type of plant-derived fresh food. Peach was the plant-derived fresh food which most frequently elicited allergy symptoms (12.6%), followed by melon (7.36%). The cluster of positive responses to Rosaceae fruits was higher for skin testing than for challenge testing. Conclusion Peach was the most important allergy provoking fruit in a birch and ragweed free-area where apples were consumed at a rate of two times more than peaches and the patients allergic to pollen were principally sensitized to grass pollens.