Peach pollen has been identified as a relevant allergen in areas of high cultivar. At least two major proteins are recognized as primary sensitizers: Pru p 3 and another one that we identify as Pru p X. Because pollens share allergens among them and with plant-derived food allergens, our aim was to study Peach tree pollen sensitization in a non-exposed population (Madrid, Central-Spain).
We evaluated patients in our Allergy Unit (November 2016-July 2017) reporting seasonal respiratory symptoms (RC/Asthma). The study included a panel of prevalent pollens and the panallergens Polcalcin and Profilin. In those patients with positive skin prick test (SPT) to at least one pollen we also tested Peach tree pollen. If positive, we also tested Pru p 3 and Pru p X.
From 320 cases included, the 16% of them had positive SPT to Peach tree pollen. From these, 33% were positive to Pru p 3 and none of them to Pru p X. Positive SPT to Polcalcin were found in the 33% of the cases and to Profilin in the 13%.
Peach tree pollen sensitization in patients with pollen allergy in our area is high with one third of the cases recognizing Pru p 3 but not a single case, Pru p X. Because this pollen is absent in the area where the study was undertaken, its sensitization can be explained via cross-reactivity among allergens of the LTP family and possibly other pan-allergens.