1596 Five-year follow-up of basophil activation tests based on CD203c expression in cases with Pru p 7 allergy

Background: Allergy to peach gibberellin-regulated protein(GRP), Pru p 7, is severe and possibly enhanced by co-factors. In addition, recent studies suggested that 7 allergy could be due cross-reactivity with other GRPs, such as Japanese apricot GRP (Pru m 7), orange (Cit s 7) cedar pollen (Cry j 7). However, the natural history of remains unclear. this study, we investigated course basophil activation tests (BATs) over annual intervals. Methods: This study followed patients an native across 5 years. We purified ion-exchange column chromatography. performed BATs based on CD203c expression using (nPru Results: found two a also had sensitization, so documented them year timespan. Patient 1 was 57-year-old female developed several allergic reactions after ingesting peaches. The results nPru at μg/mL 19.5% in 2015, 19.1% 2016, 10.9% 2017 12% 2018. Since 2019, she has chronic urticaria prescribed antihistamines for her condition. 2021, condition improved, able stop medication. At time, 35.6%. 2 34-year-old 39.6% 2017, 6.0% 2018, 2.4% 2020 8.5% 2021. These suggest avoiding peaches, steadily improved. 10 16.9% Conclusion: indicate even years diagnosis, individuals show no negative BATs, meaning they were completely unable outgrow their allergy.