An Italian 15-year single-center retrospective study on the distribution of peach fruit and pollen-related to peach fruit allergens in a population of north Italy.

Background. Peach allergy is a common cause of food allergy in Mediterranean populations, often linked to pollen sensitization. Longitudinal data on peach and inhalant allergen sensitization remain limited, especially in pediatric cohorts. This retrospective study evaluated allergen sensitization patterns in 9,986 patients attending IRCCS San Gerardo dei Tintori, Monza, from 2010 to 2024. Methods. Extract-based specific IgE levels were measured for peach fruit (Prunus persica, f95) and seven major inhalant allergens involved in cross-reactivity, including birch (Betula verrucosa, t3), ragweed (Ambrosia artemisiifolia, w1), and timothy grass (Phleum pratense, g6). Results. The most prevalent IgE sensitizations were to timothy grass (g6, 11%), ragweed (w1, 11%), and birch pollen (t3, 10%). Distinct sensitization profiles were observed between adults and children. Among 352 f95-positive patients, 50 (14.2%) (26 adults, 24 pediatrics) were monosensitized to peach, suggesting potential primary sensitization independent from pollen cross-reactivity. Longitudinal analysis revealed stable sensitization to major pollens but a marked increase in f95 positivity occurred after 2019, particularly in subjects aged 7–12 years. Conclusions. The identification of monosensitized pediatrics highlights the need for molecular diagnostic approaches to distinguish between secondary cross-reactivity and primary food allergy. These findings showed evolving sensitization trends, likely influenced by environmental or exposure-related factors, dietary and lifestyle. The study supports the need for continued epidemiological monitoring and the integration of molecular allergology in clinical practice to enhance personalized allergy management.