D1.87 - Kiwi allergy: A Comparative Analysis of Adult and Pediatric patients

Kiwi allergy is emerging worldwide. Clinical manifestations range from mild symptoms to anaphylaxis. The objectives of this study are to clinically and immunologically characterize a cohort of patients with kiwi allergy, comparing adult and pediatric patients followed between 2012 and 2022 to identify group-specific differences.

Retrospective single-center study of 50 patients (27 children, 23 adults [≥18 years]) with kiwi allergy history and positive specific IgE (sIgE). Collected data included age at first reaction, clinical manifestations, atopy (personal/family), aeroallergen/kiwi skin prick (SPT)/prick-prick tests (SPPT), other food allergies, total IgE, and multiplex immunoassay. Statistical analysis: Chi-square (proportions), Mann-Whitney U/Student's t-tests (continuous variables).

Mean age of first reaction was 5,5±5,96 years in children and 30±14,45 in adults. Oral allergy syndrome was the most frequent symptom in children (n=8; 29,6%), and cutaneous ones led in the adult group (n=9; 39,1%), mainly facial/tongue angioedema (n=4; 44,4%). Systemic symptoms (n (%); p value) exceeded local ones in adults (systemic: 15 (65,2%) | local: 8 (34,8%); p=0,03) and children (systemic: 19 (70,4%) | local: 8; (29,6%); p=0,03), without intergroup difference (p=0,914). Anaphylaxis occurred in 8 children (29,6%) vs. 4 adults (17,4%) (p=0,313). Children were mainly sensitized to Olea europaea (64,7%) and adults to Phleum pratense (50%) (p=0,151; p=0,781, respectively). Other food allergies were more common in adults (69,6% vs. 29,6%; p=0,002), mainly to fresh fruits (n=15 vs. n= 6; p=0,249). All patients with available in vivo testing had positive SPT and/or SPPT to Kiwi. Median sIgE kiwi was 3,77 kUA/L [IQR: 1,45-5,93] in children vs. 1,84 [IQR: 0,94-3,05] in adults (p=0,09). sIgE was higher in adults with systemic reactions versus local (p=0,02). Multiplex immunoassay revealed higher profilin (Phl p12/Bet v2) sensitization in adults (76.9% vs. 33,3%; p=0,04) while children were sensitized to Act d1/Act d2 (53,3% vs. 16,7% adults; p=0,11).

Systemic manifestations were prevalent in both groups. Children showed higher median kiwi sIgE, but within adults, patients with systemic symptoms had higher levels of sIgE. Adults showed higher prevalence of other food allergies (mainly fresh fruits) probably related to higher profilin sensitization. These findings suggest age-related differences in molecular sensitization patterns that may influence clinical management.