1 – Serviço de Imunoalergologia, CHULC – Hospital Dona Estefânia
- Reunião Internacional, apresentação sob a forma de Poster, na European Academy of Allergy and Clinical Immunology Annual Congress, Lisboa, 1 a 5 de Julho de 2019
Introduction: Profilin is a minor allergen ubiquitously spread in pollen and plant food species. It can show cross reactivity between distantly related species, being responsible for many allergic sensitizations. The prevalence of profilin sensitization in pollen allergic patients in European countries has been estimated to be 10-30%. Although this pollen-food syndrome is frequently mild (oral allergic syndrome: OAS) more severe reactions might occur.
Objective: To evaluate clinical evolution over a 5 years (y) period of a group of patients sensitized to profilin.
Methods: In a 4 months period, patients with positive skin prick tests (SPT) to pollens, fruits or vegetables, performed SPT to profilin and LTP. The ones who were sensitized to profilin were selected, excluding co-sensitization to LTP to avoid bias. Evolution of symptoms, SPT, sIgE and ImmunoCap® ISAC were reviewed in a 5-year period.
Results: From a sample of 233 allergic patients sensitized to pollens / fruits / vegetables, there were 19 patients (8%) sensitized to profilin and 14 of them didn’t have LTP co-sensitization (median age 25y, 77% male). One was excluded due to lack of data. The median follow up was 5y (range: 2-5y). All 13 patients had rhinitis and were sensitized at least to grass pollen; none were under specific immunotherapy. Five of 13 patients (38%) had food allergy (FA) at the beginning: OAS (3), mucocutaneous manifestations (1) and isolated gastrointestinal symptoms (1). There were 3 cases of FA to melon, watermelon and peach; 2 to apricot, cherry, apple, pear, banana and orange and 1 to fig, kiwi, pineapple, lettuce and cress. Three patients had molecular allergen profile (primary sensitization to pollens, mainly grass, and cross reactivity between profilins); 4 patients maintained FA, one acquired tolerance and one has developed OAS after 3y of follow up. There weren’t new FA to fruits or vegetables in the remaining 214 patients.
Conclusions: The profilin sensitization prevalence is lower than expected and rises the need to perform large prevalence studies in the portuguese population. As expected, only less than 40% had FA and all reactions were mild. It was not found any parameter, including the molecular pattern of sensitization, with prognostic value regarding tolerance or FA acquisitions.
Palavras Chave: profilin, cross reactivity, food allergy, evolution