Subcutaneous Immunotherapy in Patients with Fagales Pollen-Induced Oral Allergy Syndrome

Oral allergy syndrome (OAS) is the most common food allergy-related condition in adults. This study aimed to investigate whether subcutaneous immunotherapy (SCIT) with Fagales pollen-containing extracts can improve the clinical symptoms of OAS in Korea. In total, 56 OAS patients were included: 19 subjects treated with SCIT, which included Fagales pollen extracts, and 37 not treated with immunotherapy (IT). We reviewed the patients' medical records and administered a telephone questionnaire at one point to assess baseline OAS features and changes in the patients' OAS and allergic rhinoconjunctivitis (ARC) symptoms after treatment. Only 12 patients who received SCIT and 15 patients that did not receive SCIT could report on changes in OAS symptoms after treatment because the other patients practiced strict avoidance of their culprit fruits and vegetables, and they could not respond to the status of OAS. SCIT reduced the severity of OAS (p=0.005). Nine of the 12 patients (75%) that received SCIT reported a more than 50% reduction in OAS symptoms. In contrast, only three of the 15 patients (20%) that did not receive IT reported more than a 50% reduction in OAS symptoms. SCIT also reduced the severity of ARC symptoms (p<0.001). The results indicate that SCIT with Fagales pollen-containing extracts is associated with improved OAS symptoms in Korea.