Abstract
BACKGROUND: Allergen immunotherapy (AIT) is a well-established treatment for allergic diseases, particularly in patients with allergic rhinitis and asthma. In regions where patients are polysensitized, AIT can have broader immunomodulatory effects. This study investigates the impact of house dust mite AIT on IgE responses to both dust mites and non-target allergens, specifically Artemisia pollen, in polysensitized allergic rhinitis patients. METHODS: This retrospective study included polysensitized patients aged 18 or older with a diagnosis of allergic rhinitis or rhinitis with asthma and positive IgE for both house dust mites and Artemisia pollen. Patients who completed at least three years of AIT for house dust mites were included. IgE levels for Dermatophagoides pteronyssinus (Der p), Dermatophagoides farinae (Der f), and Artemisia pollen were measured at baseline and after 1, 2, and 3 years of treatment. Clinical outcomes were also recorded, including Total Nasal Symptom Score (TNSS), Visual Analog Scale (VAS), and medication use. RESULTS: Over three years, SIgE levels for Der p significantly decreased (p = 0.0001), while Der f showed a slight and significant decrease (p = 0.0334). Artemisia pollen-specific IgE decreased modestly (p = 0.0478), despite not being the target allergen. Total IgE levels increased slightly without statistical significance (p = 0.9026). Clinical outcomes improved significantly, with reductions in TNSS, VAS, and medication scores (all p < 0.0001), alongside a decrease in eosinophil counts, reflecting clinical and immunological benefits. CONCLUSION: House dust mite AIT not only reduces dust mite-specific IgE levels but also leads to unexpected reductions in IgE levels for non-target allergens, such as Artemisia pollen. This suggests that AIT has broader immunological benefits, improving overall tolerance to multiple allergens in polysensitized patients.