Clinical and immunologic effects of sublingual immunotherapy on patients with allergic rhinitis to house-dust mites: 1-Year follow-up results

Background: There have been no data on sublingual immunotherapy (SLIT) in Asian patients with allergic rhinitis (AR) sensitized to house-dust mites (HDMs). This study aimed to investigate the efficacy and immunologic change after 12 months of SLIT in Korean patients. Methods: Fifty-eight patients, who had AR caused by Dermatophagoides pteronyssinus and Dermatophagoides farinae and who completed 12 months of SLIT were included. Symptom scores were evaluated before and after 12 months of SLIT, and medication scores were assessed throughout the study. Peripheral blood eosinophil counts, eosinophil cationic protein (ECP), total IgE, and specific IgE were also evaluated. Results: All of the symptoms of AR were significantly improved with reduced medication scores. In addition, there were significant decrements in peripheral blood eosinophil counts and ECP (p = 0.025 and p = 0.048, respectively). Specific IgE for D. farinae slightly increased (p = 0.019), whereas specific IgE for D. pteronyssinus and total IgE did not change significantly. Thirty-six (62%) of 58 patients were in the effective response group. Although not statistically significant, findings in the study showed that the effective response group had a tendency to have higher ECP levels before SLIT than the ineffective response group (p = 0.056). Conclusion: SLIT improved the symptoms and medication scores in Korean patients with AR from HDM. Laboratory parameters including eosinophil counts, ECP, and specific IgE for D. farinae seemed to be modified after 1-year SLIT. A high ECP level may be a useful parameter to predict the effectiveness of SLIT and select the patient for the treatment.