RESUMEN
RATIONALE: Standardized allergen extracts are recommended for allergen immunotherapy. Since 2015, for patients with house dust mite allergies, we used a standardized house dust mite extract for subcutaneous immunotherapy, rather than non-standardized house dust extract. This study hypothesizes that standardized house dust mite extract (HDM group) was superior to non-standardized house dust extract (HD group) for subcutaneous immunotherapy. METHODS: In this noninterventional, retrospective study, we enrolled patients with allergic rhinitis and sensitization to house dust mites. The HDM group (27 patients) received subcutaneous standardized extract immunotherapy since 2015, and the HD group (37 patients) received non-standardized extracts before 2015. We assessed the safety and efficacy between the two groups; the safety was assessed by the systemic reaction (SR) rate. The efficacy was assessed by reductions in the allergic rhinitis symptom-medication score, and the asthma treatment score, over a year. RESULTS: The SR rate of the HDM group (44%) was significantly higher than that (14%) of the HD group. The HDM group displayed a 57% reduction in the allergic rhinitis symptom-medication score, which was markedly higher than the 40% reduction observed in the HD group. In the standardized group, there was a 66% reduction occurred in the asthma medication score, markedly higher than the 36% reduction observed among patients in the HD group. CONCLUSIONS: Standardized house dust mite extract was more effective than non-standardized house dust extract for subcutaneous immunotherapy; however, the establishment of safer methods is warranted.