The build-up phase outcome of subcutaneous immunotherapy for pediatric allergic asthma: A retrospective cohort study from Surabaya, Indonesia

Background: Subcutaneous immunotherapy (SCIT) is an established recommended treatment for allergic asthma. SCIT provides symptomatic relief, and it is potentially curative. Its build-up phase represents vital information to improve patient compliance and treatment outcomes. Aim: This study aims to assess the build-up phase outcomes of subcutaneous immunotherapy (SCIT) for pediatric allergic asthma. Methods: The retrospective cohort study comprised 65 children with allergic asthma due to house dust mites at the end of initial build-up phase of SCIT (3 months) from 2009 until 2012 at one hospital in Surabaya, Indonesia. Pre-SCIT clinical evaluation included skin prick tests for Der p 1 and Der f 1, eosinophil counts test, and the reversibility of forced expiratory volume in a second. The serum level of IFN-γ (TH₁ ), IL-4 (TH₂ ), TGF-β (T_regs ), and IL-17 (TH₁₇ ) were measured via enzyme-linked immunosorbent assays (ELISA) at the end of the initial build-up phase of SCIT. Results: Of the 65 samples, 48 (73.8%) exhibited significant improvement after three months, including 37 (56.9%) partially controlled asthma as against 11 (16.9%) controlled one, respectively. Eosinophil counts, IL-4, and IL-17 levels were higher among subjects who did not have an improvement, whereas they showed lower IFN-γ levels and smaller wheal diameters for either Der p 1 or Der f 1. Total IgE and TGF-β levels were not significantly different according to the asthma refinement. Conclusion: At the end of the build-up phase, SCIT facilitated improvement in most subjects with allergic asthma, and the outcome was associated with eosinophil counts, wheal diameters for Der p 1 and Der f 1, as well as IFN-γ, IL-4, and IL-17 levels.