ABSTRACT
The aim of this study was to evaluate the clinical and immunologic effects of sublingual-swallow immunotherapy (SLIT). A six-month, multicenter, double-blind, placebo-controlled trial was carried out in 59 patients aged 6 to 18 years with allergic rhinitis who were sensitized to mites only. Patients were randomly assigned to placebo or SLIT with a standardized Dermatophagoides pteronyssinus (D.p.)/D. farinae (D.f) 50/50 extract. Nasal symptom scores and use of medications were recorded. Skin sensitivity, mite-specific IgE, IgG4, and IgG4/IgE were evaluated before and after treatment. The skin sensitivity, total nasal symptom scores and medication consumption did not differ significantly after treatment. Specific IgG4 (both p <0.001) and IgG4/IgE to D.p. and D.f (p = 0.010, p = 0.001, respectively) increased significantly in the treatment group. Specific IgE increased significantly in both placebo and SLIT groups after treatment but did not differ between the two groups. The medication was well tolerated. SLIT did not significantly improve clinical manifestations of allergic rhinitis when used for 6 months. We demonstrated SLIT did significantly increase specific IgG4 and IgG4/IgE compared to treatment with placebo.