OBJECTIVETo evaluate the efficacy of specific sublingual immunotherapy (SLIT) with Dermatophagoides farinae drops on children with allergic asthma and allergic rhinitis of the preschool and school-age groups of children and adolescents.

METHODThis study analyzed the efficacy of SLIT in 122 children (aged 3-14 yr) with house dust mites-induced allergic asthma and allergic rhinitis. According to the age, patients were defined as the preschool group ( ≤ 6 years old, n = 59) and school-age group (> 6 years old, n = 63). All children were treated with Dermatophagoides farinae drops for at least 2 years. Clinical observation and follow-up study were conducted during the treatment. Before and after SLIT for half a year, 1 year and 2 years, asthma symptom scores (day and night), rhinitis symptom scores and medication scores were evaluated. The adverse events were assessed during the study.

RESULTAfter SLIT for half a year, 1 year and 2 years, there were no significant differences between the preschool group (0.3 ± 0.5,0.0 ± 0.1,0.0 ± 0.0) and school-age group (0.3 ± 0.4,0.0 ± 0.1,0.0 ± 0.0) in day scores of asthma (Z value was -1.687, -0.613,0.000, all P > 0.05). There were no significant differences between the preschool group (0.2 ± 0.5,0.1 ± 0.3,0.0 ± 0.0) and school-age group (0.2 ± 0.4,0.1 ± 0.3, 0.0 ± 0.0) in night scores of asthma (Z value was -0.496, -0.486,0.000, all P > 0.05). There was no significant differences between the preschool group (1.4 ± 0.9,0.4 ± 0.5,0.1 ± 0.3) and school-age group (1.3 ± 0.9,0.5 ± 0.6,0.2 ± 0.4) in symptom scores of allergic rhinitis (Z value was -0.394, -1.166, -1.075, all P > 0.05). There were no significant differences between the preschool group (1.6 ± 0.8,0.0 ± 0.0,0.0 ± 0.0) and school-age group (1.7 ± 0.7,0.0 ± 0.0,0.0 ± 0.0) in medication scores of allergic rhinitis (Z value was -0.655,0.000,0.000, all P > 0.05). After SLIT for 2 years, most children in the preschool and school-age groups were no longer using asthma controlling medication, with no significant difference between the two groups (Z value was 0.000, P > 0.05). The overall incidence of adverse reactions was only 7%, and there was no significant difference in the incidence of adverse reactions between the two groups (χ(2) = 0.000, P > 0.05). The local adverse events were mild gastrointestinal discomfort and rash, a majority of local adverse events in the preschool group were diarrhea. No severe adverse events happened in the treatment.

CONCLUSIONSLIT with Dermatophagoides farinae drops is safe and effective in children with allergic asthma and allergic rhinitis of the preschool and school-age groups of children and adolescents, which provides evidences for early SLIT intervention of the disease.