RESUMO
<p><b>OBJECTIVE</b>To observe the dynamic changes of pulmonary function and inhaled corticosteroid (ICS) doses during subcutaneous immunotherapy (SCIT) with standardized house dust mite vaccine (Alutard) in children with mild to moderate allergic asthma.</p><p><b>METHODS</b>One hundred children with mild to moderate allergic asthma were randomized into SCIT group and control group for treatment with SCIT plus ICS and with ICS only, respectively. The pulmonary function and ICS doses were evaluated before and every 3 months during the 2 years of treatment.</p><p><b>RESULTS</b>No significant difference was found in the pulmonary functions between the two groups before the treatment (P>0.05). After 3 months of treatment, FEV1% and PEF% in SCIT group were significantly higher than those in the control group [(103.19∓2.07)% vs (97.52∓1.92)%, and (105.56∓3.21)% vs (96.35∓2.7)%, respectively]; at 21 months, FEF50% and FEF25% were significantly higher in SCIT group than in the control group [(105.69∓3.29)% vs (94.61∓3.12)%, and (106.60∓3.71)% vs (92.92∓3.31)%, respectively]. A significant difference was found in ICS doses between SCIT group and the control group after 9 months of treatment (147.14∓6.41 vs 170∓4.95 µg/day, P<0.05), and the difference increased as the treatment prolonged.</p><p><b>CONCLUSION</b>SCIT combined with ICS can improve the ventilation function of the large airways early after the commencement of treatment, but its effect on small airways can be delayed. SCIT for 2 years shows a good therapeutic effect and can reduce the doses of ICS in children with mild to moderate allergic asthma.</p>