Background: In a previous double-blind placebo-controlled study, we analyzed a high-dose sublingual immunotherapy (SLIT) ultrarush protocol in asthmatic children monosensitized to grass pollen. In the present open-label study, we assessed the effect of SLIT on symptom score and nonspecific bronchial hyperreactivity in the same cohort followed for 1 subsequent year.

Methods: The study population comprised 35 children who were enrolled in our previous study. Placebo-treated patients were switched to active treatment; therefore, SLIT was administered for a further year to all patients. SLIT was considered effective if it reduced the severity of clinical symptoms and decreased the use of symptomatic medication. The effect of SLIT on nonspecific bronchial hyperreactivity (methacholine challenge test) was also measured.

Results: The symptom scores for asthma and rhinitis and medication score remained unchanged in the group who continued SLIT. We also observed further significant improvement in the results of the methacholine challenge test during the third year of treatment.

Conclusions: High-dose ultrarush SLIT reduced the severity of allergic symptoms in the first 2 grass pollen seasons but continuously improved bronchial hyperreactivity in children with asthma, suggesting that SLIT should be continued despite the lack of further improvement in clinical symptoms.

Key words: Asthma. Children. Immunotherapy. Rush. Sublingual.