The purpose of the trial is to asses the efficacy and safety of sublingual annual immunotherapy in children with bronchial asthma and/or allergic rhinitis allergic to house dust mites.

Allergen immunotherapy is currently the only one method of cause treatment of the IgE-dependent allergic diseases. Sublingual immunotherapy (SLIT) is the method which allows to give allergens via alternative oral route in patients home. Due to possibility of avoiding injection this therapy offers better relationship with pediatric patient. However efficacy and safety of sublingual immunotherapy are still important issues, especially in asthmatic children. The purpose of the trial is to asses the efficacy and safety of sublingual annual immunotherapy in children with bronchial asthma and/or allergic rhinitis allergic to house dust mites.

Inclusion Criteria:

• patients with bronchial asthma and/or allergic rhinitis allergic to house dust mites first diagnosed at least 2 years before the study

Exclusion Criteria:

• active respiratory tract infection requiring antibiotic treatment within 4 weeks before the study
• hospitalisation due to asthma exacerbation during the 3 months before the first visit
• known contraindications of SIT according to the EAACI
• previous allergen immunotherapy
• use of systemic corticosteroids
• other clinically significant pulmonary, hematologic, hepatic, gastrointestinal, renal, endocrine, neurologic, cardiovascular, and/or mental diseases or malignancy that either put the patient at risk when participating in the study or could influence the results of the study