It has been studied the effectiveness of macrolide azithromycin-Sumamed in the treatment of chlamidial infection in small bronchial tubes diseases at children. The ctudy involved 56 children aged 2 to 15 years. Of these, 17 children had chronic obliterative bronchiolitis, 39 patients were diagnosed with bronchial asthma. Given the identification of chlamidial infection in a diagnostically significant titres, previosly carried out by the inefficiency of antibacterial therpy in the treatment etiotropic was included sumamed. Conducted dynamic observation for 6 months showed that etiotropic sumamed therapy led to a marked positive effect in the clinical couse of disease. Immunomodulatory effect of sumamed manifested in a significant increase in phagocytic activity of granulosytes.