Objective. Collection and analysis of the lower respiratory tract microflora nature in children aged 0—5 and 6—18 years and of resistance to the main classes of antibiotics.

Materials and methods. The bacteriological laboratories of the country health institutions and the Republican Reference Center for Monitoring Antibiotic Resistance using the WHONET program collected data and analyzed the species structure of 29 919 isolates (19 853 from children aged 0—5 and 10 066 from children 6—18 years old) isolated from sputum and tracheobronchial secretion. Profiles of resistance to the main classes of antibiotics were determined in 2362 isolates:
K. pneumoniae — 391 (16.55%), P. aeruginosa — 604 (25.58%), A. baumannii — 498 (21.08%), S. aureus — 756 (32.01%), and S. pneumoniae — 113 (4.78%).

Results. The study established the structure of the gram-positive and gram-negative bacteria isolated from sputum and tracheobronchial secretion. Among the gram-positive bacteria, streptococci, staphylococci, and enterococci were dominant and among the gram-negative bacteria K. pneumoniae, P. aeruginosa, A. baumannii, E.coli, and Enterobacter prevailed. The results of testing for sensitivity/resistance of bacteria from sputum to antibiotics indicated at high levels of their resistance to most antibiotics of the main classes. The bacterial strains isolated from the tracheobronchial secretion of children had higher levels of resistance (by 5—15%) compared with those isolated from sputum.

Conclusion. The results show that monitoring of clinically imported bacteria resistance to antibiotics in medical institutions of the country determined the spectrum of the microflora, the dominant groups of gram-positive and gram-negative bacteria, as well as profiles and levels of resistance to antibiotics. The data can be used for comparative evaluation of antibiotic resistance of the main species of clinically significant bacteria isolated from children with respiratory tract diseases in the hospitals of the country increasing the effectiveness of local monitoring as well as for more rational administration of antibacterial drugs.