Surveillance On Distribution And Resistance Of Bacteria Isolated From Patients With Lower Respiratory Tract Infections (LRTI)

Objective To analyze the surveillance data on bacterial distribution and resistance of lower respiratory tract infections (LRTI). Methods 335 strains of bacterial were isolated from lower respiratory tract specimens in department of respiratory medicine from 2001 to 2003. VITEK 32 and Kirby-Bauer method were used for the identification and bacterial susceptibility testings. Results The most common pathogens were Klebsiella pneumoniae, Enterobacter cloacae, Pseudomonas aeruginosa, Acimetobacter baumanni and Escherichia coli. The prevalence of Klebsiella pneumoniae in the department was decreased, otherwise, the percentage of Pseudomonas aeruginosa increased to the first place (21.1%) in 2003. The most active antibiotics for 3 years was imipenem (with a susceptibility rate of 85.6%~100%), followed by tobramicin (79.3%), netilmicin (77.6%), and ceftazidime(75.5%). The antimicrobial resistance among Pseudomonas aeruginosa and Acimetobacter baumanni had increased. From 2001 to 2003, resistant rates of Escherichia coli against the third generateon cephalosporins (cefotaxime, ceftazidime) have increased markedly, 25% in 2001, 46.2% in 2002, and 75% in 2003, respectively. To Enterobacter cloacae, the antimicrobial resistance changed slightly. Conclusion Nosocomial gram-negative bacilli were the most common pathogens of the patients with LRTI. The prevalence and antimicrobial resistance among nonfermenting gram-negative bacilli have increased. It is very important to select antibiotics for the treatment of infection according to the results of Continuous surveillance of antimicrobial resistance.