Distribution and antimicrobial resistance profile of the bacterial strains from lower respiratory tract / 中国感染与化疗杂志

ABSTRACT

Objective To examine the distribution and antibiotic resistance proifle of the bacterial isolates from lower respiratory tract of hospitalized patients for better empirical therapy.Methods A total of 3 155 lower respiratory tract specimens were collected from Respiratory Department of the First Afifliated Hospital of Chongqing Medical University in 2013 to identify bacterial pathogens for susceptibility testing. The results were compared with the data of 2011 and 2012.Results The top three bacterial species from lower respiratory tract in the period from 2011 to 2013 wereA. baumannii,P. aeruginosa, andK. pneumoniae. The prevalence ofS. aureusincreased, while the prevalence ofS. maltophilia andS. pneumoniae was still low.A. baumannii isolates were highly resistant to antibiotics. Not more than 40% of these strains were susceptible to the antimicrobial agents except minocycline, which was active against more than 60% of the ICU and non-ICU strains. More than 70% of theP. aeruginosa strains from non-ICU were susceptible to cefepime, meropenem, imipenem, levofloxacin, and ciprofloxacin in the three years, 50%-70% of the strains from ICU were susceptible to the antimicrobial agents tested. Carbapenem-resistantA. baumannii andP. aeruginosa strains were identiifed.S. maltophilia strains were relatively susceptible to minocycline and levolfoxacin. All the S. aureus isolates were susceptible to vancomycin, linezolid, and tigecycline. The prevalence of MRSA increased year by year. More than 80% of theK. pneumoniae andE. coli strains were susceptible to imipenem, piperacillin-tazobactam, and cefepime. ESBLs-producingK. pneumoniae was identified. More than 85% of theH. influenzae strains were susceptible to meropenem, ceftazidime, cefuroxime, ciprolfoxacin, levolfoxacin, and amoxicillin-clavulanate potassium. All theS. pneumoniae isolates were susceptible to vancomycin, and 80%-96% of these strains were susceptible to levofloxacin and penicillin.ConclusionsA. baumannii,P. aeruginosa, andK. pneumoniae are the top three bacterial species isolated from lower respiratory tract. Carbapenem-resistantA. baumannii,P. aeruginosa and ESBLs-producingK. pneumoniaeare emerging. The prevalence of MRSA is increasing year by year, which poses a challenge to antimicrobial therapy. It is urgent to contain and control the growing antibiotic resistance.