Distribution and antimicrobial resistance analysis of gram-negative bacteria in sterile sites

Abstract

Objective To investigate the clinical distribution and antimicrobial resistance of the gram-negative bacteria in sterile sites from Zhejiang Provincial People's Hospital. Methods The antimicrobial susceptibility test against common clinical antibacterial drugs in vitro for gram-negative bacteria in sterile sites of Zhejiang Provincial People' s Hospital from 2008 to 2012 were analyzed retrospectively, and the data were analyzed by WHONET-5 software. Results A total of 2 018 isolates were collected. The top 5 most common pathogens were Escherichia coli (586 strains, 29.0% ) , Klebsiella pneumoniae (413 strains, 20.5% ) , Acinetobacter baumannii (300 strains, 14.9% ) , Pseudomonas aeruginosa (192 strains, 9.5% ) and Enterobacter cloacae (92 strains, 4.6% ). The antimicrobial susceptibility test result showed low resistance rates of antibacterial agents for Enterobacteriaceae were amikacin (12.9%) , meropenem (14.1%) , imipenem (16.8%) , ertapenem (17.5%) and tigecycline (0-9.1%). Escherichia coli showed low drug resistance rates to ertapenem, tigecycline, amikacin, amoxicillin/clavulanic acid, meropenem, cefotetan, cefoxitin, cefoperazone/sulbactam, imipenem, nitrofurantoin and piperacillin/tazobactam, which were all under 15%. The resistance of Klebsiella pneumoniae was a prominent problem, except for amoxicillinclavulanic acid, the resistant rates to other complex preparation containing enzyme inhibitors and quinolones were all higher than 40%. The extended-spectrum β-lactamase strains of Escherichia coli and Klebsiella pneumonia accounted for 54.8% and 25.1%. Among non-fermentative bacteria, Acinetobacter baumannii showed low drug resistance to polymyxin B (0) and tigecycline (15.4%) , and the drug resistance rates of Pseudomonas aeruginosa to amikacin (9.2%) , tobramycin (10.9%) and gentamicin (19.0%) were low. Conclusions Antimicrobial resistance of the gram-negative bacteria is a serious problem, especially in Klebsiella pneumoniae and non-fermentative bacteria. The surveillance of antimicrobial resistance for the rational use of antibacterial agent should be further strengthened. Key words: Gram-negative bacteria; Sterile sites; Antimicrobial resistance; Antibacterial agent