Surveillance of antimicrobial resistance in clinical isolates from Hubei province in 2008

Objective: To investigate the resistance of clinical isolates from Hubei province to commonly used antimicrobial agents during 2008. Methods: Disk diffusion method was used to determine the antimicrobial susceptibility. Data were analyzed by WHONET 5.4 software. Results: A total of 24 272 clinical isolates were collected, including gram-positive cocci (32.7%) and gram-negative bacilli (63.1%). The top six pathogens were E. coli, coagulase-negative Staphylococcus, P. aeruginosa, S. aureus, Klebsiella spp. and Acinetobacter spp. The prevalence of MRSA and MRCNS were 56.1% and 79.3%, respectively. Several strains of Enterococcus with intrinsic resistance to vancomycin were found. The resistant rates of Enterobacteriaceae to cefoperazone-sulbactam and piperacillin-tazobactam were lower than 20%. Three strains of K. pneumoniae were resistant to carbapenems. ESBLs-producing strains accounted for 65.1%, 44.7% and 25.3% in E. coli, Klebsiella spp. and P. mirabilis, respectively. Not more than 20% of P. aeruginosa and Acinetobacter spp. were resistant to cefoperazone-sulbactam. The prevalence of pan-resistant P. aeruginosa and A. baumannii was 1.8% and 8.0%, respectively. The resistance of Acinetobacter spp. to most antimicrobial agents other than SMZ-TMP, minocycline and cefoperazone-sulbactam was higher than that of P. aeruginosa. The resistance rates of S. maltophilia and Burkholderia spp. were 19.3%, 25.8% to SMZ-TMP, 4.1% and 54.5% to minocycline. Conclusions: Two thirds of these clinical isolates are gram-negative bacilli, for which carbapenems are highly active. The resistance to most antimicrobial agents is increasing in the clinical isolates, especially nonfermentative bacteria, from Hubei province.