Continuous surveillance of antimicrobial resistance among nosocomial gram-negative bacilli from intensive care units in China

CHEN Min-jun,WANG Hui, on behalf of China Nosocomial Pathogens Resistance Surveillance Study Group. Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing 100730, China  

Objective To investigate the change of antimicrobial resistance among nosocomial gram-negative bacilli, especially those of Enterobacteriaceae isolated from intensive care units from 1994 to 2001 in China. Methods E test was made to determine the minimal inhibitory concentrations (MIC) of 10 279 isolates of gram-negative bacilli (including 5 829 strains of bacilli of Enterobacteriaceae) from 32 hospitals in China from 1994 to 2001. Results The most common pathogens were Pseudomonas aeruginosa; Escherichia coli, Klebsiella spp, Acinetobacter spp. Enterobacter spp, and Stenotrophomonas maltophilia. The most common pathogens in respiratory tract specimens were Pseudomonas aeruginosa (25%), Klebsiella pneumoniae (18%), and Acinetobacter baumanni (11%). The most common pathogens in blood and urine specimens were Escherichia coli, Klebsiella pneumoniae, and Pseudomonas aeruginosa. The antibiotic remaining the most active against all of the gram-negative bacilli for 7 years was imipenem (with a susceptibility rate of 87%), followed by cefoperazone/sulbactam (however, with a susceptibility rate decreasing from 86% to 75%), amikacin (75%), ceftazidime (73%), cefepime (72%), and piperacillin/tazobactam (71%). The susceptibility rate of Escherichia coli Klebsiella pneumoniae to imipenem remained 98% with a MIC 90 of 0.5 μg/ml during the 7 years, much higher than those to amikacin (84%), ceftazidime (83%), cefoperazone/sulbactam (83%), piperacillin/tazobactam (80%), and cefepime (80% ). The susceptibility rate of these two species to cefoperazone/sulbactam decreased from 90% in 1996 to 74% in 2001. While the susceptibility to cefotaxime and ceftriaxone decreased from 82% to 57%. The susceptibility rate of Escherichia coli to ciprofloxacin decreased from 54% to 25% and that of Klebsiella pneumoniae to ciprofloxacin decreased from 90% to 75%. The prevalence of extended spectrum β-lactamases in these two species increased from 11% in 1994 to 34% in 2001. The most active antibiotics against Enterobacter cloacae were imipenem, cefepime, amikacin with the susceptible rates of 95%, 76%, and 70%, respectively; the susceptibility rates of Citrobacter freundii to imipenem, cefepime, amikacin, and cefoperazone/sulbactam were 94%, 80%, 80%, and 78% respectively. Only 40%～60% isolates of Enterobacter cloacae and Citrobacter freundii were susceptible to third-generation cephalosporins. Conclusion Imipenem remains highly active against Enterobacteriaceae, but the activities of other antibiotics have decreased in recent years.

【CateGory Index】： R446.5

Download(CAJ format) Download(PDF format)

CAJViewer7.0 supports all the CNKI file formats; AdobeReader only supports the PDF format.