Further Increase of Vancomycin-Resistant Enterococcus faecium, Amikacin- and Fluoroquinolone-Resistant Klebsiella pneumoniae, and Imipenem-Resistant Acinetobacter spp. in Korea: 2003 KONSAR Surveillance

Monitoring temporal trends of antimicrobial resistance can provide useful information for the empirical selection of antimicrobial agents to treat infected patients and for the control of nosocomial infections. In this study, we analyzed antimicrobial resistance of clinically relevant bacteria in 2003 at Korean hospitals and at a commercial laboratory. The following organism-antimicrobial agent resistance combinations were very prevalent: oxacillin-resistant Staphylococcus aureus (68%), expanded-spectrum cephalosporin-resistant Klebsiella pneumoniae (25%), and fluoroquinolone-resistant Escherichia coli (33%), Acinetobacter spp. (58%), and Pseudomonas aeruginosa (40%). Moreover, gradual increases in vancomycin-resistant Enterococcus faecium (20%), cefoxitin-resistant E. coli (10%) and K. pneumoniae (23%), and imipenem-resistant P. aeruginosa (20%) and Acinetobacter spp. (13%) were also observed. The resistance rates of Acinetobacter spp. to most antimicrobial agents at hospitals and at the commercial laboratory were similar. Among the Acinetobacter spp. isolated at a tertiary-care hospital, 46.2% were multidrug-resistant to 9-12 of 13 antimicrobial agents, and 18.3% were panresistant. The exclusion of duplicate isolates at a tertiary-care hospital significantly lowered the proportion of oxacillin-resistant S. aureus, vancomycin-resistant E. faecium, and fluoroquinolone-resistant E. coli.

High Prevalence of Ceftazidime-Resistant Klebsiella pneumoniae and Increase of Imipenem-Resistant Pseudomonas aeruginosa and Acinetobacter spp. in Korea: a KONSAR Program in 2004

A nationwide antimicrobial resistance surveillance has been conducted since 1997 in Korea. In this study, susceptibility test data generated in 2004 by KONSAR group hospitals were analyzed and compared to those at a commercial laboratory. In hospitals, the rank orders of organisms in 2004 were identical to those in 2003. The most prevalent species was Staphylococcus aureus (20.2%) in hospitals, but Escherichia coli (29.7%) in the commercial laboratory. The proportions of Enterococcus faecium to all isolates of Enterococcus faecalis plus E. faecium were 47.2% in hospitals and 24.9% in the commercial laboratory. The mean resistance rates of significant antimicrobial-organism combinations in hospitals were: oxacillin-resistant S. aureus (68%), oxacillin-resistant (penicillin- nonsusceptible) Streptococcus pneumoniae (68%), vancomycin-resistant E. faecium (25%), cefotaxime-resistant E. coli (14%), ceftazidime- and cefoxitin-resistant Klebsiella pneumoniae (34% and 32%, respectively), and imipenem-resistant Acinetobacter spp. and Pseudomonas aeruginosa (17% and 24%, respectively). In conclusion, oxacillin-resistant staphylococci, expanded-spectrum cephalosporin-resistant K. pneumoniae, and imipenem-resistant Acinetobacter spp. and P. aeruginosa were prevalent in 2004. Increasing trends were observed for vancomycin-resistant E. faecium, cefoxitin- resistant E. coli and K. pneumoniae, and imipenem-resistant Acinetobacter spp. and P. aeruginosa. Certain antimicrobial- organism combinations were also prevalent among the commercial laboratory-tested strains.