Antimicrobial Resistance of Clinically Important Bacteria Isolated from Hospitals Located in Representative Provinces of Korea / 대한임상미생물학회지

ABSTRACT

BACKGROUND: A rapid increase of antimicrobial-resistant bacteria has become a serious problem in many countries. The aim of this study was to determine the prevalence of resistance among frequently isolated gram-positive and -negative bacteria in Korea. METHODS: Data of routine antimicrobial susceptibility test for medically important bacteria, isolated during 3 months of 2002, were collected from 12 university and 1 commercial laboratories in Korea. RESULTS: The proportions of methicillin-resistant Staphylococcus aureus (MRSA) were 60-88%, but vancomycin-resistant S. aureus was not detected. Among the Enterococcus faecium isolates, the resistance rate to vancomycin was 29%. The resistance rates of Escherichia coli and Klebsiella pneumoniae 11% and 24% to cefotaxime, respectively, and 12% and 21% to cefoxitin, respectively. The resistance rates of Citrobacter freundii, Enterobacter cloacae, and Serratia marcescens 28%, 34% and 21% to cefotaxime, respectively, <1%, 8% and 14% to cefepime, respectively. The resistance rates of Acinetobacter baumannii and Pseudomonas aeruginosa were 65% and 37% to piperacillin, 64% and 19% to ceftazidime, 13% and 20% to imipenem, respectively. The resistant rates varied according to the hospital size. The resistance rates were generally higher among the isolates in the hospitals with more than 1,000 beds. The rates of penicillin-nonsusceptible Streptococcus pneumoniae were 58-90%. Among the Haemophilus influenzae isolates, 55-68% were resistant to ampicillin. CONCLUSIONS: Antimicrobial resistant strains were prevalent among the medically important clinical isolates, especially, MRSA, vancomycin-resistant enterococci, extended-spectrum -lactamase- or AmpC -lactamase-producing E. coli and K. pneumoniae, third generation cephalosporin-resistant C. freundii, E. cloacae and S. marcescens, imipenem-resistant A. baumannii and P. aeruginosa, penicillin-nonsusceptible S. pneumoniae and ampicillin-resistant H. influenzae. The antimicrobial resistance has become a serious problem in Korea.