BACKGROUND: Clinical isolates of Escherichia coli were evaluated to determine the prevalence and genotypes of Ambler class A extended-spectrum beta -lactamases (ESBLs). METHODS: Clinical isolates of E. coli were collected from 12 hospitals from February through July, 2004. Antimicrobial susceptibility was tested by disk diffusion and agar dilution methods, and ESBLproduction was determined by double-disk synergy test. TEM, SHV, CTX-M, PER-1, VEB, IBC, GES, and TLA type ESBL genes were detected by PCR amplifications, and the PCR products were subjected to direct sequencing. RESULTS: The double-disk synergy test was positive in 90.9% (149 in 164) of the ceftazidime- or cefotaxime-resistant E. coli isolates. The most prevalent types of Ambler class A ESBLs in E. coliisolates were CTX-M-15 (n=53). CTX-M-14 (n=24), CTX-M-3 (n=9), CTX-M-9 (n=3), CTX-M-12 (n=3), SHV-2a (n=1), SHV-12 (n=5) and TEM-52 (n=3) were also found. CTX-M-12 ESBL had never been reported before in Korea. CONCLUSIONS: CTX-M type ESBL-producing E. coli isolates are spreading and CTX-M-12 is emerging in Korea.
Agar ; beta-Lactamases* ; Diffusion ; Escherichia coli* ; Genotype ; Korea ; Polymerase Chain Reaction ; Prevalence

BACKGROUND: This study was to evaluate a nationwide nosocomial infection rate and antimicrobial resistance in intensive care units(ICUs) in Korea. METHODS: The study was carried out at 16 university-affiliated teaching hospitals from July through October 2004. We performed a prospective multicenter study to investigate nosocomial infection rates, device-associated infection rated, and causative pathogens and their antimicrobial resistance. RESULTS: The urinary tract was the most commonly involved site. Nosocomial infection rate was 12.48 in medical. ICU (MICU), 9.59 in medical surgical ICU (MSICU), 14.76 in surgical ICU (MSICU), and 11.60 in other lCU. Device-associated infection rates were as follow: 1) rates of urinary catheter-associated urinary tract infection were 4.26 in MICU, 3.17 in SICU, 4.88 in MSICU, and 5.87 in other ICU; 2) rates of central line-associated bloodstream infection were 3.24 in MICU, 1.56 in SlCU, 2.36 in MSICU, and 1.78 in other ICU; 3) rates of ventilator-associated pneumonia were 3.61 in MlCU, 13.05 in SICU, 1.68 in MSICU, and 4.84 in other lCU. Staphylococcus aureus was the most frequently identified microorganism in this study; 93% of S. aurues were resistant to methicillin; 17% of Pseudomonas aeruginosa isolated were resistant to imipenem; 11% of Enterococcus faecium and 18% of Enterococcus faecalis showed resistance to vancomycin. Over a half of Acinetobacter spp, Stenotrophomonas maltophilia, Klebsiella pneumoniae, and Escherichia coli showed resistant to fluoroquinolone. Conclusion: This study shows the seriousness of antimicrobial resistance and the importance of infection control in the lCU in Korea. This study should provide a theoretical strategy to enforce the infection control.
Acinetobacter ; Cross Infection* ; Enterococcus faecalis ; Enterococcus faecium ; Escherichia coli ; Hospitals, Teaching ; Hospitals, University* ; Imipenem ; Infection Control ; Intensive Care Units* ; Critical Care* ; Klebsiella pneumoniae ; Korea* ; Methicillin ; Pneumonia, Ventilator-Associated ; Prospective Studies ; Pseudomonas aeruginosa ; Staphylococcus aureus ; Stenotrophomonas maltophilia ; Urinary Tract ; Urinary Tract Infections ; Vancomycin

Objective: To investigate the effects of a herb complex extract (HCE) prepared from Cornus officinalis Sieb. Et Zucc., Eriobotrya japonica Lindley, and olive leaves on immune response of mouse spleen NK cells in vitro and in vivo analysis. Methods: The activity of natural killer (NK) cells was measured in splenocytes and YAC-1 cells. Mice were immunosuppressed using cyclophosphamide (5 mg/kg body weight). Three different doses of HCE (200, 400, and 800 mg/kg body weight) and red ginseng extract (800 mg/kg body weight) which was used as standard immunomodulatory herb were administered orally for 4 weeks. The body weight, dietary, water intake, organs (liver, thymus, and spleen) weight, completed blood count, and cytokines (tumor necrosis factor alpha, interferon gamma, and interleukin-2) production was measured. Results: At the maximum concentration of HCE, the activity of NK cells was increased by 48.5%. HCE increased liver, spleen, and thymus weights without altering numbers of white blood cells, lymphocytes, and neutrophils in a cyclophosphamide-induced immunosuppression rat model. However, HCE recovered the inhibited cytokine expression; HCE (800 mg/kg) increased cytokines levels. The results indicate the immune enhancement potential of this HCE. Conclusion: The HCE enhances immunity by increasing NK cell activity, regulating cytokine levels, and maintaining spleen weight. Therefore, it may be used as a potential immunity enhancer.