The aim of this study was to determine antimicrobial susceptibility of recent clinical Stenotrophomonas maltophilia isolates from Korea, and to compare the activity levels of several combinations of antimicrobials. A total of 206 non-duplicate clinical isolates of S. maltophilia was collected in 2010 from 11 university hospitals. Antimicrobial susceptibility testing was performed using the Clinical Laboratory Standards Institute agar dilution method. In vitro activity of antimicrobial combinations was tested using the checkerboard method. The susceptibility rates to trimethoprim-sulfamethoxazole and minocycline were 96% and 99%, respectively. The susceptibility rate to levofloxacin was 64%. All of four antimicrobial combinations showed synergy against many S. maltophilia isolates. A combination of trimethoprim-sulfamethoxazole plus ticarcillin-clavulanate was most synergistic among the combinations. None of the combinations showed antagonistic activity. Therefore, some of the combinations may be more useful than individual drugs in the treatment of S. maltophilia infection. Further clinical studies are warranted to validate our in vitro test results.
Anti-Infective Agents/*pharmacology ; Gram-Negative Bacterial Infections/microbiology ; Hospitals, University ; Humans ; Microbial Sensitivity Tests ; Minocycline/pharmacology ; Ofloxacin/pharmacology ; Republic of Korea ; Stenotrophomonas maltophilia/*drug effects/isolation & purification ; Trimethoprim-Sulfamethoxazole Combination/pharmacology

BACKGROUND: A web-based surveillance of surgical-site infections (SSIs) in Korean Nosocomial Infections Surveillance System (KONIS) was performed to determine the incidence of SSIs after 15 operative procedures. METHODS: Forty-three hospitals participated in the surveillance system for 15 operative procedures. A year-round observation was carried out, and the duration of participation was shortened for 3 months unit. All data were collected using a real-time web-based reporting system. RESULTS: From July 2010 through June 2011, SSI surveillance data of 18,644 cases were collected from 43 hospitals. SSIs were found to occur in 2.10% of the total cases. The SSI rates after various surgeries were as follows: 4.49%, rectal surgery; 4.41%, colon surgery; 3.50%, gastric surgery; 3.12%, craniotomy; 1.25%, abdominal hysterectomy; 0.93%, laminectomy; 0.63%, cesarean section; 0.62%, gallbladder surgery; and 0.54%, vaginal hysterectomy. The interim results of implant-related surgery are given below as SSI rates: 3.78%, ventricular shunt operation; 3.23%, coronary artery bypass graft; 2.20%, cardiac surgery; 1.31%, spinal fusion; 0.96%, knee prosthesis; and 0.88%, hip prosthesis. CONCLUSION: The SSI rate was found to be 2.10% by the KONIS 2010. The maintenance of a surveillance system for SSI is very important, as it will help in decreasing SSIs via feedback to the involved surgeons and infection-control personnel.
Colon ; Coronary Artery Bypass ; Cross Infection ; Female ; Gallbladder ; Hip ; Hysterectomy, Vaginal ; Incidence ; Knee ; Surgical Procedures, Operative

BACKGROUND: In this report, we present the annual data of the intensive care unit (ICU) module of the Korean Nosocomial Infections Surveillance System (KONIS) from July 2009 through June 2010. METHODS: We performed a prospective surveillance of nosocomial urinary tract infections (UTIs), bloodstream infections (BSIs), and pneumonia (PNEU) at 116 ICUs in 63 hospitals by using KONIS. Nosocomial infection (NI) rates were calculated as the number of infections per 1,000 patient-days or device-days. RESULTS: We identified 3,965 NIs during the study period: 2,156 cases of UTIs (2,119 were urinary catheter-associated), 1,110 cases of BSIs (948 were central line-associated), and 699 cases of PNEU (410 were ventilator-associated). The rate of urinary catheter-associated UTIs (CAUTIs) was 4.75 cases per 1,000 device-days (95% confidence interval, 4.55-4.95), and urinary catheter utilization ratio was 0.86 (range, 0.859-0.861). The rate of central line-associated BSIs was 3.28 (range, 3.07-3.49), and the utilization ratio was 0.56 (range, 0.559-0.561). The rate of ventilator-associated PNEUs (VAPs) was 1.95 (range, 1.77-2.15), and the utilization ratio was 0.41 (range, 0.409-0.411). Although ventilator utilization ratio was lower in the hospitals with 400-699 beds than in the hospitals with 700-899 beds and more than 900 beds, the rate of VAPs were higher in the hospitals with 400-699 beds than in hospitals with 700-899 beds and more than 900 beds. The incidence of infections due to imipenem-resistant Acinetobacter baumannii increased from 43.6% to 82.5% since July 2006. CONCLUSION: The risk of acquiring VAP and CAUTI is highest in the ICUs of hospitals with 400-699 beds than that in hospitals with more beds. Imipenem-resistant A. baumannii was identified as an emerging gram-negative pathogen of nosocomial infections.
Acinetobacter baumannii ; Cross Infection ; Incidence ; Critical Care ; Intensive Care Units ; Pneumonia ; Urinary Catheters ; Urinary Tract Infections ; Ventilators, Mechanical

BACKGROUND: A nationwide prospective multicenter study was performed in Korea to determine the incidence and risk factors for surgical site infections (SSI) after craniotomies (CRAN), ventricular shunt operations (VS), gastric operations (GAST), colon operations (COLO), rectal operations (RECT), hip joint replacements (HJR), and knee joint replacements (KJR). METHODS: We collected data regarding demographics, clinical and operative risk factors for SSI, and antibiotics administered to the patients who underwent CRAN in 18 hospitals, VS in 19 hospitals, GAST in 19 hospitals, COLO in 19 hospitals, RECT in 19 hospitals, HJR in 24 hospitals, and KJR in 23 hospitals between January and December 2009. All the data were collected using a real-time web-based reporting system. RESULTS: The SSI rate of CRAN, VS, GAST, COLO, RECT, HJR, and KJR was 3.68 (22/1,169), 5.96 (14/235), 4.25 (75/1,763), 3.37 (22/653), 5.83 (27/463), 1.93 (23/1,190), and 2.63 (30/1,139), respectively, per 100 operations. The only significant risk factor for SSI after CRAN was postoperative cerebrospinal fluid leakage. The independent risk factors for SSI after GAST were multiple procedure, reoperation, infection of other sites, and transfusion. In HJR, the duration of preoperative hospital stay and operation time were longer, and the need for general anesthesia, transfusion, and steroid use and the incidence of contaminated/dirty wound, obesity, and infection of other sites were significantly increased in the infected group. In KJR, the duration of preoperative hospital stay was longer and the need for reoperation was significantly higher in the infected group, and in addition, the incidence of SSI was higher among males. CONCLUSION: The maintenance of surveillance on SSI is very important because surveillance provides valuable information to the surgeon and infection control personnel, which in turn helps decrease the incidence of SSI.
Anesthesia, General ; Anti-Bacterial Agents ; Colon ; Craniotomy ; Demography ; Hip Joint ; Humans ; Incidence ; Infection Control ; Knee Joint ; Korea ; Length of Stay ; Male ; Obesity ; Reoperation ; Risk Factors

BACKGROUND: In this report, we present the annual data of the intensive care unit (ICU) module of the Korean Nosocomial Infections Surveillance System (KONIS) from July 2008 through June 2009. METHODS: We performed a prospective surveillance of nosocomial urinary tract infections (UTI), bloodstream infections (BSI), and pneumonia (PNEU) at 101 ICUs in 57 hospitals using KONIS. Nosocomial infection (NI) rates were calculated as the numbers of infections per 1,000 patient-days or device-days. RESULTS: We identified 3,287 NIs during the study period: 1,787 UTIs (1,772 cases were urinary catheter-associated), 917 BSIs (797 were central line-associated), and 583 PNEUs (335 were ventilator-associated). The rate of urinary catheter-associated UTIs was 4.80 cases per 1,000 device-days (95% confidence interval, 4.58-5.03) and urinary catheter utilization ratio was 0.85 (0.849-0.851). Although the urinary catheter utilization ratios were lower in the hospitals with 400-699 beds than in the hospitals with 700-899 beds and more than 900 beds, the rates of urinary catheter-associated UTIs were higher in hospitals with 400-699 beds than in the larger ones. The rate of central line-associated BSIs was 3.27 (3.05-3.51) and the utilization ratio was 0.56 (0.559-0.561). The rate of ventilator-associated PNEUs was 1.86 (1.67-2.07) and the utilization ratio was 0.41 (0.409-0.411). The rate of ventilator-associated PNEUs was lower in July 2008-June 2009 than in July 2007-June 2008 and July 2006-December 2006. CONCLUSION: It appears that the KONIS influences the reduction in the rate of device-associated infections, especially ventilator-associated PNEU; therefore, ongoing targeted surveillance and infection control strategies are needed to control device-associated infections.
Cross Infection ; Gossypol ; Infection Control ; Critical Care ; Intensive Care Units ; Pneumonia ; Urinary Catheters ; Urinary Tract Infections

BACKGROUND: Emergence and spread of antimicrobial resistant bacteria make it difficult to treat infections. A rapid increase in antimicrobial-resistant bacteria has become a serious problem in many countries including Korea, and it is important to perform a nationwide study of antimicrobial resistance to obtain some basic data that will help solve these problems. The aim of this study was to determine the nationwide prevalence of resistance among frequently isolated bacterial pathogens in 2005 and 2006 in Korea. METHODS: We collected routine susceptibility data for medically important bacterial pathogens from 12 university and general hospital laboratories in Korea from April to September in 2005 and from January to June in 2006. Collected data was analyzed by patient group. RESULTS: The proportions of methicillin-resistant Staphylococcus aureus (MRSA) were 65% in 2005 and 72% in 2006, respectively. The resistance rates of Enterococcus faecium to vancomycin were 29% in 2005 and 24% in 2006. The non-susceptible rates of Streptococcus pneumoniae to penicillin were 68% in 2005 and 74% in 2006. The resistant rates of Escherichia coli and Klebsiella pneumoniae to the 3rd generation cephalosporin were 10~12% and 25~39%, respectively, in 2005 and 11~15% and 30~34% in 2006. In Citrobacter freundii, Enterobacter cloacae and Serratia marcescens, the resistance rates to 3rd generation cephalosporin were 23~31%, 32~34%, and 17~27%, respectively, in 2005 and 21~37%, 37~43%, and 13~31% in 2006. The resistance rates to imipenem and meropenem were 21% and 18%, respectively, in Pseudomonas aeruginosa and 18% and 25% in Acinetobacter baumannii in 2005; 29% and 20% in P. aeruginosa and 18% and 23% in A. baumannii in 2006. Cotrimoxazole and levofloxacin resistance rates of Stenotrophomonas maltophilia were 5% and 13%, respectively, in 2005 and 3% and 7% in 2006. There were no isolates resistant to 3rd generation cephalosporin and fluoroquinolone among non-typhoidal Salmonella in 2005. CONCLUSION: Antimicrobial resistance of medically important bacteria is still a serious problem in Korea. To manage the problem, a continuous nationwide surveillance and diversified investigation and effort have become more important.
Acinetobacter baumannii ; Bacteria* ; Citrobacter freundii ; Enterobacter cloacae ; Enterococcus faecium ; Escherichia coli ; Hospitals, General ; Humans ; Imipenem ; Klebsiella pneumoniae ; Korea* ; Levofloxacin ; Methicillin-Resistant Staphylococcus aureus ; Penicillins ; Prevalence ; Pseudomonas aeruginosa ; Salmonella ; Serratia marcescens ; Stenotrophomonas maltophilia ; Streptococcus pneumoniae ; Trimethoprim, Sulfamethoxazole Drug Combination ; Vancomycin

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.
Pseudomonas aeruginosa/drug effects/isolation & purification ; Microbial Sensitivity Tests ; Laboratories ; Korea ; Klebsiella pneumoniae/drug effects/isolation & purification ; Imipenem/*pharmacology ; Hospitals ; Gammaproteobacteria/*drug effects/isolation & purification ; Drug Resistance, Multiple, Bacterial ; Ceftazidime/*pharmacology ; Anti-Bacterial Agents/*pharmacology ; Acinetobacter/drug effects/isolation & purification

BACKGROUND: Recently, vancomycin-resistant enterococci (VRE) with the vanA genotype that are susceptible to teicoplanin have been described in Japan, Taiwan, and Korea. The investigators suggested three point mutations in the putative sensor domain of vanS or impairment of accessory proteins VanY and VanZ as an explanation for the VanB phenotype-vanA genotype VRE. In this study, we analyzed Tn1546-like elements to determine the molecular mechanisms responsible for the impaired glycopeptide resistance of clinical VRE isolates with VanB phenotype-vanA genotype from Korea. METHODS: From 2001 to 2004, 28 clinical isolates of Enterococcus faecium with VanB phenotypevanA genotype were collected from 8 different university hospitals in diverse geographic areas in Korea. For structural analysis of Tn1546-like elements, PCR amplifications for internal regions of Tn1546 were performed. The purified PCR products were directly sequenced with an ABI Prism 3100 DNA sequencer. RESULTS: The sequence data of the vanS regulatory gene revealed that none of the isolates had any point mutations in this gene. All 28 isolates had a complete or incomplete deletion of vanY gene. Of these, 13 strains represented a complete deletion of vanZ, and 2 strains showed the deletion of nucleotides near the end point of vanX. CONCLUSIONS: The mechanism of VanB phenotype-vanA genotype in VRE isolates from Korea is not point mutations of vanS but the rearrangements of vanX, vanY and vanZ.
DNA ; Enterococcus faecium ; Genes, Regulator ; Genotype ; Hospitals, University ; Humans ; Japan ; Korea ; Nucleotides ; Phenotype* ; Point Mutation ; Polymerase Chain Reaction ; Research Personnel ; Taiwan ; Teicoplanin

BACKGROUND: The aims of this study were to survey the nation-wide susceptibilities of Klebsiella pneumoniae isolates against ceftazidime and cefotaxime and to determine the prevalence of class A extended-spectrum beta-lactamases (ESBLs). METHODS: During the period of February to July 2004, K. pneumoniae isolates intermediate or resistant to ceftazidime and/or cefotaxime were collected from 12 hospitals in Korea. Antimicrobial susceptibilities were determined by the disk diffusion and the agar dilution methods and ESBL-production was by double-disk synergy test. Ceftazidime or cefotaxime-resistance determinants of the ESBLproducers were transfered to Escherichia coli J53 by transconjugation. Searches for class A ESBL genes were performed by PCR amplication. RESULTS: Among 212 clinical K. pneumoniae isolates, 172 (81%) isolates showed positive results in double-disk synergy test; the most prevalent ESBL was SHV-12 (n=104). Genes encoding ESBLs including SHV-2 (n=6), SHV-2a (n=17), CTX-M-3 (n=18), CTX-M-9 (n=6), CTX-M-12 (n=1), CTX-M- 14 (n=27), CTX-M-15 (n=3), and a novel CTX-M-type beta-lactamases were also detected. CONCLUSIONS: It is concluded that diversity of ESBLs in K. pneumoniae isolates are increasing in Korea. CTX-M-12 has never been reported in Asia, and a novel CTX-M-type ESBL has emerged.
Agar ; Asia ; beta-Lactamases ; Cefotaxime ; Ceftazidime ; Diffusion ; Escherichia coli ; Klebsiella pneumoniae* ; Klebsiella* ; Korea ; Pneumonia ; Polymerase Chain Reaction ; Prevalence

BACKGROUND: The aim of this study was to determine a nation-wide prevalence of Ambler class A and D extended-spectrum-lactamases (ESBL) in Klebsiella pneumoniae isolates in Korea. METHODS: During the period of April to May 2005, 189 isolates of K.pneumoniae were collected from 11 Korean hospitals. Antimicrobial susceptibilities to ceftazidime and cefotaxime were tested by the disk diffusion method, and ESBL production was determined by double-disk synergy test. Determinants of ceftazidime or cefotaxime-resistance were transferred to Escherichia coli J53 (azide-resistant) by transconjugation. Genotypes of class A and D ESBL genes were determined by PCR amplification and sequencing. RESULTS: One hundred-sixty isolates of K.pneumoniae showed positive results in double-disk synergy test. The most prevalent ESBL was SHV-12 (n=148). Also detected were genes encoding ESBLs including TEM-52 (n=1), SHV-2a (n=2), CTX-M-3 (n=15), CTX-M-9 (n=6), CTX-M-12 (n=2), CTX-M-14 (n=9), CTX-M-15 (n=1), PER-1 (n=1), GES-5 (n=3), and OXA-30 (n=2) beta-lactamases. CONCLUSION: With the emergence of CTX-M-12, PER-1, and OXA-30 beta-lactamases, the ESBLs in K.pneumoniae isolates are becoming more diverse in Korea.
beta-Lactamases ; Cefotaxime ; Ceftazidime ; Diffusion ; Escherichia coli ; Genotype ; Klebsiella pneumoniae* ; Klebsiella* ; Korea ; Polymerase Chain Reaction ; Prevalence