OBJECTIVETo determine the antibiotics resistance, aminoglycoside-modifying enzymes and homology of high-level gentamycin resistant enterococcus in clinical specimens.

METHODSThe high-level gentamicin resistant (HLGR) isolates were screened by the agar method and the resistance of 14 antimicrobial agents was determined by K-B method. The aminoglycoside-modifying enzyme genes were detected by polymerase chain reaction (PCR). Pulsed-field gel electrophoresis (PFGE) was used to analyze the homology of HLGR isolates.

RESULTSThe ratio of HLGR was 64.2% (68/106). Among the HLGR,there were no isolates resistant to linezolid, vancomycin and tecoplanin, and Enterococcus faecium was more resistant to beta-lactam antibiotics and quinolone than Enterococcus faecalis. The positive rate of aac(6')-Ie-aph(2')-Ia was 92.6% and 3 isolates had the resistance gene mostly similar to aph(2')-Id. And among 51 HLGR isolates from the hospitalized patients, PFGE grouped 17 E. faecalis isolates into 4 clusters (A-D), and 33 E. faecium isolates into 8 clusters (A-H) with A cluster as predominant.

CONCLUSIONHLGR has become the important antibiotic resistance bacteria which results in nosocomial infection; and aac(6')-Ie-aph(2')-Ia is the main aminoglycoside-modifying enzyme gene which causes HLGR.

Drug Resistance, Bacterial ; genetics ; Electrophoresis, Gel, Pulsed-Field ; Enterococcus ; drug effects ; genetics ; Enterococcus faecalis ; drug effects ; genetics ; Enterococcus faecium ; drug effects ; genetics ; Gentamicins ; pharmacology ; Humans ; Kanamycin Kinase ; genetics ; Microbial Sensitivity Tests

The emergence of multi-drug resistant gram-positive cocci such as methicillin-resistant (MR) staphylococci, vancomycin-resistant (VR) enterococci, and vancomycin-intermediate resistant S. aureus (VISA) has given new urgency to the development of new antimicrobial agents. One of these is quinupristin/dalfopristin (Q/D). We decided to determine the susceptibility of gram-positive cocci isolated at two university hospitals in Seoul to Q/D and compare the results with eight other antimicrobial agents. We investigated 120 isolates of S. aureus including 49 MRSAs and one VISA, 120 isolates of coagulase negative staphylococci (CNS), 64 E. faecalis and 56 E. faecium, including seven strains of VR E. faecium. Minimum inhibitory concentrations (MICs) and minimal bactericidal concentrations (MBCs) for several antimicrobials, including vancomycin and Q/D, were determined by broth microdilution. All S. aureus including VISA were susceptible to Q/D. Q/D MIC90 for both methicillin-susceptible S. aureus (MSSA) and MRSA was 0.25 g/mL. 49 (87.5%) of 56 E. faecium including six of seven VR E. faecium were susceptible to Q/D. E. faecalis were not susceptible to Q/D (only 1.5% susceptible), but were inhibited by ampicillin (94% susceptible) or vancomycin (95%). CNS was susceptible to Q/D (96% susceptible) and vancomycin (100% susceptible). One of 38 staphylococci and two of 17 E. faecium were tolerant to Q/D. In conclusion, Q/D showed excellent activity against all species of gram-positive cocci including MRSA, VISA, and VR E. faecium except E. faecalis, and may provide a valuable option for the treatment of infections caused by these emerging nosocomial pathogens of gram-positive cocci.
Antibiotics/pharmacology* ; Antibiotics, Peptide/pharmacology* ; Coagulase/analysis ; Enterococcus faecalis/drug effects ; Enterococcus faecium/drug effects ; Human ; Korea ; Microbial Sensitivity Tests* ; Staphylococcus/enzymology ; Staphylococcus/drug effects ; Staphylococcus aureus/drug effects ; Support, Non-U.S. Gov'tn ; Virginiamycin/pharmacology* ; Virginiamycin/analogs & derivatives*

OBJECTIVETo investigate the homology and resistant mechanism of vancomycin-resistant Enterococci (VRE) isolates.

METHODSA total of 9 VRE isolates were collected from 2006 to 2007 at PUMC hospital. The susceptibility of these isolates to 10 different antibiotics including vancomycin was tested by E-test. These strains were processed by brain heart infusion agar screening in the presence of vancomycin (6 microg/ml), and were analyzed for genotypic characteristics using the multiplex PCR. The homology of the isolates was determined by pulsed-field gel electrophoresis (PFGE).

RESULTSAll the 9 VRE isolates were identified as Enterococci faecium. The visual analysis of PFGE patterns revealed 6 different PFGE types. The vanA gene was confirmed by PCR and sequencing in 9 VRE isolates, which were consistent between phenotype and genotype for glycopeptides resistance.

CONCLUSIONSOnly vanA genotype was detected in PUMC hospital. Clonal dissemination, horizontal gene transfer, and the selective pressure of antimicrobial agents may contribute to the increase of VRE.

Bacterial Proteins ; genetics ; Bacterial Typing Techniques ; Drug Resistance, Multiple, Bacterial ; Enterococcus faecium ; classification ; drug effects ; genetics ; isolation & purification ; Gram-Positive Bacterial Infections ; microbiology ; Humans ; Vancomycin Resistance

BACKGROUND: Accurate and early detection of vancomycin-resistant enterococci (VRE) is critical for controlling nosocomial infection. In this study, we evaluated the usefulness of a selective chromogenic agar medium and of multiplex PCR for detection of VRE, and both these techniques were compared with the conventional culture method for VRE detection. METHODS: We performed the following 3 methods for detecting VRE infection in stool specimens: the routine culture method, culturing in selective chromogenic agar medium (chromID VRE, bioMerieux, France), and multiplex PCR using the Seeplex(R) VRE ACE Detection kit (Seegene Inc., Korea) with additional PCR for vanC genes. RESULTS: We isolated 109 VRE strains from 100 stool specimens by the routine culture method. In chromID VRE, all the isolates showed purple colonies, including Enterococcus gallinarum and E. raffinosus, which were later identified using the Vitek card. All VRE isolates were identified by the multiplex PCR method; 100 were vanA-positive E. faecium, 8 were vanA- and vanC-1-positive E. gallinarum, and 1 was vanA-positive E. raffinosus. CONCLUSIONS: For VRE surveillance, culturing the isolates in chromID VRE after broth enrichment appears to be an accurate, rapid, and easy method for routine screening test. Multiplex PCR is relatively expensive and needs skilled techniques for detecting VRE, but it can be an auxiliary tool for rapid detection of genotype during a VRE outbreak.
Agar/chemistry ; Chromogenic Compounds/*chemistry ; Enterococcus/drug effects/genetics/*isolation & purification ; Enterococcus faecium/genetics/isolation & purification ; Feces/microbiology ; Genotype ; Humans ; Phenotype ; Polymerase Chain Reaction/*methods ; Reagent Kits, Diagnostic ; *Vancomycin Resistance

OBJECTIVETo summarize the clinical features of Enterococcus faecium meningitis in children.

METHODSThe clinical data of nine children with Enterococcus faecium meningitis were analyzed.

RESULTSIn all the nine children, Enterococcus faecium was isolated from blood, cerebrospinal fluid, or peripherally inserted central catheters; 6 (67%) patients were neonates, 2 (22%) patients were younger than 6 months, and 1 (11%) patient was three years and four months of age. In those patients, 56% had high-risk factors before onset, which included intestinal infection, resettlement of drainage tube after surgery for hydrocephalus, skull fracture, perinatal maternal infection history, and catheter-related infection. The main symptoms were fever and poor response. In those patients, 22% had seizures; no child had meningeal irritation sign or disturbance of consciousness. The white blood cell count and level of C-reactive protein were normal or increased; the nucleated cell count in cerebrospinal fluid was normal or mildly elevated; the protein level was substantially elevated; the glucose level was decreased. The drug sensitivity test showed that bacteria were all sensitive to vancomycin and the vancomycin treatment was effective. Only one child had the complication of hydrocephalus.

CONCLUSIONSEnterococcus faecium meningitis occurs mainly in neonates and infants. The patients have atypical clinical features. A high proportion of patients with Enterococcus faecium meningitis have high-risk factors. Enterococcus faecium is sensitive to vancomycin.

C-Reactive Protein ; analysis ; Enterococcus faecium ; drug effects ; Female ; Gram-Positive Bacterial Infections ; blood ; diagnosis ; drug therapy ; etiology ; Humans ; Infant ; Infant, Newborn ; Male ; Meningitis, Bacterial ; blood ; diagnosis ; drug therapy ; etiology ; Vancomycin ; pharmacology

INTRODUCTIONUntil recently, vancomycin-resistant enterococcus (VRE) infection or colonisation was a rare occurrence in Singapore. The first major VRE outbreak involving a 1500-bed tertiary care institution in March 2005 presented major challenges in infection control and came at high costs. This study evaluates the predictors of VRE carriage based on patients' clinical and demographic profiles.

MATERIALS AND METHODSStudy patients were selected from the hospital inpatient census population during the VRE outbreak (aged 16 years or more). Clinical information from 84 cases and 377 controls were analysed.

RESULTSSignificant predictors of VRE carriage included: age>65 years Odds ratio (OR), 1.98; 95% CI (confidence interval), 1.14 to 3.43); female gender (OR, 2.15; 95% CI, 1.27 to 3.65); history of diabetes mellitus (OR, 1.94; 95% CI, 1.14 to 3.30), and staying in a crowded communal ward (OR, 2.75; 95% CI, 1.60 to 4.74). Each additional day of recent hospital stay also posed increased risk (OR, 1.03; 95% CI, 1.01 to 1.04).

CONCLUSIONElderly diabetic females with prolonged hospitalisation in crowded communal wards formed the profile that significantly predicted VRE carriage in this major hospital-wide outbreak of VRE in Singapore. It is imperative that active VRE surveillance and appropriate infection control measures be maintained in these wards to prevent future VRE outbreaks.

Adolescent ; Adult ; Aged ; Aged, 80 and over ; Case-Control Studies ; Cross Infection ; drug therapy ; epidemiology ; microbiology ; Disease Outbreaks ; Enterococcus ; drug effects ; Enterococcus faecalis ; isolation & purification ; Enterococcus faecium ; isolation & purification ; Female ; Humans ; Infection Control ; Male ; Medical Audit ; Middle Aged ; Risk Factors ; Singapore ; epidemiology ; Streptococcal Infections ; drug therapy ; epidemiology ; Vancomycin ; pharmacology ; therapeutic use ; Vancomycin Resistance

PURPOSE: This study was aimed to describe a vancomycin-resistant enterococci (VRE) outbreak across three intensive care units (ICUs) of a Korean hospital from September 2006 to January 2007 and the subsequent control strategies. MATERIALS AND METHODS: We simultaneously implemented multifaceted interventions to control the outbreak, including establishing a VRE cohort ward, active rectal surveillance cultures, daily extensive cleaning of environmental surfaces and environmental cultures, antibiotic restriction, and education of hospital staff. We measured weekly VRE prevalence and rectal acquisition rates and characterized the VRE isolates by polymerase chain reaction (PCR) of the vanA gene and Sma1-pulsed-field gel electrophoresis (PFGE). RESULTS: During the outbreak, a total of 50 patients infected with VRE were identified by clinical and surveillance cultures, and 46 had vancomycin-resistant Enterococcus faecium (VREF). PFGE analysis of VREF isolates from initial two months disclosed 6 types and clusters of two major types. The outbreak was terminated 5 months after implementation of the interventions: The weekly prevalence rate decreased from 9.1/100 patients-day in September 2006 to 0.6/100 by the end of January 2007, and the rectal acquisition rates also dropped from 6.9/100 to 0/100 patients-day. CONCLUSION: Our study suggests that an aggressive multifaceted control strategy is a rapid, effective approach for controlling a VRE outbreak.
Decontamination ; Disease Outbreaks/*prevention & control ; Enterococcus faecium/*drug effects/isolation & purification ; Gram-Positive Bacterial Infections/drug therapy/*epidemiology/prevention & control ; Humans ; Intensive Care Units ; Patient Isolation ; Prevalence ; *Vancomycin Resistance

BACKGROUNDThe incidence of vancomycin-resistant enterococci (VRE) appeared to be increasing in China, but very few nosocomial outbreaks have been reported. Our hospital had experienced an outbreak of VRE since March 2008 to March 2009. The objective of this study was to analyze the molecular features of the isolates and the control measures used to eradicate a VRE outbreak in a tertiary institution in China.

METHODSWe characterized VRE isolates from 21 infected and 11 colonized inpatients from a single hospital by pulsed field gel electrophoresis (PFGE), multilocus sequence typing (MLST), the analysis of Tn1546-like elements and virulence genes detection. Infection control measures, including more environmental disinfection, screening for VRE colonization, contact precautions, education and strict antibiotic restriction, were implemented to control the outbreak.

RESULTSDuring the outbreak, a total of 32 VRE strains were obtained. There were 21 strains found in Emergency Intensive Care Unit (EICU), 9 isolates from Geriatric Ward, and two from other units. All the isolates harbored the vanA gene, however, four of them exhibited the VanB phenotype. Meanwhile, MLST analysis revealed that all isolates belonged to clonal complex (CC) 17. With the infection-control measures, the epidemic was constrained in two units (EICU and Geriatric Ward). After March 2009, no further case infected with VRE was detected in the following one-year period.

CONCLUSIONThe outbreak was controlled by continuous implementation of the infection control programme, and more rigorous infection control policy is needed.

China ; Electrophoresis, Gel, Pulsed-Field ; Enterococcus faecium ; drug effects ; genetics ; pathogenicity ; Gram-Positive Bacterial Infections ; microbiology ; transmission ; Hospitals ; Humans ; Microbial Sensitivity Tests ; Multilocus Sequence Typing ; Polymerase Chain Reaction ; Vancomycin Resistance ; genetics ; physiology

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.
Vancomycin Resistance ; Vancomycin/pharmacology ; Population Surveillance ; Microbial Sensitivity Tests ; Korea/epidemiology ; Klebsiella pneumoniae/drug effects/isolation & purification ; Klebsiella Infections/drug therapy/epidemiology/microbiology ; Imipenem/pharmacology ; Humans ; Gram-Positive Bacterial Infections/drug therapy/epidemiology/*microbiology ; Gram-Negative Bacterial Infections/drug therapy/epidemiology/*microbiology ; Gammaproteobacteria/*drug effects/isolation & purification ; Fluoroquinolones/pharmacology ; Enterococcus faecium/*drug effects/isolation & purification ; *Drug Resistance, Bacterial ; Anti-Bacterial Agents/*pharmacology ; Amikacin/pharmacology ; Acinetobacter Infections/drug therapy/epidemiology/microbiology ; Acinetobacter/drug effects/isolation & purification

No abstract available.
Aged ; Anti-Bacterial Agents/pharmacology/therapeutic use ; Bacteremia/blood/*diagnosis/microbiology ; C-Reactive Protein/analysis ; Cholecystitis/blood/cerebrospinal fluid/microbiology ; Electrophoresis, Gel, Pulsed-Field ; Enterococcus faecium/drug effects/isolation & purification/metabolism ; Humans ; Male ; Microbial Sensitivity Tests ; Microscopy, Electron, Scanning ; Ochrobactrum/drug effects/isolation & purification/*metabolism ; RNA, Ribosomal, 16S/analysis/genetics/metabolism ; Sequence Analysis, DNA ; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization