Detection of partial virulence determinants and phenotypes in Enterococci / 中华检验医学杂志

Objective To investigate the incidence of six virulence determinants and two phenotypes in clinical strains of Enterococci.Methods PCR and dot blot were used to detect the six virulence determinants in 145 clinical isolates. The two phenotypes , including ?-hemolysis and gelatin hydrolyze ,were performed on agar plate containing 7% rabbit blood and Todd-Hewitt agar plate supplemented with 3% gelatin, respectively.Results In E. faecalis and E. faecium ,the rates of detection of the six virulence determinants were gelE72.9% vs 30.6%,efaA79.2% vs 36.7%,cylA54.2% vs 34.7%,esp34.4% vs 36.7%,agg 18.8% vs 0, ace28.1% vs 0, respectively; the ? hemolysis was 45.8% vs 20.4%,the gelatin hydrolyze was 35.4% vs 16.3%.Conclusions E. faecalis possess more virulence determinants and phenotypes than E. faecium do. The virulence determinants are more common among the strains isolated from urine sample than those from among sputum . Most of the E. faecalis carry virulence determinants of gelE,efaA and cylA .

Screening of high level aminnglycoside resistant enterococci and its therapy / 中华传染病杂志

Objective To establish the rational antibiotic treatment by accurate screening of highlevel aminoglycoside (HLA) resistant enterococci in clinical laboratory. Methods A single HLA gentamicin 500 μg/ml and streptomycin 200 μg/ml for agar dilution method, and gentamicin 120 μg/disk and streptomycin 300 μg/disk for disk diffusion method were used as parallel screening tests to detect high-level aminoglycoside resistance in 172 enterococci strains. Antibiotic time-kill test was performed to verify the accuracy and reliability of both methods. Results The resistant rates of the two methods for HLA gentamicin were 60.0％ and 59.3％, respectively. While for HLA streptomycin, both were 61.1%. In disk diffusion tests of 172 enterococci strains, the resistant rates for penicillin, ampicillin and vancomycin were 16.9 %,14.0%, and 1.7%, respectively. β-lactamase from 80 strains enterococci were all negative. Conclusion High-concentration aminoglycoside disk diffusion method is a simple, reliable method for screening the HLA resistant enterococci in clinical laboratory. The results can provide a rational base for physicians to treat enterococcal infections.

Screening of high level aminoglycoside resistant enterococci and its therapy / 中华传染病杂志

Objective To establish the rational antibiotic treatment by accurate screening of high level aminoglycoside (HLA) resistant enterococci in clinical laboratory. Methods A single HLA genta micin 500 ?g/ml and streptomycin 200 ?g/ml for agar dilution method, and gentamicin 120 ?g/disk and streptomycin 300 ?g/disk for disk diffusion method were used as parallel screening tests to detect high level aminoglycoside resistance in 172 enterococci strains. Antibiotic time kill test was performed to verify the accuracy and reliability of both methods.Results The resistant rates of the two methods for HLA gentamicin were 60.0% and 59.3%,respectively. While for HLA streptomycin, both were 61.1%. In disk diffusion tests of 172 enterococci strains, the resistant rates for penicillin, ampicillin and vancomycin were 16.9%, 14.0%, and 1.7%, respectively. ? lactamase from 80 strains enterococci were all negative. Conclusion High concentration aminoglycoside disk diffusion method is a simple, reliable method for screening the HLA resistant enterococci in clinical laboratory. The results can provide a rational base for physicians to treat enterococcal infections.