OBJECTIVE To investigate the prevalence of meticillin-resistant Staphylococcus (MRS) isolates in Staphylococcus auricularis and S. hominis and detect their drug resistance. METHODS MRS isolates were detected by cefoxitin disc test and susceptibilities were tested by agar dilution method. RESULTS 94.7% and 91.7% MRS isolates were in S. auricularis and S. hominis. MRS strains were resistant to most of antimicrobial agents. There were no isolates resistant to vancomycin and teicoplanin. CONCLUSIONS MRS isolates are highly prevalent in S. auricularis and S. hominis with resistance to most of antimicrobial agents.

OBJECTIVE To investigate the prevalence of meticillin-resistant Staphylococcus haemolyticus(MRSH)and resistance in S.haemolyticus isolates. METHODS MRSH was detected by cefoxitin disc test and susceptibilities were tested by agar dilution method. RESULTS There were 86.4% of MRSH isolates.MRSH was highly resistant to penicillin,cefazolin,cefuroxime,ceftriaxone,tetracycline,ciprofloxacin,and clindamycin.The resistance rate to amikacin,rifampicine and chloramphenicol was 16.9%,11.2% and 28.1%,respectively.All isolates were susceptible to vancomycin and teicoplanin.Except for tetracycline,amikacin,rifampicin,and chloramphenicol,the resistant rate to other antimicrobial agents was significantly higher in MRSH than in MSSH. CONCLUSIONS MRSH is mostly occupied in S.haemolyticus isolates and resistant to most of antimicrobial agents.More attention should be paid to survey and detect these strains.

objective To detect MRSE and resistance in staphylococcus epidermidis isolates. Methods MRSE isolates were detected by cefoxitin disk test and susceptibilities were tested by agar dilution method. Results 79.7% of 128 isolates were MRSE strains with resistance to most antimicrobial agents, but those isolates were still susceptible to vancomycin and teicoplanin. Resistant rate in MRSE was higher than that in MSSE to most antimicrobial agents except penicillins, glycopeptides and macrolides. Conclusion MRSE with multi-resistance ale highly prevalent in staphylococcus epidermidis isolates and no isolate is resistant to glycopeptides.

Objective To investigate the resistance to fluoroquinolones and amikacin in escherichia coti isolates. Methods ESBLs-producers were detected by CLSI phenotypic confirmatory test and susceptibilities were tested by agar dilution method. Results 33. 8% of 361 isolates were ESBLs-producers. The resistant rate of ciprofloxacin,levofloxacin, amikaxin was 93.4%, 90.9%, 13.1% in ESBLs-produeers, and that was 69.5%,68.6 %, 19.7 % in non-ESBLs-producers, respectively. Conclusion Amikaxin is active against most escherichia coli isolates; those isolates are highly resistant to fluoroquinolones, especially, in ESBLs-producers.

OBJECTIVE To investigate the resistance of Pseudomonas aeruginosa strains to 5 ?-lactams.METHODS Susceptibility of 218 P.aeruginosa strains isolated from Anhui Province in 2005 to ceftriaxone,cefotaxime,ceftazidime,aztreonam,and piperacillin were tested by agar dilution method.RESULTS The resistance rate to ceftriaxone,cefotaxime,aztreonam,piperacillin,and ceftazidime were 59.2%,57.3%, 56.0%,51.8%,and 39.0%,respectively.There was statistically significant difference between ceftazidime and other 4 ?-lactams(P0.05).CONCLUSIONS Ceftazidime is the most susceptible antibiotic to P.aeruginosa strains among 5 ?-lactams tested.

OBJECTIVE To analyze the drug resistance of 141 clinical strains of Acinetobacter baumannii to 15 kinds of antimicrobial agents for the rational application of antimicrobial agents.METHODS All 141 strains of A.baumannii isolates were tested for minimal inhibitory concentration(MIC) to 15 kinds of antimicrobial agents included meropenem,imipenem,piperacillin,and so on using agar dilution method.RESULTS The lowest resistance rate of A.baumannii to the antimicrobial agents was to imipenem(22.7%),then was to meropenem and cefoperazone/sulbactam.The highest resistance rate was tetracycline(81.5%).The resistance rate to other antimicrobial agents was to about or more than 50%.CONCLUSIONS Most of A.baumannii isolates are susceptible to meropenem,imipenem,and cefoperazone/sulbactam and resistant to other antimicrobial agents,therefore,we should enhance to this kind of isolates detection.

OBJECTIVE To investigate the sensitivity to vancomycin of Enterococcus in clinic and the genotype and homology of glycopeptides-resistant strains.METHODS The sensitivity to vancomycin in 72 enterococci strains was detected with agar dilution;the existence of vanA,vanB,vanC1 and vanC2 in enterococci was detected by PCR and ERIC-PCR.RESULTS More than 50% of enterococci intermediated to vancomycin were resistant to other antimicrobial agents commonly used in clinic,except for teicoplanin and linezolid.Gene of vanC2 was present in two strains,but none with vanA and vanB.The ten strains of enterococci intermediated to vancomycin were divided into eight types,in which type A(3 strains) was isolated from the same hospital.CONCLUSIONS Multidrug resistance is observed in enterococci resistant to vancomycin,which are sensitive to teicoplanin and linezolid.Gene of vanC2 is found in some of them,suggesting clone transmission happen among strains.

OBJECTIVE To investigate the prevalence of extended-spectrum ?-lactamases(ESBLs) and the resistance in Escherichia coli isolates from biliary tract and abdominal cavity.METHODS ESBLs-producers were detected by CLSI Phenotypic Confirmatory Test and susceptibilities were tested by agar dilution method.RESULTS 50.1% Of isolates were ESBLs producers in those isolates.ESBLs producers were highly resistant to ampicillin,cefazolin,cefuroxime,fluoroquinolones,and cefotaxime.The resistant rate to ceftazidime,cefepime,cefoperazone-sulbactam,amikacin,and cefmetazole was less than 40%.None was resistant to meropenem in ESBLs producers.In non-ESBLs producers the resistant rate to ampicillin,cefazolin,cefuroxime,fluoroquinolones was more than 40% and most were susceptible to other antimicrobial agents.The resistant rate to ampicillin,cefazolin,cefuroxime,and ciprofloxacin was significantly higher in ESBLs producers than non-ESBLs producers.CONCLUSIONS With resistance to most of antimicrobial agents,ESBLs-producers were highly prevalent in E.coli isolates from biliary tract and abdominal cavity,so more attention should be paid to survey and detect those strains.

OBJECTIVE To investigate pathogens and their resistance in infective endocarditis patients.METHODS Pathogens and their resistance were detected by MicroScan WalkAway-40 system.RESULTS Most of pathogens were Streptococcus pyogenes and Staphylococcus.The resistant rate of S.pyogenes to tetracycline,erythromycin,ampicillin,penicillin,gentamicin and chloramphenicol was 78.6%,42.9%,14.3%,0,0 and 0,respectively.Four were MRS in 10 Staphylococcus isolates and they were resistant to most antimicrobial agents except vancomycin and higher than MSS.CONCLUSIONS Most of pathogens are S.pyogenes and Staphylococcus in infective endocarditis patients;most S.pyogenes isolates are resistant to tetracycline,erythromycin,but susceptible to penicillins;MRS are resistant to most of antimicrobial agents except vancomycin.

Objective To investigate the ESBL gene in a Klebsiella pneumoniae strain isolated from a patient in Huashan Hospital, Shanghai. Methods ESBL gene in the transconjugant from Klebsiella pneumoniae isolate was amplified by PCR. The PCR products were cloned into pHSG398 vector. The antibiotic susceptiblity and ?-lactamases activity of the clone strain were tested; The PCR product was sequenced and analyzed. Results The ESBL gene was identified as CTX-M-12 gene and CTX-M-12 is much more active against cefotaxime than against ceftazidine.Conclusions A clinical isolate of Klebsiella pneumoniae k99-442 isolated from a patient in Huashan Hospital, Shanghai produced ESBL type CTX-M-12 which caused this isolate resistant to most ?-lactams.