Prevalence of Antimicrobial-resistant to Tazocin Enterobacteriaceae Isolated from Blood / 中华医院感染学杂志

OBJECTIVE To investigate the prevalence of antimicrobial-resistant to(piperacillin/tazobactam Tazocin) enterobacteriaceae bacteria isolated from blood.METHODS Enterobacteriaceae isolates were isolated from blood specimens in our hospital from Jan 2003 to Dec 2008.The identification of Enterobacteriaceae isolates was performed by VITEK-32 Full Automated Microbiology Analyzer.Antimicrobial susceptibility test was determined by K-B disk diffusion test.RESULTS A total of 344 strains of Enterobacteriaceae isolates were obtained from blood,including 175 strains(50.9%) of Escherichia coli,129 strains(34.9%) of Klebsiella pneumoniae,39 strains(11.3%) of Enterobacter cloacae and 10 strains(2.9%) of Proteus mirabilis.The resistant rate of Enterobacteriaceae isolates to Tazocin was 15.1%.The resistant rates of E.coli,K.pneumoniae and E.cloacae to Tazocin were 16%,16.7%and 10.3%,but all isolates of P.mirabilis were sensitive to Tazocin.The resistant rates of E.coli and K.pneumoniae to Tazocin increased from 9.1% and 8.0% in 2005 to 22.7% and 21.6% in 2008.CONCLUSIONS Most of isolates including E.coli and K.pneumoniae are detected from blood.Tazocin has high antimicrobial activity for Enterobacteriaceae bacteria.The resistance of E.coli and K.pneumoniae to Tazocin is increasing gradually.

In Vitro Antibacterial Activity of Meropenem in Gram-negative bacilli / 中华医院感染学杂志

OBJECTIVE To investigate in vitro antibacterial activity of meropenem in Gram-negative bacilli isolated from clinical specimens.METHODS Gram-negative bacilli were isolated from various clinical specimens in our hosptial from Jan 2008 to Dec 2008.The identification test was determined by VITEK-32 Full Automated Microbiology Analyzer,the antimicrobiol susceptibility was detected by K-B method.RESULTS The resistance rate of Enterobacteriaceae to meropenem was extremly low.The resistance rates of Escherichia coli,Klebsiella pneumoniae and Enterobacter cloacae to meropenem were 0,27.6% and 4.2%.The resistance rates of Stenotrophomonas maltophilia,Burkholderia cepacia,Chryseobacterium meningosepticum,Pseudomonas aeruginosa and Acinetobacter baumannii to meropenem were 100.00%,48.81%,94.12%,21.85% and 31.72% respectively.CONCLUSIONS Meropenem has high in vitro antimicrobial activity to Enterobacteriaceae.but generally low to non-fermentative Gram-negative bacilli.

Prevalence of Antimicrobial-resistance to Cefoperazone/sulbactam in Gram-negative bacilli / 中华医院感染学杂志

OBJECTIVE To investigate the antibacterial activity of cefoperazone/sulbactam to Gram-negative bacilli in vitro.METHODS Gram-negative bacilli were isolated from various clinical specimens in our hospital from Jan 2004 to Dec 2007,screened by Gram-staining and oxidase test.The strain identification and the antimicrobial susceptibility test were determined by VITEK-60 Full Automated Microbiology Analyzer and slip diffusion method,respectively.The results of the survey were retrospectively reviewed.RESULTS The resistance rates of Enterobacteriaceae to cefoperazone / sulbactam were very low,the rates of Escherichia coli,Klebsiella pneumoniae and Enterobacter cloacae were 6.9%,9.2%and 12.9%,respectively;and the rates of Acinetobacter baumannii,Chryseobacterium meningosepticum,Pseudomonas aeruginosa,Stenotrophomonas maltophilia and Burkholderia cepacia were 7.7%,8.1%,20.4%,21.5% and 34.1%,respectively.CONCLUSIONS The antimicrobial activity of cefoperazone/sulbactam to Enterobacteriaceae and non-fermentation bacteria(A.baumannii,Ch.meningosepticum) is strong.The resistant rate of other Gram-negative bacteria to cefoperazone/sulbactam is less than 40 percent.In the treatment of infection caused by Gram-negative bacilli,cefoperazone/sulbactam has a very good prospect.

PER-1 Type Extended-spectrum ?-Lactamases Produced by Gram-negative Bacilli / 中华医院感染学杂志

OBJECTIVE To investigate the prevalence of PER-1 type ESBLs-producing Enterobacteriaceae and their antimicrobial-resistance profile. METHODS Totally 167 strains of Escherichia coli, 154 strains of Klebsiella pneumoniae and 67 strains of Enterobacter cloacae were tested. All of them were isolated from all kinds of clinical specimens in four hospitals of Nanchang city from Aug 2003 to Jun 2004. Antimicrobial susceptibility test(AST) was determined by K-B disk diffusion test. double-disk test(CTX, CTX/CA and CAZ, CAZ/CA)and three- dimension extract test were used to determine ESBLs. PER-1 genes were amplified by PCR. The products of PCR were sequenced to identify its ?-lactamase encoding gene. RESULTS Sixteen isolates were PER-1 gene positive. The PER-1 gene positive rates of E. coli, K. pneumoniae and E. cloacae were 3.6%, 3.2% and 9.0% , respectively . The antimicrobial-resistant rates of isolates harboring blaPER-1 to cefotaxime, ceftaxidime, amikacin , cefoxitin , cefepime and imipenem were 100%,100%, 56%, 94%, 31% and 0%, respectively. CONCLUSIONS blaPER-1 is detected in E. coli, K. pneumoniae and E. cloacace, and has diffused in Enterobacteriaceae . Imipenem and amikacin may be used to treat the infection caused by bacteria harboring blaPER -1.

Vicissitudes of Antimicrobial Resistance Profile of Burkholderia cepacia Isolated from Clinical Specimens / 中华医院感染学杂志

OBJECTIVE To investigate the antimicrobial resistance profile of Burkholderia cepacia isolated from clinical specimens in past 3 years.METHODS The B.cepacia strains were isolated from various clinical specimens by routine method from Jan 2004 to Dec 2006.In our hosptial the identification and antimicrobiol susceptibility test were determined by VITEK-32 Full Automated Microbiology Analyzer.RESULTS A total of 126 strains of B.cepacia were isolated.From them 75.14% and 15.08% of isolates were from lower respiatory tract and blood.All isolates were resistant to aminoglycosides,ampicillin,ampicillin/sulbactam,amoxicillin/CLAB,cefazolin,nitrofurantoin,and imipenem.The antibiotic resistant rates of the isolates to SMZ+TMP,cefepime,cefoperazone/sulbactam,meropenem,ceftazidime and piperacillin/tazobactam were 5.10%,16.99%,39.18%,39.61,39.65% and 48.12%,respectively.CONCLUSIONS The detection and antimicrobial resistance of the isolates of B.cepacia are increasing gradually.Multidrug resistance in the isolates of B.cepacia is serious.

Resistance and Molecular Epidemiology of Streptococcus pneumoniae / 中华医院感染学杂志

OBJECTIVE To investigate the drug resistance of clinical isolates of Streptococcus pneumoniae and molecular epidemiology with BOX-PCR in Nanchang. METHODS Antibiotic susceptibility was determined by the Etest methods or K-B disk diffusion test. Twenty-nine Penicillin-resistant S. pneumoniae(PRSP) clinical isolates were molecularly typed by BOX-PCR to detect the clonal relationship of them. RESULTS 85.7% were resistant to erythromycin,57.1% were PRSP. The resistant rates to tetracycline,clindamycin,trimethoprim-sulfamethoxazole and chloramphenicol were 88.1%,79.8%,60.7%,and 28.6%. Amoxicillin/clavulanic acid,levofloxacin and ceftriaxone retained activity against most of the isolates. All of strains were susceptible to vancomycin. Twenty-nine S. pneumoniae strains were divided into 14 distinct types,and 19 subtypes with subtype A (n=4) as the predominant type. CONCLUSIONS The resistance rate of S. pneumoniae to penicillin is very high,BOX-PCR typing demonstrats a high discriminatory potential and easy to be accurately analyzed.

Vicissitudes of Antimicrobial Resistance to Imipenem in Gram-negative Bacilli / 中华医院感染学杂志

OBJECTIVE To investigate the vicissitudes of antimicrobial resistance to imipenem in Gram-negative bacilli isolated from clinical specimens.METHODS Gram-negative bacilli were isolated from various clinical specimens in our hosptial from Oct 2003 to Jun 2006.The identification and antimicrobiol susceptiblity test were determined by VITEK-AMS Full Automated Microbiology Analyzer.RESULTS A total of 2045 strains of Gram-negative bacilli were isolated,including 35 species.From them 912 isolates of Enterobacteriaceae and 1120 isolates of non-fermenters accounted for 44.6% and 54.8%,respectively.The most predominant pathogens were Pseudomonas aeruginosa(21.1%),Escherichia coli(20.4%),Acinetobacter baumannii(14.2%),Klebsiella pneumoniae(9.4%),and Burkholderia cepacia(7.9%).The resistance rate of Enterobacteriaceae to imipenem was very low.The rates of Stenotrophomonas maltophilia,B.cepacia,Chryseobacterium meningosepticum,P.aeruginosa and A.baumannii to imipenem were 100.0%,98.6%,98.3%,22.3% and 20.6%.CONCLUSIONS Non-fermenters are predominant pathogens.Imipenem has high antimicrobial activity to Enterobacteriaceae in vitro,but not to non-fermenters.The resistance rates of P.aeruginosa and A.baumannii to imipenem increase gradually.