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OBJECTIVE To investigate the distribution and resistance of clinical isolates to antimicrobial agents commonly used.Antimicrobial agents should be used rationally based on the results of susceptibility testing.METHODS The clinical isolates were identified with W/A-40 or VITEK-32.The results were analyzed by WHONET 5.3 software according to CLSI 2005.RESULTS A total of 2892 clinical isolates were collected in 2007.Gram-negative bacilli accounted for 68.2% and Gram-positive cocci accounted for 31.8%.The top eight pathogens were Pseudomonas aeruginosa,Escherichia coli,Klebsiella spp,Acinetobacter spp,coagulase-negative Staphylococcus,Enterobacter spp,Serratia spp and S.aureus.About 76.4% of S.aureus isolates were MRSA,81.6% of coagulase-negative Staphylococcus isolates were meticillin-resistant.Under 20.0% of Enterobacteriaceae strains were resistant to cefoperazone/sulbactam,imipenem and piperacillin/tazobactam.About 16.3% and 32.5% of P.aeruginosa isolates were resistant to cefoperazone/sulbactam and imipenem.CONCLUSIONS Gram-negative bacilli were dominant isolates in our hospital during 2007.P.aeruginosa is the most frequent pathogenwith severe antibiotic resistance.Enterobacteriaceae are susceptible to cefoperazone/sulbactam and imipenem.
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OBJECTIVE To find out the imipenem-resistan metallo-?-lactamase in P.aeruginosa to provide the proof of treatment for clinic.METHODS A multi-disk was used to detect the metallo-?-lactamase of P.aeruginosa and the K-B disk method was used for monitoring of the antibiotic-resistance to 15 antibiotics.RESULTS Fifteen strains producing metallo-?-lactamase were isolated from 93 imipenem-resistant P.aeruginosa strains.The positive rate with metallo-?-lactamase was 16.1%(15/93).The susceptibility tests showed the lower resistance was to cefoperazone sulbactam(Sulperazone),amikacin and piperacillinl tazobactam(Tazocin).their resistance rate respectively was 16.8%,24.8% and 26.6%.The resistance rate to ciprofloxacin and ceftazidime was 43.7% and 33.6%.The resistance rate over 90.0% was to ampicillin,ampicilillin/sulbactam,cefazolin,cefpodoxime,cefuroxime and so on.CONCLUSIONS P.aeruginosa with imipenem-resistance shows seriou multidrug-resistance.The metallo-?-lactamase is the main reason for P.aeruginosa resistance to imipenem and cephalosporins.The doctors should choose antibiotics reasonably according to the susceptibility test when taking effective treatment to P.aeruginosa infection.
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OBJECTIVE To develop a macroarray method to detect pathogens in cerebrospinal fluid.METHODS According to the bacterial 16S rRNA genes,designed 10 kinds of specific probes and a pair of universal primers that can amplify rRNA gene of all bacteria.The tailed probes were spotted onto a nylon membrane.DNA was isolated from each pathogen,and subjected to UP-PCR to amplify target fragments,which were labeled with bio-16-dUTP at the same time.All those denatured fragments were hybridized to the probes on nylon membrane and visualized by AKP labeled avidin.The sensitivity and specificity of the system were detected.A total of 32 CSF samples,which were verified the bacterial infection by the routine method,were tested by this method.RESULTS It was sensitive to 10 CFU/ml when detecting Escherichia coli.Every kind of pathogens only reacted to its corresponding probes fixed on nylon membranes,which showed high specificity.The result of identifying 32 CSF clinical specimens accorded with that of routine method.CONCLUSIONS The method can screen out common pathogens in CSF sensitively and exactly.
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OBJECTIVE To study the distributive properties and susceptibility of yeasts to six antifungal agents. METHODS To analyze the distributive properties of 264 clinical Candida spp isolates and study the susceptibility to amphotericin B,nystatin,fluconazole,ketoconazole,miconazole and clotrimazole.The susceptibility of yeasts was tested according to the National Committee for Clinical Laboratory Standards guideline(NCCLS M27-A2). RESULTS Strains of Candida albicans were the most frequent organism isolated accounted for 62.5% of all the isolates.C.tropicalis,C.glabrata,and C.parapsilosis accounted for 20.8%,12.5%,and 1.9%,the others accounted for only 2.3%.The main infected organs were lungs,urinary tract,and digestive tract;the susceptibility tests showed strains of Candida spp to nystatin,amphotericin B,and fluconazole were more active than to the other antifungal agents.The resistance to triazole antifugal agents could be shown. CONCLUSIONS We should strengthen the diagnosis of Candida spp and strengthen the surveillance on susceptibility of clinical isolates Candida spp so as to help the doctors choose the antifungal agents reasonably.