Study On Extended Spectrum Beta-lactamases In Escherichia Coli Isolated From Abdominal And Cavity Biliary Tract

Partâ… Extended-spectrumβ-1actamases and resistance in Escherichia coli isolated from biliary tract and abdominal cavityBackground Soon after introducing the clinical use of extended-spectrum cephalosporins,such as cefetaxime,ceftriaxone,aztreonam,and so on,SHV₂ extended-spectrumβ-1actamases(ESBLs) were firstly isolated from Enterobacteriaceae in Germany in 1983.Then,reports about new ESBLs spread around the world.ESBLs were plasmid-mediated,which confferring bacteria resistance to many beta-lactams.It was generated by gram negative bacteria,could hydrolyze anoxyimino group of beta-lactam antibiotics such as third generation cephalosporin,aztreonam.The ESBLs which were early discovered mostly derived from TEM-1,TEM-2 and SHV-1.But for the past few years,it is reported that CTX-M has been increasing.The CTX-M is a species of non-TEM,non-SHV ESBLs.This kind of enzymes can hydrolyze cefotaxim which is better than ceftazidime.ESBLs were produced by Gram-negative bacteria,and the resistance of ESBLs-producing strains has currently become one of the most important nosocomial resistance problems in hospitals around the world.ESBLs have spread around the world from they were reported.The partly reason is the fact that we lack dependable test method.After third generation cephalosporin treatment failed,the people began to be aware of ESBLs existence.In order to control its epidemic,early detection of ESBLs is very important.We studied on resistance and prevalence of ESBLs-producing isolates,So that we could prevent regional epidemiology of ESBLs producers and guide clinical therapy.In view of lacking investigation about ESBLs and resistance in Escherichia coli isolated from biliary tract and abdominal cavity in Anhui province, we studied ESBLs and resistance in those isolates from biliary tract and abdominal cavity.Objective To investigate the prevalence of extended-spectrumβ-lactamases(ESBLs) and the resistance in Escherichia coli isolates from biliary tract and abdominal cavity.Methods Forty seveen isolates of E.coli were collected from biliary tract and abdominal cavity.ESBLs-producers were detected by CLSI Phenotypic Confirmatory Test and susceptibilities were tested by agar dilution method.Results 53.2%of isolates were ESBLs producers in those isolates.ESBLs producers were highly resistant to ampicillin,cefazolin,cefuoxime,fluoroquinolones,and cefotaxime.The resistant rate of ceftazidime,cefepime,cefoperazone-sulbactam, aimikacin,and cefrnetazole was less than 40%none was resistant to meropenem in ESBLs producers.The resistant rate of ampicillin,cefazolin,cefuoxime, fluoroquinolones was more than 40%and most were susceptible to other antimicrobial agents in non ESBLs producers.The resistant rate of ampicillin,cefazolin,cefuoxime, 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 Escherichia coli isolates from biliary tract and abdominal cavity,so more attention should be paid to survey and detect those strains. Partâ…¡Study on the genotype of ESBLs and molecular epidemiology in E.coli isolated from abdominal cavity and biliary tractBackground Since plasmid mediated ESBLs was first reported in1983 in German, many new ESBLs types have been detected around the world.By now,there have been many types of ESBL,including TEM,SHV,CTX-M,OXA and so on.The main type of ESBLs was different in countries and areas.Infection caused by ESBL producers increased year by year,and has been reported to cause epidemic outbreak in some hospitals.Resistance of ESBLs was the most important problem in clinic.SHV,TEM, CTX-M ESBLs have been reported all around the world,including Europe,South America,Middle East and Far East,as well as China.Epidemiology,resistance profile and type distribution of ESBL producing strains can help us preventing spreading of ESBL and guiding clinical therapy.Because cefotaxime was widely used in our country,it caused the spreading of ESBLs.In view of lacking investigation about epidemiology and genotype distribution of ESBLs in Escherichia coli isolated from biliary tract and abdominal cavity in Anhui province,we studied the genotype of ESBLs and molecular epidemiology in those isolates.Objective To study the genotype of ESBLs and molecular epidemiology in E.coli isolated from abdominal cavity and biliary tract.Methods Genotypes of ESBLs were determined by PCR and sequencing.The molecular epidemiology was screened by ERIC-PCR.Results In 25 ESBLs producers,the positive strains of CTX-M-2group+CTX-M-9group, CTX-M-8group+CTX-M-9group,TEM-1,TEM-1+CTX-M-1group+CTX-M-8group, TEM-1 +CTX-M-1 group,TEM-1+CTX-M-8group,TEM-1+CTX-M-9group, CTX-M-2group+CTX-M-9group,SHV-5+TEM-1,SHV-1,CTX-M-8group, TEM-1+CTX-M-2group+CTX-M-8group+CTX-M-9group,were 3,2,5,3,1,1,1,1,1, 1,1,1,respectively.The ERIC-PCR pattern was same in 2 isolates producing CTX-M-2group+CTX-M-9group.Conclusions CTX-M are the main genotype of ESBLs in E.coli isolated from abdominal cavity and biliary tract and clone spread is found in the few of them.