Genotype Detection Of Extended-Spectrum β-Lactamases And AmpC Enzyme Of Pathogens Isolated From Poultry

Due to cefalosporins is applying in clinical,such as ceftriaxone, the question about resistance of bacteria is worse than before,espectally about ESBLs. Because there has not many researchs in the worlds,we began this studying.From December 2005 to December,2006,we did works as follows:Detecting ESBLs by NCCLS commended methods to 20 bacteria from clinical,detecting MIC by duplation dilution and appling K-B disk diffusion method in susceptibility testing,studying ESBLs and AmpC beta-lactamases gene type with amplified by PCR.The resuls of experimentation showed that 20 pathogens isolated from poultry were identificated with VITEK-32 and were detected respectively for ESBLs and AmpC enzyme.The results revealed that there are 15 Escheria coli,1 Enterobacter cloacae,1 Pseudomonas aeriginosa,1 Citrobater farmeri,1 KlebsieUa pneumoniae and 1 Entercoccus gallinarum in the 20 pathogens.In these pathogens,the citrobacter farmeri,Klebsiella pneumoniae and Enterococcus gallinarum were first isolated from poultry in Veterinary。All of the 20 pathogens were producing BLA.only 10 clinical strains were producing ESBLs,including 8 Escheria coli,1 Klebsiella pneumoniae and 1 Entercoccus gallinarum, the rates of ESBLs in E coli is 53.3%(8/15).Entercoccus gallinarum were both producing AmpC beta-lactamases.The AmpC beta-lactamases-producing Entercoccus gallinarum is insensitive to Cephalosoorins(MICs=5μg/ml)but resistant to Amoxicillin and Aztreonam,and multresistance to antibiotics except for Fosfomycin,Levofloxacin, Gatifloxacin.The ESBLs-producing clinical strains could amplified 861 bp snippet by PCR with TEM-type and SHV-type down-object,But 905bp with CTX-type down-object.The AmpC beta-lactamases-producing Entercoccus gallinarum could amplified 466 bp snippet by PCR with EBC-type down-object.The result of sequences showed clinical ESBLs-producing strains mainly were TEM-116 ESBLs.We found four new TEM-type in Entercoccus gallinarum and Escheria coli,which named TEM-6V,TEM-7V,TEM-8V.TEM-9V,and one new CTX-type in Escheria coli named CTX-M-1V.