Genotype Detection Of Extended-spectrum β-lactamases Of Escherichia Coli From Chicken And Chemical Treatment Of Bacterial-producing Infection

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, 2004 to October,2005, we did works as follows: Detecting ESBLs by NCCLS commended methods to 23 bacteria from clinical, inducing standards bacterias which donot producing ESBLs by sub-MIC, detecting MIC by duplation dilution, studying ESBLs gene type with amplified by PCR, selecting chemical medicine theraping to infecting ESBLs by simulating E.coli in combination with results of MIC.The resuls of experimentation showed 23 strains came from clinical including E.coli and Enterbacter cloacae were producing BLA, only 4 strains of E.coli were producing ESBLs , the rates of ESBLs is 17.39%(4/23). Standards strains that are not producing BLA and ESBLs and strains producing BLA could producing BLA and ESBLs after inducing by sub-MIC cefalosporins.All strains including clinical and induced strains did not detected AmpC.When standard strains were induced producing ESBLs ,MIC to 20 antibiotics transformated promineced from sentivity to resistance.The rates of producing ESBLs strains to 19 antibiotics are 25%～ 100%, which are higher than non-producing ESBLs strains.The sensitivity rates of carbapenem to producing and non-producing ESBLs are 100%.The producing ESBLs strains represent muldrug resistance and cross resistance.Antibiotics/β-lactam inhibitor and/or different antibiotics can improve distinctnessly against antibiotics activity of producing ESBLs strains.The producing ESBLs strains including clinical and induced strains could amplified 861 bp snippet by PCR with TEM-type down-object while SHV-type down-object did notThe result of sequences showed induced producing ESBLs strains mainly were TEM-116 ESBLs ,and clinical producing ESBLs strains were TEM-96 ESBLs. We found newe TEM-types in induced and clinical strains and named TEM-2V,TEM-3V,TEM-4V.The results of cherapy suggested that the rates about cure and efficient of β-lactam antibiotics , β-lactam antibiotics/β-lactam inhibitor,different anbitiotics combining were 21.20%～42.48% ,23.33%～ 46.67%; 30%～65.60%,33.33%～66.67%; 64.32%～78.67%,66.67%～80.00%。The results of therapy were in consistent to MIC, it offered basic pharmacology to new medication developing.