ESBLs Genotyping in Some Hospitals of Tianjin / 中华医院感染学杂志

OBJECTIVE To investigate the genotype characteristics of extended-spectrum ?-lactamases(ESBLs) producing Escherichia coli and Klebsiella pneumoniae and drug resistance condition in Tianjin.METHODS A total of 218 strains of ESBLs-producing E.coli and K.pneumoniae were isolated from clinic.The drug-resistant CTX-M-1,CTX-M-2,CTX-M-8,CTX-M-9,TEM,SHV,OXA-1,OXA-2 and OXA-10 were tested by SYBR GREEN Ⅰ real-time fluorescent quantitative Polymerase chain reaction(PCR).RESULTS Among 109 strains of ESBLs-producing E.coli,the drug resistance of genotypes CTX-M-1,CTX-M-2,CTX-M-8,CTX-M-9,TEM,SHV and OXA-1 was 32.1%,0.9%,0.9%,33.9%,73.4%,27.5% and 15.6%,respectively.The strains with more than two genes were 66.1%.The positive rate of CTX-M-1,CTX-M-2,CTX-M-8,CTX-M-9,TEM,SHV,OXA-1 and OXA-10 was 49.5%,2.8%,1.8%,22.9%,78.9%,76.1%,33.0% and 0.9%,respectively.The strains with more than two genes were 82.2%.The strains were highly sensitive to imipenem.CONCLUSIONS Most of the genotypes of ESBLs-producing E.coli and K.pneumoniae in Tianjin are SHV,TEM,CTX-M-1 and CTX-M-9.The rate of OXA are increasing,and the drug resistance genes of K.pneumoniae from different hospitals are different.

Phenotype and Genotype of Nosocomial Infection Strains of Klebsiella pneumoniae / 中华医院感染学杂志

OBJECTIVE To investigate the prevalence,antibiotic resistance and genotype of the extended-spectrum ?-lactamases(ESBLs)-producing clinical isolates of Klebsiella pneumoniae.METHODS A total of 104 isolates of K.pneumoniae were examined for the ESBLs production and the susceptibilities of the bacteria to 15 antimicrobial agents.PCR was performed to detect the genes encoding the ESBLs belonging to SHV and TEM families as well as CTX-M-1 and CTX-M-9 groups.RESULTS The ESBLs-producers of K.pneumoniae were 54.0% in the total of 104 isolates.Almost all of the ESBLs-producing isolates were resistant to the antibiotics commonly used,and only remained susceptible to carbapenems and the combination of cefoperazone with sulbactam.The genes of SHV,CTX-M-1 and TEM groups were detected in the ESBLs-producing isolates by 64.3%,46.4%,and 32.1%,respectively,and 35.7% and 8.9% of ESBLs-producing K.pneumoniae strains carried two and three genes.CONCLUSIONS The clinical isolates of K.pneumoniae in Tianjin Nankai Hospital are shown a high rate of ESBLs-producing and antibiotic resistance.SHV and CTX-M-1 groups of ESBLs are the dominant genotypes in the isolates of ESBLs-producing K.pneumoniae.