The drug resistance strains producing extended-spectrum β-lactamases and the genotype distribution of β-lactamases

Objective To investigate the drug resistance of Escherichia coli and Klebsiella pneumonia producing extended spectrum β-lactamases (ESBLs) and the genotype of ESBLs in Hangzhou. Methods MICs to 12 antibiotics of 51 strains of Escherichia coli and Klebsiella pneumonia producing ESBLs were detected by E test. All strains were collected in five hospitals of Hangzhou city. The genotypes of ESBLs were detected by PCR, sequencing and isoelectric focusing. Results The sensitive rates of 51 strains to Imipenem were 100.0%, and to Cefoperazone/ Sulbactam, Ceftazidime and Piperacillin/Tazobactam were 60.0%～80.0%. The sensitive rates to other antimicrobial agents were lower, for example that to Cefotaxime was only 5.9%. 47 strains produced CTX-M type ESBLs, most of that were CTX-M-14, others were CTX-M-3, CTX-M-24 and CTX-M-22. Conclusion The resistance of Escherichia coli and Klebsiella pneumonia producing ESBLs in Hangzhou were severe and CTX-M type ESBLs were the most common genotype.