Drug resistance and genotypes of Escherichia coli producing ESBLs and AmpC isolated from different sources in Taizhou, Zhejiang

Objective To understand the drug resistance, extended-spectrum -Lactamases (ESBLs) and cephalosporinase (AmpC) producing and relevant drug resistant genotypes of Escherichia coli, isolated from clinical samples, water samples from separated water supply system and stool samples of the workers engaged in food industry. Methods The drug susceptibility test of the strains isolated was conducted, the phenotypes of the positive isolates were detected with ESBLs and AmpC confirmatory tests and the drug resistant genes of the strains were detected by PCR amplification and sequence analysis. Results The drug resistant rate of the strains from clinical samples was highest, followed by those of the stool samples and the water samples. Six E. coli strains producing ESBLs were detected in 100 isolates from the water samples, the drug resistant genotypes were TEM-1 + CTX-M-9, seventeen E. coli strains producing ESBLs and three E. coli strains producing AmpC were detected in 100 isolates from the stool samples, the drug resistant genotypes producing ESBLs were TEM-1 + CTX-M-9, CTX-M-9 and the drug resistant genotypes producing AmpC were MOX-1, DHA-1, and thirty-three E. coli strains producing ESBLs and nine E. coli strains producing AmpC were detected in 100 isolates from clinical samples, the drug resistant genotypes producing ESBLs were TEM-1+ CTX-M-9, CTX-M-9, CTX-M-25 and the drug resistant genotypes producing AmpC were MOX-1, DHA-1and FOX-1. Conclusion The genotypes of E. coli producing ESBLs and AmpC isolated in the water sample from separated water supply system and in the stool samples of the workers engaged in food industry were similar to those of clinical samples.