determination of mcr-1 gene and antibiotic-resistant escherichia coli isolates from clinical and non-clinical samples

Background: in recent years, resistant infections and antibiotic resistance in livestock have been increasing, and it seems that these issues will cause more problems in the future. objectives: this study investigates the association between the pattern of escherichia coli antibiotic resistance (ecar) and the identification of the mobilized colistin resistance (mcr-1 gene) among clinical and non-clinical samples. methods: in this study, 265 samples were collected from clinical (human urine, n = 79) and non-clinical sources (animal feces from poultry and livestock farms, n = 186). all samples were processed, and e. coli bacteria were isolated and identified. the agar dilution method was used to evaluate colistin resistance, and the presence of the mcr-1 gene was characterized among e. coli isolates. results: out of 265 samples (clinical and fecal), 37.97% (30/79) of clinical samples and 37.63% (70/186) of animal feces showed growth of e. coli. the highest number of e. coli isolates was found in feces from livestock farms (71.48%; 50/70). antimicrobial susceptibility testing (ast) of e. coli isolated from clinical samples showed that the highest resistance (46.66%) was to ciprofloxacin, and the lowest resistance (16.66%) was to colistin. analysis of polymerase chain reaction (pcr) data also showed that 60% of colistin-resistant isolates from clinical urine samples and 70% from animal feces samples were positive for the plasmid-mediated mcr-1 gene. conclusions: the findings indicate that the high frequency of the mcr-1 gene among both clinical and animal-collected isolates may be a significant factor in the development of colistin resistance among circulating e. coli isolates.