Antibiotic resistance, phylogenetic group, and genotyping investigation in Escherichia coli strains of gut flora in patients with colorectal cancer in Iranian population

Abstract

Background: According to the World Health Organization, the prevalence of colorectal cancer (CRC) is the third-most common cancer in Iran. The population of Escherichia coli strains of the B2 phylogenetic group as one of the components of gut microbiota is increased in the gut of people with CRC and can also play a role in the process of cancerous intestinal cells or malignancy. The most common concern about treating infections and their association with cancer is multidrug resistance (MDR). Methods: In this study, stool samples of 20 patients with CRC were examined for sensitivity to 9 antibiotics and their genotypes were determined. Results: More than 90% of the isolates were MDR. Although among 20 isolates of E. coli gut flora in CRC patients, 11 (55%), 7 (35%), 0 (0%), and 2 (10%) strains belonged to phylogenetic groups B2, D, B1, and A, respectively. Conclusions: There was no significant relationship between the B2 phylogenetic group and MDR. Furthermore, the closeness of the species based on >90% similarity, seven clusters were observed that among five clusters, similarities were observed in terms of the phylogenetic group.