Occurrence multidrug resistance (MDR) in commensal Escherichia coli strains in patients with colorectal cancer

Background and Aim : Antibiotic resistance is a serious problem for health. On one hand, because E.coli is a versatile species containing both highly virulent and commensal strains and antibiotic resistance inducer genes are transferable between the Enterobacteriaceae family, It is of importance to identify factors that are responsible for pathogenicity. And the other hand E.coli as one of the components of gut microbiota, in comparison with healthy people, it,s population is increased in the gut of people with colorectal cancer or CRC. Our study aimed to investigate the antibiotic resistance and proteome profile of MDR and susceptible isolates of E. coli flora from people who have colorectal cancer.Methods : ۲۰ and ۵۰ gut flora E.coli isolates from CRC patients and healthy people were cultured and antibiotic susceptibilities were determined by the disc diffusion method. The discs used in this study were Sulfamethoxazole(SXT), Tetracycline (TE), Ciprofloxacin (CP), Amoxicillin (AMX), Nalidixic acid (NA), Cotrimoxazole (CTX), Ampicillin (AM), Ceftazidime (CAZ) and Kanamycin A (K).Results : Among the isolates of the healthy group, first place for the most sensitivity and resistance in order belonged to Ciprofloxacin (CP) and Ampicillin (AM). While in the other group, almost sensitivity and resistance were for Ceftazidime (CAZ) and Sulfamethoxazole (SXT) respectively.Conclusion : Among these isolates in both groups of patients and control, the difference in frequency of antibiotic resistance for ۷ antibiotics was significant and in both groups more than ۹۰% of commensal E.coli strains were MDR.

Keywords:

Antibiotic resistance , MDR , gut flora , Escherichia coli , colorectal cancer , CRC