Antimicrobial susceptibility patterns of E. coli from clinical sources in northeast Ethiopia

Escherichia coli is the leading cause of urinary tract, ear, wound and other infections in humans. Increasing rates of antimicrobial resistance among E. coli is a growing concern worldwide.

The aim of this study was to determine the prevalence and antimicrobial susceptibility of E. coli from clinical samples.

A retrospective review of culture results of urine, ear discharge, pus swab from wounds, and eye discharge was done. A total of 3,149 samples were analyzed for isolation and identification of bacteria and antimicrobial susceptibility testing.

E. coli was isolated from 446 (14.2%) samples. The highest isolation rate was obtained from urine samples 203 (45.5%). High resistance rates to erythromycin (89.4%), amoxicillin (86.0%) and tetracycline (72.6%) were documented. However, significantly high degree of sensitivity rates to nitrofurantoin (96.4%), norflaxocin (90.6%), gentamicin (79.6%) and ciprofloxacin were recorded (p<0.001). Multiple antimicrobial resistances of 74.6% and increased resistance rates to all antimicrobials except ciprofloxacin were also recorded.

E. coli isolates showed high rates of resistance to erythromycin, amoxicillin and tetracycline. Nitrofurantoin, norflaxocin, gentamicin and ciprofloxacin are considered appropriate for empirical treatment of E. coli in the study area. Regular monitoring of antimicrobial susceptibility is recommended.