Molecular Characterization of Extended Spectrum β -Lactamase Genes in Clinical E. coli Isolates

Abstract

Extended Spectrum Beta-Lactamases (ESBLs) encoding genes (TEM, SHV and OXA) were amplified from multidrug resistance E. coli. The multidrug resistance E. coli isolates from different clinical sources were documented to be plasmid encoded and resistance against β-lactam and cephalosporin. Conventional laboratory analysis showed that seventy percent (70%) of the selected multidrug resistant clinical isolates were ESBLs positive, showing a ≥5 mm increase in zone diameter for either antibiotics compared to its zone when tested alone. The antibiotic susceptibility result showed that 100% of the isolates were resistant to amoxicillin-clavulanic acid, amoxicillin, cefuroxime and ampicillin-sulbactam while 90% of the isolates were resistant to ceftazidine and tetracycline, 80% to ofloxacin, 70% to ceftriazon, nalidixic acid, cefalexin, 60% to ciprofloxacin, 50% to nitrofurantoin, 40% to chloramphenicol and 20% to gentamicine.