The increased frequency of antibiotic resistance is known to be associated with
the dissemination of integrons in the Enterobacteriaceae. This study determined the prevalence
and type of integrons amongst 160 extended-spectrum beta-lactamase producing
enterobacterial isolates kept in our culture collection. Integrons were detected in 98(61.3%)
isolates, including 28(62.2%) Escherichia coli, 34(64.2%) Klebsiella spp., 27(61.4%), Enterobacter
spp. and 9(50.0%) Citrobacter spp. investigated in this study. Restriction analysis of the
integron gene fragments revealed that class I integron was the principal integron detected in
92(57.5%) of our isolates. Class II integron was detected in 6(3.8%) of our isolates, while no
class III integron was detected in this study. The high rates of integron prevalence particularly
of the class I integron in the E. coli and Klebsiella spp. concur with previous studies in other
geographical regions. The higher (>50%) integron prevalence of Citrobacter and Enterobacter
isolates comparing to previous studies suggests the potential of these isolates as sources for
dissemination of resistance determinants. The finding in this study serves as a basis for
further study on the antibiotic resistance mechanisms of enterobacterial species in this
teaching hospital.