Low Prevalence of Carbapenem Resistance in Clinical Isolates of Extended Spectrum Beta Lactamase (ESBL) Producing Escherichia coli in North Central, Nigeria

Extended Spectrum Beta Lactamase (ESBL) producing Escherichia coli is a global cause of life threatening infections. We determined the presence of ESBL and carbapenemase production in clinical isolates of E. coli and their antibiotic susceptibility. Clinical isolates of community and hospital acquired E. coli from 220 patients seen at a tertiary hospital were evaluated. Antibiotic susceptibility testing was by the modified Kirby-Bauer protocol while ESBL production was determined by the Double Disk Synergy Test (DDST). Carbapenem resistance was confirmed by the Modified Hodge Test. Of the 220 isolates, 122 (55.5%) were from females; 41 (18.6%) were ESBL positive. About 90% of the ESBL producing isolates were resistant to nine of the 15 antimicrobial agents tested. However, only one (2.4%) of the 41 ESBL producing isolates exhibited carbapenem resistance. The ESBL negative isolates were susceptible to Meropenem (100%), Cefepime (97.8%), Ceftriaxone (96.6%) and Cefotaxime (96.6%). All the ESBL producing isolates harbored detectable plasmids with sizes ranging from 2322 to 23,130 base pairs. Our findings show that although multidrug resistant ESBL producing E. coli are prevalent in both the hospital and the community in this environment, carbapenem resistance is still low. We recommend that institutions develop guidelines for the early phenotypic detection of ESBLs and carbapenem resistance.