Phenotypic Detection of Extended-Spectrum ß-lactamase Produced by Escherichia coli Isolates from Health facilities in Otukpo, Benue State Nigeria

Beta-lactamase production by Escherichia coli and other bacteria is one of the most important mechanism of resistance to beta-lactam antibiotics such as Penicillins and Cephalosporins which are the most commonly used antibiotics in the treatment of bacterial infections in Hospitals. Resistance to antibiotics is emerging worldwide as a threat to human health resulting in limitations of therapeutic options. Susceptibility tests of microorganisms to antimicrobial agents do not reveal production of Extended-Spectrum ß-lactamase, hence the need to detect their presence by phenotypic or molecular techniques. This study is aimed at determining the prevalence of ESBL-production by Escherichia coli isolates from clinical samples collected from some selected health facilities in Otukpo, using phenotypic detection. Four hundred (400) specimens were collected from four different health facilities in Otukpo. Specimens collected included urine, blood, stool and wound swabs from 222 females and 178 males. Standard microbiological methods were employed for isolation, identification and characterization of Escherichia coli isolates from these specimens. Antibiotic susceptibility of the E. coli isolates was determined using Kirby-Bauer disc diffusion method while double disc synergy test (DDST) was used for ESBL production. Sixty-eight, (17%) of the 400 specimens tested for ESBL production were positive. Isolates from stool 22(22.7%) had the highest prevalence of ESBL-producing E. coli, followed by isolates from blood 4(21.4%). Urine isolates had the least prevalence 31(13.8%). Isolates from female subjects, 38(17.1%) had higher positivity rate than their male counterpart 30(16.9%). Otukpo General Hospital had the highest prevalence 20(20.0%) of ESBL followed by Otia Hospital 18(18.0%). Comprehensive health center, Otukpo had the least prevalence 14(14.0%). There is a high prevalence of ESBL production by Escherichia coli isolated from health facilities in Otukpo. Routine drug resistance surveillance therefore has become necessary to guide the appropriate and judicious antibiotic use.