Molecular Diversity and Extended Spectrum Beta-lactamase Resistance of Diarrheagenic Escherichia coli from Patients Attending Selected Health Care Facilities in Nasarawa State, Nigeria

Aims: This study investigated the molecular diversity and extended spectrum beta-lactamase resistance of diarrheagenic E. coli isolated from patients attending selected healthcare facilities in Nasarawa State, Nigeria.

Place and Duration of Study: Department of Microbiology, Nasarawa State University, P.M.B 1022, Keffi, Nasarawa State, Nigeria; between December 2017 and June, 2019.

Methodology: A total of 207 confirmed E. coli isolates (using standard microbiological methods) from loose stool samples of patients with suspected cases of diarrhea (69 from Federal Medical Centre Keffi [MCK] 69 from General Hospital Akwanga [GHA] and 69 from Dalhatu Araf Specialist Hospital Lafia [DASHL]) were included in this study.

Results: Phenotypic detection of ESBL production by β-lactam resistant isolates was done using double disc synergy test. Molecular detection of ESBL genes in phenotypically confirmed ESBL producers was done using Polymerase Chain Reaction. Out of 56 isolates jointly resistant to cefotaxime and/or ceftazidime and ciprofloxacin from DASHL, FMCK and GHA, 53.6% (30/56) were ESBL producers, distributed in relation to the hospitals as follows: blaCTX-M in DASHL was 6(66.7%), FMCK was 11(100.0%), and GHA was 10(100.0%); blaSHV in DASHL was 8(88.9%), FMCK was 7(63.6%), and GHA was 10(100.0%), and blaTEM in DASHL was 9(100.0%), FMCK was 10(90.9%), and GHA was 10(100.0%). Also, the occurrence of blaSHV was 100.0% in GHA but 88.9% in DASHL. The detection DEC was high in DASHL (88.9%) but low inGHA (58.8%). The occurrence of ETEC was high in GHA (60.0%) while EAEC was also high in FMCK (81.8%) and GHA (70.0%). The isolates were distributed into strain A – J based on RFLP pattern and the occurrence of strain A was high in GHA (70.0%) but low in DASHL (33.3%).

Conclusion: Most of the isolates were both diarrheagenic and ESBL resistant, and the predominant ESBL and pathotypes genes were blaCTX-M, blaTEM and EAEC. Further studies on molecular detection of sub-types of ESBL and sequencing of diarrheagenic pathotypes genes should be carried out.