Phenotypic detection of extended spectrum beta-lactamase in multidrug-resistant Escherichia coli from clinical isolates in Niamey, Niger

Extended spectrum beta lactamase (ESBL) producing Enterobacteriaceae is one of the main causes of antibiotic treatment failure in hospitals. The aim of this study was to evaluate the prevalence of ESBL produced by multidrug-resistant (MDR) Escherichia coli isolated from various clinical samples (urine, stool, pus, blood culture) in the “Hôpital National de Niamey” and the “Hôpital National Lamordé” of Niamey, Niger. Samples were processed using standard bacteriological methods. Isolates were identified by biochemical tests and confirmed on API 20 E system (Bio-Mérieux, France). Antibiotic susceptibility was determined using the disk diffusion method on Mueller-Hinton (MH) agar plates (Liofilchem, Italy). Producing of extended spectrum beta-lactamase was performed using simple double-disk synergy test (DDST) and double-disk synergy test using cloxacillin. A total of two hundred and seventeen (217) multidrug-resistant E. coli were isolated from various clinical samples. Among these isolates, 57 (26.3%) were extended spectrum beta-lactamase producers. From clinical sources, prevalence of ESBL producing E. coli was observed in urine samples (26.7%), stool samples (26.3%), pus samples (25%) and blood samples (25%). ESBL producing E. coli were observed in the age groups under 5 years (24.9%), 26 to 45 (38.1%) and over 65 years (50%). This study showed a notable prevalence of extended spectrum beta-lactamase E. coli isolated from various clinical samples in two hospitals of Niamey, suggesting the rational and judicious use of antibiotics by clinicians.