Antimicrobial Susceptibility Profile of Extended Spectrum Beta- lactamases Producing Enterobacteriaceae isolated from clinical samples refereed to the National Bacteriology and Mycology Reference Laboratory, Ethiopia

Background: Extended-spectrum beta-lactamase producing Enterobacteriaceae are very commonly reported all over the world. They are known to cause a huge challenge in the treatment and control of bacterial infectious diseases in many health care facilities. These genes not only confer resistance to oximino-cephalosporins and aztreonum but also, they make bacterial pathogens multidrug-resistant to other commonly available antimicrobial agents.   Objective: To determine the prevalence and antimicrobial susceptibility profile of Extended-spectrum beta-lactamase producing Enterobacteriaceae isolates recovered from clinical samples referred to the national clinical bacteriology and mycology reference laboratory of the Ethiopian Public Health Institute. Methods: A cross-sectional study was conducted on 371 Enterobacteriaceae culture- positive clinical specimens that were referred from August 2018 to July 2019. Bacterial isolation was performed according to the inoculation and incubation conditions of each clinical specimen and identifications of the isolates were performed using standardized biochemical tests for gram-negative bacteria. Antimicrobial susceptibility profiles of the isolated bacteria were determined using the disk diffusion method on Muller Hinton agar and the microbial production was detected using Clinical and Laboratory Standard Institute Screening and confirmation test. A double-disk synergy test was used for confirmation. Descriptive statistics was used to analyze the data. Results: Out of the 371 clinical specimens 240(64.7%) were positive for: extended-spectrum beta-lactamase production and the most prevalent species were Klebsiella spp 131(54.6%) followed by E. coli 79 (32.9%). Of the positive Klebsiella spp, 95 (72.5%) were obtained from blood specimens. Among the 79 E. coli isolates, 51 (64.6%) of them were isolated from urine. All the identified positive isolates were resistant to ampicillin and first to third generation cephalosporins. Less resistance rates were documented for carbapenems and amikacin. Conclusion: The prevalence of extended-spectrum beta-lactamase producing Enterobacteriaceae in this study was found to be alarmingly very high with all of them being multidrug resistant to most of the clinically available antimicrobial agents. Instituting a regular surveillance system that can catch such multidrug resistant pathogens and the implementation of antimicrobial stewardship and infection prevention and control measures in health care facilities is highly warranted.