AmpC Beta-Lactamase Prevalence in Isolates of Escherichia coli and Klebsiella pneumoniae in Enugu, Nigeria

Abstract

Background: Pathogenic bacteria with beta lactamase-resistant determinants have emerged, posing a worldwide health threat. They confer resistance to a large array of \(\beta\) -lactam agents and \(\beta\)-lactam inhibitors. Aim: This study evaluated the prevalence and resistance profiles of plasmid-mediated AmpC \(\beta\) -lactamase producing isolates among Escherichia coli and Klebsiella pneumoniae from clinical and environmental sources in the Enugu metropolis. Methodology: The work was done in the Microbiological Laboratory of the University of Nigeria Teaching Hospital Ituku-Ozalla. A total of 150 non-duplicate isolates processed in the microbiology laboratories of three referral hospitals and some private laboratories were used in this study including 85 and 65 isolates of Escherichia coli and Klebsiella pneumoniae respectively. Isolates were identified and characterized using standard microbiological protocols. Antimicrobial susceptibility was performed using the Kirby-Bauer disc diffusion procedure. Phenotypic detection of AmpC \(\beta\)-Lactamase production was determined using Cefoxitin/Cloxacillin double-disc synergy (CCDST). Results: Of the 67 isolates of E. coli from clinical samples, AmpC production was confirmed in 20(29.9%) and of the 18 isolates from environmental sources, only 5(27.8%) were confirmed. Of the 60 isolates of Klebsiella pneumoniae from clinical samples 16(26.6%) were AmpC producers while 1(20%) out of the 5 isolates from environmental samples was an AmpC producer. The prevalence of AmpC \(\beta\)-lactamase producers was 28%. There was no statistical difference in the proportion of AmpC producers in clinical and environmental isolates in E.coli and Klesiella pneumoniae p = .86 and p = .74 respectively. Antimicrobial resistance was high in both AmpC and non-AmpC \(\beta\)-lactamase producers. Impenem’s susceptibility was found in 75.4 percent of the isolates.
 Conclusion: This research revealed a high prevalence of AmpC beta-lactamase in the Enugu metropolis. The identification of AmpC beta-lactamase enzymes regularly is crucial to preventing therapeutic failures. The proper usage of antimicrobial drugs is critical.