Enterobacteriaceae isolates from clinical and household tap water samples: antibiotic resistance, screening for extended-spectrum, metallo- and ampC-beta-lactamases, and detection of blaTEM,blaSHV and blaCTX-M in Uyo, Nigeria

IntroductionInfections caused by multidrug-resistant (MDR) bacteria, extended spectrum β-lactamase (ESBL), metallo-β-lactamase (MBL) and AmpC-β-lactamase (AmpC-βL)-producers are increasing globally. This study identified bacteria in clinical and tap water samples and determined the prevalence of MDR, and β-lactamase enzymes and genes.MethodsIsolates were identified by the Vitek 2 (bioMérieux, France) automated system. Antibiotic resistance and screening for β-lactamase enzymes and genes was done using disc diffusion method and Vitek 2 automated system, CHROMagar-ESBL, combined double disc, inhibition-based method and multiplex polymerase chain reaction, respectively.ResultsThe Enterobacteriaceae isolates obtained were Escherichia coli, Klebsiella pneumoniae, Citrobacter freundii, Salmonella spp., Proteus mirabilis, Enterobacter aerogenes, Shigella sonnei, Proteus vulgaris, Enterobacter sakazakii, Klebsiella oxytoca, Citrobacter diversus, and Serratia liquefaciens. Of the 674 isolates from clinical samples, 36.5%, 28.5%, and 19.9% were ESBL, MBL, and AmpC-βL producers, respectively. A low prevalence of AmpC-βL and MBL producers were obtained, with no significant difference (p