quinolone resistance in biofilm-forming klebsiellapneumoniae-related catheter-associated urinary tract infections: aneglected problem

Background: klebsiella pneumoniaeis a bacterium that commonly causes urinary tract infections (utis) in hospital settings. the widespread and improper usage of quinolones has increased the resistance rates against these broad-spectrum antibiotics. objectives: this study aimed to examine the connection between the ability to form biofilms and fluoroquinolone resistance in k. pneumoniaeisolated from catheter-associated utis. methods: a total of 110 nonduplicative k. pneumoniae-related catheter-associated utis were isolated from three large educational hospitals in babol, north of iran. the minimal inhibitory concentration (mic) of ciprofloxacin was calculated for each detected isolate using the agar dilution procedure. biofilm production was investigated by a 96-well flat-bottom microtiter plate. the prevalence of gyra, parc, qnra, qnrs, acc (6’)-ib-cr, qepa, qnrb, oqxa,and oqxbgenes was evaluated using polymerase chain reaction (pcr). results: overall, 28.2% of the strains were resistant to imipenem and considered carbapenem-resistant k. pneumoniae(crkp). ciprofloxacin resistance was observed in 66.4%. moreover, 70% of the isolates produced biofilm. biofilm production was significantly higher in ciprofloxacin-resistant compared to ciprofloxacin-susceptible strains (p-value < 0.05). molecular distribution of resistance genes in the 68-fluoroquinolone resistance-kp strains showed that the prevalence of gyra, parc, qnra, qnrs, acc (6’)-ib-cr, qepa, qnrb, oqxa,and oqxbgenes was 39.7%, 42.6%, 5.9%, 54.4%, 69.1%, 94.1%, 41.2%, 69.1%, and 83.8%, respectively. conclusions: our study highlights the high prevalence of plasmid-mediated quinolone resistance genes in clinical samples of k. pneumoniaein the studied region, which is alarming given the possibility of the spread of these pathogens and the few treatments available for infections brought on by multidrug-resistant strains. moreover, the study characterizes particular mutations in the parcand gyragenes that cause quinolone resistance.