PREVALENCE AND MOLECULAR CHARACTERIZATION OF <i>BLA<sup>TEM</sup></i>, <i>BLA<sup>SHV</sup></i> AND <i>BLA<sup>CTX-M</sup></i><sup> </sup>GENES IN ESBL-PRODUCING <i>Escherichia coli</i> AND <i>Klebsiella pneumoniae</i> ISOLATED FROM INTENSIVE CARE UNIT PATIENTS
Abstract
The rise and spread of antimicrobial resistance (AMR) not only significantly hinder the effective treatment of infectious diseases, but also lead to prolonged illness, treatment failures, and increased mortality. In intensive care units (ICUs), extended-spectrum β-lactamase (ESBL)-producing bacteria, such as Escherichia coli (E. coli) and Klebsiella pneumoniae (K. pneumoniae), are among the most concerning multidrug-resistant organisms (MDROs. This research was conducted to find out the causative agents of ICU infections, identify their profiles of antimicrobial resistance, and assess associated virulence factors. Discrepancies were found in bacterial identification by molecular analysis using 16S rRNA sequencing compared to the Vitek2 system. More than half (50%) carried all three ESBL genes, while the prevalence of blaSHV + blaCTX-M carriers were the lowest. Isolates of E. coli from the study were not found to be salmon single ESBL genes (blaSHV, blaCTX, or blaTEM), only 5.26% of K. pneumoniae isolates carried blaTEM among them. Most of the strains had moderate to high biofilm-forming ability, which is the key to their MDR. In other words, ICU patients are vulnerable to colonization and infection with MDR pathogens, and still, E. coli and K. pneumoniae are the major threats that are linked to the resistance mechanisms and virulence factors of these pathogens.
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References
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