Uncovering Carbapenem Resistance: A Molecular Look at Klebsiella pneumoniae in Clinical Samples

The rise of multidrug-resistant (MDR) Klebsiella pneumoniae has greatly complicated the management of infections caused by this pathogen. This study aimed to assess the antimicrobial resistance patterns and to detect the presence of β-lactamase genes in both MDR and non-MDR K. pneumoniae isolates obtained from a variety of clinical specimens. A total of 50 K. pneumoniae isolates were collected and identified using standard microbiological techniques. Antimicrobial susceptibility testing was performed using the Kirby-Bauer disk diffusion method. Phenotypic detection of extended-spectrum β-lactamases (ESBLs), metallo-β-lactamases (MBLs), and carbapenemases was carried out via the double-disk synergy test, combined disk test, and modified Hodge test, respectively. Detection of resistance and virulence genes at the molecular level was conducted using polymerase chain reaction (PCR). Multidrug resistance was observed in 50% of the isolates, with high levels of resistance to β-lactam antibiotics, carbapenems, ciprofloxacin, piperacillin, and tazobactam. Notably, 28% of the isolates also exhibited resistance to colistin. ESBL was identified phenotypically in 30% of the isolates. NDM-1 (12%), NDM-5 (2%), VIM (4%), and KPC (8%) were detected among β-lactamase genes. These findings indicate a high prevalence of MDR K. pneumoniae in Bangladesh, posing a serious challenge for infection control and treatment strategies in healthcare settings.