Study of extended-spectrum beta-lactamases and AmpC beta-lactamases producing Klebsiella from clinical samples in tertiary care hospital of Punjab

BACKGROUND Klebsiella species are important opportunistic pathogens responsible for various hospital- and community-acquired infections. The rise of multidrug-resistant strains, especially those producing extended-spectrum beta-lactamases (ESBL) and AmpC beta-lactamases, poses a major challenge to effective antimicrobial therapy and infection control. AIM To determine the antimicrobial susceptibility pattern of Klebsiella isolates and to detect the presence of ESBL and AmpC beta-lactamases. METHODS A one-year cross-sectional study was conducted on 920 Gram-negative isolates, from which 130 non-repetitive Klebsiella isolates (14.13%) were selected. Antimicrobial susceptibility testing was performed, and ESBL and AmpC production were identified using standard phenotypic confirmatory methods. RESULTS Among 130 Klebsiella isolates, Klebsiella pneumoniae was the predominant species (n = 92, 70.76%). Most isolates were obtained from patients aged 45-60 years (n = 33, 25.38%) and from pus samples (n = 55, 42.3%), with the highest frequency from surgical departments (n = 36, 27.7%). Among the tested antibiotics, gentamicin showed the greatest susceptibility (n = 81, 62.3%). ESBL production was detected in 77 isolates (59.2%), while 62 isolates (47.69%) produced AmpC beta-lactamases. Co-production of ESBL and AmpC was found in 35 isolates (26.92%). CONCLUSION Klebsiella species are significant nosocomial and opportunistic pathogens characterized by high multidrug resistance, often through the production of extended-spectrum and AmpC beta-lactamases. Surveillance, confirmatory testing, and infection control guide antibiotic use and prevent spread.