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AmpC β-Lactamase Variable Expression in Common Multidrug-Resistant Nosocomial Bacterial Pathogens from a Tertiary
Aliaa Ali El Shamy1, Zainab Zakaria2, Mahmoud M Tolba3
1Microbiology and Immunology Department, Faculty of Pharmacy, Heliopolis University, Cairo, Egypt.
Abstract:
The emergence of AmpC (pAmpC) β-lactamases conferring resistance to the third-generation cephalosporins has become a major clinical concern worldwide. In this study, we aimed to evaluate the expression of AmpC β-lactamase encoding gene among the pathogenic Gram-positive and Gram-negative resistant bacteria screened from clinical samples of Egyptian patients enrolled into El-Qasr El-Ainy Tertiary Hospital in Cairo, Egypt. A total of 153 bacterial isolates of the species Pseudomonas aeruginosa, Klebsiella pneumoniae, and Enterococcus faecium were isolated from patients diagnosed with urinary tract infection (UTI), respiratory tract infection (RTI), and wound infections. The total number of E. faecium isolates was 53, comprising 29 urine isolates, 5 sputum isolates, and 19 wound swab isolates, whereas the total number of P. aeruginosa isolates was 49, comprising 27 urine isolates, 7 sputum isolates, and 15 wound swab isolates, and that of the K. pneumoniae isolates was 51, comprising 20 urine isolates, 25 sputum isolates, and 6 wound swab isolates. Our results indicated that there is no significant difference in the expression of AmpC β-lactamase gene among the tested bacterial species with respect to the type of infection and/or clinical specimen. However, the expression patterns of AmpC β-lactamase gene markedly differed according to the antibacterial resistance characteristics of the tested isolates.
Insights
AmpC beta-lactamase gene expression was evaluated in resistant bacteria from Egyptian patients. Expression levels did not significantly differ by infection type but varied with antibacterial resistance profiles.
Area of Science:
- Microbiology
- Clinical Medicine
- Molecular Biology
Background:
- AmpC beta-lactamases (pAmpC) confer resistance to third-generation cephalosporins, posing a global clinical challenge.
- Understanding AmpC beta-lactamase gene expression is crucial for combating antimicrobial resistance.
Purpose of the Study:
- To assess AmpC beta-lactamase gene expression in pathogenic bacteria from Egyptian patients.
- To investigate the relationship between gene expression, infection type, and antibacterial resistance.
Main Methods:
- Bacterial isolates (Pseudomonas aeruginosa, Klebsiella pneumoniae, Enterococcus faecium) were obtained from clinical samples (urine, sputum, wound).
- AmpC beta-lactamase encoding gene expression was analyzed across different bacterial species and infection types.
- Gene expression patterns were correlated with the isolates' antibacterial resistance characteristics.
Main Results:
- No significant difference in AmpC beta-lactamase gene expression was observed among the tested bacterial species concerning infection type or clinical specimen.
- However, significant variations in AmpC beta-lactamase gene expression were noted based on the antibacterial resistance profiles of the isolates.
Conclusions:
- Antibacterial resistance patterns are a key determinant of AmpC beta-lactamase gene expression in these clinical isolates.
- Further research into resistance mechanisms can inform strategies against cephalosporin-resistant infections.
