Antibiotic Resistance and Virulence Factors of Extended-Spectrum Beta-Lactamase-Producing Klebsiella Pneumoniae Involved in Healthcare-Associated Infections in Dakar, Senegal

Author(s): Issa NDIAYE, Bissoume Sambe BA, Farma THIAM, Mouhamadou Moustapha BOYE, Ousmane SOW, Abdoulaye CISSÉ, Babacar NDIAYE, Thierno Abdoulaye DIALLO, Cheikh FALL, Yakhya DIEYE, Baidy DIÈYE, Assane DIENG, Amadou DIOP, Guillaume CONSTANTIN DE MAGNY and Abdoulaye SECK

Background: Virulent and resistant Klebsiella pneumoniae strains are considered as one of the most significant causes of healthcare-associated infections (HAIs). The aim of this study was to investigate the phenotypic and genotypic factors of antibiotic resistance and virulence factors of ESBL K. pneumoniae strains isolated from healthcare-associated infections (HAIs) in Dakar, Senegal.

Methods: Twenty-eight strains of K. pneumoniae isolated from HAIs were collected from 2018 to 2021 in 2 main hospitals in Dakar. Antibiotic susceptibility and molecular characterization were studied using disk diffusion by the Kirby-Bauer method and PCR, respectively. Virulence factors were also determined by PCR.

Results: These ESBL K. pneumoniae isolates showed high resistance to antibiotics such as β-lactams, aminoglycosides, cyclins, fluoroquinolones and trimethoprim-sulfamethoxazole. Among these strains, ten (10) were resistant to carbapenem and cefoxitin (17.8%, n=5), chloramphenicol (25%, n=7) and fosfomycin (28.5%, n=8) considered as the most active antibiotics against ESBL-KP isolates. Eighteen (18) strains were considered as MDR and ten (10) strains as XDR. For the genes associated to phenotypic resistance, β-lactams resistance was conferred through blaSHV (24/28), blaTEM (20/28) and mainly by blaCTX-M. All strains carried the blaCTX-M15 gene. OXA-48 (6/28) gene was found responsible for carbapenem resistance and other genes like IMP, VIM, NDM, OXA-23 were not detected. Plasmids-mediated resistance genes qnrB (16/28), qnrS (11/28) and aac(6’)-Ib (21/28), were mostly responsible for resistance to fluoroquinolones and aminoglycosides. Also 3 of 6 virulence genes searched that are the most associated to the pathogenicity of Klebsiella pneumoniae were found on these strains with uge (19/28), mrKD (21/28) and fyuA (13/28).

Conclusion: The ESBL K. pneumoniae strains isolated in this study showed a high prevalence of antibiotic resistance and virulence genes The combination of these factors poses a potential risk for infections that could be highly virulent and difficult to treat. These findings demonstrated the importance of closely monitoring the resistance patterns of K. pneumoniae in hospitals seetings and emphasize the need to monitor effective antibiotic treatments for K. pneumoniae infections. Aditionnally, the scarcity of available data on HAIs, especially the prevalence of Multidrug resistance bacteria and virulence factors associated with these HAIs in Senegal, further emphasizes the significance of implementing surveillance programs to better know their prevalence, impact on patient health and on length of hospital stays.