Genotypic profiling of virulence factors and serogroup variability in septicemia-associated Escherichia coli
DOI:
https://doi.org/10.31185/bsj.Vol21.Iss36.1539Keywords:
Escherichia coli, Sepsis, Bloodstream infection, Virulence factors, O-serogroupsAbstract
Escherichia coli (E.coli) is a leading cause of bloodstream infection (BSI) and sepsis globally. For E. coli, the O-serogroups and VF genes in septicaemia isolates were determined and correlated with the severity of sepsis and outcome among patients. Eighty-six non-repetitive E. coli isolates were obtained from blood cultures of the septic cases, who were aged between 20 and 70 years. Haemolytic genes were detected by multiplex PCR, serogroups were classified, and the clinical and microbiologic factors related to the severity of illness and mortality were statistically analysed. High virulence genotypes having toxin genes, serum resistance genes, predominant dominant O-serogroups (O25/O6/O15), and multidrug resistant profiles were significantly associated with severe sepsis and in-hospital mortality. In this report, we add to the contribution of high-virulence genotypes (≥4 virulence genes, including toxin and complement resistance determinant) for E. coli septicaemia and predominant O-serogroups (O25/O6/O15) as independent predictors of severe clinical outcome, as well as in-hospital death rates, even more than multi-resistance phenotypes. These data provide evidence for integrating molecular virulence profiling in clinical risk stratification and antimicrobial stewardship programmes, particularly in resource-limited settings where focused intervention scales more effectively to impact outcomes.
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