Virulence factors and intraclonal diversity of ESBL and carbapenemase-producing Klebsiella pneumoniae and Escherichia coli clinical isolates

Abstract

The association of advantage traits as resistance to antimicrobial agents and virulence is a complex scenario in the management of bacterial infections. Currently, high-risk clones or clonal complexes (HiRCC) has been responsible for the international dissemination of antibiotic resistant and/or virulence determinants, contributing to increases of morbidity and mortality worldwide. Besides, the time-consuming to detect a microorganism (and respectively adaptive advantage traits) have also contributes to delay in the accurate medical intervention. The global aim of this study is to characterize ESBL- and carbapenemase-producing K. pneumoniae and extraintestinal E. coli clones or clonal variants and/or plasmids with enhanced epidemicity and pathogenic potential circulating in the clinical setting in Brazil. For this purpose, we will study bacteria identified from hospitalized patients from four main hospitals in the northeast of São Paulo State in 2012. Characterization will include evaluation of phylogenetic relationships among isolates of same species, investigation of virulence potential (including virulence gene content and capsular types) and in vitro ability to biofilm formation. In addition, the ability of high-throughput tools for identification/discrimination of clones, antibiotic resistance and/or virulence genes will be investigated. The knowledge of the content of virulence factors and the pathogenic potential of ESBL- and carbapenemase-producing K. pneumoniae and E. coli contributes to a better understanding of bacterial colonization, pathogenicity and persistence abilities, thereby, it could provide tools for a higher efficacy in the management of bacterial infections by improving infection control measures and antibiotic therapy decisions. (AU)