NDM-5-producing Klebsiella pneumoniae ST258 in a university hospital in Argentina.

Background: A drastic increase in carbapenem resistance among Klebsiella pneumoniae isolates occurred during the period 2019-22. Three epidemiological changes could be evidenced: (i) NDM became the predominant carbapenemase; (ii) NDM-5 replaced NDM-1; and (iii) the emergence of NDM-producing K. pneumoniae ST258 (NDM-KpST258).

Clinical, microbiological, and genetic characteristics of heteroresistant vancomycin-intermediate Staphylococcus aureus bacteremia in a teaching hospital.

The emergence of vancomycin intermediate Staphylococcus aureus (VISA) and heterogeneous VISA (hVISA) is of major concern worldwide. Our objective was to investigate the prevalence, phenotypic and molecular features of hVISA strains isolated from bacteremic patients and to determine the clinical significance of the hVISA phenotype in patients with bacteremia. A total of 104 S.