An outbreak sustained by ST15 Klebsiella pneumoniae carrying 16S rRNA methyltransferases and blaNDM: evaluation of the global dissemination of these resistance determinants.

The spread of extremely-drug-resistant Klebsiella pneumoniae has become a major health threat worldwide. This is largely mediated by certain lineages, recognized as high-risk clones dispersed throughout the world. Analysis of an outbreak of nine ST15, NDM-1 metallo-β-lactamase-producing K. pneumoniae was performed. An IncC plasmid carrying the blaNDM-1 gene also carried the rare rmtC gene, encoding for 16S rRNA methyltransferases (16RMTases), conferring resistance to all aminoglycosides. The global spread of New Delhi metallo (NDM) variants and their association with the 16RMTases among K. pneumoniae complete genomes available in GenBank was studied, and a complete overview of the association of 16RMTases and NDM in K. pneumoniae genomics was produced. NDM is often associated with16RMTases, and both are spreading in K. pneumoniae, conferring resistance to all beta-lactams and aminoglycosides. This analysis suggests that aminoglycosides have a limited future as a second-line treatment against NDM-producing K. pneumoniae.