High-Resolution Genomic Profiling of Carbapenem-Resistant Klebsiella pneumoniae Isolates: A Multicentric Retrospective Indian Study

Abstract

summaryWe report insights into genome sequences of Indian K. pneumoniae isolates, highlighting the presence of high-risk international clones and genetic pools different from those predominating in other regions. Identification of multidrug-resistant and hypervirulent K. pneumoniae elicits public health concerns. BackgroundCarbapenem-resistant Klebsiella pneumoniae (CRKP) is a threat to public health in India due to its high dissemination, mortality, and limited treatment options. Its genomic variability is reflected in the diversity of sequence types, virulence factors, and antimicrobial resistance (AMR) mechanisms. This study aims to characterize the clonal relationships and genetic mechanisms of resistance and virulence in CRKP isolates in India. Materials and MethodsWe characterized 344 retrospective K. pneumoniae clinical isolates collected from 8 centers across India collected in 2013-2019. Susceptibility to antibiotics was tested with VITEK 2. Capsular types, MLST, virulence genes, AMR determinants, plasmid replicon types, and a single-nucleotide polymorphism (SNP) phylogeny were inferred from their whole genome sequences. ResultsPhylogenetic analysis of the 325 Klebsiella isolates that passed QC revealed 3 groups: K. pneumoniae sensu stricto (n=307), K. quasipneumoniae (n=17), and K. varicolla (n=1). Sequencing and capsular diversity analysis of the 307 K. pneumoniae sensu stricto isolates revealed 28 sequence types, 26 K-locus types, and 11 O-locus types, with ST231, KL51, and O1V2 being predominant. blaOXA-48-like and blaNDM-1/5 were present in 73.2% and 24.4% of isolates respectively. The major plasmid replicon types associated with carbapenase genes were IncF (51.0%), and Col group (35.0%). ConclusionOur study documents for the first time the genetic diversity of K- and O-antigens circulating in India. The results demonstrate the practical applicability of genomic surveillance and its utility in tracking the population dynamics of CRKP. It alerts us to the urgency for longitudinal surveillance of these virulent and transmissible lineages. FundingThis work was supported by Official Development Assistance (ODA) funding from the National Institute of Health Research [grant number 16_136_111]. This research was commissioned by the National Institute of Health Research using Official Development Assistance (ODA) funding. The views expressed in this publication are those of the authors and not necessarily those of the NHS, the National Institute for Health Research or the Department of Health. Conflict of InterestThe authors: No reported conflicts of interest. All authors have submitted the ICMJE Form for Disclosure of Potential Conflicts of Interest.