Phenotypic and genomic characterization of a small colony variant of Klebsiella pneumoniae isolated from urine of a prostate cancer case

Indian J Med Microbiol. 2024 Sep-Oct:51:100664. doi: 10.1016/j.ijmmb.2024.100664. Epub 2024 Jul 16.

Abstract

Small colony variants (SCVs) in Klebsiella pneumoniae are rare and understudied. We report an SCV of Klebsiella pneumoniae isolated from the urine of a prostate cancer patient undergoing prolonged radiotherapy. The strain was non-lactose fermenting, non-mucoid, slow-growing, multi-drug resistant, and showed atypical biochemical reactions and biofilm formation. On whole genome sequencing, it showed low-level virulence, sequence type 231 and gene CTX-M-15. Three major porins OmpK35, OmpK36 and OmpK37 were found. SCVs pose challenges like difficulties in identification, altered metabolism, and increased biofilm formation, which contribute to persistent infections. Radiotherapy and chemotherapy may have led to the formation of the SCV phenotype.

Keywords: Bacteriuria in immunocompromised patients; Klebsiella pneumoniae; ST231; Small colony variant.

Publication types

  • Case Reports

MeSH terms

  • Biofilms / growth & development
  • Drug Resistance, Multiple, Bacterial / genetics
  • Genome, Bacterial
  • Humans
  • Klebsiella Infections* / microbiology
  • Klebsiella Infections* / urine
  • Klebsiella pneumoniae* / genetics
  • Klebsiella pneumoniae* / isolation & purification
  • Klebsiella pneumoniae* / pathogenicity
  • Male
  • Phenotype
  • Prostatic Neoplasms* / microbiology
  • Urine / microbiology
  • Whole Genome Sequencing