Molecular characteristics of Staphylococcus aureus associated prosthetic joint infections after hip fractures treated with hemiarthroplasty: a retrospective genome-wide association study

Sci Rep. 2020 Oct 6;10(1):16553. doi: 10.1038/s41598-020-73736-3.

Abstract

A retrospective study of Staphylococcus aureus isolates from orthopaedic patients treated between 2000 and 2017 at Akershus University Hospital, Norway was performed using a genome-wide association approach. The aim was to characterize and investigate molecular characteristics unique to S. aureus isolates from HHA associated prosthetic joint infections and potentially explain the HHA patients' elevated 1-year mortality compared to a non-HHA group. The comparison group consisted of patients with non-HHA lower-extremity implant-related S. aureus infections. S. aureus isolates from diagnostic patient samples were whole-genome sequenced. Univariate and multivariate analyses were performed to detect group-associated genetic signatures. A total of 62 HHA patients and 73 non-HHA patients were included. Median age (81 years vs. 74 years; p < 0.001) and 1-year mortality (44% vs. 15%, p < 0.001) were higher in the HHA group. A total of 20 clonal clusters (CCs) were identified; 75% of the isolates consisted of CC45, CC30, CC5, CC15, and CC1. Analyses of core and accessory genome content, including virulence, resistance genes, and k-mer analysis revealed few group-associated variants, none of which could explain the elevated 1-year mortality in HHA patients. Our findings support the premise that all S. aureus can cause invasive infections given the opportunity.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Aged, 80 and over
  • Female
  • Genome-Wide Association Study
  • Hemiarthroplasty / adverse effects*
  • Hemiarthroplasty / methods*
  • Hemiarthroplasty / mortality
  • Hip Fractures / mortality
  • Hip Fractures / surgery*
  • Hip Prosthesis / adverse effects*
  • Hip Prosthesis / microbiology*
  • Humans
  • Male
  • Norway
  • Opportunistic Infections / complications
  • Opportunistic Infections / microbiology
  • Prosthesis-Related Infections / complications
  • Prosthesis-Related Infections / microbiology*
  • Retrospective Studies
  • Staphylococcal Infections / complications
  • Staphylococcal Infections / drug therapy
  • Staphylococcal Infections / microbiology*
  • Staphylococcus aureus / genetics*
  • Staphylococcus aureus / isolation & purification
  • Staphylococcus aureus / pathogenicity
  • Time Factors
  • Virulence