Is Xpert MRSA/SA SSTI real-time PCR a reliable tool for fast detection of methicillin-resistant coagulase-negative staphylococci in periprosthetic joint infections?

Diagn Microbiol Infect Dis. 2015 Sep;83(1):59-62. doi: 10.1016/j.diagmicrobio.2015.04.009. Epub 2015 May 7.

Abstract

Periprosthetic joint infections (PJIs) are frequently caused by methicillin-resistant coagulase-negative staphylococci (CoNS). Cultures remain the gold standard but often require a few days. Thus, a rapid test could be interesting to guide antibiotic strategy earlier. The purpose of this study was to evaluate the performances of RT-PCR Xpert® MRSA/SA technique for the detection of methicillin-resistant CoNS (MRCoNS) from deep samples in patients with PJIs. RT-PCR was tested on 72 samples. Sensitivity, specificity, positive predictive value, and negative predictive value of RT-PCR method were 0.36, 0.98, 0.90, and 0.74, respectively. Although RT-PCR may allow early microbial diagnosis of PJI due to Staphylococcus aureus (MSSA and MRSA), the low sensitivity and the high cost of this method to detect MRCoNS could limit its use in this field.

Keywords: Coagulase-negative staphylococci; PCR GenXpert; Periprosthetic joint infection.

Publication types

  • Evaluation Study

MeSH terms

  • Arthritis / diagnosis*
  • Arthritis / microbiology
  • Coagulase / deficiency
  • Humans
  • Methicillin Resistance*
  • Predictive Value of Tests
  • Prosthesis-Related Infections / diagnosis*
  • Prosthesis-Related Infections / microbiology
  • Real-Time Polymerase Chain Reaction / methods*
  • Retrospective Studies
  • Sensitivity and Specificity
  • Staphylococcal Infections / diagnosis*
  • Staphylococcal Infections / microbiology
  • Staphylococcus / enzymology
  • Staphylococcus / isolation & purification*

Substances

  • Coagulase