Therapeutic outcome of spinal implant infections caused by Staphylococcus aureus: A retrospective observational study

Medicine (Baltimore). 2018 Oct;97(40):e12629. doi: 10.1097/MD.0000000000012629.

Abstract

Spinal implant infection is a rare but significant complication of spinal fusion surgery, and the most common pathogen is Staphylococcus aureus. It is difficult to treat due to this pathogen's biofilm-forming ability and antibiotic resistance. We evaluated the therapeutic outcome of treatments for S aureus spinal implant infections. We retrospectively reviewed all patients with S aureus spinal implant infections at 11 tertiary-care hospitals over a 9-year period. Parameters predictive of treatment failure and recurrence were analyzed by Cox regression. Of the 102 patients with infections, 76 (75%) were caused by methicillin-resistant S aureus (MRSA) and 51 (50%) were late-onset infections. In all, 83 (81%) patients were managed by debridement, antibiotics, and implant retention (DAIR) and 19 (19%) had their implants removed. The median duration of all antibiotic therapies was 52 days. During a median follow-up period of 32 months, treatment failure occurred in 37 (36%) cases. The median time to treatment failure was 113 days, being <1 year in 30 (81%) patients. DAIR (adjusted hazard ratio [aHR], 6.27; P = .01) and MRSA infection (aHR, 4.07; P = .009) were independently associated with treatment failure. Rifampin-based combination treatments exhibited independent protective effects on recurrence (aHR, 0.23; P = .02). In conclusion, among patients with S aureus spinal implant infections, MRSA and DAIR were independent risk factors for treatment failure, and these risk factors were present in the majority of patients. In this difficult-to-treat population, the overall treatment failure rate was 36%; rifampin may improve the outcomes of patients with S aureus spinal implant infections.

Publication types

  • Multicenter Study
  • Observational Study

MeSH terms

  • Aged
  • Anti-Bacterial Agents / therapeutic use
  • Debridement / methods
  • Female
  • Humans
  • Male
  • Methicillin-Resistant Staphylococcus aureus
  • Middle Aged
  • Prosthesis-Related Infections / epidemiology*
  • Prosthesis-Related Infections / therapy
  • Retrospective Studies
  • Rifampin
  • Risk Factors
  • Spinal Fusion / adverse effects*
  • Spinal Fusion / statistics & numerical data*
  • Staphylococcal Infections / epidemiology*
  • Staphylococcal Infections / therapy
  • Staphylococcus aureus
  • Tertiary Care Centers

Substances

  • Anti-Bacterial Agents
  • Rifampin