Oral Therapy, Microbiological Findings, and Comorbidity Influence the Outcome of Prosthetic Joint Infections Undergoing 2-Stage Exchange

J Arthroplasty. 2017 Jul;32(7):2239-2243. doi: 10.1016/j.arth.2017.02.057. Epub 2017 Mar 10.

Abstract

Background: The aim of the present study was to investigate potential predictive factors of an unfavorable outcome in patients with prosthetic joint infection (PJI) undergoing 2-stage exchange.

Methods: Patients with PJI undergoing 2-stage exchange and observed over a 5-year period (2009-2013) were included. Cure was defined by the disappearance of infection after a 96-week follow-up period. Statistical analysis was performed using the Mann-Whitney U test, the Fisher exact test, and the multivariate analysis.

Results: One-hundred twenty-two patients with PJI were included (median age, 69 years [range, 36-80 years]; 48% males, 47 hip PJI, and 75 knee PJI). Known comorbidities related to an increased risk of infection were reported in 43 patients (35%). Microbiological definition was obtained in 101 (83%) patients, and Staphylococcus aureus was isolated in 44 (36%) patients. Coagulase-negative staphylococci were isolated in 41 (34%) patients. A favorable outcome was obtained in 102 of 122 patients (84%). After univariate analysis, bacterial growth from operative specimens (P = .007), growth of Gram-positive bacteria (P < .001), use of oral therapy (P = .01), and absence of known comorbidities (P = .02) were associated with favorable outcome. Administration of rifampin (P = .99) and results of blood analysis were not predictive of outcome. After multivariate analysis was applied, infection sustained by Gram-positive bacteria, administration of oral antibiotics, and absence of known comorbidities frequently resulted in favorable outcome.

Conclusion: A favorable outcome in patients with PJI undergoing 2-stage procedure was associated with an infection sustained by Gram-positive bacteria, absence of known comorbidities, and administration of oral therapy. Therefore, failure rate can be reduced with appropriate treatment choices.

Keywords: 2-stage exchange; diagnosis; infection; prosthetic joint infections; treatment.

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Anti-Bacterial Agents / therapeutic use*
  • Arthroplasty, Replacement, Hip / adverse effects
  • Arthroplasty, Replacement, Hip / statistics & numerical data*
  • Arthroplasty, Replacement, Knee / adverse effects
  • Arthroplasty, Replacement, Knee / statistics & numerical data*
  • Comorbidity
  • Female
  • Hip Prosthesis / adverse effects
  • Hip Prosthesis / microbiology
  • Humans
  • Italy / epidemiology
  • Joint Diseases
  • Knee Joint
  • Knee Prosthesis / adverse effects
  • Knee Prosthesis / microbiology
  • Male
  • Methicillin-Resistant Staphylococcus aureus / isolation & purification
  • Middle Aged
  • Prostheses and Implants
  • Prosthesis-Related Infections / drug therapy
  • Prosthesis-Related Infections / epidemiology
  • Prosthesis-Related Infections / microbiology*
  • Prosthesis-Related Infections / surgery
  • Reoperation / methods
  • Reoperation / statistics & numerical data*
  • Retrospective Studies
  • Rifampin / therapeutic use
  • Staphylococcal Infections / drug therapy
  • Staphylococcus aureus
  • Treatment Outcome

Substances

  • Anti-Bacterial Agents
  • Rifampin