Management of Suspected Prosthetic Joint Infection
Diagnostic Approach
- The American College of Physicians and the Infectious Diseases Society of America recommend performing diagnostic arthrocentesis immediately unless surgery is already planned and antimicrobials can be safely withheld beforehand, with synovial fluid analysis including total cell count and differential leukocyte count, aerobic and anaerobic cultures, and consideration of crystal analysis if clinically indicated 1, 2, 3, 4
- Plain radiographs of both knees should be obtained to evaluate for prosthetic loosening, osteolysis, or other radiographic signs of infection 1, 2, 5
- Blood cultures for aerobic and anaerobic organisms should be drawn given the acute presentation and systemic inflammatory response 1, 2, 6
Surgical Management
- The Infectious Diseases Society of America recommends that Debridement and Implant Retention (DAIR) may be considered only if the duration of symptoms is less than 3 weeks, the prosthesis is well-fixed on imaging, there is an absence of sinus tract, and the organism is susceptible to oral antimicrobial agents with biofilm activity 4, 6
- Prosthesis removal via either one-stage or two-stage exchange is required if DAIR criteria are not met, with two-stage exchange being the gold standard in North America for established PJI 6, 4, 8
- During two-stage exchange, 3-6 intraoperative tissue samples should be obtained for aerobic and anaerobic culture 1, 6, 5
Antimicrobial Therapy
- The Infectious Diseases Society of America recommends withholding empiric antimicrobials until adequate cultures are obtained if the patient is medically stable, and then initiating pathogen-specific IV antimicrobial therapy based on culture results and susceptibilities 1, 2, 7, 9, 10
- The duration of antimicrobial therapy should be 4-6 weeks of IV or highly bioavailable oral therapy following definitive surgical debridement 9, 10