Definitions
Prosthetic joint infection (PJI) is an infrequent but serious complication of joint arthroplasty. PJI affect approximately 2% of total knee arthroplasty (TKA) and total hip arthroplasty (THA).
Types
- Early/Post-operative
- Late/Haematogenous
- Chronic
Definitions
Clinical:
- Sinus tract communicating with prosthesis
- Purulence surrounding prosthetic joint
Microbiological:
- Presence of 2 phenotypically indistinguishable organisms recovered from joint tissue/fluid specimens OR single virulent organism (e.g. S. aureus)
Histological:
- Acute inflammation on histopathological examination of periprosthetic tissue
Diagnosis
- Dx and Mx PJI dependent on microbiological sampling
- Separate instruments should be used to minimize contamination. Each tissue sampled should be transferred to a separate sterile container and labeled
- Recommended sample sites: capsular tissue, acetabular membrane (for THA), femoral membrane, tibial membrane (for TKA), other tissue (i.e. granulation tissue)
- ID of the causative organism may be optimized by the addition of enrichment cultures (i.e. blood culture specimen bottles/other enrichment media)
- For chronic PJI, consider peri-prosthetic biopsy or aspirate in advance of surgery
Antimicrobial therapy
- In general, systemically stable patients with chronic PJI should not receive any antibiotics for 2 weeks prior to operative sampling to optimize culture yield
- Surgical prophylaxis should not be given in theatre
- I.D. should be consulted for all patients with PJI
Preoperative care
Treatment AFTER sampling
Empiric therapy
- Early active antimicrobial therapy is associated better outcomes in PJI treated with debridement, antibiotics and implant retention (DAIR)
- All patients should receive empiric coverage for gram-positive and gram-negative organisms after sampling
- Gram-negative cover (i.e. Piperacillin/tazobactam or ceftriaxone as per above algorithms) should be continued for 48 hours after surgery. If no gram-negative organisms are grown at 48 hours, gram-negative cover can be discontinued
- Gram-positive cover (i.e. vancomycin) should be continued for 7 days until reviewed by ID or until results from sampling are available
- For patients with chronic PJI and a known organism, empiric regimen should include an antibiotic with activity against that organism
Local antimicrobial therapy
- There is evidence that use of antibiotic-loaded spacers improves outcomes in PJI
- Surgical team should ensure that an antibiotic with appropriate cover for the isolated organism is used. Consult I.D. for further guidance
Monitoring
- All patients receiving antimicrobial therapy as an inpatient should have twice weekly FBC, renal/liver profile, CRP
- Drug specific monitoring:
- Vancomycin – twice weekly trough levels if within range (refer to Vancomycin dosing and monitoring on nchd.ie)
- Daptomycin – weekly CK levels and to hold statins
- Gentamicin – daily trough level prior to antibiotic admin.
- Rifampicin – Pharmacy review due to multiple drug-drug interactions. Weekly LFTs
- Antifungals – weekly renal/liver profiles
Micro interpretation
- A positive microbiology result is the isolate of either:
- At least 2 phenotypically indistinguishable organisms (e.g. S. hominis)
- 1 virulent organism (e.g. S. aureus)
- Surgical team should ensure that an antibiotic with appropriate cover for the isolated organism is used. Consult Infectious Diseases for further guidance
Links
- Peri-prosthetic joint infection guideline (CUH): Dr Matthew Blair 2024