- In June 2010 the American Academy of Orthopaedic Surgeons released its clinical practice guidelines to diagnose periprosthetic joint infection (PJI). These guidelines are based on a systematic review of the published literature. They have been developed to improve clinical practice. These guidelines are not designed to replace clinical judgement and each patient should be treated according to the individual situation.
- In the absence of reliable evidence about risk strati?cation of patients with a potential periprosthetic joint infection, it is the opinion of the work group that testing strategies be planned according to whether there is a higher or lower probability that a patient has a hip or knee periprosthetic infection.
Strength of recommendation: Consensus
2. We recommend erythrocyte sedimentation rate and C-reactive protein testing for patients assessed for periprosthetic joint infection.
Strength of recommendation: Strong
3. We recommend joint aspiration of patients being assessed for periprosthetic knee infections who have abnormal erythrocyte sedimentation rate and/or C-reactive protein results. We recommend that the aspirated ?uid be sent for microbiological culture, synovial ?uid white blood cell count and differential.
Strength of recommendation: Strong
4. We recommend a selective approach to aspiration of the hip based on the patient’s probability of periprosthetic joint infection and the results of the erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP). We recommend that the aspirated ?uid be sent for microbiological culture, synovial ?uid white blood cell count and differential.
Strength of recommendation: Strong
Table 1.
Probability of infection
|
ESR and CRP results
|
Planned reoperation status
|
Recommended test
|
Higher
|
++ OR +–
|
Planned or not planned
|
Aspiration
|
Lower
|
++ OR +–
|
Planned
|
Aspiration or frozen section
|
Lower
|
+ +
|
Not planned
|
Aspiration
|
Lower
|
+ –
|
Not planned
|
Please see recommendation 6
|
Higher or lower
|
– –
|
Planned or not planned
|
No further testing
|
Key for ESR and CRP results
+ +: ESR and CRP test results are abnormal
+ –: either ESR or CRP test result is abnormal
– –: ESR and CRP test results are normal
Aspiration is indicated for lower probability hip patients without planned reoperation only when both the ESR and CRP level are abnormal.
AAOS do not recommend that higher or lower probability patients with normal ESR and CRP level have hip aspiration before planned reoperation.
5. We suggest a repeat hip aspiration when there is a discrepancy between the probability of periprosthetic joint infection and the initial aspiration culture result.
Strength of recommendation: Moderate
6. In the absence of reliable evidence, it is the opinion of the work group that patients judged to be at lower probability for periprosthetic hip infection and without planned reoperation who have abnormal erythrocyte sedimentation rates or abnormal C-reactive protein levels be re-evaluated within 3 months. We are unable to recommend speci?c diagnostic tests at the time of this follow-up.
Strength of recommendation: Consensus
7. In the absence of reliable evidence, it is the opinion of the work group that a repeat knee aspiration be performed when there is a discrepancy between the probability of periprosthetic joint infection and the initial aspiration culture result.
Strength of recommendation: Consensus
8. We suggest patients be off antibiotics for a minimum of 2 weeks prior to obtaining intra-articular culture.
Strength of recommendation: Moderate
9. Nuclear imaging (labeled leukocyte imaging combined with bone or bone marrow imaging, FDG-PET imaging, gallium imaging, or labeled leukocyte imaging) is an option in patients in whom a diagnosis of periprosthetic joint infection has not been established and are not scheduled for reoperation.
Strength of recommendation: Weak
10. We are unable to recommend for or against computed tomography (CT) or magnetic resonance imaging (MRI) as a diagnostic test for periprosthetic joint infection.
Strength of recommendation: Inconclusive
11. We recommend against the use of intraoperative Gram stain to rule out periprosthetic joint infection.
Strength of recommendation: Strong
12. We recommend the use of frozen sections of peri-implant tissues in patients who are undergoing reoperation for whom the diagnosis of periprosthetic joint infection has not been established or excluded.
Strength of recommendation: Strong
13. We recommend that multiple cultures be obtained at the time of reoperation in patients being assessed for periprosthetic joint infection.
Strength of recommendation: Strong
14. We recommend against initiating antibiotic treatment in patients with suspected periprosthetic joint infection until after cultures from the joint have been obtained.
Strength of recommendation: Strong
15. We suggest that prophylactic preoperative antibiotics not be withheld in patients at lower probability for periprosthetic joint infection and those with an established diagnosis of periprosthetic joint infection who are undergoing reoperation.