Diagnosis and Assessment
Preoperative Evaluation (Figure 1)
����Suspect PJI in patients with any of the following (B-III):
������ A sinus tract or persistent wound drainage over a joint prosthesis
������ Acute onset of prosthesis pain
������ Any chronic painful prosthesis at any time after prosthesis implantation,
particularly in the absence of a pain free interval in the first few years following
implantation
������ If there is a history of prior wound healing problems or superficial or deep
infection.
����Evaluation of the patient with a possible PJI should include a thorough
history and physical examination (C-III).
Items that should be obtained in the history include the type of prosthesis, date of
implantation, past surgeries on the joint, history of wound healing problems following
prosthesis implantation, remote infections, current clinical symptoms, drug allergies
and intolerances, comorbid conditions, prior and current microbiology results from
aspirations and surgeries, and antimicrobial therapy for the PJI including local
antimicrobial therapy (C-III).
����A sedimentation rate or C-reactive protein should be performed in
all patients with a suspected PJI when the diagnosis is not clinically
evident.
The combination of an abnormal sedimentation rate and C-reactive protein seems to
provide the best combination of sensitivity and specificity (A-III).
����A plain radiograph should be performed in all patients with suspected
PJI (A-III).
����A diagnostic arthrocentesis should be performed in all patients with a
suspected acute PJI unless:
������ the diagnosis is evident clinically
������ surgery is planned
������ antimicrobials can be safely withheld prior to surgery. (A-III)
����Arthrocentesis is also advised in patients with a chronic painful
prosthesis in whom there is an unexplained elevated sedimentation
rate or C-reactive protein (A-III) or in whom there is a clinical
suspicion of PJI.
������ Arthrocentesis may not be necessary if in this situation surgery is planned and the
result is not expected to alter management.
������ Synovial fluid analysis should include a total cell count and differential leukocyte
count, as well as culture for aerobic and anaerobic organisms (A-III).
������ A crystal analysis can also be performed if clinically indicated.
����In PJI where the patient is medically stable, withholding antimicrobial
therapy for at least two weeks prior to collecting synovial fluid for
culture increases the likelihood of recovering an organism (B-III).
1
