Positive Blood Cultures in Periprosthetic Joint Infection Decrease Rate of Treatment Success

Area of Science:

• Orthopedic Surgery
• Infectious Diseases
• Medical Diagnostics

Background:

• Periprosthetic joint infection (PJI) diagnosis often includes blood cultures, but their role in treatment outcomes remains unclear.
• Current diagnostic criteria for PJI do not incorporate blood culture results.

Purpose of the Study:

• To evaluate the utilization of blood cultures during PJI diagnosis.
• To determine if positive blood cultures impact the success of PJI treatment.

Main Methods:

• A retrospective review of 320 patients with hip and knee PJIs treated between 2006 and 2013.
• Treatment success was assessed using the Delphi criteria with a minimum 12-month follow-up.
• Logistic regression analysis identified factors associated with treatment success.

Main Results:

• Blood cultures were obtained in 53.1% of PJI cases, with 86.0% concordance between blood and operative cultures for organism identification.
• Positive blood cultures correlated with higher synovial white blood cell counts and serum C-reactive protein levels.
• Patients with positive blood cultures had significantly lower treatment success rates (65.1%) compared to those with negative (85.0%) or no blood cultures (82.7%).

Conclusions:

• Positive blood cultures at the time of PJI diagnosis are associated with decreased treatment success.
• Further prospective research is necessary to define the precise role of blood cultures in PJI workup and optimize treatment strategies.