Our goal is to increase diagnostic accuracy of synovial fluid testing in differentiating prosthetic joint infection(PJI) by more exhaustively studying simple and inexpensive biomarkers. For that purpose, we sought to determine: 1) if synovial fluid C-reactive protein(CRP), alpha-2-macrogloblulin(A2M), procalcitonin and adenosine deaminase(ADA) concentrations are different between infected and aseptic cases; 2) performance and optimal cutoff values of each marker; 3) whether any such test may help improve diagnostic performance of traditional leukocyte count. Between January/2013 and December/2015 total hip or knee arthroplasty revision cases (regardless of preoperative diagnosis) were prospectively included provided enough synovial fluid for biomarker analysis was collected and at least four tissue samples as well as the implant for sonication were gathered for microbiological study. Definitive diagnosis was classified as infection or aseptic on the basis of the recent International Consensus Meeting definition of PJI. Using receiver operating characteristic curves, we determined cutoff values as well as sensitivity and specificity for each marker.Aim
Method
Previous data from our institution show that more than half of all prosthetic joint infections are due to S. aureus. A significant proportion of these bacteria may have an endogenous source. Detecting and treating asymptomatic S. aureus nasal carriers preoperatively has been shown to reduce the risk of infection. This is an ongoing prospective study that started in March/2009 and involves primary total knee or hip arthroplasties candidates. So far preoperative nasal swab cultures were performed in 211(61%) out of 347 patients operated until April/2010. Carriers are identified and randomly chosen for preoperative treatment consisting of nasal mupirocin twice a day and daily cloro-hexidine baths in the 5 days that precede surgery. Antibiotic prophylaxis is cefazolin 24hours adding a single vancomycin dose in MRSA carriers.Background
Material and Methods
