Our goal is to assess diagnostic accuracy of synovial fluid testing in diagnosing prosthetic joint infection (PJI) as defined by the European Bone and Joint Infection Society (EBJIS). In addition to differential leukocyte count, simples and inexpensive biomarkers such as synovial fluid C-reactive protein (CRP), adenosine deaminase (ADA) and alpha-2-macrogloblulin(A2M) were also investigated and its possible role in increasing accuracy assessed. Between January/2013 and December/2019 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 according to the new EBJIS PJI definition. Using receiver operating characteristic curves, we determined cutoff values as well as diagnostic accuracy for each marker.Aim
Method
C-reactive protein(CRP) and erythrocyte sedimentation rate(ESR) are non-specific markers with variable reported accuracy in the diagnosis of prosthetic joint infection(PJI). They are often used as a part of the initial diagnostics as they are widely available and inexpensive. Given its high false-negative rate, CRP is an insufficient screening tool for PJI especially in low virulence microorganisms. Nevertheless, many advocate ESR offers no added advantage and is useless in this setting. Our goal is to determine if the combined measurement of ESR and CRP offers increased sensitivity for the preliminary screening of PJI over isolated CRP measurement. We retrospectively evaluated every single- or first-stage for presumed aseptic or known infected revision total hip/knee arthroplasty procedures between 2013–2018. Cases without preoperative CRP and ESR measurement as well those without synovial fluid for differential leukocyte count and/or no multiple cultures including sonication of removed implant obtained during surgery were excluded. Diagnostic accuracy was compared against two different PJI definitions: 2013 International Consensus Meeting and ProImplant Foundation definitions.Aim
Method
Treatment of complicated wound healing after total joint arthroplasty is controversial. What exactly constitutes prolonged wound drainage is matter of debate and recommendations to manage it vary considerably. Nonoperative measures are often recommended. If drainage persists, surgery may be indicated. To further intricate decision-making, differentiating superficial from deep surgical site infection is also controversial and inherently complex. Specific cutoffs for synovial fluid leukocyte count and blood C-reactive protein (CRP) in the acute stage have been suggested as a way to superficial infection requiring superficial wound washout from deep infection requiring a formal debridement, antibiotics and implant retention (DAIR) procedure. The goal of this study is to analyze clinical and laboratory findings of an institutional protocol of “aggressively” proceeding with formal DAIR in all patients with complicated wound healing Our indications for DAIR in suspected acute postoperative periprosthetic joint infection (PJI) are: 1)prolonged wound drainage and CRP upward trend after day-3; 2)persistent wound drainage by day-10 regardless of CRP; 3)wound healing disturbance (e.g. “superficial” infection, “superficial” skin necrosis) anytime in early postoperative weeks. We retrospectively evaluated patients undergoing DAIR in the first 60 postoperative days between 2014–2018. Patients without multiple deep tissue cultures obtained intraoperative were excluded. Deep infection was defined by at least two positive deep tissue cultures or one positive deep culture and positive leukocyte count (>10,000 cells/mL or >90% PMN).Aim
Method
Antibiotic loaded spacers are often used during a two-stage exchange for periprosthetic joint infections (PJI) both for its mechanical properties and as a means for local antibiotic delivery. The main goal of this study is to compare the rate of positive cultures during reimplantation with the use of different antibiotic loaded spacers: aminoglycoside only vs. combined glycopeptide/aminoglycoside vs. combined glycopeptide/carbapenem/aminoglycoside. We retrospectively evaluated every two-stage exchange procedures for infected hip/knee arthroplasty between 2012–2018. Microbiological findings in the first and second stage were registered as well as the type of spacer and antibiotic(s) used. Cases in whom no cultures were obtained during reimplantation and cases without sufficient data on antibiotic(s) used in cement spacers were excluded.Aim
Method
Primary tuberculous bursitis was a relatively frequent manifestation of the disease before the antituberculosis drug era. Nowadays, it is considered a rare condition; it accounts for 1–2% of all musculoskeletal tuberculosis. The diagnosis and treatment of tuberculous bursitis may be delayed because the paucity of symptoms, its indolent clinical course and a low clinical suspicion. A 50-year-old patient with tuberculous trochanteric bursitis is reported. A 50-year-old woman was referred to our department to investigate a persistent pain in her left hip with 6 months duration. She was afebrile. The examination revealed a diffuse swelling from the buttock through the thigh, notable over the trochanter, but no sign of acute inflammation such as heat and redness. Her past medical and family histories revealed no previous tuberculosis. Plain films of the left hip showed a partial destruction of the margin of the greater trochanter, lytic foci in the underlying bone and a small focus of calcification in the adjacent soft tissues. A computed tomogram showed a soft tissue mass and demonstrated the relationship with the trochanter. We performed a needle biopsy which revealed granulomatous tissue. The patient underwent complete excision of the bursa and curettage of the surface of the trochanter. The postoperative course was uneventful. Mycobacterium tuberculosis was isolated and definitive diagnosis of tuberculous bursitis was made. There was no evidence of concomitant tuberculosis at other musculoskeletal sites. The patient completed a treatment with rifampicin and etambutol for 6 months. There has been a complete resolution of the symptoms after 3 months and no recurrence after 4 years of follow-up. On plain radiograph the remodeling of the bone structure is clearly visible. Tuberculosis in the region of the greater trochanter is extremely rare. This rarity leads orthopedic surgeons to neglect this potential diagnosis, resulting in a delay in treatment. The pathogenesis of tuberculosis of the greater trochanteric area has not been well defined. The incidence of concomitant tuberculosis at other musculoskeletal sites, as well as the lung, is approximately 50%. Both hematogenous infection and propagation from other locations are reasonable explanations. Surgical intervention is mandatory for cure and the use of several antituberculosis agents is a standard approach.
The goals of the present study are to describe the prevalence of both methicillin sensitive and resistant S.aureus carriage among elective total hip and knee arthroplasty candidates and to evaluate the real impact of preoperatively treating carriers in preventing prosthetic joint infection. Patients undergoing elective primary THA or TKA at a single institution were enrolled in a prospective randomized trial. S.aureus nasal carriage screening was performed in the outpatient setting and selected carriers underwent a 5-day preoperative treatment of nasal mupirocin and chlorhexidine bathing. All patients were followed regularly in the outpatient clinic. No patients were lost to follow-up at a minimum of one year after surgery. The main outcome of the study was the diagnosis of prosthetic joint infection occurring in the first year after surgery including all pathogens and a secondary outcome was defined as infections involving S.aureus bacteria only. From January 2010 to December 2012, 1305 total joint arthroplasties were performed and 1028 of those were screened. We observed a 22.2% (228/1028) S.aureus colonization rate and only eight patients colonized with MRSA (0.8%). Twenty five cases of prosthetic joint infections were identified with an overall infection rate of 2.4%. S.aureus was involved in 14 cases. PJI rate in S.aureus carriers was 3.9% (9/228), which was not significantly higher than the 2.0% (16/800) found among non carriers. Treated and untreated carriers infection rate also showed no significant differences – 3.4% (3/89) vs. 4.3% (6/139). Multivariable analysis substantiates ASA≥ 3 (OR=3.42, 95% CI=1.51 – 7.74) and duration of surgery above the 75th percentile (OR=2.74, 95% CI=1.22 – 6.16) as independent predictors of PJI but not S.aureus carrier state. We obtained similar results when considering infection involving S.aureus bacteria only. Of the 14 cases where S.aureus was present in PJI, only five were carriers preoperatively. Of those five cases, one was an untreated MSSA carrier that ultimately got an MRSA infection. Our results show no clear benefit in screening and decolonizing S.aureus nasal carriers before total joint arthroplasty. There seems to be a lack of causal relation between nasal S.aureus and PJI pathogen as most of S.aureus PJI seems to have an exogenous source.
