Key aInfecƟon is only likely if there is a posiƟve clinical feature or raised serum CRP together with another posiƟve test (synovial fluid, microbiology, histology or nuclear imaging). bExcept in adverse local Ɵssue reacƟon (ALTR) and crystal arthropathy cases. cshould be interpreted with cauƟon when other possible causes of inflammaƟon are present: gout or other crystal arthropathy, metallosis, acƟve inflammatory joint disease (e.g. rheumatoid arthriƟs), periprostheƟc fracture or the early postoperaƟve period. dThese values are valid for hips and knee PJI. Parameters are only valid when clear fluid is obtained and no lavage has been performed. Volume for the analysis should be >250 μL, ideally 1 mL, collected in an EDTA containing tube and analyzed in <1h, preferenƟally using automated techniques. For viscous samples, pretreatment with hyaluronidase improves the accuracy of opƟcal or automated techniques. In case of bloody samples, the adjusted synovial WBC= synovial WBC observed – [WBC blood / RBC blood x RBC synovial fluid] should be used.

Aims The diagnosis of periprosthetic joint infection (PJI) can be difficult. All current diagnostic tests have problems with accuracy and interpretation of results. Many new tests have been proposed, but there is no consensus on the place of many of these in the diagnostic pathway. Previous attempts to develop a definition of PJI have not been universally accepted and there remains no reference standard definition. Methods This paper reports the outcome of a project developed by the European Bone and Joint Infection Society (EBJIS), and supported by the Musculoskeletal Infection Society (MSIS) and the European Society of Clinical Microbiology and Infectious Diseases (ESCMID) Study Group for Implant-Associated Infections (ESGIAI). It comprised a comprehensive review of the literature, open discussion with Society members and conference delegates, and an expert panel assessment of the results to produce the final guidance. Results This process evolved a three-level approach to the diagnostic continuum, resulting in a definition set and guidance, which EBJIS, MSIS, and ESGIAI have fully endorsed. Conclusion The definition presents a novel three-level approach to diagnosis, based on the most robust evidence, which will be useful to clinicians in daily practice. Cite this article: Bone Joint J 2021;103-B(1):18–25.

This international, multi-center study investigated the effect of individual components of surgery on the clinical outcomes of patients treated for fracture-related infection (FRI). All patients with surgically treated FRIs, confirmed by the FRI consensus definition, were included. Data were collected on demographics, time from injury to FRI surgery, soft tissue reconstruction, stabilization and systemic and local anti-microbial therapy. Patients were followed up for a minimum of one year. In total, 433 patients were treated with a mean age of 49.7 years (17–84). The mean follow-up time was 26 months (range 12–72). The eradication of infection was successful in 86.4% of all cases and 86.0% of unhealed infected fractures were healed at the final review. In total, 3.3% required amputation. The outcome was not dependent on age, BMI, the presence of metalwork or time from injury (recurrence rate 16.5% in FRI treated at 1–10 weeks after injury; 13.1% at 11–52 weeks; 12.1% at >52 weeks: p = 0.52). The debridement and retention of a stable implant (DAIR) had a failure rate of 21.4%; implant exchange to a new internal fixation had a failure rate of 12.5%; and conversion to external fixation had a failure rate of 10.3% (adjusted hazard ratio (aHR) DAIR vs. Ext Fix 2.377; 95% C.I. 0.96–5.731). Tibial FRI treated with a free flap was successful in 92.1% of cases and in 80.4% of cases without a free flap (HR 0.38; 95% C.I. 0.14–1.0), while the use of NPWT was associated with higher recurrence rates (HR 3.473; 95% C.I. 1.852–6.512). The implantation of local antibiotics reduced the recurrence from 18.7% to 10.0% (HR 0.48; 95% C.I. 0.29–0.81). The successful treatment of FRI was multi-factorial. These data suggested that treatment decisions should not be based on time from injury alone, as other factors also affected the outcome. Further work to determine the best indications for DAIR, free flap reconstruction and local antibiotics is warranted.

Fracture-related infection (FRI) remains a challenging complication that creates a heavy burden for orthopaedic trauma patients, their families and treating physicians, as well as for healthcare systems. Standardization of the diagnosis of FRI has been poor, which made the undertaking and comparison of studies difficult. Recently, a consensus definition based on diagnostic criteria for FRI was published. As a well-established diagnosis is the first step in the treatment process of FRI, such a definition should not only improve the quality of published reports but also daily clinical practice. The FRI consensus group recently developed guidelines to standardize treatment pathways and outcome measures. At the center of these recommendations was the implementation of a multidisciplinary team (MDT) approach. If such a team is not available, it is recommended to refer complex cases to specialized centers where a MDT is available and physicians are experienced with the treatment of FRI. This should lead to appropriate use of antimicrobials and standardization of surgical strategies. Furthermore, an MDT could play an important role in host optimization. Overall two main surgical concepts are considered, based on the fact that fracture fixation devices primarily target fracture consolidation and can be removed after healing, in contrast to periprosthetic joint infection were the implant is permanent. The first concept consists of implant retention and the second consists of implant removal (healed fracture) or implant exchange (unhealed fracture). In both cases, deep tissue sampling for microbiological examination is mandatory. Key aspects of the surgical management of FRI are a thorough debridement, irrigation with normal saline, fracture stability, dead space management and adequate soft tissue coverage. The use of local antimicrobials needs to be strongly considered. In case of FRI, empiric broad-spectrum antibiotic therapy should be started after tissue sampling. Thereafter, this needs to be adapted according to culture results as soon as possible. Finally, a minimum follow-up of 12 months after cessation of therapy is recommended. Standardized patient outcome measures purely focusing on FRI are currently not available but the patient-reported outcomes measurement information system (PROMIS) seems to be the preferred tool to assess the patients’ short and long-term outcome. This review summarizes the current general principles which should be considered during the whole treatment process of patients with FRI based on recommendations from the FRI Consensus Group.

Background Prosthetic joint infection (PJI) caused by Candida spp is a severe complication of arthroplasty. We investigated the outcomes of Candida PJI. Methods This was a retrospective observational multinational study including patients diagnosed with Candida-related PJI between 2010 and 2021. Treatment outcome was assessed at 2-year follow-up. Results A total of 269 patients were analyzed. Median age was 73.0 (interquartile range [IQR], 64.0–79.0) years; 46.5% of patients were male and 10.8% were immunosuppressed. Main infection sites were hip (53.0%) and knee (43.1%), and 33.8% patients had fistulas. Surgical procedures included debridement, antibiotics, and implant retention (DAIR) (35.7%), 1-stage exchange (28.3%), and 2-stage exchange (29.0%). Candida spp identified were Candida albicans (55.8%), Candida parapsilosis (29.4%), Candida glabrata (7.8%), and Candida tropicalis (5.6%). Coinfection with bacteria was found in 51.3% of cases. The primary antifungal agents prescribed were azoles (75.8%) and echinocandins (30.9%), administered for a median of 92.0 (IQR, 54.5–181.3) days. Cure was observed in 156 of 269 (58.0%) cases. Treatment failure was associated with age &gt;70 years (OR, 1.811 [95% confidence interval {CI}: 1.079–3.072]), and the use of DAIR (OR, 1.946 [95% CI: 1.157–3.285]). Candida parapsilosis infection was associated with better outcome (OR, 0.546 [95% CI: .305–.958]). Cure rates were significantly different between DAIR versus 1-stage exchange (46.9% vs 67.1%, P = .008) and DAIR versus 2-stage exchange (46.9% vs 69.2%, P = .003), but there was no difference comparing 1- to 2-stage exchanges (P = .777). Conclusions Candida PJI prognosis seems poor, with high rate of failure, which does not appear to be linked to immunosuppression, use of azoles, or treatment duration.