Early Prosthetic Joint Infection Research Articles

KLIC Score Does Not Predict Failure After Early Prosthetic Joint Infection: An External Validation With 153 Knees and 130 Hips

BackgroundA preoperative risk score, the KLIC score (chronic renal failure [K], liver cirrhosis [L], indication of the index surgery [I], cemented prosthesis [C], and C-reactive protein >115 mg/L), has been developed to predict the risk of treatment failure after early prosthetic joint infection (PJI). This study aimed to validate the KLIC score for the debridement, antibiotics, and implant retention (DAIR) procedure and one-stage revisions in a Northern European cohort. MethodsRevisions due to early PJI of the hip or knee between January 1, 2008, and September 12, 2021, were identified retrospectively. The primary outcome was early failure, which was considered when the patient needed an unscheduled surgery, the patient died, or the patient was prescribed long-term suppressive antibiotics. To examine the association between KLIC score and failure risk, univariable logistic regression with area under the curve (AUC) was used. In addition, models were calibrated to assess prognostic ability and clinical utility was examined with decision-curve analyses. ResultsAn increase in KLIC score had a moderate predictive value for early failure after DAIR (odds ratio [OR] 1.45; confidence interval [CI] 1.13 to 1.90). For one-stage revision, it was only slightly predictive of failure (OR 1.20; CI 0.93 to 1.56). After 60 days, the AUC for DAIR was 0.63 (CI 0.55 to 0.72) and 0.56 (CI 0.46 to 0.66) for one-stage revisions, indicating poor discriminative ability. The decision-curve analyses revealed that the model did not offer a remarkable net benefit across a range of threshold probabilities. ConclusionsWe demonstrated that the KLIC score is not a reliable predictor of early failure after early PJI in a Northern European cohort. Using the model to guide treatment decisions does not provide any additional clinical utility beyond the baseline strategies.

1312. Incidence and Microbiology of Prosthetic Joint Infection According to Time Following Total Knee Arthroplasty: A Retrospective Cohort Study Among US Veterans

Abstract Background Despite the frequency of total knee arthroplasty (TKA) and clinical impact of prosthetic joint infections (PJIs), the incidence and microbiology of these infections in the United States remains unclear. Our objective was to determine the incidence of PJI occurring ≤ 3 months (early), between > 3 and ≤ 12 months (delayed), and > 12 months (late) after primary TKA and to identify the organisms isolated from microbiologic cultures during each of these periods. Methods We conducted a retrospective study of patients in the Veterans Aging Cohort Study- National Cohort who underwent elective primary TKA in the VA between October 1, 1999 to September 30, 2019. The primary outcome was incident hospitalization with PJI. We estimated incidence rates (events/10,000 person-months) with 95% confidence intervals (CIs) of early, delayed, and late PJI. Poisson regression was used to estimate the incidence rate ratio (IRR) with 95% CI of early and delayed PJI compared to late PJI. The Kaplan-Meier method was used to demonstrate the cumulative incidence of PJI at 3, 12 and 24 months. We measured the frequency of Gram-positive, Gram-negative, fungal, polymicrobial, and culture-negative PJI occurring within each of the three time periods and compared frequencies of interest using Pearson’s chi-squared tests. Results Among 82,401 VHA patients who underwent primary TKA, a total of 1,605 incident PJIs (1.9%) were identified. The incidence rate of PJI was higher in the first 12 months after primary TKA surgery, with an IRR of 20.4 (95% CI, 18.2-222.8) for early and 4.2 (95% CI, 3.7-4.8) for delayed periods when compared to late. The cumulative incidence of PJI at 3 months was 0.77% (95% CI, 0.71-0.83%), at 12 months was 1.25% (95% CI 1.17-1.33%), and at 24 months was 1.56% (95% CI 1.48-1.65%) (Figure 1). Staphylococcus aureus was the most common organism isolated (33.2%) across the periods. Gram-negative bacteria were isolated in 11.1% of all infections, and 15.1% of early PJIs (Table 1). Kaplan Meier failure curves for prosthetic joint infection for the overall study period (upper panel) as well as the first 24 months (lower panel) following primary total knee arthroplasty. Abbreviations: PJI, prosthetic joint infection; CI, confidence interval.Table 1.Organisms isolated from synovial fluid or operative tissue cultures of early, delayed and late prosthetic joint infections after primary total knee arthroplasty. aAmong the 1,605 PJIs in the Overall Cohort, the microbiology data for 103 were missing and 1,502 PJIs with available microbiology data were included in these results. bPolymicrobial defined by multiple genera of organisms identified cIncludes: Micrococcus species, diphtheroids dIncludes: Salmonella, Pasteurella, Citrobacter, Morganella, Acinetobacter, Pasteurella, Burkholderia species, and Gram-negative organisms not otherwise specified eAll fungal infections were identified as Candida species fNumbers may not sum to group totals or percentages as polymicrobial infections with more than one organism were possible Abbreviations: PJI, prosthetic joint infection. Conclusion Incidence rates of early and delayed PJI were significantly higher than late PJI following primary TKA. Gram-negative organisms were more prevalent in early compared to delayed or late PJI. Empiric Gram-negative antibiotic therapy should be considered with a suspected PJI within 3 months after elective primary TKA. Disclosures Alisa Stephens-Shields, PhD, Gilead Sciences: Advisor/Consultant Charles Nelson, MD, Stryker: Advisor/Consultant|Zimmer-Biomet: Advisor/Consultant|Zimmer-Biomet: Grant/Research Support

Debridement, antibiotics and implant retention (DAIR) following hip and knee arthroplasty: results and findings of a multidisciplinary approach from a non-specialist prosthetic infection centre

Introduction Prosthetic joint infection (PJI) is a catastrophic complication following arthroplasty surgery. Recently a debridement, antibiotics and implant retention (DAIR) procedure has gained popularity for PJI where a thorough debridement, irrigation and modular component exchange is undertaken. Method We present the outcome for DAIR, data collected prospectively, in a busy orthopaedic unit but not one specialising in PJI. All patients with PJI were included without loss of data or patients from 2012 to 2018 with a minimum follow-up of 5 years. Results Four total knee replacements, 17 total hip replacements, one revision total hip replacement and three hip hemiarthroplasties are included with an average duration from onset of symptoms to the DAIR procedure of 11 days (range 1–22 days). Staphylococcus aureus (24%) and Staphylococcus epidermidis (32%) were the most common causative organisms, and the most common antibiotic regimens included intravenous teicoplanin and flucloxacillin. Average follow-up was 67 months (range 9–104 months). Only four patients went on to require revision surgery. An analysis of midterm patient outcome measures for 6 of the total hip replacement (THR) DAIR patients were compared with a database of 792 THRs (with a minimum two-year follow-up) carried out by the same surgeon revealed no significant difference in Oxford hip scores at one-year post-surgery (OHS DAIR 36.2 vs 39 for control group). Conclusion This study includes 25 consecutive patients treated with DAIR with only one reinfection, with a mean follow-up period of 5 years. Using a strict protocol, DAIR appears to offer a successful treatment strategy for the management of early PJI.

Incidence, Microbiological Studies, and Factors Associated With Prosthetic Joint Infection After Total Knee Arthroplasty

Despite the frequency of total knee arthroplasty (TKA) and clinical implications of prosthetic joint infections (PJIs), knowledge gaps remain concerning the incidence, microbiological study results, and factors associated with these infections. To identify the incidence rates, organisms isolated from microbiological studies, and patient and surgical factors of PJI occurring early, delayed, and late after primary TKA. This cohort study obtained data from the US Department of Veterans Affairs (VA) Corporate Data Warehouse on patients who underwent elective primary TKA in the VA system between October 1, 1999, and September 30, 2019, and had at least 1 year of care in the VA prior to TKA. Patients who met these criteria were included in the overall cohort, and patients with linked Veterans Affairs Surgical Quality Improvement Program (VASQIP) data composed the VASQIP cohort. Data were analyzed between December 9, 2021, and September 18, 2023. Primary TKA as well as demographic, clinical, and perioperative factors. Incident hospitalization with early, delayed, or late PJI. Incidence rate (events per 10 000 person-months) was measured in 3 postoperative periods: early (≤3 months), delayed (between >3 and ≤12 months), and late (>12 months). Unadjusted Poisson regression was used to estimate incidence rate ratios (IRRs) with 95% CIs of early and delayed PJI compared with late PJI. The frequency of organisms isolated from synovial or operative tissue culture results of PJIs during each postoperative period was identified. A piecewise exponential parametric survival model was used to estimate IRRs with 95% CIs associated with demographic and clinical factors in each postoperative period. The 79 367 patients (median (IQR) age of 65 (60-71) years) in the overall cohort who underwent primary TKA included 75 274 males (94.8%). A total of 1599 PJIs (2.0%) were identified. The incidence rate of PJI was higher in the early (26.8 [95% CI, 24.8-29.0] events per 10 000 person-months; IRR, 20.7 [95% CI, 18.5-23.1]) and delayed periods (5.4 [95% CI, 4.9-6.0] events per 10 000 person-months; IRR, 4.2 [95% CI, 3.7-4.8]) vs the late postoperative period (1.3 events per 10 000 person-months). Staphylococcus aureus was the most common organism isolated overall (489 [33.2%]); however, gram-negative infections were isolated in 15.4% (86) of early PJIs. In multivariable analyses, hepatitis C virus infection, peripheral artery disease, and autoimmune inflammatory arthritis were associated with PJI across all postoperative periods. Diabetes, chronic kidney disease, and obesity (body mass index of ≥30) were not associated factors. Other period-specific factors were identified. This cohort study found that incidence rates of PJIs were higher in the early and delayed vs late post-TKA period; there were differences in microbiological cultures and factors associated with each postoperative period. These findings have implications for postoperative antibiotic use, stratification of PJI risk according to postoperative time, and PJI risk factor modification.

Debridement, Antibiotics and Implant Retention: A Systematic Review of Strategies for Treatment of Early Infections after Revision Total Knee Arthroplasty.

The purpose of this review is to provide a systematic and comprehensive overview of the available literature on the treatment of an early prosthetic joint infection (PJI) after revision total knee arthroplasty (TKA) and provide treatment guidelines. This systematic review was performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines. The search was conducted using the electronic databases of PubMed, Trip, Cochrane, Embase, LILACS and SciElo. After the inclusion of the relevant articles, we extracted the data and results to compose a treatment algorithm for early and acute PJI after revision TKA. After applying the in- and exclusion criteria, seven articles were included in this systematic review focusing on debridement, antibiotics and implant retention (DAIR) for PJI following revision TKA, of which one was prospective and six were retrospective. All studies were qualified as level IV evidence. The current literature suggests that DAIR is a valid treatment option for early infections after revision TKA with success rates of 50-70%. Repeat DAIR shows success rates of around 50%. Further research should be aimed at predicting successful (repeat/two-stage) DAIRs in larger study populations, antibiotic regimes and the cost effectiveness of a second DAIR after revision TKA.

Debridement, antimicrobials, and implant retention in the treatment of late acute and early acute Staphylococcus aureus prosthetic joint infections

Background Staphylococcus aureus is the most common microbe in prosthetic joint infections (PJIs). Debridement, antimicrobials, and implant retention (DAIR) are often-recommended treatment modality for acute PJIs, even though it has had relatively poor outcomes in some studies. In this study, we wanted to examine treatment results with a multidisciplinary team in a specialised centre and obtain further information for treatment decisions in acute Staphylococcus aureus PJIs. Methods All consecutive haematogenous late acute and postoperative early acute hip and knee Staphylococcus aureus PJIs treated with DAIR during 2011–2016 were included in this retrospective study. DAIR within three weeks from symptom onset and the exchange of modular parts were required. Results Eighty-five acute Staphylococcus aureus PJIs were treated with DAIR in 83 patients: 28 late acute and 57 early acute PJIs. The late acute PJI patients were older and had malignancies more often than the early acute PJI patients. Bacteraemia was present in 50.6% of Staphylococcus aureus PJI patients, more often in late acute (73.1%) than in early acute (40.4%) patients (p = .006). The implant was retained in 80.0%: 89.3% of the late acute and 75.4% of the early acute PJIs. In 17 joints, DAIR failed and the joint had to be removed. Fourteen of these joints were successfully replaced. One infection-related death occurred. The one-year all-cause mortality rate was 3.6%. Suppressive antimicrobial treatment was given to 22 (26.5%) patients. Conclusions Reasonably good treatment results for acute Staphylococcus aureus PJIs are achievable by DAIR in a specialised centre with a strict treatment protocol and a multidisciplinary team. If the DAIR fails, a two-stage exchange is usually still possible, with good results.

Success of Debridement, Antibiotics, and Implant Retention in Prosthetic Joint Infection Following Primary Total Knee Arthroplasty: Results From a Prospective Multicenter Study of 189 Cases

BackgroundThis study aimed to identify the success rate of debridement, antibiotics, and implant retention (DAIR) for prosthetic joint infection (PJI) in a large prospective cohort of patients undergoing total knee arthroplasty (TKA). The ability for different PJI classification systems to predict success was assessed. MethodsProspective data recorded in the Prosthetic Joint Infection in Australia and New Zealand Observational study were analyzed. One hundred eighty-nine newly diagnosed knee PJIs were managed with DAIR between July 2014 and December 2017. Patients were prospectively followed up for 2 years. A strict definition of success was used, requiring the patient being alive with documented absence of infection, no ongoing antibiotics and the index prosthesis in place. Success was compared against the Coventry (early PJI ≤1 month), International Consensus Meeting (early ≤90 days), Auckland (early <1 year), and Tsukayama (early ≤1 month, hematogenous >1 month with <7 days symptoms, chronic >1 month with >7 days symptoms) classifications. ResultsDAIR success was 45% (85/189) and was highest in early PJIs defined according to the Coventry (adjusted odds ratio [aOR] = 3.9, P = .01), the International Consensus Meeting (aOR = 3.1, P = .01), and the Auckland classifications (aOR = 2.6, P = .01). Success was lower in both hematogenous (aOR = 0.4, P = .03) and chronic infections (aOR = 0.1, P = .003). ConclusionTime since primary TKA is an important predictor of DAIR success. Success was highest in infections occurring <1 month of the primary TKA and progressively decreased as time since the primary TKA increased.

Dare to DAIR: Is Rifampin Always Necessary?

The treatment of early post-operative staphylococcal prosthetic joint infection (PJI) with debridement, antibiotics, and retention of the implant (DAIR) is becoming increasingly common. This approach has many advantages, primarily more rapid mobilization and return to normal activities compared to a one- or two-stage revision [1]. A recent prospective multicenter observational study conducted at 27 hospitals in Australia and New Zealand found that DAIR was as successful as one or two-stage revisions, especially in patients with acute infections [2]. However, there is still considerable confusion as to the best antibiotics and duration of therapy. Some guidelines have adopted rifampin combination therapy as the cornerstone antibiotic treatment for staphylococcal PJI treated with DAIR, based on experimental animal models, one randomized trial, and several cohort studies [3,4]. However, rifampin combination therapy is associated with significant side effects and drug–drug interactions. A common justification for adding rifampin is a prospective randomized trial of early MSSA PJI conducted by Zimmerli and published in 1998 [5]. This was a prospective, randomized, double-blind trial that showed 100% success with combination therapy compared to 58% in the non-rifampin arm. Only 33 patients were included in this trial and only 24 completed the study. Of the 18 patients in the rifampin arm, there were 5 hip replacements, 3 knee replacements and 10 internal fixation devices. In the placebo arm, there were 3 hip replacements, 4 knee replacements and 8 internal fixation devices. This study was certainly a remarkable accomplishment; however, arguably, it should not be considered the definitive word on how to treat PJI with DAIR and drive clinical practice for decades. Unfortunately, it seems that this has been the case given the recommendations of current guidelines.

A retrospective study of risk factors, causative micro-organisms and healthcare resources consumption associated with prosthetic joint infections (PJI) using the Clinical Practice Research Datalink (CPRD) Aurum database.

Prosthetic joint infection (PJI) is a serious complication after joint replacement surgery and it is associated with risk of mortality and morbidity along with high direct costs. The Clinical Practice Research Datalink (CPRD) data were utilized to quantify PJI incidence after hip or knee replacement up to 5 years after implant and a variety of risk factors related to patient characteristics, medical and treatment history along with characteristics of the original surgery were analyzed through Cox proportional hazard. 221,826 patients (individual joints 283,789) met all the inclusion and exclusion criteria of the study; during the study follow-up period (5 years), 707 and 695 PJIs were diagnosed in hip and knee, respectively. Patients undergoing joint replacement surgery during an unscheduled hospitalization had greater risk of PJI than patients whose surgery was elective; similarly, the risk of developing PJI after a secondary hip or knee replacement was about 4 times greater than after primary arthroplasty when adjusted for all other variables considered. A previous diagnosis of PJI, even in a different joint, increased the risk of a further PJI. Distribution of average LoS per each hospitalization caused by PJI exhibited a right skewed profile with median duration [IQR] duration of 16 days [8-32] and 13 days [7.25-32] for hip and knee, respectively. PJIs causative micro-organisms were dependent on the time between initial surgery and infection offset; early PJI were more likely to be multispecies than later (years after surgery); the identification of Gram- pathogens decreased with increasing post-surgery follow-up. This study offers a contemporary assessment of the budgetary and capacity (number and duration of hospitalizations along with the number of Accident and Emergency (A&E) visits) posed by PJIs in UK for the national healthcare system (NHS). The results to provide risk management and planning tools to health providers and policy makers in order to fully assess technologies aimed at controlling and preventing PJI. The findings add to the existing evidence-based knowledge surrounding the epidemiology and burden of PJI by quantifying patterns of PJI in patients with a relatively broad set of prevalent comorbidities.

Aspirin Thromboprophylaxis Following Primary Total Knee Arthroplasty Is Associated With a Lower Rate of Early Prosthetic Joint Infection Compared With Other Agents

BackgroundPatients undergoing total knee arthroplasty (TKA) are at increased risk of venous thromboembolism (VTE). Aspirin has been shown to be effective at reducing rates of VTE. In select patients, more potent thromboprophylaxis is indicated, which has been associated with increased rates of bleeding and wound complications. This study aimed to evaluate the effect of thromboprophylaxis choice on the rates of early prosthetic joint infection (PJI) following TKA. MethodsA review of 11,547 primary TKA patients from 2013 to 2019 at a single academic orthopaedic hospital was conducted. The primary outcome measure was PJI within 90 days of surgery as measured by Musculoskeletal Infection Society criteria. There were 59 (0.5%) patients diagnosed with early PJI. Chi-square and Welch-2 sample t-tests were used to determine statistically significant relationships between thromboprophylaxis and demographic variables. Significance was set at P < .05. Multivariate logistic regression adjusted for age, body mass index, sex, and Charlson comorbidity index was performed to identify and control for independent risk factors for early PJI. ResultsThere was a statistically significant difference in the rates of early PJI between the aspirin and non-aspirin group (0.3 versus 0.8%, P < .001). Multivariate logistic regressions revealed that patients given aspirin thromboprophylaxis had significantly lower odds of PJI (odds ratios = 0.51, 95% confidence interval = 0.29-0.89, P = .019) compared to non-aspirin patients. ConclusionThe use of aspirin thromboprophylaxis following primary TKA is independently associated with a lower rate of early PJIs. Arthroplasty surgeons should consider aspirin as the gold standard thromboprophylaxis in all patients in which it is deemed medically appropriate and should carefully weigh the morbidity of PJI in patients when non-aspirin thromboprophylaxis is considered. Level of EvidenceRetrospective, Therapeutic Level III.

Corynebacterium striatum Prosthetic Joint Infection Successfully Treated with Long-Term Dalbavancin

Arthroplasty surgery is a common procedure that significantly improves quality of life. The most feared complication is prosthetic joint infection (PJI), which occurs more often following revision surgery. Staphylococci are the most prevalent bacteria in PJIs, although many other pathogens have been reported. We describe a case of PJI in a 75-year-old farmer following revision surgery caused by Corynebacterium striatum, an unusual agent which normally occurs in the normal human skin microbiota with perceived low pathogenicity. Following a cemented right-sided total hip arthroplasty in 2006, a one-stage revision due to an osteolytic process in the right femur took place in 2020 with negative intraoperative tissue cultures. Three weeks later, the patient presented a fulminant infection which was treated with debridement, antibiotics, and implant retention (DAIR). Tissue biopsies showed C. striatum in 6/6 samples including small colony variants. Genome sequencing showed that all isolates differed by ≤6 SNPs with the same gene content related to resistance (tet(W) and erm(X)). The patient was sequentially treated with vancomycin, linezolid, and daptomycin, but due to side effects, treatment was changed to 12 weeks of dalbavancin as a 1000 mg loading dose followed by 500 mg intravenously/week. Impaired renal function during vancomycin treatment was normalized, and >1 year after finishing antibiotic treatment the outcome was still favourable. In conclusion, a case of a fulminant early post-interventional PJI due to C. striatum was successfully treated with DAIR and long-term dalbavancin therapy without any adverse reactions.

Biofilm formation is associated with poor outcome in prosthetic joint infections caused by Staphylococcus lugdunensis

Background Staphylococcus lugdunensis has been described as a pathogen of increasing importance in prosthetic joint infections (PJI). Our aim was to describe the clinical presentation of PJI caused by S. lugdunensis, and to correlate the biofilm-forming ability of the bacterial isolates to clinical outcome. Method S. lugdunensis isolates from PJI episodes during 2015–2019 were included and analysed for biofilm formation using a microtiter plate assay. Medical records from the corresponding patients were reviewed. Results We identified 36 patients with PJI caused by S. lugdunensis during the study period. Early postoperative PJIs were most frequent (n = 20, 56%). Surgical intervention was performed in a majority of the patients (n = 33, 92%), and the dominating type of antibiotic treatment was a combination of rifampicin and ciprofloxacin (n = 27, 75%). The treatment success-rate was 81% (n = 29). All isolates causing PJI were able to form biofilm in vitro. Biofilm formation was significantly stronger in isolates causing relapsing vs non-relapsing PJI (mean OD550 3.1 ± 0.23 vs 1.14 ± 0.73 p = .001) and strong biofilm formation was also associated with late acute hematogenic PJI (mean OD550 1.8 ± 0.93 vs. 0.93 ± 0.81, p = .01). Conclusion Strong biofilm production in S. lugdunensis isolates was associated with relapse in PJI.

Intraosseous Vancomycin May Not Be Helpful in Aseptic Revision Knee Arthroplasty: A Single-Surgeon Consecutive Case Series

BackgroundInfection after aseptic revision total knee arthroplasty (TKA) has been reported from 9% to 14%. Intraosseous (IO) vancomycin infusion has decreased the risk of infection after primary TKA. The results of this additional prophylaxis were evaluated in aseptic revision TKA. MethodsIn this prospective, single-surgeon study of 20 consecutive patients having aseptic revision TKA, 500 milligrams of vancomycin in 120 mL of saline were infused into the tibia prior to incision, in addition to intravenous (IV) cefazolin. There were 18 men and 2 women who had a mean age of 67 years (range, 47-79), and mean body mass index of 34.4 (range, 25.9-51.2). The knees were aspirated in the operating room prior to IV and IO antibiotics. The outcomes were infections at 90 days requiring reoperation and complications from the infusion. ResultsThree of the 20 aseptic revisions had early prosthetic joint infection, 2 with gram-negative organisms and one with coagulase-negative Staphylococcus. All had debridement, liner exchange and IV antibiotic treatment, but 1 patient eventually had an above knee amputation. No patient had total body “erythema syndrome”, but 1 patient had transient facial flushing. Six patients had a transient elevation of serum creatinine including 3 with an abnormal preoperative serum creatinine. ConclusionIn this small series of aseptic revision TKA, there was no added benefit of IO vancomycin infusion, but there were no infections with methicillin-resistant Staphylococcus aureus. Additional studies are needed before this technique should be routinely recommended.

TIME SINCE PRIMARY TOTAL KNEE ARTHROPLASTY PREDICTS THE SUCCESS OF DEBRIDEMENT, ANTIBIOTICS, AND IMPLANT RETENTION FOR PROSTHETIC JOINT INFECTION: RESULTS FROM A PROSPECTIVE, MULTICENTRE STUDY OF 189 CASES

This study aimed to identify the success rate of debridement, antibiotics and implant retention (DAIR) for prosthetic joint infection (PJI) in a large prospective cohort of patients undergoing total knee arthroplasty (TKA). The ability for different PJI classification systems to predict DAIR success was assessed.A prospective, multicenter study of PJIs occurring between July 2014 and December 2017 in 27 hospitals across Australia and New Zealand was performed. First time PJIs following primary TKA that were managed with DAIR were analyzed. DAIR success was defined as the patient being alive with documented absence of clinical or microbiological evidence of infection and no ongoing antibiotics for the index joint at 2-year follow-up. Multivariate analysis was performed for multiple PJI classification systems to assess their ability to predict DAIR success using their respective definitions of “early” PJI (Coventry ≤1 month, International Consensus Meeting ≤90 days or Auckland &lt;1 year), or as hematogenous versus chronic PJI (Tsukayama).189 PJIs were managed with DAIR, with an overall success rate of 45% (85/189). Early PJIs had a higher rate of DAIR success when analyzed according to the Coventry system (adjusted odds ratio = 3.85, p = 0.008), the ICM system (adjusted odds ratio = 3.08, p = 0.005) and the Auckland system (adjusted odds ratio = 2.60, p = 0.01). DAIR success was lower in both hematogenous (adjusted odds ratio = 0.36, p = 0.034) and chronic PJIs (adjusted odds ratio = 0.14, p = 0.003) occurring more than one year since the primary TKA.DAIR success is highest when performed in infections occurring within one year of the primary TKA. Late infections had a high DAIR failure rate irrespective of their classification as hematogenous or chronic. Time since primary is a useful predictor of DAIR success.

Effectiveness and Optimal Duration of Adjunctive Rifampin Treatment in the Management of Staphylococcus aureus Prosthetic Joint Infections After Debridement, Antibiotics, and Implant Retention.

BackgroundRifampin is recommended as adjunctive therapy for patients with a Staphylococcus aureus prosthetic joint infection (PJI) managed with debridement, antibiotics, and implant retention (DAIR), with no solid consensus on the optimal duration of therapy. Our study assessed the effectiveness and optimal duration of rifampin for S aureus PJI using Veterans Health Administration (VHA) data.MethodsWe conducted a retrospective cohort study of patients with S aureus PJI managed with DAIR between 2003 and 2019 in VHA hospitals. Patients who died within 14 days after DAIR were excluded. The primary outcome was a time to microbiological recurrence from 15 days up to 2 years after DAIR. Rifampin use was analyzed as a time-varying exposure, and time-dependent hazard ratios (HRs) for recurrence were calculated according to the duration of rifampin treatment.ResultsAmong 4624 patients, 842 (18.2%) received at least 1 dose of rifampin; 1785 (38.6%) experienced recurrence within 2 years. Rifampin treatment was associated with significantly lower HRs for recurrence during the first 90 days of treatment (HR, 0.60 [95% confidence interval {CI}, .45–.79]) and between days 91 and 180 (HR, 0.16 [95% CI, .04–.66]) but no statistically significant protective effect was observed with longer than 180 days (HR, 0.57 [95% CI, .18–1.81]). The benefit of rifampin was observed for subgroups including knee PJI, methicillin-susceptible or -resistant S aureus infection, and early or late PJI.ConclusionsThis study supports current guidelines that recommend adjunctive rifampin use for up to 6 months among patients with S aureus PJI treated with DAIR.

Higher 1-year risk of implant removal for culture-positive than for culture-negative DAIR patients following 359 primary hip or knee arthroplasties

Background and purpose: To date, the value of culture results after debridement, antibiotics, and implant retention (DAIR) for early (suspected) prosthetic joint infection (PJI) as risk indicators in terms of prosthesis retention is not clear. At the 1-year follow-up, the relative risk of prosthesis removal was determined for culture-positive and culture-negative DAIR patients after primary total hip or knee arthroplasty. The secondary aim of this work was to explore differences in patient characteristics, infection characteristics, and outcomes between these two groups. Methods: A retrospective regional registry study was performed in a group of 359 patients (positive cultures: ; negative cultures: ) undergoing DAIR for high suspicion of early PJI in the period from 2014 to 2019. Differences in patient characteristics, the number of deceased patients, and the number of subsequent DAIR treatments between the culture-positive and culture-negative DAIR groups were analysed using independent tests, Mann–Whitney tests, Pearson's chi-square tests, and Fisher's exact tests. Results: The overall implant survival rate following DAIR was 89 %. The relative risk of prosthesis removal was 7.4 times higher (95 % confidence interval (CI) 1.0–53.1) in the culture-positive DAIR group (37 of 299, 12.4 %) compared with the culture-negative DAIR group (1 of 60, 1.7 %). The culture-positive group had a higher body mass index (), a rate of wound leakage of d (), and more subsequent DAIR treatments (). Interpretation: As implant survival results after DAIR are favourable, the threshold to perform a DAIR procedure for early (suspected) PJI should be low in order to retain the prosthesis. A DAIR procedure in the case of negative cultures does not seem to have unfavourable results in terms of prosthesis retention.

Early Infection After Aseptic Revision Knee Arthroplasty: Prevalence and Predisposing Risk Factors.

Although patient factors have been associated with prosthetic joint infection (PJI) after primary total knee arthroplasty, there are insufficient data on the relationship of patient and technical factors with early PJI after aseptic revision. This is a retrospective study of 157 aseptic revisions performed by 2 surgeons at 1 academic center. A negative intraoperative culture during revision surgery was required for inclusion. Mean follow-up time was 3.8 years (standard deviation 2.8). PJI was defined by positive aspiration or draining wound, and an additional operation within 1 year of aseptic revision. Patient demographics, medical comorbidities, and technical factors were reviewed. Data points were evaluated with univariate and adjusted multivariate regression analyses. The prevalence of PJI after aseptic revision was 9% (14/157). The most common organism was Staphylococcus aureus. Initial treatment included debridement and liner exchange (11) and antibiotic spacer (3). Two patients ultimately had an above-knee amputation. Univariate analysis showed a significant difference in preoperative anemia (P < .01), transfusion (P < .01), and diabetes (P= .05) between cohorts. There was no association among the length of surgery, use of a metaphyseal cone, or the number of components revised and PJI. Adjusted logistic regression demonstrated that preoperative anemia (P < .01) was a significant risk factor for PJI. The prevalence of early PJI was similar to other studies in the literature. Anemia was an independent predictor of PJI, while technical factors did not have an association. Medical optimization of patients should be considered prior to revision surgery.

Differing Microorganism Profile in Early and Late Prosthetic Joint Infections Following Primary Total Knee Arthroplasty — Implications for Empiric Antibiotic Treatment

BackgroundProsthetic joint infection (PJI) is the leading cause of revision following total knee arthroplasty (TKA). Prior to microorganism identification, the choice of the correct empiric antibiotics is critical to treatment success. This study aims to 1) compare the microorganism and resistance profile in early and late PJIs; 2) recommend appropriate empiric antibiotics. MethodsA multicentre retrospective review was performed over a 15-year period. First episode PJIs were classified by both the Tsukayama Classification and Auckland Classification. For each PJI case, the causative organism and antibiotic sensitivity were recorded. ResultsOf eligible patients, 232 culture-positive PJI cases were included. Using either classification system, early PJIs (<4 weeks or <1 year since primary) were significantly more likely to be resistant and polymicrobial. The predominant organisms were coagulase-negative Staphylococci in early PJIs while Staphylococcus aureus was the most common in late PJIs. The distribution of gram-negative cases was higher in early Class-A than late Class-C PJIs (25% versus 6%, P = .004). Vancomycin provided significantly superior coverage when compared to Flucloxacillin for early infections, and addition of a gram-negative agent achieved coverage over 90% using both classification systems. ConclusionBased on the microbiological pattern in Tsukayama criteria, Vancomycin with the consideration of Gram-negative agent should be considered for Class-A infections given the high proportion of resistant and polymicrobial cases. For Class-C infections, Cephazolin or Flucloxacillin is likely sufficient. We recommend antibiotics to be withheld in Class-B infections until cultures and sensitivities are known.

Risk Factors of DAIR Failure and Validation of the KLIC Score: A Multicenter Study of Four Hundred Fifty-Five Patients.

Background: Debridement, antibiotic agents, and implant retention (DAIR) is a currently accepted approach for the treatment of early prosthetic joint infections (PJI). The success of a DAIR procedure has shown variable results throughout the published literature. Scoring systems such as the Kidney, Liver, Index surgery, Cemented prosthesis, and C-reactive protein value (KLIC) score for the selection of patients that are likely to benefit from DAIR have proved to be helpful in decision making. Our study aims to further validate the KLIC score using a large external multicentric cohort and to evaluate other risk factors for failure. Patients and Methods: A retrospective analysis of patients with an early acute PJI who were treated with DAIR and recorded in a database of eight Spanish university hospitals was performed. According to pre-operative variables of the KLIC study, patients were categorized into five groups: group A, ≤2 points; group B, 2.5-3.5 points; group C, 4-5 points; group D, 5.5-6.5 points; and group E, ≥7 points. Failure rates were compared between groups at 60 days and after 60 days of DAIR. Further variables for risk of failure were also analyzed. Results: A total of 455 patients with early acute PJI were included in the analyses. At 60 days, patients presenting with pre-operative elevated C-reactive protein serum levels, Staphylococcus aureus, and polymicrobial infections were associated with failure. Failure rates recorded were 12% for group A (n = 210), 18% for group B (n = 83), 26% for group C (n = 89), 24% for group D (n = 66), and 0% for group E (n = 7). Univariable analysis between consecutive groups of the KLIC score showed no differences for failure before 60 days of the DAIR procedure. Scheduled surgery and having the procedure performed by a specialized unit were also identified as important factors for DAIR success. Conclusions: Our results suggest the KLIC score was not useful for predicting failure in our cohort. Furthermore, our results indicate a specialized unit should conduct DAIR procedures.

The poor accuracy of D-dimer for the diagnosis of prosthetic joint infection but its potential usefulness in early postoperative infections following revision arthroplasty for aseptic loosening

BackgroundD-dimer was introduced in 2018 as an alternative biomarker for C-reactive protein (CRP) in the diagnostic of prosthetic joint infection (PJI) criteria of the Musculoskeletal Infection Society. We assessed the accuracy of plasma D-dimer for the diagnosis of early, delayed, and late PJI according to Infectious Diseases Society of America (IDSA) criteria, and whether persistently high levels of D-dimer in cases of aseptic loosening (AL) may be predictive of subsequent implant-related infection.MethodsA prospective study of a consecutive series of 187 revision arthroplasties was performed at a single institution. Septic (n = 39) and aseptic revisions (n = 141) were classified based on IDSA criteria. Preoperative assessment of CRP, erythrocyte sedimentation rate (ESR) and D-dimer was performed. Receiver operating curves were used to determine maximum sensitivity and specificity of the biomarkers. The natural progress of D-dimer for AL cases was followed up either until the date of implant-related infection at any time during the first year or 1 year after revision in patients without failure. Clinical outcomes for those AL cases included infection-related failure that required a new surgery or need for antibiotic suppression.ResultsPreoperative D-dimer level was significantly higher in PJI cases than in AL cases (p = 0.000). The optimal threshold of D-dimer for the diagnosis of PJI was 1167 ng/mL. For overall diagnosis of PJI, C-reactive protein (CRP) achieved the highest sensitivity (84.6%), followed by erythrocyte sedimentation rate (ESR) and D-dimer (82% and 71.8%, respectively). Plasma D-dimer sensitivity was lower for all PJI types. When combinations of 2 tests were studied, the combined use of ESR and CRP achieved the best accuracy for all types of PJI (76.9%). 4.25% of AL cases had implant failure due to implant-related infection during the first year after the index revision arthroplasty, only the cases with early failure maintained high D-dimer levels.ConclusionsPlasma D-dimer did not offer an improvement over the individual or combined diagnosis for any type of PJI according to IDSA criteria. Persistently raised levels of D-dimer after revision arthroplasty in AL cases might be used to effectively diagnose early postoperative infection.