One-stage Revision With Catheter Infusion of Intraarticular Antibiotics Successfully Treats Infected THA

Intra-articular antibiotics : a direct approach to the treatment of infected cementless total hip arthroplasty

Aims

The use of intra-articular antibiotics in the treatment of periprosthetic joint infection (PJI) can achieve a concentration which is sufficient to eradicate a biofilm. This may mitigate the need for removal of infected but well-fixed cementless components of a total hip arthroplasty (THA). However, the use of percutaneous catheters might lead to multiresistance or persistent multiorganism infections. The aim of this study was to report the results of a series in which an intra-articular antibiotic infusion was added to a single-stage revision for infected cementless THAs.

Methods

A total of 18 patients underwent 18 single-stage revision THAs which were performed for acute (n = 9) or chronic (n = 9) PJI, following a primary (n = 12) or revision (n = 6) cementless THA. After an extensive debridement, modular components were replaced, but all well-fixed components were retained. Two Hickmann catheters were introduced into the joint space, through which intra-articular antibiotics were introduced for two weeks. Intravenous antibiotics were also administered during this time, followed by oral antibiotics until three months after surgery.

Results

At a mean follow-up of 5.4 years (3.3 to 7.19), all patients had a normal ESR and white blood cell count. The CRP remained slightly elevated in three patients, although they were pain-free and showed no signs of infection. No patient developed antibiotic-related renal or systemic dysfunction postoperatively.

Conclusion

We found that for the treatment of an infected cementless THA, retention of well-fixed components was feasible, with the addition of intra-articular antibiotics to a standard single-stage regime. None of the 18 patients had persistent infection or catheter-induced drug resistance, at a mean follow-up of 5.4 years.

Dynamics of Synovial Fluid Markers Following Single-Stage Exchange and Debridement, Antibiotics, and Implant Retention Procedure With Topical Antibiotic Infusion in Treating Periprosthetic Joint Infection

BACKGROUND

Periprosthetic joint infection (PJI) is a severe complication following total joint arthroplasty. This study aimed to investigate the dynamics of synovial fluid markers following single-stage exchange arthroplasty or debridement, combined with antibiotics and implant retention with topical antibiotic infusion for PJI.

METHODS

This retrospective study analyzed patient records at a tertiary hospital from March 1, 2018, to May 1, 2023. Patients who received single-stage exchange arthroplasty or debridement, combined with antibiotics and implant retention, followed by intra-articular antibiotic infusion for PJI, were included. Basic demographic details, comorbidities, Charlson Comorbidity Index scores, microorganism profile, presence of sinus tract, and antibiotic treatment type were collected. Synovial fluid samples were collected preoperatively and postoperatively every two days for 14 days to quantify synovial white blood cell (WBC) count and polymorphonuclear cell percentage (PMN%).

RESULTS

The study included 140 patients who had a mean age of 63 years and a mean body mass index of 25. The results showed a steady decrease in synovial WBC count from preoperative levels to day 14 postoperatively. Patients who had successful outcomes had significantly higher preoperative WBC counts compared to those who had a treatment failure. The synovial PMN% initially increased postoperatively, peaking at days one to two, and then gradually declined. Patients who had successful outcomes showed a faster decline in PMN% compared to those who had persistent infections. Different bacteria exhibited varying preoperative synovial WBC counts and PMN%, but these differences were not statistically significant.

CONCLUSIONS

Monitoring synovial WBC count and PMN% can help distinguish between normal postoperative inflammation and persistent infection. Higher preoperative synovial WBC counts are associated with successful outcomes, suggesting their potential role in predicting treatment success. Future research with larger sample sizes is necessary to further validate these findings and improve the management and diagnosis of PJI.

One-Stage Revision Using Cementless Reconstruction for Chronically Infected Total Hip Arthroplasty: An Average of 11 Years of Follow-Up

BACKGROUND

Although interest in one-stage revision has increased in recent years, long-term follow-up reports remain notably scarce. This study aimed to present the 11-year outcomes of cementless one-stage revision for chronically infected total hip arthroplasty (THA), including infection-free survivorship, radiographic and clinical outcomes, and complications.

METHODS

A retrospective analysis conducted between 2010 and 2016 included 126 patients who had chronically infected THA and underwent one-stage revision using cementless reconstruction. Kaplan-Meier survival analysis was used to assess postoperative survival, while Cox regression analysis identified risk factors for reinfection. Updated postoperative imaging, Harris Hip Scores, and complications were recorded. Successful infection treatment was defined as the absence of clinical symptoms of infection during follow-up.

RESULTS

During a mean follow-up period of 11 years (range, eight to 14), 16 patients experienced infection recurrence, resulting in a 10-year infection-free survival rate of 85.4%. Cox regression analysis identified age ≥ 65 years (HR [hazard ratio] 3.0, 95% CI [confidence interval] 1.2 to 8.6; P = 0.02) and American Society of Anesthesiologists grade III (HR 3.1, 95% CI 1.1 to 8.1; P = 0.03) as significant risk factors for reinfection. The presence of a sinus tract, prolonged operative time, culture-negative periprosthetic joint infection, methicillin-resistant pathogen infection, and prior surgery for infection were not associated with recurrence. Among the patients, two experienced recurrent dislocations and one had aseptic loosening, leading to a 10-year aseptic rerevision-free survival rate of 97.0%. The mean postoperative Harris Hip Scores at the latest follow-up was 77.9 points (range, 68.5 to 86.7; P < 0.001). Complications occurred in 26 patients (23.4%), and the 10-year reoperation-free survival rate was 78.7%.

CONCLUSIONS

A one-stage revision using cementless reconstruction for infected THA demonstrated a favorable infection control rate and sustained satisfactory clinical outcomes. However, further studies with higher-level evidence are needed to validate these findings.

Potential interactions between vancomycin and meropenem in culture-negative periprosthetic joint infection: an in vitro study

BACKGROUND

Culture-negative periprosthetic joint infections (CN-PJIs) represent a critical subtype of PJI, and their high prevalence poses substantial challenges for treatment. CN-PJI is commonly managed utilizing antibiotic combinations, however, the interactions between these antibiotics have not been investigated. The aim of study was to investigate the synergistic and antagonistic effects of vancomycin (VAN) and meropenem (MEM), in an in vitro model of CN-PJI.

METHODS

Minimum Inhibitory Concentration (MIC), Minimum Bactericidal Concentration (MBC), Minimum Biofilm Inhibitory Concentration (MBIC), and Minimum Biofilm Eradication Concentration (MBEC) were determined for VAN and MEM. Fractional Inhibitory Concentration (FIC) and Fractional Biofilm Eradication Concentration (FBEC) indices were calculated to assess the synergistic or antagonistic effects of VAN in combination with MEM on Staphylococcus aureus (S. aureus), Staphylococcus epidermidis (S. epidermidis), and Escherichia coli (E. coli) incubated alone or in combination.

RESULTS

In the planktonic bacterial phase, MEM showed higher activity than VAN. Resistance increased when the bacteria were cultured together. The combination of VAN and MEM exhibited an indifferent effect against individual Staphylococci but an antagonistic effect against polymicrobial cultures. In biofilm, MEM demonstrated better antibiofilm activity than VAN, especially against E. coli biofilms. The combination of VAN and MEM showed an indifferent effect against E. coli and S. epidermidis-E. coli biofilms, but an antagonistic effect against S. aureus, S. epidermidis, S. aureus-S. epidermidis, and S. aureus-E. coli biofilms.

CONCLUSION

This study provides valuable insights into the effectiveness of VAN and MEM combinations in treating CN-PJIs, highlighting the need for careful consideration when selecting antibiotic treatments for these infections.

CLINICAL TRIAL NUMBER

Not applicable.

Osteonecrosis with Concomitant Septic Arthritis of Bilateral Hips following Severe COVID-19 Infection: A Case Report

Introduction

Among the various musculoskeletal manifestations of post-acute Coronavirus disease 2019 (COVID-19) syndrome, osteonecrosis and pyogenic infections are of serious concern due to their potential for joint destruction and the need for major surgery, even among young patients. Spontaneous septic arthritis is rare among healthy adults. Very few cases of osteonecrosis of the femoral heads (ONFH) with concomitant septic arthritis of the hip following a COVID-19 infection are reported in the literature.

Case Report

We report the case of a 43-year-old male patient, who presented with bilateral ONFHs and concomitant septic arthritis of the hips (caused by Pseudomonas aeruginosa), 8 weeks following a severe COVID-19 infection. His serum inflammatory markers were elevated. Radiologic findings were equivocal, and suggestive of osteonecrosis, with possible septic arthritis of the hip. In view of disabling end-stage arthritis, he was advised bilateral total hip arthroplasty (THA), in one or two stages, depending on the intraoperative findings. The diagnosis of infection was confirmed through intraoperative frozen section analysis. Bilateral two-staged THA was performed. At 3 years' follow-up, the patient had no recurrence of symptoms, and was found to be doing well, with a Harris Hip Score of 93 points, and no limb length discrepancy.

Conclusion

COVID-19 infection predisposes patients to the development of ONFH. Concomitant septic arthritis of the hip, however, is scarcely reported, and needs to be ruled out in cases with rapid progression of symptoms.

Exploring Acute Kidney Injury Incidence in Hip Periprosthetic Joint Infection Treatment With Combined Intravenous and Intra-articular Antibiotic Infusion

Background

Periprosthetic joint infections (PJIs) are a significant complication following total hip arthroplasty, impacting patient health and healthcare costs. This study examines the incidence of acute kidney injury (AKI) in patients undergoing hip PJI treatment with a combination of intravenous and intra-articular antibiotic infusion therapies.

Methods

A retrospective review of 151 patient records from May 1, 2010 to December 30, 2022 was conducted at a single academic hospital. Patients were treated for hip PJIs using debridement, antibiotics, and implant retention or single-stage revision surgeries. AKI was classified according to the Kidney Disease: Improving Global Outcomes criteria.

Results

Among 151 patients, 17 (11.26%) developed AKI, with 13 cases resolving transiently before discharge. The median onset of AKI was on postoperative day 2, with stage I AKI being the most prevalent, accounting for 64.71% of cases. Diabetes and low baseline serum creatinine levels were identified as independent risk factors for AKI, with odds ratios of 9.69 and 1.09, respectively.

Conclusions

The combined regimen of intra-articular and intravenous antibiotic infusion appears to have a manageable risk profile regarding AKI. This approach could serve as a viable alternative for PJI management, emphasizing the importance of careful patient monitoring and tailored antibiotic regimens. Further studies are recommended to optimize treatment protocols and mitigate risks.

Comparative reinfection rate of one-stage versus two-stage revision in the management of periprosthetic joint infection following total hip arthroplasty: a meta-analysis

BACKGROUND

Debates persist on the optimal surgical approach for treating Periprosthetic joint infection (PJI) following total hip arthroplasty (THA). This meta-analysis aimed to compare the reinfection rate of one-stage revision versus two-stage revision for PJI after THA.

METHODS

A comprehensive search was performed in four databases (PubMed, Embase, Web of Science, and Cochrane Library) to locate articles that assessed the reinfection rate of one-stage revision compared to two-stage revision. Meta-analyses of reinfection rate were performed.

RESULTS

A total of 14 articles including of 1429 patients were chosen for inclusion in this meta-analysis, with 561 patients in the one-stage group and 868 patients in the two-stage group. The meta-analysis of the 14 trials revealed that there was no statistically significant disparity in the reinfection rate between the two groups(OR = 1.34, 95% CI 0.92 ~ 1.93, P = 0.12, I2 = 0). A subgroup analysis was conducted based on the presence of a well-defined algorithm for decision making in either a one-stage or two-stage revision. There was no statistically significant difference in reinfection rate between one-stage and two-stage revision if there was a decision algorithm(OR = 0.83, 95% CI 0.44 ~ 1.54, P = 0.55, I2 = 0). If not, the reinfection rate of one-stage revision was significantly higher than that of two-stage revision(OR = 1.79, 95% CI 1.11 ~ 2.88, P = 0.02, I2 = 0). Postoperative hip function score was significantly better in the one-stage revision group than that of the two-stage revision group(SMD = 0.54, 95% CI 0.31 ~ 0.78, P<0.05, I2 = 79%).

CONCLUSIONS

A strategy that is clearly defined and can be used for decision making in one-stage or two-stage revision is necessary for the treatment of PJI after THA. When there is significant damage to the soft tissue and/or the presence of strong microorganisms, a two-stage revision is recommended in order to decrease the reinfection rate. One-stage revision is recommended for patients with low-toxic infections and intact soft tissue.

TRIAL REGISTRATION

PROSPERO (CRD42023450842, 17 August 2023) https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42023450842 .

Local antibiotic delivery via intra-articular catheter infusion for the treatment of periprosthetic joint infection: a systematic review

INTRODUCTION

There is an increasing interest in the use of intra-articular (IA) antibiotic infusion as a stand-alone or adjuvant therapy to standard revision surgery for periprosthetic joint infection (PJI). The objective of this systematic review is to evaluate the evidence with respect to this up-and-coming treatment modality.

METHODS

A systematic review of studies published until April 2023 was conducted using PubMed, Embase, MEDLINE and Cochrane databases. Quality assessment was performed with the National Institute of Health quality assessment tool. Inclusion criteria were adult patients (≥ 18 years) with a mean follow-up of ≥ 11 months and a score ≥ 6 on the National Institute of Health quality assessment tool. Primary outcome was eradication of infection.

RESULTS

15 articles, encompassing 631 PJIs in 626 patients, were included in the final analysis, all level IV case series. The majority was treated with single-stage revision with adjuvant IA antibiotic infusion (79.1%). The remaining PJIs were treated with stand-alone IA antibiotic infusion (12.2%), DAIR (debridement, antibiotics and implant retention) with adjuvant IA antibiotic infusion (5.7%) or two-stage revision with adjuvant IA antibiotic infusion (3.0%). Mean duration of IA antibiotic infusion was 19 days (range 3-50). An overall failure rate of approximately 11% was found. In total 117 complications occurred, 71 were non-catheter-related and 46 were catheter-related. The most common catheter-related complications were premature loss of the catheter (18/46) and elevated blood urea nitrogen (BUN) and creatinine levels (12/46).

CONCLUSIONS

Due to the lack of comparative studies the (added) benefit of IA antibiotic infusion in the treatment of PJI remains uncertain. Based on the current evidence, we would advise against using it as a stand-alone treatment. A prospective randomized controlled trial using a well-described infusion protocol is needed to see if the potential benefits justify the increased costs and potential complications of this treatment modality.

What Is the Role of Local Antimicrobial Protection for One-Stage Revision for Peri-Prosthetic Hip Infection?

The aim of this review is to investigate the effective role of local antimicrobial protection for one-stage cemented and cementless hip revision surgery. Twelve studies reporting the results of cemented single-stage procedures with a minimum two-year follow-up were reviewed. When pooling together the data, no infection recurrence was observed on average in 83.3% of the patients (a range of 75.0% to 100%). Only two papers included patients treated without the use of antibiotic-loaded bone cement, with an average infection control of 95.9% in a total of 195 patients. This figure appears to be better than the 80.7% infection control obtained by pooling together all the remaining studies. Concerning cementless one-stage revision, a total of 17 studies, reporting on 521 patients, showed an average of 90.0% (range 56.8% to 100%) no infection recurrence at a minimum two-year follow-up. No comparative study investigated cementless revision with or without local antibacterial protection. The pooled data showed an average infection control of 86.7%, without the application of local antibacterials, compared to 90.1% to 100% with local antimicrobial protection, depending on the technology used. No statistical difference could be found, either considering local antibacterial strategies alone or pooled together. No side effects had been reported by any local antibacterial technique. Local antibacterial protection for one-stage hip revision surgery, although safe and largely performed in the clinical setting, appears to still rely mainly on experts' opinions with no prospective or comparative trial, hence no definitive conclusion can be drawn concerning its effective role in one-stage hip revision surgery.

Locally Delivered Antibiotics in Fracture-Related Infection

The prevention and treatment of fracture-related infections (FRIs) pose significant challenges in orthopaedic trauma care, with current practices predominantly relying on systemic antibiotic administration. However, locally delivered antibiotics achieve substantially higher tissue concentrations and minimise systemic side effects. Whilst extensively researched in periprosthetic joint infections (PJIs), the use of local delivery methods is increasingly prevalent in FRI prevention and treatment. Various local delivery methods such as powders, aqueous injections and carriers such as cement, bone graft, bioceramics, polymers and hydrogels have been explored. Biodegradable antibiotic carriers offer a promising alternative to non-absorbable carriers (i.e., cement), which necessitate surgical removal. There is good evidence for the use of local antibiotics in preventing and treating FRI, particularly in high-risk fractures or in treating more severe, resistant infections. Despite theoretical concerns, reports of adverse events in human studies are rare. To enhance our understanding of the safety and efficacy of these methods across various fracture patterns, further prospective randomised controlled trials are warranted. This article describes the current strategies and methodologies for FRI prevention and treatment and reviews the existing evidence base.

Efficacy and safety of intra-articular-only meropenem after one-stage revision for treating Escherichia coli-induced periprosthetic joint infection in a rat model

Aims

The optimum type of antibiotics and their administration route for treating Gram-negative (GN) periprosthetic joint infection (PJI) remain controversial. This study aimed to determine the GN bacterial species and antibacterial resistance rates related to clinical GN-PJI, and to determine the efficacy and safety of intra-articular (IA) antibiotic injection after one-stage revision in a GN pathogen-induced PJI rat model of total knee arthroplasty.

Methods

A total of 36 consecutive PJI patients who had been infected with GN bacteria between February 2015 and December 2021 were retrospectively recruited in order to analyze the GN bacterial species involvement and antibacterial resistance rates. Antibiotic susceptibility assays of the GN bacterial species were performed to screen for the most sensitive antibiotic, which was then used to treat the most common GN pathogen-induced PJI rat model. The rats were randomized either to a PJI control group or to three meropenem groups (intraperitoneal (IP), IA, and IP + IA groups). After two weeks of treatment, infection control level, the side effects, and the volume of antibiotic use were evaluated.

Results

Escherichia coli was the most common pathogen in GN-PJI, and meropenem was the most sensitive antibiotic. Serum inflammatory markers, weightbearing activity, and Rissing score were significantly improved by meropenem, especially in the IA and IP + IA groups ( p < 0.05). Meropenem in the IA group eradicated E. coli from soft-tissue, bone, and prosthetic surfaces, with the same effect as in the IP + IA group. Radiological results revealed that IA and IP + IA meropenem were effective at relieving bone damage. Haematoxylin and eosin staining also showed that IA and IP + IA meropenem improved synovial inflammation and bone destruction. No pathological changes in the main organs or abnormal serum markers were observed in any of the meropenem-treated rats. The IA group required the lowest amount of meropenem, followed by the IP and IP + IA groups.

Conclusion

IA-only meropenem with a two-week treatment course was effective and safe for PJI control following one-stage revision in a rat model, with less meropenem use.

Synovial vancomycin and meropenem concentrations in periprosthetic joint infection treated by single-stage revision combined with intra-articular infusion

Aims

We aimed to determine the concentrations of synovial vancomycin and meropenem in patients treated by single-stage revision combined with intra-articular infusion following periprosthetic joint infection (PJI), thereby validating this drug delivery approach.

Methods

We included 14 patients with PJI as noted in their medical records between November 2021 and August 2022, comprising eight hip and seven knee joint infections, with one patient experiencing bilateral knee infections. The patients underwent single-stage revision surgery, followed by intra-articular infusion of vancomycin and meropenem (50,000 µg/ml). Synovial fluid samples were collected to assess antibiotic concentrations using high-performance liquid chromatography.

Results

The peak concentrations of vancomycin and meropenem in the joint cavity were observed at one hour post-injection, with mean values of 14,933.9 µg/ml (SD 10,176.3) and 5,819.1 µg/ml (SD 6,029.8), respectively. The trough concentrations at 24 hours were 5,495.0 µg/ml (SD 2,360.5) for vancomycin and 186.4 µg/ml (SD 254.3) for meropenem. The half-life of vancomycin was 6 hours, while that of meropenem ranged between 2 and 3.5 hours. No significant adverse events related to the antibiotic administration were observed.

Conclusion

This method can achieve sustained high antibiotic concentrations within the joint space, exceeding the reported minimum biofilm eradication concentration. Our study highlights the remarkable effectiveness of intra-articular antibiotic infusion in delivering high intra-articular concentrations of antibiotics. The method provided sustained high antibiotic concentrations within the joint cavity, and no severe side-effects were observed. These findings offer evidence to improve clinical treatment strategies. However, further validation is required through studies with larger sample sizes and higher levels of evidence.

Safety Profile of Seven-Day Intra-articular Antibiotic Irrigation for the Treatment of Chronic Periprosthetic Joint Infection: A Prospective Randomized Phase II Comparative Study

BACKGROUND

Systemic intravenous antimicrobials yield poor outcomes during treatment of periprosthetic joint infection due to the inability to obtain minimum biofilm eradication concentrations. This study evaluated the safety of a novel method of optimized local delivery of intra-articular antibiotics (IAAs).

METHODS

This was a Phase II, multicenter, prospective randomized trial evaluating safety of a rapid (seven-day) two-stage exchange arthroplasty with IAA irrigation compared to standard two-stage exchange. The Experimental Group received irrigation using 80 mg tobramycin daily with a 2-hour soak, followed by hourly irrigation using 125 mg vancomycin with a 30-minute soak via an intramedullary irrigation device. The Control Group received an antibiotic-loaded cement spacer with vancomycin (average 8.4 g) and tobramycin (average 7.1 g, total 16 g antibiotics). Both groups received 12 weeks of systemic antibiotics following Stage 2. Safety measures included adverse events, peak vancomycin/tobramycin serum concentrations (Experimental Group), blood transfusion, and mortality. There were thirty-seven patients randomized to the Experimental Group and 39 to control. There was no difference in baseline demographics or comorbidities.

RESULTS

There were no antibiotic medication-related adverse events and 2 serious adverse events related to antibiotic instillation. Of 188 vancomycin peak measurements, 69% had detectable serum level concentrations, with all concentrations well below the maximum acceptable trough threshold of 20 μg/mL. Of the 103 tobramycin peak measurements, 45% had detectable levels, with all below the maximum acceptable peak threshold of 18 to 24 μg/mL. There was no difference in blood transfused per subject (Experimental: 655 mL versus Control: 792 mL; P = .4188). There were two (2) deaths in the Experimental Group and four (4) in the control.

CONCLUSIONS

The use of IAA is safe with minimal systemic antibiotic exposure. There was no difference in the rates or severity of serious adverse events between groups. Further research is being conducted to examine treatment efficacy.

The heavy burden and treatment challenges of fungal periprosthetic joint infection: a systematic review of 489 joints

BACKGROUND

Fungal periprosthetic joint infection (FPJI) is an infrequent but devastating complication that imposes a heavy burden on patients. At present, a consensus regarding the most optimal surgical option for patients with FPJI, the ideal duration of systemic antifungal treatment, and many other issues has not been reached.

METHODS

A comprehensive literature search was performed on the PubMed and Embase databases. The search criteria employed were as follows: (fungal OR candida OR mycotic) AND periprosthetic joint infection. Initially, the titles and abstracts were screened, and subsequently, studies deemed irrelevant or duplicative were eliminated. Following this, the complete texts of remaining articles were thoroughly examined. According to the inclusion and exclusion criteria, 489 joints in 24 articles were screened out. We further extracted the demographic characteristics (age, gender, body mass index, etc.), clinical presentation, fungal species, presence of bacterial coinfection, surgical methods, systemic and local antifungal therapy, and treatment outcomes. Subgroup data were analyzed according to fungal species and bacterial coinfection. Univariate logistic regression analysis was conducted to ascertain the risk factors associated with the infection recurrence.

RESULTS

A total of 506 fungi were identified within 489 joints. The most prevalent fungal species were Candida albicans (41.5%). Out of 247 joints (50.5%) presenting with concurrent fungal and bacterial infections. Among the initial surgical interventions, two-stage exchange was the most common (59.1%). The infection recurrence rates of DAIR, resection arthroplasty, two-stage, one-stage, and three-stage exchange were 81.4%, 53.1%, 47.7%, 35.0%, and 30%, respectively. The mean duration of systemic antifungal therapy was 12.8 weeks. The most common drugs used both in intravenous (55.9%) and oral therapy (84.0%) were fluconazole. The proportion of patients who used antifungal drugs after replantation (two-stage and three-stage) was 87.6%. 33.2% of cement spacer or fixed cement contained antifungal drugs, of which amphotericin B was the main choice (82.7%). FPJI caused by candida albicans (OR = 1.717, p = 0.041) and DAIR (OR = 8.433, p = 0.003) were risk factors for infection recurrence.

CONCLUSIONS

Two-stage exchange remains the most commonly used surgical approach. The reliability of one- and three-exchange needs further evaluation due to the small sample size. Antifungal-loaded cement spacers, and direct intra-articular injections of antimycotics after reimplatation should be strongly considered. Medication is not standardized but rather individualized according to microbiology and the status of patients.

Local Antibiotic Infusion in Periprosthetic Joint Infection Following Total Hip Arthroplasty

Local antibiotic infusion has emerged as a promising adjunctive therapy, delivering high concentrations of antibiotics directly to the infection site. This approach aims to enhance eradication of pathogens while minimizing systemic side effects associated with prolonged antibiotic use. This narrative review encompassed 10 articles focused on all three procedures of surgical intervention for periprosthetic joint injection (PJI) following total hip arthroplasty (THA): debridement, antibiotics, and implant retention (DAIR), single-stage revision arthroplasty, and two-stage revision arthroplasty. Recent studies report success rates ranging from 90 to 100% in patients undergoing DAIR, 82 to 100% in single-stage revision arthroplasty, and 80% in two-stage revision arthroplasty. The adjunctive use of local antibiotic infusion alongside surgical treatment for PJI following THA provides high success rates and is associated with low systemic complications, such as renal toxicity. Further research, particularly high-quality randomized controlled trials (RCTs), is warranted to validate and refine treatment protocols, ensuring consistent efficacy and safety.

Development of novel hybrid 3D-printed degradable artificial joints incorporating electrospun pharmaceutical- and growth factor-loaded nanofibers for small joint reconstruction

Small joint reconstruction remains challenging and can lead to prosthesis-related complications, mainly due to the suboptimal performance of the silicone materials used and adverse host reactions. In this study, we developed hybrid artificial joints using three-dimensional printing (3D printing) for polycaprolactone (PCL) and incorporated electrospun nanofibers loaded with drugs and biomolecules for small joint reconstruction. We evaluated the mechanical properties of the degradable joints and the drug discharge patterns of the nanofibers. Empirical data revealed that the 3D-printed PCL joints exhibited good mechanical and fatigue properties. The drug-eluting nanofibers sustainedly released teicoplanin, ceftazidime, and ketorolac in vitro for over 30, 19, and 30 days, respectively. Furthermore, the nanofibers released high levels of bone morphogenetic protein-2 and connective tissue growth factors for over 30 days. An in vivo animal test demonstrated that nanofiber-loaded joints released high concentrations of antibiotics and analgesics in a rabbit model for 28 days. The animals in the drug-loaded degradable joint group showed greater activity counts than those in the surgery-only group. The experimental data suggest that degradable joints with sustained release of drugs and biomolecules may be utilized in small joint arthroplasty.

Appropriate Duration of Antimicrobial Treatment for Prosthetic Joint Infections: A Narrative Review

Prosthetic joint infections are considered difficult to treat they needing aggressive surgery and long antimicrobial treatments. However, the exact duration of these therapies has been established empirically. In the last years, several studies have explored the possibility of reducing the length of treatment in this setting, with conflicting results. In this narrative review, we critically appraise the published evidence, considering the different surgical approaches (implant retention [DAIR] and one-step and two-step exchange procedures) separately. In patients managed with DAIR, usually treated for at least 12 weeks, a large, randomized trial failed to show that 6 weeks were non-inferior. However, another randomized clinical trial supports the use of 8 weeks, as long as the surgical conditions are favorable and antibiotics with good antibiofilm activity can be administered. In patients managed with a two-step exchange procedure, usually treated during 6 weeks, a randomized clinical trial showed the efficacy of a 4-week course of antimicrobials. Also, the use of local antibiotics may allow the use of even shorter treatments. Finally, in the case of one-step exchange procedures, there is a trend towards reducing the length of therapy, and the largest randomized clinical trial supports the use of 6 weeks of therapy.

Adjuvant intra-articular vancomycin for recalcitrant Staphylococcal prosthetic joint infections of the knee

OBJECTIVE

Chronic prosthetic joint infection patients who fail conventional two-stage revision surgery are an especially difficult to treat patient population. Consequently, the objective of this study was to investigate the safety and long-term effectiveness of adjuvant intra-articular vancomycin therapy in conjunction with two-stage revision knee arthroplasties for recalcitrant Staphylococcal prosthetic joint infections.

METHODS

This was an observational cohort study of twelve patients with recalcitrant Staphylococcal prosthetic joint infections of the knee which had failed previous revision surgeries. Each patient subsequently underwent two-stage revision with placement of Hickman catheters to deliver intra-articular vancomycin therapy. In addition, systemic antibiotic therapy was administered for 6 weeks, and long-term follow-up was evaluated then for 5 years.

RESULTS

Seventy-five percent of the cohort have had no recurrence of their infections at 5 years. Two patients formed fistulas requiring above the knee amputations, and three patients had acute kidney injury. All patients had maximum measurable serum vancomycin trough levels that ranged from 6.1 to 93.6 mcg/mL.

CONCLUSION

The aggressive protocol used in this cohort with repeat two-stage revision surgery, intra-articular vancomycin and systemic antibiotics was able to prevent recurrence of infection in most patients, but higher than expected rates of acute kidney injury were observed in this study. Therefore, while intra-articular vancomycin therapy may have some effectiveness in treating recalcitrant prosthetic joint infections, its ability to eradicate all bacterial niduses is unproven, and clinicians should be cognizant of potential adverse events that can occur with this therapy.

Two-dimensional liquid chromatography measurement of meropenem concentration in synovial fluid of patients with periprosthetic joint infection

Periprosthetic joint infection (PJI) is a catastrophic complication following joint replacement surgery. One potential treatment approach for PJI could be the combination of one-stage revision and intra-articular infusion of antibiotics. Meropenem is one of the commonly used intra-articular antibiotics in our institution. Determining the concentration of meropenem in the joint cavity could be crucial for optimizing its local application, effectively eradicating biofilm infection, and improving PJI treatment outcomes. In this study, we developed a simple, precise, and accurate method of two-dimensional liquid chromatography (2D-LC) for determining the concentration of meropenem in human synovial fluid. The method was then validated based on the guidelines of the Food and Drug Administration and the Chinese Pharmacopoeia. Meropenem showed good linearity in the range of 0.31-25.01 μg/mL (r ≥ .999). Selectivity, intra-day and inter-day precision and accuracy, extraction recovery, and stability validation results were all within the acceptance range. This method has been successfully applied to the determination of synovial fluid samples from PJI patients, providing a useful detection method for meropenem therapeutic drug monitoring (TDM) in PJI patients.

The use of intra-articular vancomycin is safe in primary hip and knee arthroplasty

Background

The use of a single dose of intra-articular antibiotic (IAA) has been reported in reducing the rate of prosthetic joint injection after total hip and knee arthroplasty. We examine the safety of IAA in primary hip and knee replacement surgery and the blood levels and joint fluid levels of vancomycin utilising this technique.

Methods

From August to October 2021, 68 patients undergoing primary total joint arthroplasty (THA & TKA) were given 1g vancomycin intra-articularly (IA)after closure of the fascia. All patients received 2g cefazolin intravenously (IV) 30 min prior to the procedure as is our standard prophylaxis, and 21 of the patients (IA + IV) were also administered an additional 1 gm vancomycin IV. Post-operative blood vancomycin, creatinine land eGFR level monitoring was performed d1 and d3. To determine the post-operative intra-articular vancomycin levels, surgical drain fluid was sampled at day 1 and 2, in 10 patients.

Results

All patients had serum vancomycin levels measured on day 1 and 3. In the group where vancomycin was injected after fascial closure, the average blood vancomycin level day 1 was 5.2 μg/ml (range 2.0-10.9) and day 3 was <1.4 μg/ml. The average pre-op creatinine levels were 69.4 μmol/L (56.1-82.6) compared to 70.2 μmol/L (57.0-83.4) on day 1 and 66.1 μmol/L (52.6-79.6) on day 3, (p = 0.663). The average pre-op eGFR levels (ml/min/1.73 m2) were 82.2 (76.0-88.3) compared to 81.7 (75.6-87.8) on day 1 and 83.0 (76.8-89.2) on day 3 (p = 0.736). Samples of joint fluid aspirated from surgical drains on day 1 and day 2 showed average vancomycin levels of 224 μg/ml and 51 μg/ml respectively, significantly higher than the MIC for Staph aureus.

Conclusions

The use of intra-articular vancomycin is safe in primary TJA, with no renal damage and delivers levels within the joint which are highly therapeutic for at least 48 h post injection.

Microbubble cavitation restores Staphylococcus aureus antibiotic susceptibility in vitro and in a septic arthritis model

Treatment failure in joint infections is associated with fibrinous, antibiotic-resistant, floating and tissue-associated Staphylococcus aureus aggregates formed in synovial fluid (SynF). We explore whether antibiotic activity could be increased against Staphylococcus aureus aggregates using ultrasound-triggered microbubble destruction (UTMD), in vitro and in a porcine model of septic arthritis. In vitro, when bacterially laden SynF is diluted, akin to the dilution achieved clinically with lavage and local injection of antibiotics, amikacin and ultrasound application result in increased bacterial metabolism, aggregate permeabilization, and a 4-5 log decrease in colony forming units, independent of microbubble destruction. Without SynF dilution, amikacin + UTMD does not increase antibiotic activity. Importantly, in the porcine model of septic arthritis, no bacteria are recovered from the SynF after treatment with amikacin and UTMD-ultrasound without UTMD is insufficient. Our data suggest that UTMD + antibiotics may serve as an important adjunct for the treatment of septic arthritis.

Local Antibiotic Delivery Options in Prosthetic Joint Infection

Prosthetic Joint Infection (PJI) causes significant morbidity and mortality for patients globally. Delivery of antibiotics to the site of infection has potential to improve the treatment outcomes and enhance biofilm eradication. These antibiotics can be delivered using an intra-articular catheter or combined with a carrier substance to enhance pharmacokinetic properties. Carrier options include non-resorbable polymethylmethacrylate (PMMA) bone cement and resorbable calcium sulphate, hydroxyapatite, bioactive glass, and hydrogels. PMMA allows for creation of structural spacers used in multi-stage revision procedures, however it requires subsequent removal and antibiotic compatibility and the levels delivered are variable. Calcium sulphate is the most researched resorbable carrier in PJI, but is associated with wound leakage and hypercalcaemia, and clinical evidence for its effectiveness remains at the early stage. Hydrogels provide a versatile combability with antibiotics and adjustable elution profiles, but clinical usage is currently limited. Novel anti-biofilm therapies include bacteriophages which have been used successfully in small case series.

Global Cluster Analysis and Network Visualization in Prosthetic Joint Infection: A Scientometric Mapping

OBJECTIVE

Prosthetic joint infection (PJI) is the main reason of failure of total joint arthroplasty (TJA). This study aimed to investigate the global trends and network visualization in research of PJI.

METHODS

Publications in PJI search during 1980-2022 were extracted from the Science Citation Index-Expanded of Web of Science Core Collection database (WoSCC). The source data was investigated and analyzed by bibliometric methodology. For network visualization, VOS viewer and R software was used to perform bibliographic coupling, co-citation, co-authorship and co-occurrence analysis and to predict the publication trends in PJI research.

RESULTS

There were 7288 articles included. The number of publications and relative research interests increased gradually per year globally. The USA made the highest contributions in the world and with the highest H-index and the most citations. Journal of Arthroplasty published the highest number of articles in this area. The Mayo Clinic, Thomas Jefferson University (Rothman Institute), Hospital Special Surgery and the Rush University were the most contributive institutions by network visualization. Included studies were divided into four clusters: bacterial pathogenic mechanism and antibacterial drugs study, TJA complications, risk factors and epidemiology of PJI, diagnosis of PJI, and revision surgical management. More articles in PJI could be published over the next few years.

CONCLUSION

The number of publications about PJI will be increasing dramatically based on the global trends and network visualization. The USA made the highest contributions in PJI. Diagnosis and revision management may be the next hot spots in this field.

One-stage revision using intra-articular carbapenem infusion effectively treats chronic periprosthetic joint infection caused by Gram-negative organisms

Gram-negative periprosthetic joint infection (PJI) has been poorly studied despite its rapidly increasing incidence. Treatment with one-stage revision using intra-articular (IA) infusion of antibiotics may offer a reasonable alternative with a distinct advantage of providing a means of delivering the drug in high concentrations. Carbapenems are regarded as the last line of defense against severe Gram-negative or polymicrobial infection. This study presents the results of one-stage revision using intra-articular carbapenem infusion for treating Gram-negative PJI, and analyzes the characteristics of bacteria distribution and drug sensitivity. We retrospectively reviewed 32 patients (22 hips and 11 knees) who underwent single-stage revision combined with IA carbapenem infusion between November 2013 and March 2020. The IA and intravenous (IV) carbapenem infusions were administered for a single Gram-negative infection, and IV vancomycin combined with IA carbapenems and vancomycin was applied for polymicrobial infection including Gram-negative bacteria. The bacterial community distribution, drug sensitivity, infection control rate, functional recovery, and complications were evaluated. Reinfection or death caused by PJI was regarded as a treatment failure. Gram-negative PJI was mainly caused by Escherichia coli (8/34), Enterobacter cloacae (7/34), and Klebsiella pneumoniae (5/34). Seven cases (7/32) involved polymicrobial PJIs. The resistance rates of penicillin, cephalosporin, quinolones, and sulfonamides were > 10%, and all penicillin and partial cephalosporins (first and second generation) were > 30%. Of 32 cases, treatment failed to eradicate infection in only three cases (9.4%), at a mean follow-up of 55.1 months (SD 25 to 90). The mean postoperative Harris Hip Score and Hospital for Special Surgery knee score at the most recent follow-up were 81 (62 to 91) and 79 (56 to 89), respectively. One patient developed a fistula, and another presented with a local rash on an infected joint. The use of IA carbapenem delivered alongside one-stage revision effectively controlled Gram-negative infection and obtained acceptable clinical outcomes with few complications. Notably, first- and second-generation cephalosporins and penicillin should be administrated with caution, due to a high incidence of resistance.

Experience Using Adjuvant Bacteriophage Therapy for the Treatment of 10 Recalcitrant Periprosthetic Joint Infections: A Case Series

Periprosthetic joint infections are a devastating complication of joint replacement surgery. One novel therapeutic that has potential to change the current treatment paradigm is bacteriophage therapy. Herein, we discuss our experiences with bacteriophage therapy for 10 recalcitrant periprosthetic joint infections and review the treatment protocols utilized to achieve successful outcomes.

The Impact of Exchanging Cerclage Fixation after Extended Trochanteric Osteotomy in Revision Total Hip Arthroplasty for Periprosthetic Joint Infection

BACKGROUND

An extended trochanteric osteotomy (ETO) is a powerful tool for femoral component revision. There is limited evidence that directly supports its use in the setting of a periprosthetic joint infection (PJI). Cerclage fixation raises the theoretical concern for persistent infection.

METHODS

Our institutional database included 76 ETOs for revision hip arthroplasty between January 1, 2008 and December 31, 2019. The cohort was divided based on indication for femoral component revision: PJI versus aseptic revision. The PJI group was subdivided based on second-stage exchange versus retention of initial cerclage fixation. Operative time, estimated blood loss, complications, and rate of repeat revision surgery were evaluated.

RESULTS

Forty-nine patients (64%) underwent revision for PJI and 27 patients (36%) underwent aseptic revision. There was no significant difference in operative times (P = .082), postoperative complications (P = .258), or rate of repeat revision surgery (P = .322) between groups. Of the 49 patients in the PJI group, 40 (82%) retained cerclage fixation while 9 (18%) had cerclage exchange. Cerclage exchange did not significantly impact operative time (P = .758), blood loss (P = .498), rate of repeat revision surgery (P = .302), or postoperative complications (P = .253) including infection (P = .639).

CONCLUSION

An ETO remains a powerful tool for femoral component removal, even in the presence of a PJI. A multi-institutional investigation would be required to validate observed trends toward better infection control with cerclage exchange. Cerclage exchange did not appear to increase operative time, blood loss, or postoperative complication rates.

Osteoarticular Mycoses

Osteoarticular mycoses are chronic debilitating infections that require extended courses of antifungal therapy and may warrant expert surgical intervention. As there has been no comprehensive review of these diseases, the International Consortium for Osteoarticular Mycoses prepared a definitive treatise for this important class of infections. Among the etiologies of osteoarticular mycoses are Candida spp., Aspergillus spp., Mucorales, dematiaceous fungi, non-Aspergillus hyaline molds, and endemic mycoses, including those caused by Histoplasma capsulatum, Blastomyces dermatitidis, and Coccidioides species. This review analyzes the history, epidemiology, pathogenesis, clinical manifestations, diagnostic approaches, inflammatory biomarkers, diagnostic imaging modalities, treatments, and outcomes of osteomyelitis and septic arthritis caused by these organisms. Candida osteomyelitis and Candida arthritis are associated with greater events of hematogenous dissemination than those of most other osteoarticular mycoses. Traumatic inoculation is more commonly associated with osteoarticular mycoses caused by Aspergillus and non-Aspergillus molds. Synovial fluid cultures are highly sensitive in the detection of Candida and Aspergillus arthritis. Relapsed infection, particularly in Candida arthritis, may develop in relation to an inadequate duration of therapy. Overall mortality reflects survival from disseminated infection and underlying host factors.

A review of current practices in periprosthetic joint infection debridement and revision arthroplasty

BACKGROUND

Periprosthetic joint infection remains a significant challenge for arthroplasty surgeons globally. Over the last few decades, there has been much advancement in terms of treatment and diagnosis, however, the fight rages on. As management of periprosthetic joint infections continues to evolve, it is critical to reflect back on current debridement practices to establish common ground as well as identify areas for future research and improvement. BODY: In order to understand the debridement techniques of periprosthetic joint infections, one must also understand how to diagnose a periprosthetic joint infection. Multiple definitions have been elucidated over the years with no single consensus established but rather sets of criteria. Once a diagnosis has been established the decision of debridement method becomes whether to proceed with single vs two-stage revision based on the probability of infection as well as individual patient factors. After much study, two-stage revision has emerged as the gold standard in the management of periprosthetic infections but single-stage remains prominent with further and further research.

CONCLUSION

Despite decades of data, there is no single treatment algorithm for periprosthetic joint infections and subsequent debridement technique. Our review touches on the goals of debridement while providing a perspective as to diagnosis and the particulars of how intraoperative factors such as intraarticular irrigation can play pivotal roles in infection eradication. By providing a perspective on current debridement practices, we hope to encourage future study and debate on how to address periprosthetic joint infections best.

Bacteriophage therapy for periprosthetic joint infections: Current limitations and research needed to advance this therapeutic

Bacteriophage therapy is a promising treatment for periprosthetic joint infections (PJIs), particularly given these agents have innate abilities to degrade the biofilm matrix and lyse bacteria within. However, many aspects of this therapy are poorly understood causing treatments to lack uniform effectiveness and reproducibility, which is in part a consequence of several inherent limitations to using bacteriophages to treat PJI. Herein, these limitations are discussed as are additional translational research that needs to be conducted to advance this therapeutic. These include determining if bacteria causing PJIs are polyclonal, consequences of bacteriophage attachment receptor phenotypic variations and ramifications of bacteriophage activity when bacteria interact with in vivo macromolecules. Only with the realization of the current limitations and subsequent knowledge gained from translational research will the potential of bacteriophages to reduce the morbidity and mortality in PJI be fully elucidated.

Effective single-stage revision using intra-articular antibiotic infusion after multiple failed surgery for periprosthetic joint infection : a mean seven years' follow-up

AIMS

Periprosthetic joint infections (PJIs) with prior multiple failed surgery for reinfection represent a huge challenge for surgeons because of poor vascular supply and biofilm formation. This study aims to determine the results of single-stage revision using intra-articular antibiotic infusion in treating this condition.

METHODS

A retrospective analysis included 78 PJI patients (29 hips; 49 knees) who had undergone multiple prior surgical interventions. Our cohort was treated with single-stage revision using a supplementary intra-articular antibiotic infusion. Of these 78 patients, 59 had undergone more than two prior failed debridement and implant retentions, 12 patients had a failed arthroplasty resection, three hips had previously undergone failed two-stage revision, and four had a failed one-stage revision before their single-stage revision. Previous failure was defined as infection recurrence requiring surgical intervention. Besides intravenous pathogen-sensitive agents, an intra-articular infusion of vancomycin, imipenem, or voriconazole was performed postoperatively. The antibiotic solution was soaked into the joint for 24 hours for a mean of 16 days (12 to 21), then extracted before next injection. Recurrence of infection and clinical outcomes were evaluated.

RESULTS

A total of 68 patients (87.1%) were free of infection at a mean follow-up time of 85 months (24 to 133). The seven-year infection-free survival was 87.6% (95% confidence interval (CI) 79.4 to 95.8). No significant difference in infection-free survival was observed between hip and knee PJIs (91.5% (95% CI 79.9 to 100) vs 84.7% (95% CI 73.1 to 96.3); p = 0.648). The mean postoperative Harris Hip Score was 76.1 points (63.2 to 92.4) and Hospital for Special Surgery score was 78. 2 (63.2 to 92.4) at the most recent assessment. Polymicrobial and fungal infections accounted for 14.1% (11/78) and 9.0% (7/78) of all cases, respectively.

CONCLUSION

Single-stage revision with intra-articular antibiotic infusion can provide high antibiotic concentration in synovial fluid, thereby overcoming reduced vascular supply and biofilm formation. This supplementary route of administration may be a viable option in treating PJI after multiple failed prior surgeries for reinfection. Cite this article: Bone Joint J 2022;104-B(7):867-874.

Intra-articular versus systemic vancomycin for the treatment of periprosthetic joint infection after debridement and spacer implantation in a rat model

Aims

Treatment outcomes for methicillin-resistant Staphylococcus aureus (MRSA) periprosthetic joint infection (PJI) using systemic vancomycin and antibacterial cement spacers during two-stage revision arthroplasty remain unsatisfactory. This study explored the efficacy and safety of intra-articular vancomycin injections for PJI control after debridement and cement spacer implantation in a rat model.

Methods

Total knee arthroplasty (TKA), MRSA inoculation, debridement, and vancomycin-spacer implantation were performed successively in rats to mimic first-stage PJI during the two-stage revision arthroplasty procedure. Vancomycin was administered intraperitoneally or intra-articularly for two weeks to control the infection after debridement and spacer implantation.

Results

Rats receiving intra-articular vancomycin showed the best outcomes among the four treatment groups, with negative bacterial cultures, increased weight gain, increased capacity for weightbearing activities, increased residual bone volume preservation, and reduced inflammatory reactions in the joint tissues, indicating MRSA eradication in the knee. The vancomycin-spacer and/or systemic vancomycin failed to eliminate the MRSA infections following a two-week antibiotic course. Serum vancomycin levels did not reach nephrotoxic levels in any group. Mild renal histopathological changes, without changes in serum creatinine levels, were observed in the intraperitoneal vancomycin group compared with the intra-articular vancomycin group, but no changes in hepatic structure or serum alanine aminotransferase or aspartate aminotransferase levels were observed. No local complications were observed, such as sinus tract or non-healing surgical incisions.

Conclusion

Intra-articular vancomycin injection was effective and safe for PJI control following debridement and spacer implantation in a rat model during two-stage revision arthroplasties, with better outcomes than systemic vancomycin administration.

Cite this article: Bone Joint Res 2022;11(6):371–385.

A Platelet-Rich Plasma-Derived Biologic Clears Staphylococcus aureus Biofilms While Mitigating Cartilage Degeneration and Joint Inflammation in a Clinically Relevant Large Animal Infectious Arthritis Model

The leading cause of treatment failure in Staphylococcus aureus infections is the development of biofilms. Biofilms are highly tolerant to conventional antibiotics which were developed against planktonic cells. Consequently, there is a lack of antibiofilm agents in the antibiotic development pipeline. To address this problem, we developed a platelet-rich plasma (PRP)-derived biologic, termed BIO-PLY (for the BIOactive fraction of Platelet-rich plasma LYsate) which has potent in vitro bactericidal activity against S. aureus synovial fluid free-floating biofilm aggregates. Additional in vitro studies using equine synoviocytes and chondrocytes showed that BIO-PLY protected these cells of the joint from inflammation. The goal of this study was to test BIO-PLY for in vivo efficacy using an equine model of infectious arthritis. We found that horses experimentally infected with S. aureus and subsequently treated with BIO-PLY combined with the antibiotic amikacin (AMK) had decreased bacterial concentrations within both synovial fluid and synovial tissue and exhibited lower systemic and local inflammatory scores compared to horses treated with AMK alone. Most importantly, AMK+BIO-PLY treatment reduced the loss of infection-associated cartilage proteoglycan content in articular cartilage and decreased synovial tissue fibrosis and inflammation. Our results demonstrate the in vivo efficacy of AMK+BIO-PLY and represents a new approach to restore and potentiate antimicrobial activity against synovial fluid biofilms.

A novel treatment strategy using continuous local antibiotic perfusion: A case series study of a refractory infection caused by hypervirulent Klebsiella pneumoniae

BACKGROUND

Conventional topical antimicrobial therapy cannot maintain a constant local concentration, resulting in uncontrolled infection and complications. We propose continuous local antibiotic perfusion (CLAP), which can maintain a constant appropriate local antibiotic concentration for a long time with less invasiveness and complications. CLAP is clearly different from traditional treatment because it uses negative pressure to direct the continuously infused antibiotic solution to the center of infection and excrete it outside the body. This study aimed to demonstrate the effectiveness of CLAP by presenting cases in which even refractory bone and soft-tissue infections caused by the hypervirulent Klebsiella pneumoniae (hvKp) could be cured without significant tissue loss and dysfunction.

METHODS

This study is a case series in which four patients with limb infection due to hvKp were treated by CLAP. hvKp was defined by a positive string test. The therapy included intra-soft-tissue antibiotic perfusion and intramedullary antibiotic perfusion. Gentamicin (60 mg/50 cc) was infused continuously through dual-lumen tubes and bone marrow needles at low-flow rates (2 mL/h). Negative pressure was used to collect the antimicrobial solution and eliminate the dead space.

RESULTS

The infection was controlled in all four patients after a mean period of 44.3 days. The mean maximum blood concentration of gentamicin was 1.6 μg/dL, and no cases of renal dysfunction or ototoxicity occurred. After CLAP, wound closure was required in two patients and iliac bone grafting was required in one patient. As sequelae, there were one case of osteoarthritis and one case of higher brain dysfunction due to hypoxia.

CONCLUSIONS

Our results suggest that intractable hvKp infections can be controlled by CLAP. CLAP may give us the option to directly control local infections with less systemic complications. Therefore, it is considered a valuable treatment for further basic and clinical research, and this research report may be a first step.

Effective Treatment of Single-Stage Revision Using Intra-Articular Antibiotic Infusion for Polymicrobial Periprosthetic Joint Infection

BACKGROUND

The treatment of polymicrobial periprosthetic joint infection (PJI) confronted distinct challenges. No reports have assessed the efficacy of local antibiotic delivery combined with 1-stage exchange in polymicrobial PJI.

METHODS

Between January 2013 and December 2018, we retrospectively analyzed the data of 126 patients, including 19 polymicrobial PJIs and 107 monomicrobial PJIs, who underwent single-stage revision using intra-articular antibiotic infusion. The risk factors, microbiology, infection control rate, and clinical outcomes were compared between the 2 groups.

RESULTS

Higher body mass index, presence of a sinus tract, and prior revisions were the risk factors for polymicrobial PJI. Isolation of Staphylococcus epidermidis, Streptococcus, Enterococcus, and Gram-negative pathogens was highly associated with polymicrobial PJI. Of the 19 polymicrobial PJIs, only 2 patients occurred infection recurrence, which is similar with the result of 6 of 107 patients in the monomicrobial PJI (P = .225). The Harris Hip Score of the polymicrobial group showed no difference from that of the monomicrobial group (78 vs 80; P = .181). Nevertheless, the polymicrobial group exhibited inferior Hospital for Special Surgery knee score relative to the monomicrobial group (77 vs 79; P = .017).

CONCLUSION

With rational and targeted use of antibiotics, single-stage revision can effectively control polymicrobial infections, and achieve favorable outcomes similar to that in monomicrobial patients. However, this regimen is still needed to be further confirmed, especially in the infections with different microbial species simultaneously. Additionally, obese patients with a sinus tract and those who had prior revisions had a greater risk of polymicrobial PJI.

Intra-wound vancomycin powder for the eradication of periprosthetic joint infection after debridement and implant exchange: experimental study in a rat model

Background

Intra-wound vancomycin powder (VP) has been used in clinical practice to prevent periprosthetic joint infection (PJI) after primary knee/hip arthroplasty. The role of intra-wound VP in the setting of debridement and implant exchange after PJI remains undefined. This study aimed to explore the efficacy and safety of intra-wound VP in the control of methicillin-resistant S. aureus (MRSA) infection after debridement and implant exchange.

Methods

PJI modeling by knee prosthesis implantation and MRSA inoculation, debridement and implant exchange were performed in Wistar rats successively to mimic the one-stage exchange arthroplasty of PJI patients. Two weeks of systemic vancomycin (SV) or/and intraoperative intra-wound VP of single dosage were applied after revision surgery.

Results

No post-surgery deaths, incision complications and signs of drug toxicity were observed. The microbial counts of SV or intra-wound VP group were significantly reduced compared with the control group, while bacteria were still detected on the bone, soft-tissue and prosthesis. The elimination of bacterial counts, along with improvement of tissue inflammation and serum inflammatory markers, were observed in the rats with SV plus intra-wound VP. Serum levels of vancomycin in all groups were lower than that of causing nephrotoxicity, while no statistic difference was observed in the serum biochemical marker among the groups.

Conclusions

Intra-wound VP is effective after debridement and implant exchange in our current rat PJI model. Neither SV nor intra-wound VP alone could eradicate the bacteria within a two-weeks treatment course, while SV plus intra-wound VP could eliminate the MRSA infection, without notable hepatic or renal toxicity and any incision complications.

Intra-articular administration of antibiotics in horses: Justifications, risks, reconsideration of use and outcomes

Antibiotics have been injected intra-articularly by equine veterinarians for decades, either prophylactically when other drugs are administered for osteoarthritis or therapeutically to treat septic arthritis. This route of administration has also more recently gained attention in human orthopaedic clinical practice, particularly as an alternative to systemic antibiotic administration to treat infections following prosthetic arthroplasty. While the rationale for injecting antibiotics intra-articularly has been largely focused on achieving high local drug concentrations, there has been relatively little focus on pharmacokinetic parameters of antibiotics administered by this route, or on the potential for local toxicity. The increasing incidence of antibiotic resistance in veterinary and human medicine prompts reconsideration of off-label antibiotic usage and evaluation of evidence-based dosing strategies. The purpose of this review was to summarise the current literature describing intra-articular antibiotic usage, including specific studies where pharmacokinetics, potential safety and toxicity have been evaluated. This review will advance practitioners' understanding of the use of intra-articularly administered antibiotics, including the overall pros and cons of the approach.

Local Application of Vancomycin in One-Stage Revision of Prosthetic Joint Infection Caused by Methicillin-Resistant Staphylococcus aureus

The rate of eradication of periprosthetic joint infection (PJI) caused by methicillin-resistant Staphylococcus aureus (MRSA) is still not satisfactory with systemic vancomycin administration after one-stage revision arthroplasty. This study aimed to explore the effectiveness and safety of intraarticular (IA) injection of vancomycin in the control of MRSA PJI after one-stage revision surgery in a rat model. Two weeks of intraperitoneal (IP) and/or IA injection of vancomycin was used to control the infection after one-stage revision surgery. The MRSA PJI rats treated with IA injection of vancomycin showed better outcomes in skin temperature, bacterial counts, biofilm on the prosthesis, serum α₁-acid glycoprotein levels, residual bone volume, and inflammatory reaction in the joint tissue, compared with those treated with IP vancomycin, while the rats treated with IP and IA administration showed the best outcomes. However, only the IP and IA administration of vancomycin could eradicate MRSA. Minimal changes in renal pathology were observed in the IP and IP plus IA groups but not in the IA group, while no obvious changes were observed in the liver or in levels of serum markers, including creatinine, alanine aminotransferase, and aspartate aminotransferase. Therefore, IA use of vancomycin is effective and safe in the MRSA PJI rat model and is better than systemic administration, while IA and systemic vancomycin treatment could eradicate the infection with a 2-week treatment course.

Serum and Synovial Vancomycin Concentrations in Patients with Prosthetic Joint Infection after Intra-articular Infusion

BACKGROUND AND OBJECTIVES

Vancomycin is one of the most commonly used antibiotics for intra-articular (IA) infusion in the treatment of prosthetic joint infection (PJI). This study aimed to preliminarily investigate the serum and synovial vancomycin concentrations in patients with PJI after IA infusion.

METHODS

In total, 16 patients who developed PJI were enrolled in this study; 14 of the patients were treated with IA infusion of vancomycin postoperatively, while the other 2 patients received intravenous (IV) infusion of vancomycin alone. Chemiluminescent immunoassay assay (CLIA) and high-performance liquid chromatography (HPLC) were used to determine the serum and synovial vancomycin concentrations, respectively.

RESULTS

Administration of vancomycin 0.5 g once daily (qd) IA maintained a high vancomycin trough concentration in synovial fluid before the next IA dose, regardless of whether it was given in combination with IV administration. The combination vancomycin 0.5 g qd IA + vancomycin 1 g every 12 h (q12h) IV yielded relatively good trough concentrations of vancomycin in both serum and synovial fluid. The mean trough serum vancomycin concentration of patients who used vancomycin 1 g q12h IV therapy was above 10 μg/mL; however, no vancomycin was detected in their synovial fluid.

CONCLUSIONS

The rational use of IA vancomycin infusion may help to achieve effective therapeutic concentrations of vancomycin in the serum and synovial fluid of patients with PJI.

Local Vancomycin Concentrations after Intra-articular Injection into the Knee Joint: An Experimental Porcine Study

Intra-articular injection of vancomycin may be an important antimicrobial prophylactic supplement to systemic administration in the prevention of prosthetic joint infections. In eight female pigs, 500 mg of diluted vancomycin was given by intra-articular injection into the knee joint. Microdialysis was used for dense sampling of vancomycin concentrations over 12 hours in the synovial fluid of the knee joint, and in the adjacent femoral and tibial cancellous bone and subcutaneous tissue. Venous blood samples were obtained as reference. The mean (standard deviation [SD]) peak drug concentration of vancomycin in the synovial fluid of the knee joint was 5,277 (5,668) μg/mL. Only one pig failed to reach a peak drug concentration above 1,000 μg/mL. The concentration remained high throughout the sampling interval with a mean (SD) concentration of 337 (259) μg/mL after 690 minutes. For all extraarticular compartments, the pharmacokinetic parameters (area under the concentration time-curve, peak drug concentration, and time to peak drug concentration) were comparable. The highest extraarticular mean (SD) peak drug concentration of 4.4 (2.3) μg/mL was found in subcutaneous tissue. An intra-articular injection of 500 mg diluted vancomycin was found to provide significant prophylactic mean concentrations for at least 12 hours in the synovial fluid of the knee joint. Correspondingly, the adjacent tissue and plasma concentrations were low but remained stable, signifying low risk of systemic toxic side effects and a slow release or uptake from the synovium to the systemic circulation.

Debridement, antibiotics, and implant retention combined with direct intra-articular antibiotic infusion in patients with acute hematogenous periprosthetic joint infection of the knee

Background

Debridement, antibiotics, and implant retention (DAIR) is the recommended treatment for acute hematogenous periprosthetic joint infection (PJI) after total knee arthroplasty (TKA). However, DAIR is associated with a high percentage of unsuccessful outcomes. Since 2007, direct intra-articular antibiotic infusion, which can provide a high concentration of intra-articular antibiotic, has been used in combination with DAIR to improve treatment outcomes among patients in our institution. This study aimed to assess the outcomes of DAIR combined with direct intra-articular antibiotic infusion in patients who presented with acute hematogenous PJI after TKA.

Methods

We reviewed the data of all patients diagnosed with acute hematogenous PJI after primary TKA (from 2008 to 2015) who received DAIR combined with direct intra-articular antibiotic infusion.

Results

In total, 15 knees in 12 patients were semi-urgently treated with this method. The mean follow-up time was 93.3 (minimum: 56) months, and the longest follow-up time was 11 years. Two patients (n = 3 knees) had a well-functioning, non-infected prosthesis 6 and 10 years after the procedure. Two patients (n = 2 knees) had re-infection 2 and 5 years after surgery, and they required two-stage revision. None of the patients were lost to follow-up. Finally, 13 (86.6%) of 15 infected knees were successfully treated with this method.

Conclusions

DAIR combined with direct intra-articular antibiotic infusion is an effective treatment for acute hematogenous PJI after TKA.

Evaluation of Intra-Articular Amikacin Administration in an Equine Non-inflammatory Joint Model to Identify Effective Bactericidal Concentrations While Minimizing Cytotoxicity

Septic arthritis causes significant morbidity and mortality in veterinary and human clinical practice and is increasingly complicated by multidrug-resistant infections. Intra-articular (IA) antibiotic administration achieves high local drug concentrations but is considered off-label usage, and appropriate doses have not been defined. Using an equine joint model, we investigated the effects of amikacin injected at three different doses (500, 125, and 31.25 mg) on the immune and cartilage responses in tibiotarsal joints. Synovial fluid (SF) was sampled at multiple time points over 24 h, the cell counts determined, and amikacin concentrations measured by liquid chromatography-mass spectrometry. Cytokine concentrations and collagen degradation products in SF were measured by ELISA and multiplex immunoassays. The mean amikacin concentrations in SF were greater than or equal to the minimum inhibitory concentration (MIC) (0.004 mg/ml) for most common equine joint pathogens at all time points tested to 24 h for all three amikacin doses evaluated. The inflammatory cytokines tumor necrosis factor-alpha (TNF-α) and interleukin-1 beta (IL-1β) increased significantly in SF in the highest amikacin dose group, despite the fact that increases in SF cell counts were not observed. Similarly, the biomarkers of cartilage type II collagen cleavage (C2C and C12C) were increased in SF following amikacin injection. Mechanistically, we further demonstrated using in vitro studies that chondrocytes and synoviocytes killed by exposure to amikacin underwent apoptotic cell death and were phagocytosed by macrophages in a non-inflammatory process resembling efferocytosis. Neutrophils and T cells were susceptible to amikacin cytotoxicity at clinically relevant doses, which may result in blunting of cellular inflammatory responses in SF and account for the lack of increase in total nucleated cell counts following amikacin injection. In summary, decisions on whether to inject cytotoxic antibiotics such as aminoglycosides intra-articularly and what doses to use should take into account the potential harm that antibiotics may cause and consider lower doses than those previously reported in equine practice.

Susceptibility of canine chondrocytes and synoviocytes to antibiotic cytotoxicity in vitro

OBJECTIVE

To evaluate relative cytotoxicity of antibiotics to normal canine joint tissues in vitro.

STUDY DESIGN

Experimental in vitro study.

SAMPLE POPULATION

Chondrocytes and synoviocytes (three dogs); cartilage explants (three dogs); six dogs total.

METHODS

Chondrocytes and synoviocytes from normal femoropatellar joints of three dogs were plated on 24-well plates (50 000 cells/cm² , triplicate, 48 hours) and exposed to antibiotics (ampicillin sulbactam, vancomycin, cefazolin, ceftazidime, amikacin, enrofloxacin; 0.39-25 mg/mL, 24 hours). Viability was assessed by using trypan blue dye exclusion. Antibiotic concentrations at which 50% cell death occurred (half-maximal inhibitory concentration) were determined to rank antibiotics for relative cytotoxicity. Occurrence of caspase-3 expression after antibiotic exposure was assessed as an indication of apoptosis induction. Cartilage explants from three different dogs were minced and exposed to antibiotics (amikacin, ceftazidime, cefazolin, enrofloxacin; 5 mg/mL, 72 hours). Live/dead staining was performed, and fluorescence was visualized by using confocal microscopy. Percentage of live vs dead cells was quantitated.

RESULTS

Viability of chondrocytes and synoviocytes decreased with increasing antibiotic concentrations. Half-maximal inhibitory concentrations were determined for synoviocytes (vancomycin 13.77, ampicillin sulbactam 3.07, amikacin 2.26, ceftazidime 1.62, cefazolin 1.48, enrofloxacin 1.25 mg/mL) and chondrocytes (vancomycin 8.65, ampicillin sulbactam 8.63, ceftazidime 3.16, amikacin 2.74, cefazolin 1.67, enrofloxacin 0.78 mg/mL). Caspase-3 expression was upregulated, providing evidence that apoptotic pathways were active in cell death.

CONCLUSION

Half-maximal inhibitory concentration data provided evidence of lower toxicity of vancomycin and ampicillin sulbactam to joint tissues in vitro.

CLINICAL SIGNIFICANCE

These results provide evidence to justify future in vitro work with osteoarthritic joint tissues and in vivo clinical trials to evaluate safety and efficacy of intra-articular antibiotics to treat dogs with septic arthritis.

Systematic review of single stage revision for prosthetic joint infection

While advanced technology, increased medical knowledge and improved surgical technique has improved patient outcomes in total joint arthroplasty, prosthetic joint infection still remains one of the leading causes of increased healthcare costs, medical resources and societal burdens in orthopaedic care. Two stage arthroplasty revision remains the gold standard for treatment of prosthetic joint infection. Proponents of single stage revision arthroplasty for infection argue that it results in lower healthcare costs while improving patient reported functional outcomes and with equivalent success rates. Here we review the history of single stage revision arthroplasty, discuss the key principles, highlight the indications and contraindications, and review the reported outcomes with a focus on future developments of single stage revision arthroplasty for hip and knee periprosthetic joint infections.

Antibiotic Stewardship for Total Joint Arthroplasty in 2020

Projections indicate an increase in primary and revision total joint arthroplasties (TJAs). Periprosthetic joint infections (PJIs) are one of the most common and devastating causes of failure after TJA. Perioperative administration of systemic and/or local antibiotics is used for both prophylaxis and treatment of PJI. Antibiotic stewardship is a term that has been met with clinical acceptance and success in other specialties of medicine. Identifying antibiotic best practice use in the fight against PJI is limited by studies that are extremely heterogeneous in their design. Variations in studies include antibiotic selection and duration, surgical débridement steps, type of antibiotic delivery (intra-articular, local, intravenous, and prolonged oral), mix of primary and revision surgery cohorts, both hip and knee cohorts, infecting organisms, and definitions of treatment success/failure. This review highlights the current challenges of antibiotic stewardship in TJA.

Combinational therapy with antibiotics and antibiotic-loaded adipose-derived stem cells reduce abscess formation in implant-related infection in rats

Implant-related infection is difficult to treat without extended antibiotic courses. However, the long-term use of antibiotics has led to the development of multidrug- and methicillin-resistant Staphylococcusaureus. Thus, alternatives to conventional antibiotic therapy are needed. Recently, mesenchymal stem cells have been shown to have antimicrobial properties. This study aimed to evaluate the antimicrobial activity and therapeutic effect of local treatment with antibiotic-loaded adipose-derived stem cells (ADSCs) plus an antibiotic in a rat implant-associated infection model. Liquid chromatography/tandem mass spectrometry revealed that ADSCs cultured in the presence of ciprofloxacin for 24 h showed time-dependent antibiotic loading. Next, we studied the therapeutic effects of ADSCs and ciprofloxacin alone or in combination in an implant-related infection rat model. The therapeutic effects of ADSCs plus antibiotics, antibiotics, and ADSCs were compared with no treatment as a control. Rats treated with ADSCs plus ciprofloxacin had the lowest modified osteomyelitis scores, abscess formation, and bacterial burden on the implant among all groups (P < 0.05). Thus, local treatment with ADSCs plus an antibiotic has an antimicrobial effect in implant-related infection and decrease abscess formation. Thus, our findings indicate that local administration of ADSCs with antibiotics represents a novel treatment strategy for implant-associated osteomyelitis.

Use of in vitro assays to identify antibiotics that are cytotoxic to normal equine chondrocytes and synovial cells

BACKGROUND

Intra-articular (IA) antibiotic usage is prevalent in equine practice. However, recent emergence of antimicrobial resistance prompts re-evaluation of antibiotic selection, particularly when used prophylactically. Furthermore, many commonly used antibiotics exert direct cytotoxicity to equine cells, and appropriate IA doses have not been defined.

OBJECTIVES

To screen antibiotics in vitro as an initial assessment of cytotoxicity against normal equine joint cells in monolayer culture and explant tissues.

STUDY DESIGN

In vitro experimental study.

METHODS

Chondrocytes and synovial cells were harvested from three horses and plated on 24-well plates (100 000 cells/wells in triplicate) for 48 hours prior to addition of antibiotics. Joint cells were exposed to antibiotics (n = 15) at various doses (25-0.39 mg/mL in complete DMEM media) for 24 hours and viability was assessed by trypan blue dye exclusion. The half maximal inhibitory concentration (IC50) was determined for each antibiotic. Cartilage explants were obtained from 3 horses, minced and exposed to antibiotics (n = 5) for 72 hours. Live/dead staining was performed, and fluorescence was visualised using Olympus IX83 spinning disk confocal microscope. Percentage of live vs dead cells was quantified.

RESULTS

Antibiotics from different antimicrobial classes expressed dose-dependent but variable cytotoxicity to equine joint cells in vitro. Aminoglycosides and doxycycline had the lowest IC50 (most toxic). Ampicillin sulbactam, imipenem, tobramycin, ceftiofur sodium and amoxicillin had IC50 > 25 mg/mL for at least one cell line, representing potentially less cytotoxic alternatives.

MAIN LIMITATIONS

Further studies are necessary to extrapolate these in vitro data results to the in vivo joint environment.

CONCLUSIONS

Targeted IA antibiotic therapy would involve selection of the safest antibiotics (highest IC50) with efficacy based on bacterial culture/sensitivity. Antimicrobial selection and evidence-based dosing may minimise damage to native articular cartilage and synovial cells and development of antimicrobial resistance when IA antibiotics are used in equine practice.

New developments and future challenges in prevention, diagnosis, and treatment of prosthetic joint infection

Prosthetic joint infection (PJI) is a devastating complication that results in substantial costs to society and patient morbidity. Advancements in our knowledge of this condition have focused on prevention, diagnosis, and treatment, in order to reduce rates of PJI and improve patient outcomes. Preventive measures such as optimization of patient comorbidities, and perioperative antibiotic usage are intensive areas of current clinical research to reduce the rate of PJI. Improved diagnostic tests such as synovial fluid (SF) α-defensin enzyme-linked immunosorbent assay, and nucleic acid-based tests for serum, SF, and tissue cultures, have improved diagnostic accuracy and organism identification. Increasing the diversity of available antibiotic therapy, immunotherapy, and alternative implant coatings remain promising treatments to improve infection eradication in the setting of PJI.

Effective treatment of single-stage revision using intra-articular antibiotic infusion for culture-negative prosthetic joint infection

AIMS

In the absence of an identified organism, single-stage revision is contraindicated in prosthetic joint infection (PJI). However, no studies have examined the use of intra-articular antibiotics in combination with single-stage revision in these cases. In this study, we present the results of single-stage revision using intra-articular antibiotic infusion for treating culture-negative (CN) PJI.

METHODS

A retrospective analysis between 2009 and 2016 included 51 patients with CN PJI who underwent single-stage revision using intra-articular antibiotic infusion; these were compared with 192 culture-positive (CP) patients. CN patients were treated according to a protocol including intravenous vancomycin and a direct intra-articular infusion of imipenem and vancomycin alternately used in the morning and afternoon. In the CP patients, pathogen-sensitive intravenous (IV) antibiotics were administered for a mean of 16 days (12 to 21), and for resistant cases, additional intra-articular antibiotics were used. The infection healing rate, Harris Hip Score (HHS), and Hospital for Special Surgery (HSS) knee score were compared between CN and CP groups.

RESULTS

Of 51 CN patients, 46 (90.2%) required no additional medical treatment for recurrent infection at a mean of 53.2 months (24 to 72) of follow-up. Impaired kidney function occurred in two patients, and one patient had a local skin rash. No significant difference in the infection control rate was observed between CN and CP PJIs (90.2% (46/51) versus 94.3% (181/192); p = 0.297). The HHS of the CN group showed no substantial difference from that of CP cases (79 versus 81; p = 0.359). However, the CN group showed a mean HSS inferior to that of the CP group (76 versus 80; p = 0.027).

CONCLUSION

Single-stage revision with direct intra-articular antibiotic infusion can be effective in treating CN PJI, and can achieve an infection control rate similar to that in CP patients. However, in view of systemic toxicity, local adverse reactions, and higher costs, additional strong evidence is needed to verify these treatment regimens. Cite this article: Bone Joint J 2020;102-B(3):336-344.

Partial implant retention in two-stage exchange for chronic infected total hip arthroplasty

BACKGROUND

The efficacy of partial retention of well-fixed components during two-stage exchange for chronic total hip arthroplasty (THA) infection has remained unknown.

METHODS

A total of 14 patients with chronic infected THA were treated with damage control two-stage revision, including selective retention of the well-fixed femoral or acetabular component, aggressive debridement, antibiotic-laden cement spacer, antibiotic therapy, and delayed reimplantation. Indications for this treatment included chronic infected THAs with ingrown femoral or acetabular component and positive microbial growth with sensitive antibiotics. We excluded patients with acute infection; negative microbial growth; positive pathogen with high-virulence bacterial infections and multiple drug-resistant bacteria such as methicillin-resistant Staphylococcus aureus, fungi, and Mycobacterium tuberculosis; sinus formation; a prior failure for periprosthetic joint infection (PJI) treatment; and obvious bone resorption in both femoral and acetabulum side. During the study period, this represented 3.3% (14/425) of the patients treated for infected THA. Minimum follow-up was three  years. None of the 14 patients in this series were lost to follow-up. Successful treatment was defined according to a modified Delphi-based international multidisciplinary consensus.

RESULTS

No repeated debridement and recurrence of infection occurred during the study period; no patient need chronic antibiotic suppression. Successful treatment of chronic PJI was achieved in all patients. Despite the high peri-operative complication rate, no severe consequences were observed. The mean Harris Hip Score was 86 (range, 82-92; SD, 3.3).

CONCLUSIONS

The selective partial implant retention two-stage revision for chronic PJI may be a treatment option in properly selected patients with low virulence bugs.