Acute Kidney Injury With Tobramycin-Impregnated Bone Cement Spacers in Prosthetic Joint Infections

A Case of Severe Acute Kidney Injury Due to an Antibiotic-Loaded Cement Spacer for Infected Knee Arthroplasty

The treatment for periprosthetic joint infection frequently involves the placement of a high-dose antibiotic-loaded bone cement spacer (ALCS) into the debrided joint. Typical antibiotics in the spacer include aminoglycosides and vancomycin. It has been believed that systemic absorption of intraarticular antibiotics would be low, and early experience suggested that the risk of acute kidney injury (AKI) from ALCS was minimal. However, recent case reports and case series have suggested a risk of AKI owing to antibiotic absorption, though confounding factors are common. We report a case of severe AKI requiring hemodialysis with extremely high systemic tobramycin levels after the placement of an ALCS with increased dosing of antibiotics after previous failure to resolve a periprosthetic joint infection with a prior ALCS. There was no concomitant use of intravenous nephrotoxic antibiotics, nor were there other confounding factors. Despite dialysis, the patient needed urgent removal of the ALCS to control tobramycin levels, with subsequent resolution of the AKI. This case highlights the potentially serious nephrotoxicity of ALCSs, the importance of antibiotic type and dosing, and the value of close monitoring after ALCS placement, especially in a patient with chronic kidney disease.

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.

Trends and Epidemiology in Revision Total Knee Arthroplasty: A Large Database Study

BACKGROUND

As the volume of primary total knee arthroplasty (TKA) continues to grow, the clinical and financial burden of revision total knee arthroplasty (rTKA) is expected to increase. The purpose of this investigation was to characterize contemporary indications and complications for rTKA.

METHODS

Patients undergoing rTKA between 2010 and 2021 were identified within an administrative claims database. Adjusted rTKA incidence was calculated by dividing the annual rTKA volume by the annual primary TKA and multiplying by 100,000. Mann-Kendall trend tests were utilized to trend revision volume, etiology, 90-day postoperative complications, and patient demographics.

RESULTS

A total of 397,367 rTKA were identified over our study period, of which 287,492 (72.4%) had coding regarding revision etiology. The volume of annual rTKA (31,091 to 33,850; P = 0.451) did not change over the study period. The adjusted incidence of rTKA decreased (25,568.3 to 19,272.2 per 100,000 annual TKA; P = 0.011). The leading causes of revision TKA were infection (21.2%), aseptic implant loosening (19.3%), and instability (9.8%). The rate of septic revision (4,710.5 to 4,426.1 per 100,000 annual TKAs) and aseptic implant loosening (4,502.5 to 3,636.4 per 100,000 annual TKAs) did not change (both P values > 0.05). The rates of instability increased (1,369.2 to 2,609.85 per 100,000 annual TKAs; P = 0.007). The rates of postrevision surgical site infection, periprosthetic joint infection, deep vein thrombosis, and transfusion decreased over the study period, while rates of emergency department visits and readmission increased (all P values <0.05).

CONCLUSIONS

The incidence of revision TKA may be slowing. While the risk of revision for infection and aseptic loosening remains unchanged, revision for instability has increased. The rates of postoperative complications appear to have decreased. Improved surgical technique, implant design, and perioperative protocols may have contributed to these findings. Continued work is necessary to reduce the risk of failure and postoperative complications.

Low incidence of acute kidney injury with combined intravenous and topical antibiotic infusions in periprosthetic joint infection after total knee arthroplasty

Aims

This study aimed to assess the risk of acute kidney injury (AKI) associated with combined intravenous (IV) and topical antibiotic therapy in patients undergoing treatment for periprosthetic joint infections (PJIs) following total knee arthroplasty (TKA), utilizing the Kidney Disease: Improving Global Outcomes (KDIGO) criteria for classification.

Methods

We conducted a retrospective analysis of 162 knees (162 patients) that received treatment for PJI post-TKA with combined IV and topical antibiotic infusions at a single academic hospital from 1 January 2010 to 31 December 2022. The incidence of AKI was evaluated using the KDIGO criteria, focussing on the identification of significant predictors and the temporal pattern of AKI development.

Results

AKI was identified in 9.26% (15/162) of the cohort, predominantly presenting as stage 1 AKI, which was transient in nature and resolved prior to discharge. The analysis highlighted moderate anaemia and lower baseline serum creatinine levels as significant predictors for the development of AKI. Notably, the study found no instances of severe complications such as wound dehiscence, skin erosion, or the need for haemodialysis following treatment.

Conclusion

The findings suggest that the combined use of IV and topical antibiotic therapy in the management of PJIs post-TKA is associated with a low incidence of primarily transient stage 1 AKI. This indicates a potentially favourable renal safety profile, advocating for further research to confirm these outcomes and potentially influence treatment protocols in PJI management.

Antimicrobial Regimens in Cement Spacers for Periprosthetic Joint Infections: A Critical Review

Antibiotic-loaded cement spacers (ALCSs) are essential for treating periprosthetic joint infections (PJIs) by providing mechanical support and local antibiotic delivery. The purpose of this review is to comprehensively examine the various types of spacers utilised in the management of periprosthetic joint infections (PJIs), including both static and articulating variants and to analyse the fundamental principles underlying spacer use, their clinical benefits, the selection and administration of antimicrobial agents, appropriate dosages, and potential adverse effects. Articulating spacers, which allow joint mobility, often yield better outcomes than static ones. Spacer pharmacokinetics are vital for maintaining therapeutic antibiotic levels, influenced by cement porosity, mixing techniques, and the contact area. Antibiotic choice depends on heat stability, solubility, and impact on cement's mechanical properties. Mechanical properties are crucial, as spacers must withstand physical stresses, with antibiotics potentially affecting these properties. Complications, such as tissue damage and systemic toxicity, are discussed, along with mitigation strategies. Future advancements include surface modifications and novel carriers to enhance biofilm management and infection control.

High Incidence of Acute Kidney Injury Following Antibiotic-Loaded Spacer Insertion for Periprosthetic Joint Infection: An Updated Review of the Literature

BACKGROUND

The use of antibiotic-impregnated cement during 2-stage revision arthroplasty for periprosthetic joint infection poses a risk of renal complications following spacer insertion. This systematic review aimed to investigate the rate of acute kidney injury (AKI) following antibiotic-loaded spacer insertion and to identify risk factors associated with this complication.

METHODS

A systematic review was performed using PubMed, Cochrane Central, and Scopus databases. All clinical studies that documented renal complications following antibiotic-loaded spacer insertion for periprosthetic knee (total knee arthroplasty [TKA]) or hip (total hip arthroplasty [THA]) infection were included. Articles that combined THA and TKA outcomes were also included and labeled "THA + TKA." Descriptive statistics were analyzed when data were available.

RESULTS

There were 24 studies (9 THA, 7 TKA, 8 THA + TKA) included. The mean incidences of spacer-related AKI across THA, TKA, and THA + TKA cohorts were 4.2 (range, 0 to 10%), 14 (range, 0 to 19%), and 27% (range, 0 to 35%), respectively. The most common patient-related risk factors for AKI were underlying chronic kidney disease or high baseline creatinine, low preoperative hemoglobin, and blood transfusion requirement. Spacer-related risk factors included high antibiotic dosage (>3.6 g/cement batch) and antibiotic type. While most recovered without complication, select patients required hemodialysis for acute management (2 THA, 18 THA + TKA) and/or developed chronic kidney disease (8 TKA, 8 THA).

CONCLUSION

The rate of AKI following spacer insertion was high and likely under-reported in the literature. Surgeons should be cognizant of this devastating complication and should closely monitor at-risk patients for AKI following antibiotic-loaded spacer insertion.

Systemic Absorption Resulting from Tobramycin-Loaded Antibiotic Cement Spacers Used in the Treatment of Prosthetic Joint Infection

Purpose

Antimicrobial cement spacer (ACS) placement has been a cornerstone of two-stage management of prosthetic hip and knee infection. Pharmacokinetic modelling has described peak systemic antibiotic concentrations within the first 24-48 h post-operatively, followed by rapid clearance. A few studies have, however, identified detectable tobramycin levels in patients with a post-operative decline in creatinine clearance. Our study sought to determine how frequently detectable serum tobramycin levels occurred within the first 72 h following ACS placement in all patients regardless of baseline or subsequent changes in renal function, whether these levels correlated with tobramycin spacer dosage, creatinine clearance, or potential nephrotoxicity risk factors, and whether any patients developed acute kidney injury within the 14-day post-operative period.

Methods

We prospectively enrolled patients with prosthetic hip or knee infections and subsequent ACS placement from October 2017 to February 2020. Patient comorbidities (chronic kidney disease, diabetes mellitus, chronic liver disease, chronic obstructive pulmonary disease, and atrial fibrillation), Charleston Comorbidity Index score, risk factors for post-operative nephrotoxicity (perioperative hypotension and nephrotoxic agent receipt), total tobramycin dosage, post-operative days 1 and 3 serum tobramycin concentrations, and serum creatinine and creatinine clearance throughout a 14-day post-operative period were recorded.

Results

A total of 20 patients were enrolled, comprising 20 spacers with a median total tobramycin dosage of 4.80 g with an interquartile range (IQR) of 4.13-7.20 g. Thirteen patients had a median detectable post-operative day 1 serum tobramycin concentration of 0.80 (IQR 0.50-1.60) mcg/mL. Five of these 13 patients had a median detectable post-operative day 3 serum tobramycin concentration of 0.80 (IQR 0.50-1.10) mcg/mL. A correlation was not found between serum tobramycin drug levels and patient comorbidities, receipt of nephrotoxic medications, or baseline and subsequent post-operative creatinine clearance up to day 14.

Conclusion

The majority of patients who underwent tobramycin ACS placement had detectable serum tobramycin levels in the immediate post-operative period, but most reached undetectable levels within 72 h. There were no reliable perioperative predictors of detectable drug levels.

Incidence, associated factors, and outcomes of acute kidney injury following placement of antibiotic bone cement spacers in two-stage exchange for periprosthetic joint infection: a comprehensive study

BACKGROUND

Two-stage exchange with placement of antibiotic cement spacer (ACS) is the gold standard for the treatment of chronic periprosthetic joint infection (PJI), but it could cause a high prevalence of acute kidney injury (AKI). However, the results of the current evidence on this topic are too mixed to effectively guide clinical practice.

METHODS

We retrospectively identified 340 chronic PJI patients who underwent the first-stage exchange with placement of ACS. The Kidney Disease Improving Global Outcomes guideline was used to define postoperative AKI. Multivariate logistic analysis was performed to determine the potential factors associated with AKI. Furthermore, a systematic review and meta-analysis on this topic were conducted to summarize the knowledge in the current literature further.

RESULTS

In our cohort, the incidence of AKI following first-stage exchange was 12.1%. Older age (per 10 years, OR= 1.509) and preoperative hypoalbuminemia (OR= 3.593) were independent predictors for postoperative AKI. Eight AKI patients progressed to chronic kidney disease after 90 days. A meta-analysis including a total of 2525 PJI patients showed the incidence of AKI was 16.6%, and AKI requiring acute dialysis was 1.4%. Besides, host characteristics, poor baseline liver function, factors contributing to acute renal blood flow injury, and the use of nephrotoxic drugs may be associated with the development of AKI. However, only a few studies supported an association between antibiotic dose and AKI.

CONCLUSION

AKI occurs in approximately one out of every six PJI patients undergoing first-stage exchange. The pathogenesis of AKI is multifactorial, with hypoalbuminemia could be an overlooked associated factor. Although the need for acute dialysis is uncommon, the fact that some AKI patients will develop CKD still needs to be taken into consideration.

Acute kidney injury in the context of staged revision arthroplasty and the use of antibiotic-laden cement spacers: a systematic review

BACKGROUND

The most common cause of revision arthroplasty is prosthetic joint infection (PJI). Chronic PJI is commonly treated with two-stage exchange arthroplasty involving the placement of antibiotic-laden cement spacers (ACS) in the first stage, often containing nephrotoxic antibiotics. These patients often have significant comorbidity burdens and have higher rates of acute kidney injury (AKI). This systematic review aims to assess the current literature to identify (1) AKI incidence, (2) associated risk factors, and (3) antibiotic concentration thresholds in ACS that increase AKI risk following first-stage revision arthroplasty.

METHODS

An electronic search was performed of the PubMed database of all studies involving patients undergoing ACS placement for chronic PJI. Studies assessing AKI rates and risk factors were screened by two authors independently. Data synthesis was performed when possible. Significant heterogeneity prevented meta-analysis.

RESULTS

Eight observational studies consisting of 540 knee PJIs and 943 hip PJIs met inclusion criteria. There were 309 (21%) cases involving AKI. The most commonly reported risk factors included perfusion-related factors (lower preoperative hemoglobin, transfusion requirement, or hypovolemia), older age, increased comorbidity burden, and nonsteroidal anti-inflammatory drug consumption. Only two studies found increased risk with greater ACS antibiotic concentration (> 4 g vancomycin and > 4.8 g tobramycin per spacer in one study, > 3.6 g of vancomycin per batch or > 3.6 g of aminoglycosides per batch in the other); however, these were reported from univariate analyses not accounting for other potential risk factors.

DISCUSSION

Patients undergoing ACS placement for chronic PJI are at an increased risk for AKI. Understanding the risk factors may lead to better multidisciplinary care and safer outcomes for chronic PJI patients.

LEVEL OF EVIDENCE III

Post-operative complications of total knee arthroplasty in patients with hypertension

BACKGROUND

Hypertension is one of the most common comorbidities among patients undergoing surgery. However, few studies have focused on patients undergoing knee arthroplasty, and most of them had small sample sizes. This study aimed to analyze post-operative complications associated with hypertension in patients who underwent knee replacement surgery.

METHODS

Data from the 2019 National Inpatient Sample (NIS) database were used. Patients who underwent primary total knee arthroplasty (pTKA) and those who underwent aseptic revision total knee arthroplasty (rTKA) were analyzed separately. Propensity score matching was performed to reduce the effects of demographic factors and comorbidities other than hypertension on post-operative complications. A multinomial logistic regression that included all significantly different demographics and comorbidities was performed to verify the results and evaluate the odds ratios.

RESULTS

A total of 107,981 patients who underwent pTKA and 6571 who underwent rTKA owing to mechanical complications were identified in the 2019 NIS database. Compared with the non-hypertension group, patients with hypertension had a higher risk of developing acute renal failure and electrolyte disorders after TKA. Further analysis revealed that hyponatraemia and hypokalaemia were associated with hypertension.

CONCLUSIONS

Hypertension was associated with the incidence of acute renal failure after TKA. It is important to identify patients with risk factors for acute renal failure (in addition to hypertension) and take careful measures to prevent acute renal failure in them.

Nephrotoxicity Related to Antibiotic-Loaded Spacers in a 2-Stage Revision for Periprosthetic Joint Infection

Antibiotic-loaded bone cement (ALBC) spacers are the mainstay in 2-stage revision, but antibiotics (vancomycin plus aminoglycosides) may undergo systemic absorption, resulting in acute kidney injury (AKI). Data on spacer antibiotics are heterogeneous. Our objective was to review risk factors for AKI and dosage of antibiotics. Significant AKI risk factors were antibiotic concentration greater than 3 or 3.6 g per cement batch, comorbidities, chronic kidney disease, and hypovolemia. Despite similar spacer antibiotic dosing, there was remarkable variability in serum concentrations. To err on the side of caution, it appears that antibiotic dose below 3 g per cement batch might be relatively safe until more evidence surfaces. Consideration of risk factors for AKI calls for appropriate antibiotic use in 2-stage revision. [Orthopedics. 20XX;XX(X):xx-xx.].

Postoperative Acute Kidney Injury With Dual NSAID Use After Outpatient Primary Total Joint Arthroplasty

BACKGROUND

NSAIDs have been shown to be highly effective analgesic agents in the postoperative period. NSAIDs do have several potential adverse effects, including kidney injury (AKI). Little is known about AKI in the outpatient total joint arthroplasty (TJA) setting, where patient labs are not closely monitored. The objective of this study was to evaluate the renal safety of combined use of ibuprofen for pain control and aspirin for deep vein thrombosis chemoprophylaxis after outpatient primary TJA.

METHODS

Patients undergoing primary total hip or total knee arthroplasty between January 2020 and July 2020 at a single center were included for analysis. All included patients were discharged on a standard regimen including aspirin 81 mg twice a day and ibuprofen 600 mg three times a day. Patients were ordered a serum creatinine test at 2 and 4 weeks postoperatively. Patients with postoperative acute kidney injury were identified per Acute Kidney Injury Network criteria.

RESULTS

Between January 23, 2020, and August 30, 2020, 113 patients were included in this study, of whom creatinine levels were measured in 103 patients (90.3%) at the 2-week postoperative time point, 58 patients (50.9%) at the 4-week time point, and 48 (42.1%) at combined 2- and 4-week time points. Three patients (2.9%) were found to have an AKI.

CONCLUSION

This study found a rate of AKI of 2.9% with the use of dual NSAID therapy postoperatively after primary TJA. All cases occurred at 2 weeks postoperatively and saw spontaneous resolution.

High-Dose Antibiotic Cement Spacers Independently Increase the Risk of Acute Kidney Injury in Revision for Periprosthetic Joint Infection: A Prospective Randomized Controlled Clinical Trial

BACKGROUND

Standard treatment for periprosthetic joint infection (PJI) involves 2-stage exchange with placement of an antibiotic-impregnated cement spacer (ACS). Conflicting evidence exists on the role of ACS in development of acute kidney injury (AKI) after first-stage surgery. In this randomized clinical trial, we aimed to compare the incidence of AKI between the first-stage of a planned 2-stage exchange vs 1-stage exchange. This study design isolates the effect of the ACS in otherwise identical treatment groups.

METHODS

The primary outcome variable was AKI, defined as a creatinine ≥1.5 times baseline or an increase of ≥0.3 mg/dL. Risk factors for AKI were evaluated using bivariate statistical tests and multivariable logistic regression.

RESULTS

Patients who underwent the first stage of a planned 2-stage exchange were significantly more likely to develop AKI compared with the 1-stage exchange group (15 [22.7%] vs 4 [6.6%], P = .011). On multivariable regression analysis, ACS placement (odds ratio 7.48, 95% confidence limit 1.77-31.56) and chronic kidney disease (odds ratio 3.84, 95% confidence limit 1.22-12.08) were independent risk factors for AKI.

CONCLUSION

Our study provides evidence that high-dose antibiotic cement spacers for treatment of PJI are an independent risk factor for AKI. Therefore, efforts to minimize nephrotoxicity should be employed in revision for PJI when possible.

Supratherapeutic Antibiotic Levels and Acute Kidney Injury from Absorption of Topical Antibiotics: A Case Report

CASE

A 96-year-old woman with no baseline renal dysfunction presented with a distal femoral shaft fracture after a ground-level fall. Treatment was with a retrograde intramedullary nail and included placement of topical antibiotics. Postoperatively, she developed acute kidney injury and was found to have supratherapeutic antibiotic levels.

CONCLUSION

This case report demonstrates the risk of clinically relevant systemic absorption along with associated downstream end organ damage with the use of topical antibiotics in certain circumstances. We present this case as an illustration of a rare hazard associated with topical antibiotic use.

Tobramycin Blood Levels after Local Antibiotic Treatment of Bone and Soft Tissue Infection

Local antibiotic delivery using different carriers plays an important role in both infection prophylaxis and treatment. Besides dead space management, these carriers have the advantage of providing a high concentration of local antibiotics with a lower risk of systemic toxicity. Few studies have reported on systemic toxicity associated with antibiotic-impregnated carriers. The present study investigates the systemic tobramycin concentration at 24, 48 and 72 h postoperatively after using tobramycin-loaded polymethyl methacrylate (PMMA) and calcium sulfate (CS) as local antibiotic carriers. Additionally, this work assesses the renal function postoperatively for indications of acute kidney injury (AKI). Fifty-two patients were treated in 58 procedures with tobramycin and vancomycin-loaded PMMA, CS, or both. All systemic tobramycin levels were <2 mcg/mL at 72 h, and the resulting rate of AKI was 12% (7/58). In conclusion, local tobramycin antibiotic delivery using PMMA, CS, or both remains a safe and effective modality in the treatment of osteomyelitis as long as the surgeon is aware of its possible nephrotoxic effect.

Timely explantation of tobramycin-impregnated beads and bone cement to avoid haemodialysis in a patient with worsening renal failure

A male patient with right total knee arthroplasty complicated by prosthetic joint infection on intravenous antimicrobials developed an acute kidney injury (AKI) with creatinine up to 7.3 mg/dL ('normal' range (0.5-1.2 mg/dL)) after hardware removal and tobramycin loaded polymethylmethacrylate beads and spacer placement. The AKI was initially attributed to intravenous vancomycin. Despite discontinuing vancomycin, the AKI worsened. A tobramycin level was collected and resulted at 5.5 µg/mL. Due to high suspicion for aminoglycoside-induced renal toxicity and to prevent haemodialysis, the antibiotic cement spacer with tobramycin-impregnated beads was removed. After the removal, tobramycin level rapidly decreased and renal functions improved. AKI is an increasingly recognised complication related to antibiotic-loaded bone cement (ALBC) due to the systemic absorption of antibiotics. With this case we highlight the early recognition of ALBC-induced renal toxicity necessitating explantation of ALBC and beads in order to prevent haemodialysis and emphasise monitoring aminoglycoside levels in the early postoperative period.

Current Concepts on the Application, Pharmacokinetics and Complications of Antibiotic-Loaded Cement Spacers in the Treatment of Prosthetic Joint Infections

Prosthetic joint infection (PJI) is a devastating complication of total joint replacement surgery. It affects about 2% of primary total joint replacements. Treatment aims at infection eradication and restoration of patient's mobility. Two-stage revision arthroplasty with an interim application of an antibiotic-loaded cement spacer (ALCS) is the widely accepted treatment for PJI. Spacers are powerful local carriers of antibiotics at the site of infection, effective against biofilm-protected microbes. On the other hand, spacers permit some mobility of the patient and facilitate final prosthesis implantation. ALCS's are either commercially available or prepared intraoperatively on prefabricated or improvised molds. Antibiotic elution from the spacer depends on the amount of the antibiotic used for cement impregnation, at the expense of mechanical stiffness of the spacer. The antibiotic should not exceed 4g per 40g of bone cement to preserve the mechanical properties of the cement. Spacers are frequently accompanied by local or systemic complications. The spacer may break, dislocate and compress vessels or nerves of the limb. Systemic complications are the result of excess elution of antibiotic and include nephrotoxicity, hepatotoxicity, ototoxicity, allergic reactions or neutropenia. Elderly patients with comorbidities are at risk to present such complications. Microbial resistance is a potential risk of long-lasting spacer retention. Persisting infection may require multiple spacer replacements.

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.

Renal Toxicity Associated With Resection and Spacer Insertion for Chronic Hip PJI

BACKGROUND

Two-stage exchange arthroplasty with high-dose antibiotic-loaded bone cement spacer and intravenous (IV) antibiotics is the most common method of managing infected total hip arthroplasties. However, the contemporary incidence, risk factors, and outcomes of acute kidney injuries (AKIs) in this cohort are unknown.

METHODS

We identified 227 patients treated with 256 antibiotic-loaded bone cement spacers after resection of an infected primary total hip arthroplasty between 2000 and 2017. Mean age was 65 years, mean body mass index was 30 mg/kg², 55% were men, and 16% had pre-existing chronic kidney disease (CKD). Spacers were in situ for a mean of 15 weeks, concomitantly associated with IV or oral antibiotics for a mean of 6 weeks. AKI was defined as a creatinine ≥1.5X baseline or ≥0.3 mg/dL. Mean follow-up was 8 years.

RESULTS

AKI occurred in 13 patients without pre-existing CKD (7%) vs 10 patients with CKD (28%; OR 5; P = .0001). None required acute dialysis. Postoperative fluid depletion (β = 0.31; P = .0001), ICU requirement (β = 0.40; P = .0001), and acute atrial fibrillation (β = 0.43; P = .0001) were independent predictors for AKI in patients without pre-existing CKD. Duration of in situ spacer, mean antibiotic dose in cement, use of amphotericin B, and type of IV antibiotics were not significant risk factors. At last follow-up, 8 AKIs progressed to CKD, with one receiving dialysis 7 years later.

CONCLUSION

AKIs occurred in 7% of patients with normal renal function, with 5-fold greater risk in those with CKD, and 4% did develop CKD. Importantly, causes of acute renal blood flow impairment were independent predictors for AKI.

LEVEL OF EVIDENCE

Level III, comparative study.

Total Femur Antibiotic Spacers: Effective Salvage for Complex Periprosthetic Joint Infections

BACKGROUND

A simultaneous periprosthetic joint infection (PJI) of an ipsilateral hip and knee arthroplasty is a challenging complication of lower extremity reconstructive surgery. We evaluated the use of total femur antibiotic-impregnated polymethylmethacrylate (PMMA) bone cement spacers in the staged treatment of such limb-threatening PJIs.

METHODS

Thirteen patients were treated with a total femur antibiotic spacer. The mean age at the time of spacer placement was 65 years. Nine patients had polymicrobial PJIs. All spacers incorporated vancomycin (3.0 g/40 g PMMA) and gentamicin (3.6 g/40 g PMMA), while 8 also included amphotericin (150 mg/40 g PMMA). Eleven spacers were biarticular. Twelve spacers were implanted through one longitudinal incision, while 8 of 12 reimplantations occurred through 2 smaller, separate hip and knee incisions. Mean follow-up after reimplantation was 3 years.

RESULTS

Twelve (92%) patients underwent reimplantation of a total femur prosthesis at a mean of 26 weeks. One patient died of medical complications 41 days after spacer placement. At latest follow-up, 3 patients had experienced PJI recurrence managed with irrigation and debridement. One required acetabular component revision for instability. All 12 reimplanted patients retained the total femur prosthesis with no amputations. Eleven (91%) were ambulatory, and 7 (58%) remained on suppressive antibiotics.

CONCLUSION

Total femur antibiotic spacers are a viable, but technically demanding, limb-salvage option for complex PJIs involving the ipsilateral hip and knee. In the largest series to date, there were no amputations and 75% of reimplanted patients remained infection-free. Radical debridement, antimicrobial diversity, prolonged spacer retention, and limiting recurrent soft tissue violation are potential tenets of success.

LEVEL OF EVIDENCE

IV.

Acute Kidney Injury When Treating Periprosthetic Joint Infections After Total Knee Arthroplasties with Antibiotic-Loaded Spacers: Incidence, Risks, and Outcomes

BACKGROUND

Two-stage exchange arthroplasty with a high-dose antibiotic-loaded bone cement (ALBC) spacer and intravenous or oral antibiotics is the most common method of managing a periprosthetic joint infection (PJI) after a total knee arthroplasty (TKA). However, little is known about the contemporary incidence, the risk factors, and the outcomes of acute kidney injuries (AKIs) in this cohort.

METHODS

We identified 424 patients who had been treated with 455 ALBC spacers after resection of a PJI following a primary TKA from 2000 to 2017. The mean age at resection was 67 years, the mean body mass index (BMI) was 33 kg/m2, 47% of the patients were women, and 15% had preexisting chronic kidney disease (CKD). The spacers (87% nonarticulating) contained a mean of 8 g of vancomycin and 9 g of an aminoglycoside per construct (in situ for a mean of 11 weeks). Eighty-six spacers also had amphotericin B (mean, 412 mg). All of the patients were concomitantly treated with systemic antibiotics for a mean of 6 weeks. An AKI was defined as a creatinine level of ≥1.5 times the baseline or an increase of ≥0.3 mg/dL within any 48-hour period. The mean follow-up was 6 years (range, 2 to 17 years).

RESULTS

Fifty-four AKIs occurred in 52 (14%) of the 359 patients without preexisting CKD versus 32 AKIs in 29 (45%) of the 65 patients with CKD (odds ratio [OR], 5; p = 0.0001); none required acute dialysis. Overall, when the vancomycin concentration or aminoglycoside concentration was >3.6 g/batch of cement, the risk of AKI increased (OR, 1.9 and 1.8, respectively; p = 0.02 for both). Hypertension (β = 0.17; p = 0.002), perioperative hypovolemia (β = 0.28; p = 0.0001), and acute atrial fibrillation (β = 0.13; p = 0.009) were independent predictors for AKI in patients without preexisting CKD. At the last follow-up, 8 patients who had sustained an AKI had progressed to CKD, 4 of whom received dialysis.

CONCLUSIONS

In our study, the largest series to date that we are aware of regarding this issue, AKI occurred in 14% of patients with normal renal function at baseline, and 2% developed CKD after undergoing a 2-stage exchange arthroplasty for a PJI after TKA. However, the risk of AKI was fivefold greater in those with preexisting CKD. The causes of acute renal blood flow impairment were independent predictors for AKI.

LEVEL OF EVIDENCE

Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Acute Renal Failure After the First Stage of a 2-Stage Exchange for Periprosthetic Joint Infection

BACKGROUND

Two-stage exchange using antibiotic-loaded spacers is a common approach in treating periprosthetic joint infections. Acute kidney injury (AKIN) can be a systemic complication of this procedure. This study investigates the prevalence of AKIN and identifies potential risk factors.

METHODS

This is a single-center retrospective analysis of patients undergoing 2-stage exchange using a spacer in 285 patients treated between 2010 and 2017. Risk factors were evaluated using parametric and nonparametric analyses and a multivariate, binary logistic regression model.

RESULTS

Thirty-three percent of patients (95/285) developed an AKIN postoperatively. Twenty-four percent (23/95) of these patients had an acute on chronic kidney failure with a previously impaired renal function. In multivariate analysis, a higher age (hazard ratio [HR], 1.034; 95% confidence interval [CI], 1-1.068; P = .046) and a higher baseline creatinine level (HR, 1.94; 95% CI, 1.237-3.052; P = .004) were risk factors for AKIN. Treatment with vancomycin in the spacer or systemically was not associated with AKIN while a high vancomycin blood level (HR, 1.91; 95% CI, 0.913-3.992; P = .086) and fungal infections were (HR, 3.482; 95% CI, 0.968-12.521; P = .056). Furthermore, in univariate analysis, a higher median Charlson comorbidity index (4 vs 3, P = .007), a lower preoperative hemoglobin (10.9 vs 11.7 g/dL, P = .008), and a higher number of blood transfusions (1 vs 0, P = .004) were associated with AKIN.

CONCLUSION

AKIN is common in patients undergoing 2-stage exchange. Associated patient factors, particularly in patients with chronic renal dysfunction, should be optimized. The general use of glycopeptide antibiotics was no risk factor for AKIN.

Is There a Role for Spacer Exchange in Two-Stage Exchange Arthroplasty for Periprosthetic Joint Infection?

Periprosthetic joint infection (PJI) continues to be one of the most serious complications after hip and knee arthroplasty. The choice of surgical treatment depends on a multitude of factors like chronicity of infection, host factors, and institutional or surgeon experience. Two-stage exchange remains one of the most commonly used technique for chronic PJI in the United States of America. The intended two-stage revision may involve an additional interim procedure where the initial antibiotic cement spacer is removed and a new spacer is inserted. Mostly, the rationale behind spacer exchange is an additional load of local antibiotics before proceeding to reimplantation. There is no conclusive evidence whether a spacer exchange confers additional benefits, yet it delays reimplantation and exposes already fragile patients to the risks and morbidity of an additional surgery.

Antibiotic Cement Spacers for Infected Total Knee Arthroplasties

Periprosthetic infection remains a frequent complication after total knee arthroplasty. The most common treatment is a two-stage procedure involving removal of all implants and cement, thorough débridement, insertion of some type of antibiotic spacer, and a course of antibiotic therapy of varying lengths. After some interval, and presumed eradication of the infection, new arthroplasty components are implanted in the second procedure. These knee spacers may be static or mobile spacers, with the latter presumably providing improved function for the patient and greater ease of surgical reimplantation. Numerous types of antibiotic cement spacers are available, including premolded cement components, surgical molds for intraoperative spacer fabrication, and the use of new metal and polyethylene knee components; all these are implanted with surgeon-prepared high-dose antibiotic cement. As there are advantages and disadvantages of both static and the various mobile spacers, surgeons should be familiar with several techniques. There is inconclusive data on the superiority of any antibiotic spacer. Both mechanical complications and postoperative renal failure may be associated with high-dose antibiotic cement spacers.

What Determines the Type and Dose of Antibiotic That Is Needed to Be Added to the Cement Spacer in Patients With Infected Total Ankle Arthroplasty (TAA)?

RECOMMENDATION

We recommend tailoring the antibiotic in cement spacers to the infecting organism if it has been identified, as is typically done in total knee and hip arthroplasty. Otherwise, broad-spectrum antibiotics may be utilized. Medical comorbidities should always be considered, especially with regard to renal function and allergy profile. A thermostable antibiotic should be added to cement.

LEVEL OF EVIDENCE

Consensus.

DELEGATE VOTE

Agree: 100%, Disagree: 0%, Abstain: 0% (Unanimous, Strongest Consensus).

Acute Tubular Necrosis Associated With High Serum Vancomycin and Tobramycin Levels After Revision of Total Knee Arthroplasty With Antibiotic-Containing Calcium Sulfate Beads

We present the case of a 59-year-old male who developed acute tubular necrosis with a serum tobramycin level of 15.9 mg/L after instillation of tobramycin and vancomycin calcium sulfate beads for infected total knee arthroplasty. We emphasize standardizing surgical protocols to mitigate nephrotoxicity based on current efficacy and safety data.

Acute Kidney Injury in Patients Undergoing Total Hip Arthroplasty: A Systematic Review and Meta-Analysis

BACKGROUND

The number of total hip arthroplasties (THA) performed across the world is growing rapidly. We performed this meta-analysis to evaluate the incidence of acute kidney injury (AKI) in patients undergoing THA.

METHODS

A literature search was performed using MEDLINE, EMBASE and Cochrane Database from inception until July 2018 to identify studies assessing the incidence of AKI (using standard AKI definitions of RIFLE, AKIN, and KDIGO classifications) in patients undergoing THA. We applied a random-effects model to estimate the incidence of AKI. The protocol for this meta-analysis is registered with PROSPERO (no. CRD42018101928).

RESULTS

Seventeen cohort studies with a total of 24,158 patients undergoing THA were enrolled. Overall, the pooled estimated incidence rates of AKI and severe AKI requiring dialysis following THA were 6.3% (95% CI: 3.8%⁻10.2%) and 0.5% (95% CI: 0.1%⁻2.3%). Subgroup analysis based on the countries by continent was performed and demonstrated the pooled estimated incidence of AKI following THA of 9.2% (95% CI: 5.6%⁻14.8%) in Asia, 8.1% (95% CI: 4.9%⁻13.2%) in Australia, 7.4% (95% CI: 3.2%⁻16.3%) in Europe, and 2.8% (95% CI: 1.2%⁻17.0%) in North America. Meta-regression of all included studies showed significant negative correlation between incidence of AKI following THA and study year (slope = -0.37, p <0.001). There was no publication bias as assessed by the funnel plot and Egger's regression asymmetry test with p = 0.13 for the incidence of AKI in patients undergoing THA.

CONCLUSION

The overall estimated incidence rates of AKI and severe AKI requiring dialysis in patients undergoing THA are 6.3% and 0.5%, respectively. There has been potential improvement in AKI incidence for patients undergoing THA over time.

Acute Kidney Injury Following Failed Total Hip and Knee Arthroplasty

BACKGROUND

Acute kidney injury (AKI) can complicate primary total joint arthroplasty (TJA) of the hip and knee, although the incidence of AKI following revision TJA including prosthetic joint infection (PJI) is poorly defined. We assessed the incidence and risk factors for AKI following revision TJA including surgical treatment of PJI with placement of an antibiotic-loaded cement (ALC) spacer.

METHODS

We retrospectively reviewed 3218 consecutive failed TJAs. Patients with aseptic failure were compared to those with PJI. AKI was determined by RIFLE creatinine criteria. PJIs treated with placement of ALC were compared to PJIs without. Risk factors for AKI were determined by multivariable analysis within the whole group and within those with PJI.

RESULTS

AKI developed in 3.4% of 2147 patients revised for aseptic reasons and in 45% of 281 with PJI, including 29% of 197 receiving an ALC and 82% of 84 patients treated with other procedures. By multivariable analysis, age, surgery for PJI, total number of surgeries, and estimated GFR 60-90 compared to >90 cc/min/1.73 m² were significantly associated with AKI in the whole cohort. Among PJI patients, age, Charlson comorbidity index, and reimplantation surgery were associated with AKI by multivariable analysis. No differences were found between patients with PJI treated with or without ALC. No modifiable factors were found.

CONCLUSION

AKI develops following aseptic revision TJA at a rate similar to primary TJA, but at a significantly higher rate following surgery for PJI with or without placement of ALC.

Acute Renal Failure due to a Tobramycin and Vancomycin Spacer in Revision Two-Staged Knee Arthroplasty

Two-stage revision total knee arthroplasty (TKA) is the standard of care for prosthetic joint infections. The first stage involves removal of the infected prosthesis and placement of an antibiotic impregnated cement spacer; following a period ranging from 4 weeks to 6 months, the spacer is then removed and replaced with a permanent prosthesis. The advantage to this approach is that antibiotic impregnated spacers provide supratherapeutic levels in the joint without toxic accumulation in serum. However, it remains important for physicians and pharmacists to be aware of antibiotic associated complications in knee revisions. We present a case of a two-stage revision total knee arthroplasty in which a cement antibiotic spacer caused acute renal failure and ultimately resulted in persistent chronic kidney disease without hemodialysis at 2 months' follow-up. Our case reports the third highest serum tobramycin (13.7 mcg/ml) and second highest serum creatinine (8.62 mg/dl) for patients experiencing ARF due to an antibiotic spacer in two-stage revision TKA.

Nephrotoxicity After the Treatment of Periprosthetic Joint Infection With Antibiotic-Loaded Cement Spacers

BACKGROUND

Treatment of periprosthetic joint infections commonly involves insertion of an antibiotic-loaded cement spacer (ACS). The risk for acute kidney injury (AKI) related to use of antibiotic spacers has not been well defined. We aimed to identify the incidence of and risk factors for AKI after placement of an ACS.

METHODS

We performed a prospective cohort study of patients with an infected primary total hip or knee arthroplasty treated with ACSs with vancomycin, gentamicin, and tobramycin. Serum creatinine and glomerular filtration rate data were collected at baseline and weekly intervals for 8 weeks. Patients were classified into Risk, Injury, Failure, Loss of kidney function, and End-stage kidney disease (RIFLE) stages to determine incidence of AKI. Risk factors for kidney injury were identified via regression analysis.

RESULTS

A total of 37 patients (20 total knee arthroplasty and 17 total hip arthroplasty) were included. During the 8 weeks after ACS placement, 10 patients (27%) fit RIFLE criteria for kidney injury and 2 patients (5%) fit RIFLE criteria for kidney failure. No baseline patient characteristics were associated with development of AKI.

CONCLUSION

Patients should be monitored closely for development of AKI after placement of ACSs for the treatment of periprosthetic joint infection. Further research into minimizing risk for AKI is warranted.

Systemic Absorption of Antibiotics From Antibiotic-Loaded Cement Spacers for the Treatment of Periprosthetic Joint Infection

BACKGROUND

Two-stage treatment of periprosthetic joint infections involves placement of high-dose antibiotic-loaded cement spacers (ACSs). Reports of ACS-induced nephrotoxicity have raised concern regarding systemic absorption of antibiotics after ACS placement. We sought to characterize the serum concentrations of antibiotics that occur after ACS placement.

METHODS

We performed a prospective study of patients with an infected primary total hip (THA) or knee arthroplasty (TKA) treated with standardized ACSs with vancomycin, gentamicin, and tobramycin. Serum antibiotic levels were collected weekly for 8 weeks.

RESULTS

Twenty-one patients (10 THA, 11 TKA) were included. Mean serum gentamicin levels ranged between 0.275±0.046 and 0.364±0.163 mg/L; mean serum tobramycin levels ranged from 0.313±0.207 to 0.527±0.424 mg/L; and mean serum vancomycin levels ranged from 5.46±6.6 to 15.34±9.6 mg/L. Serum antibiotic levels were detectable throughout the 8-week duration of ACS treatment. Regression analysis found that diabetes (coefficient 6.73, 95% CI 0.92-12.54, P < .05), blood urea nitrogen (coefficient 0.83, 95% CI 0.45-1.22, P < .001), number of cement doses (coefficient 3.71, 95% CI 0.76-6.66, P < .05), and use of systemic vancomycin (coefficient 6.24, 95% CI 2.72-9.75, P < .001) correlated with serum vancomycin levels. Patient age (coefficient -0.01, 95% CI -0.02 to 0, P < .01) and male sex (coefficient 0.20, 95% CI 0-0.41, P < .05) correlated with serum aminoglycoside level.

CONCLUSION

Systemic absorption of antibiotics from high-dose ACS persists for at least 8 weeks. Patients should be monitored closely for complications related to systemic absorption of antibiotics from ACS treatment.

Total Hip Arthroplasty in the Outpatient Setting: What You Need to Know (Part 1)

The method by which surgeons conduct outpatient total hip arthroplasty (THA) procedures has yet to be fully standardized. Careful examination of components involved in the preoperative phase of outpatient hip arthroplasty procedures may lead to improved outcomes. This article will discuss methods for implementing successful outpatient THA protocols. Specifically it reviews information regarding patient selection criteria, preoperative education, and preoperative medical optimization.

How Long Does Antimycobacterial Antibiotic-loaded Bone Cement Have In Vitro Activity for Musculoskeletal Tuberculosis?

BACKGROUND

Antibiotic-loaded bone cement is accepted as an effective treatment modality for musculoskeletal tuberculosis. However, comparative information regarding combinations and concentrations of second-line antimycobacterial drugs, such as streptomycin and amoxicillin and clavulanic acid, are lacking.

QUESTIONS/PURPOSES

(1) In antibiotic-loaded cement, is there effective elution of streptomycin and Augmentin^® (amoxicillin and clavulanic acid) individually and in combination? (2) What is the antibacterial activity duration for streptomycin- and amoxicillin and clavulanic acid -loaded cement?

METHODS

Six different types of bone cement discs were created by mixing 40 g bone cement with 1 or 2 g streptomycin only, 0.6 g or 1.2 g Augmentin^® (amoxicillin and clavulanic acid) only, and a combination of 1 g streptomycin plus 0.6 g amoxicillin and clavulanic acid and 2 g streptomycin plus 1.2 g amoxicillin and clavulanic acid. Five bone discs of each type were incubated in phosphate buffered saline for 30 days with renewal of the phosphate buffered saline every day. The quantity of streptomycin and/or amoxicillin and clavulanic acid in eluates were measured by a liquid chromatography-mass spectrometry system, and the antimycobacterial activity of eluates against Mycobacterium tuberculosis H37Rv, were calculated by comparing the minimal inhibitory concentration of each eluate with that of tested drugs using broth dilution assay on microplate.

RESULTS

Streptomycin was detected in eluates for 30 days (in 1 g and 2 g discs), whereas 1.2 g amoxicillin and clavulanate eluted until Day 7 and 0.6 g amoxicillin and clavulanate until Day 3. All eluates in streptomycin-containing discs (streptomycin only, and in combination with amoxicillin and clavulanic acid) had effective antimycobacterial activity for 30 days, while amoxicillin and clavulanate-only preparations were only active until Day 14. The antimycobacterial activity of eluates of 2 g streptomycin plus 1.2 g amoxicillin and clavulanate were higher than those of discs containing 1 g streptomycin plus 0.6 g amoxicillin and clavulanate until Day 3, without differences (Day 3, 1 g streptomycin plus 0.6 g amoxicillin and clavulanate: 17.5 ± 6.85 ug/mL; 2 g streptomycin plus 1.2 g amoxicillin and clavulanate: 32.5 ± 16.77 ug/mL; p = 0.109). After Day 7, however, values of the two combinations remained no different than that of Day 30 (Day 30, 1 g streptomycin plus 0.6 g amoxicillin and clavulanate: 0.88 ± 0.34 ug/mL; 2 g streptomycin plus 1.2 g amoxicillin and clavulanate: 0.59 ± 0.94 ug/mL; p = 0.107).

CONCLUSIONS

Streptomycin, in the form of antibiotic-loaded bone cement, had effective elution characteristics and antimycobacterial effects during a 30-day period, whereas amoxicillin and clavulanate only had effective elution and antimycobacterial characteristics during the early period of this study. The two drugs did not interfere with each other during the elution test.

CLINICAL RELEVANCE

This research revealed that combinations of streptomycin and amoxicillin and clavulanate mixed with bone cement are effective for 30 days. Further trials to determine various different combinations of drugs are necessary to improve the effectiveness of treatments for musculoskeletal tuberculosis.

Renal failure after placement of an articulating, antibiotic impregnated polymethylmethacrlyate hip spacer

A 58-year-old male presented with native joint septic arthritis of the hip and osteomyelitis. After treatment with an articulating antibiotic spacer, he developed acute renal failure requiring dialysis. He continued to have elevated serum tobramycin levels exclusively from the antibiotic spacer elution as no intravenous tobramycin was used. Subsequent explantation was required to correct his renal failure. Although renal failure after antibiotic impregnated cement placement is rare, the risk of this potential complication should be considered preoperatively and in the postoperative management of these patients.

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

BACKGROUND

Two-stage revision surgery for infected total hip arthroplasty (THA) is commonly advocated, but substantial morbidity and expense are associated with this technique. In certain cases of infected THA, treatment with one-stage revision surgery and intraarticular infusion of antibiotics may offer a reasonable alternative with the distinct advantage of providing a means of delivering the drug in high concentrations.

QUESTIONS/PURPOSES

We describe a protocol for intraarticular delivery of antibiotics to the hip through an indwelling catheter combined with one-stage revision surgery and examine (1) the success as judged by eradication of infection at 1 year when treating chronically infected cemented stems; (2) success in treating late-onset acute infections in well-ingrown cementless stems; and (3) what complications were associated with this approach in a small case series.

METHODS

Between January 2002 and July 2013, 30 patients (30 hips) presented to the senior author for treatment of infected THA. Of those, 21 patients (21 hips) with infected cemented THAs underwent débridement and single-stage revision to cementless total hip implants followed by catheter infusion of intraarticular antibiotics. Nine patients (nine hips) with late-onset acute infections in cementless THA had bone-ingrown implants. These patients were all more than 2 years from their original surgery and had acute symptoms of infection for 4 to 9 days. Seven had their original THA elsewhere, and two were the author's patients. All were symptom-free until the onset of their infection, and none had postoperative wound complications, fever, or prolonged pain suggestive of a more chronic process. They were treated with débridement and head and liner exchange, again followed by catheter infusion of intraarticular antibiotics. During this time period, this represented all infected THAs treated by the senior author, and all were treated with this protocol; no patient underwent two-stage exchange during this time, and no patients were lost to followup. At the time of the surgery, two Hickman catheters were placed in each hip to begin intraarticular delivery of antibiotics in the early postoperative period. Antibiotics were infused daily into the hip for 6 weeks with the tubes used for infusion only. Eleven of the single-stage revisions and four of the hips treated with débridement had methicillin-resistant Staphylococcus aureus. Patients were considered free of infection if they had no clinical signs of infection and had a normal C-reactive protein and erythrocyte sedimentation rate at 1 year. Complications were ascertained by chart review.

RESULTS

Twenty of 21 (95%) infections in patients who had single-stage revision for chronically infected cemented THA were apparently free from infection and remained so at a mean followup of 63 months (range, 25-157 months). One case grew Candida albicans in the operative cultures and remained free of signs of infection after rerevision followed by infusion of fluconazole. The nine cementless THAs treated with débridement and head/liner exchange all remained free of signs of infection at a mean followup of 74 months (range, 62-121 months). Few complications were associated with the technique. Four patients had elevated serum levels of vancomycin without renal function changes and two patients had transient blood urea nitrogen/creatinine elevations with normal vancomycin levels that resolved with dosage adjustments. No patient had evidence of permanent renal damage. None of the patients in this study developed a chronic fistula or had significant drainage from the catheter site.

CONCLUSIONS

Single-stage revision for chronically infected cemented THA and débridement of bone-ingrown cementless THA with late-onset acute infection followed with indwelling catheter antibiotic infusion can result in infection eradication even when resistant organisms are involved. Larger study groups would better assess this technique and prospective comparisons to more traditional one- and two-stage revision techniques for infected THA will likely require multi-institutional approaches.

LEVEL OF EVIDENCE

Level IV, therapeutic study.