Extended Oral Antibiotics Increase Bacterial Resistance in Patients Who Fail 2-Stage Exchange for Periprosthetic Joint Infection

Preventing Orthopedic Infections

The prevention of orthopedic infections is of critical importance to improve patient outcomes and reduce health care costs. Preventative strategies can be employed preoperatively, including mitigation of medical risk factors, methicillin-resistant Staphylococcus aureus decolonization, appropriate skin preparation, and optimizing perioperative antimicrobial prophylaxis; intraoperatively, including utilizing irrigation, topical antibiotics, infection control measures, and timely debridement/optimal surgical techniques; and postoperatively, including consideration of antibiotic duration after primary arthroplasty and reimplantation. This article provides an evidence-based discussion of these strategies while also highlighting areas where ongoing research may be beneficial.

Debridement, Antibiotics, and Implant Retention for Acute Periprosthetic Joint Infection: Results of 126 Primary Hip Arthroplasties at Extended Follow-Up of Seven Years

BACKGROUND

There is renewed interest in debridement, antibiotics, and implant retention (DAIR) for acute periprosthetic joint infections (PJIs). The purpose of this study was to assess the results of single DAIRs for acute PJI after primary hip arthroplasty in a large series with extended follow-up.

METHODS

We identified 126 hips (108 total hip arthroplasties, 18 hemiarthroplasties) with acute PJIs treated with DAIR followed by chronic antibiotic suppression between 2000 and 2021 at a single institution. Acute postoperative PJI was defined as infection within four weeks of primary hip arthroplasty, and acute hematogenous PJI was defined as infection occurring more than four weeks after primary hip arthroplasty with symptoms for less than 21 days. The mean age was 67 years, 44% were women, and the mean body mass index was 34. Kaplan-Meier survivorship analyses were performed. The mean follow-up was seven years.

RESULTS

Survivorship free of reinfection was 80% at one year, 79% at two years, and 77% at five years. There was no difference in survivorship free of reinfection between early postoperative and acute hematogenous PJIs (P = 0.1). McPherson Host Grade C was predictive of reinfection (hazard ratio 5, P = 0.03). Reinfection was caused by the original organism in 33% of hips. The median time to reinfection was 13 days. Survivorship free of any revision was 82% at five years. Indications for revision included recurrent PJI (91%), dislocation (5%), and aseptic failures (5%).

CONCLUSIONS

In this large series of acute PJIs after primary hip arthroplasties treated with a single DAIR, infection-free survival was 77% at five years. Poor host status predicted reinfection. With a rigorous definition of acute PJI, success was markedly improved at extended follow-up compared to many historical series.

Results of 331 Two-Stage Exchanges for PJI Following THA: Low Reinfection and Mechanical Failure Rates at 10 Years

BACKGROUND

The relative advantages and disadvantages of 2-stage versus 1-stage management of infection following total hip arthroplasty (THA) are the current subject of intense debate. To understand the merits of each approach, detailed information on the short and, importantly, longer-term outcomes of each must be known. The purpose of the present study was to assess the long-term results of 2-stage exchange arthroplasty following THA in one of the largest series to date.

METHODS

We identified 331 periprosthetic joint infections (PJIs) that had been treated with a 2-stage exchange arthroplasty between 1993 and 2021 at a single institution. Patients were excluded if they had had prior treatment for infection. The mean age at the time of reimplantation was 66 years, 38% of the patients were female, and the mean body mass index (BMI) was 30 kg/m 2 . The diagnosis of PJI was based on the 2011 Musculoskeletal Infection Society criteria. A competing-risk model accounting for death was utilized. The mean duration of follow-up was 8 years.

RESULTS

The cumulative incidence of reinfection was 7% at 1 year and 11% at 5 and 10 years. Factors predictive of reinfection included BMI ≥30 kg/m 2 (hazard ratio [HR] = 2; p = 0.049) and the need for a spacer exchange (HR = 3.2; p = 0.006). The cumulative incidence of any revision was 13% at 5 and 10 years. The cumulative incidence of aseptic revision was 3% at 1 year, 7% at 5 years, and 8% at 10 years. Dislocation occurred in 33 hips (11% at 10 years); 15 (45%) required revision. Factors predictive of dislocation were female sex (HR = 2; p = 0.047) and BMI <30 kg/m 2 (HR = 3; p = 0.02). The mean Harris hip score (HHS) improved from 54 to 75 at 10 years.

CONCLUSIONS

In this series of 331 two-stage exchange arthroplasties that were performed for the treatment of infection, we found a low rate of aseptic revision (8%) and a low rate of reinfection (11%) at 10 years. These long-term mechanical and infection data must be kept in mind when considering a paradigm shift to 1-stage exchanges.

LEVEL OF EVIDENCE

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

Effect of oral antibiotics after two-stage revision for periprosthetic joint infection on subsequent antibiotic resistance within a national cohort of United States veterans

Background: Prior studies have indicated that administration of prolonged courses of oral antibiotics after Stage 2 reimplantation surgery for periprosthetic joint infection (PJI) results in a lower rate of recurrent PJI. However, there is concern that this antibiotic usage results in an increased risk of antibiotic resistance in any subsequent PJI that does occur. Methods: We retrospectively reviewed patients who underwent Stage 2 reimplantation surgery for PJI within the national Veterans Affairs hospital system of the United States. We compared those who received at least 2 weeks of oral antibiotics after Stage 2 reimplantation to those who did not. The primary outcome was the proportion of organisms resistant to four classes of antibiotics (tetracyclines, fluoroquinolones, oral beta-lactams, and sulfonamides) in recurrent PJI. Secondary outcomes included recurrent PJI and death. Results: Of the 605 patients who underwent Stage 2 reimplantation for PJI, 154 patients received at least 14 d of antibiotics after surgery and 451 patients did not. Bacteria causing recurrent PJI in patients who received prolonged antibiotics were more likely to be resistant to tetracyclines and trimethoprim-sulfamethoxazole but not oral beta-lactams or fluoroquinolones. There was no difference in risk of recurrent PJI or death between the two groups. Conclusions: Prolonged oral antibiotic treatment after Stage 2 reimplantation increases the risk of antibiotic resistance to some antibiotics in subsequent PJI. We recommend further research to identify the best choice of antibiotic and duration after Stage 2 reimplantation, to maximize benefits while minimizing risks.

Rethinking Repeat Two-Stage Knee Exchange Arthroplasty: Outcomes, Risks, and Decision-Making

BACKGROUND

Chronic periprosthetic joint infection (PJI) presents a major challenge in knee arthroplasty, with varying success rates reported for two-stage exchange arthroplasty (EA) and a lack of consensus on managing failures from such procedures. This study evaluated repeat two-stage EA outcomes for knee PJI after initial treatment failure to identify the risk factors for reimplantation unsuitability and reinfection.

METHODS

We analyzed 114 patients who underwent repeat EA for chronic knee PJI between 2010 and 2018. From an initial cohort of 1,351 patients, we excluded 231: 18 for incomplete records or protocol non-compliance and 213 for prior revisions. Among the remaining 1,119 patients, 150 experienced reinfection. After excluding 36 who did not undergo repeat EA, the final cohort comprised 114 patients. Outcomes were evaluated using Delphi-based consensus success criteria as follows: healed wounds, no further infection interventions, and no PJI-related mortality.

RESULTS

In our study, 34.2% of the patients did not proceed with reimplantation due to reinfection or ongoing infection, which was influenced by factors such as high Charlson Comorbidity Index scores, recurrence of a microorganism, and shorter intervals between initial arthroplasty and reinfection. Among the reimplanted patients, 44.0% underwent further revision for rereinfection. Kaplan-Meier analysis of 1,119 initial, 75 repeat, and 24 re-repeat two-stage cases revealed 5-year infection-free survival rates of 93, 72, and 43%, respectively. This study identified significant reinfection risks in patients who have repeated infections by the same microorganisms, persistent PJI, or multiple spacer redo procedures. A 39.5% rereinfection rate, including 12 amputations and a 15.8% mortality rate, was observed in this series.

CONCLUSIONS

This study underscores the effectiveness of first-time two-stage EA for knee PJI and notes the challenges and lower success rates of subsequent attempts. This emphasizes the importance of identifying high-risk patients for tailored treatment plans and setting realistic expectations of outcomes.

LEVEL OF EVIDENCE

III.

Benefits and Adverse Events Associated With Extended Antibiotic Use for One Year Following Periprosthetic Joint Infection in Total Knee Arthroplasty: A Prospective Cohort Analysis

BACKGROUND

Periprosthetic joint infections (PJIs) are common and serious complications following knee and hip arthroplasty. Our previous retrospective study suggested extended antibiotics following debridement, antibiotics, and implant retention (DAIR) decreased failure rates and were not associated with increased adverse events (AEs) as compared to a standard 6 weeks of antibiotic therapy. Further, extended antibiotics beyond one year did not provide additional benefits. These observations were tested in this prospective cohort study.

METHODS

A prospective cohort of patients who underwent DAIR for total knee arthroplasty PJI and received primary antibiotics were compared to patients who received primary antibiotics combined with extended antibiotics for one year. Participants had a minimum of 2-year follow-up after the final dose of antibiotics.

RESULTS

A prospective cohort of 79 patients was followed, where 39 participants (52.7%) received primary antibiotics and 35 participants (47.3%) received both primary and extended antibiotics following DAIR. Multivariable time-to-event analyses revealed that extended antibiotic use was an independent predictor of treatment success. Infection-free survival differed significantly between the two treatment regimens, as the hazard of PJI failure was significantly lower for extended antibiotics as compared to primary antibiotics alone (adjusted hazard ratio [HR] = 0.46 [0.24 to 0.87], P = 0.017). The AE rates did not significantly differ between patients treated with primary antibiotics only versus primary combined with extended antibiotics.

CONCLUSIONS

This prospective cohort study supports our previous observations that extended antibiotics for one year were associated with lower failure rates as compared to primary antibiotics alone. Extended antibiotics after primary antibiotics were not found to be associated with increased AEs as compared to only primary antibiotics.

Not so Fast: Extended Oral Antibiotic Prophylaxis Does Not Reduce 90-Day Infection Rate Following Joint Arthroplasty

BACKGROUND

Periprosthetic joint infection (PJI) is a devastating complication following both total hip (THA) and knee (TKA) arthroplasty. Extended oral antibiotic (EOA) prophylaxis has been reported to reduce PJI following TJA in high-risk patients. The purpose of this study was to determine if EOA reduces PJI in all-comers and high-risk THA and TKA populations.

METHODS

This is a retrospective cohort study, including 4,576 patients undergoing primary THA or TKA at a single institution from 2018 to 2022. Beginning in 2020, EOA prophylaxis was administered for 10 days following THA or TKA at our institution. Patients were separated into 2 cohorts (1,769 EOA, 2,807 no EOA) based on whether they received postoperative EOA. The 90-day and 1-year outcomes, with a focus on PJI, were then compared between groups. A subgroup analysis of high-risk patients was also performed.

RESULTS

There was no difference in 90-day PJI rates between cohorts (EOA 1 versus no EOA 0.8%; P = .6). The difference in the rate of PJI remained insignificant at 1 year (EOA 1 versus no EOA 1%; P = .9). Similarly, our subgroup analysis of high-risk patients demonstrated no difference in postoperative PJI between EOA (n = 254) and no EOA (n = 396) (0.8 versus 2.3%, respectively; P = .2). Reassuringly, we also found no differences in the incidence of Clostridium difficile infection (EOA 0.1 versus no EOA 0.1%; P > .9) or in antibiotic resistance among those who developed PJI within 90 days (EOA 59 versus no EOA 83%; P = .2).

CONCLUSIONS

With the numbers available for analysis, EOA prophylaxis was not associated with PJI risk reduction following primary TJA when universally deployed. Furthermore, among high-risk patients, there was no statistically significant difference. While we did not identify increased antibiotic resistance or Clostridium difficile infection, we cannot recommend wide-spread adoption of EOA prophylaxis, and clarification regarding the role of EOA, even in high-risk patients, is needed.

What Is the Ideal Duration for Surgical Antibiotic Prophylaxis?

Background: Surgical antibiotic prophylaxis practice became common in the 1970s and has since become almost universal. The earliest articles used three doses over 12 hours with the first being administered before the start of the operation. Conclusions: The duration of prophylaxis has varied widely in practice over time, but an increasing body of evidence has supported shorter durations, most recently with recommendations in influential guidelines to avoid administration after the incision is closed.

How are Oral Antibiotics Being Used in Total Joint Arthroplasty? A Review of the Literature

While the role and benefit of perioperative intravenous (IV) antibiotics in patients undergoing total joint arthroplasty (TJA) is well-established, oral antibiotic use in TJA remains a controversial topic with wide variations in practice patterns. With this review, we aimed to better educate the orthopedic surgeon on when and how oral antibiotics may be used most effectively in TJA patients, and to identify gaps in the literature that could be clarified with targeted research. Extended oral antibiotic prophylaxis (EOAP) use in high-risk primary, aseptic revision, and exchange TJA for infection may be useful in decreasing periprosthetic joint infection (PJI) rates. When prescribing oral antibiotics either as EOAP or for draining wounds, patient factors, type of surgery, and type of infectious organisms should be considered in order to optimally prevent and treat PJI. It is important to maintain antibiotic stewardship by administering the proper duration, dose, and type of antibiotics and by consulting infectious disease when necessary.

How We Approach Suppressive Antibiotic Therapy Following Debridement, Antibiotics, and Implant Retention for Prosthetic Joint Infection

The optimal treatment of prosthetic joint infection (PJI) remains uncertain. Patients undergoing debridement, antibiotics, and implant retention (DAIR) receive extended antimicrobial treatment, and some experts leave patients at perceived highest risk of relapse on suppressive antibiotic therapy (SAT). In this narrative review, we synthesize the literature concerning the role of SAT to prevent treatment failure following DAIR, attempting to answer 3 key questions: (1) What factors identify patients at highest risk for treatment failure after DAIR (ie, patients with the greatest potential to benefit from SAT), (2) Does SAT reduce the rate of treatment failure after DAIR, and (3) What are the rates of treatment failure and adverse events necessitating treatment discontinuation in patients receiving SAT? We conclude by proposing risk-benefit stratification criteria to guide use of SAT after DAIR for PJI, informed by the limited available literature.

Periprosthetic Joint Infection: Current Clinical Challenges

Over the last several decades, periprosthetic joint infection has been increasing in incidence and is occurring in more complex patients. While there have been advances in both surgical and medical treatment strategies, there remain important gaps in our understanding. Here, we share our current approaches to the diagnosis and management of periprosthetic joint infection, focusing on frequent clinical challenges and collaborative interdisciplinary care.

The Impact of Antimicrobial Therapy Duration in the Treatment of Prosthetic Joint Infections Depending on Surgical Strategies: A Systematic Review and Meta-analysis

The aim of this systematic review was to address the question if short antibiotic treatment (SAT; at least 4 but <12 weeks) versus long antibiotic treatment (LAT) affects outcomes in prosthetic joint infections (PJIs). Database research (Medline, Embase, Web of Science, Scopus, Cochrane) retrieved 3740 articles, of which 10 studies were included in the analysis. Compared to LAT, 11% lower odds of treatment failure in the SAT group were found, although the difference was not statistically significant (pooled odds ratio, 0.89 [95% confidence interval, .53-1.50]). No difference in treatment failure was found between SAT and LAT once stratified by type of surgery, studies conducted in the United States versus Europe, study design, and follow-up. There is still no conclusive evidence that antibiotic treatment of PJIs for 12 weeks or longer is associated with better outcomes, irrespective of the type of surgical procedure. Most recent, high-quality studies tend to favor longer antibiotic courses, making them preferable in most situations.

The Cost-Effectiveness of Extended Oral Antibiotic Prophylaxis for Infection Prevention After Total Joint Arthroplasty in High-Risk Patients

BACKGROUND

Extended oral antibiotic prophylaxis may decrease rates of prosthetic joint infection (PJI) after total joint arthroplasty (TJA) in patients at high risk for infection. However, the cost-effectiveness of this practice is not clear. In this study, we used a break-even economic model to determine the cost-effectiveness of routine extended oral antibiotic prophylaxis for PJI prevention in high-risk TJA patients.

METHODS

Baseline PJI rates in high-risk patients, the cost of revision arthroplasty for PJI, and the costs of extended oral antibiotic prophylaxis regimens were obtained from the literature and institutional purchasing records. These variables were incorporated in a break-even economic model to calculate the absolute risk reduction (ARR) in infection rate necessary for extended oral antibiotic prophylaxis to be cost-effective. ARR was used to determine the number needed to treat (NNT).

RESULTS

Extended oral antibiotic prophylaxis with Cefadroxil in patients at high risk for PJI was cost-effective at an ARR in baseline infection rate of 0.187% (NNT = 535) and 0.151% (NNT = 662) for TKA and THA, respectively. Cost-effectiveness was preserved with varying costs of antibiotic regimens, PJI treatment costs, and infection rates.

CONCLUSION

The use of extended oral antibiotic prophylaxis may reduce PJI rates in patients at high risk for infection following TJA and appears to be cost-effective. However, the current evidence supporting this practice is limited in quality. The use of extended oral antibiotic prophylaxis should be weighed against the possible development of future antimicrobial resistance, which may change the value proposition.

Molecular Approach for the Laboratory Diagnosis of Periprosthetic Joint Infections

The incidence of total joint arthroplasty is increasing over time since the last decade and expected to be more than 4 million by 2030. As a consequence, the detection of infections associated with surgical interventions is increasing and prosthetic joint infections are representing both a clinically and economically challenging problem. Many pathogens, from bacteria to fungi, elicit the immune system response and produce a polymeric matrix, the biofilm, that serves as their protection. In the last years, the implementation of diagnostic methodologies reduced the error rate and the turn-around time: polymerase chain reaction, targeted or broad-spectrum, and next-generation sequencing have been introduced and they represent a robust approach nowadays that frees laboratories from the unique approach based on culture-based techniques.