Risk factors for failure in early prosthetic joint infection treated with debridement. Influence of etiology and antibiotic treatment

Biofilm antimicrobial susceptibility testing: where are we and where could we be going?

Our knowledge about the fundamental aspects of biofilm biology, including the mechanisms behind the reduced antimicrobial susceptibility of biofilms, has increased drastically over the last decades. However, this knowledge has so far not been translated into major changes in clinical practice. While the biofilm concept is increasingly on the radar of clinical microbiologists, physicians, and healthcare professionals in general, the standardized tools to study biofilms in the clinical microbiology laboratory are still lacking; one area in which this is particularly obvious is that of antimicrobial susceptibility testing (AST). It is generally accepted that the biofilm lifestyle has a tremendous impact on antibiotic susceptibility, yet AST is typically still carried out with planktonic cells. On top of that, the microenvironment at the site of infection is an important driver for microbial physiology and hence susceptibility; but this is poorly reflected in current AST methods. The goal of this review is to provide an overview of the state of the art concerning biofilm AST and highlight the knowledge gaps in this area. Subsequently, potential ways to improve biofilm-based AST will be discussed. Finally, bottlenecks currently preventing the use of biofilm AST in clinical practice, as well as the steps needed to get past these bottlenecks, will be discussed.

[Structured approach for infected prosthesis]

BACKGROUND

Endoprosthesis infections represent a major challenge for doctors and patients. Due to the increase in endoprosthesis implantation because of the increasing life expectancy, an increase in endoprosthesis infections is to be expected. In addition to infection prophylaxis, methods of infection control become highly relevant, especially in the group of geriatric and multimorbid patients. The aim is to reduce the high 1‑year mortality from prosthesis infections through a structured algorithm.

ALGORITHM FOR PROSTHESIS INFECTIONS

Prosthesis infections can basically be divided into early and late infections. According to the criteria of the International Consensus Meeting, a late infection is defined as the occurrence more than 30 days after implantation. With respect to the planned approach, the (p)TNM classification offers an orientation. In the early postoperative interval the clinical appearance is crucial as in this phase neither laboratory parameters nor an analysis of synovial fluid show a high sensitivity. It is fundamental that, apart from patients with sepsis, environment diagnostics should be initiated. If a late infection is suspected, in addition to radiological diagnostics (X-ray, skeletal scintigraphy and if necessary, computed tomography, CT), laboratory (C-reactive protein, CRP, leukocytes, blood sedimentation, and if necessary, interleukin‑6, procalcitonin) and microbiological diagnostics (arthrocentesis with synovial analysis and microbiology) are indicated; however, in addition to the arthrocentesis result, the clinical appearance is crucial in cases where an exclusion cannot be confirmed by laboratory parameters. If an infection is confirmed, the treatment depends on the spectrum of pathogens, the soft tissue situation and the comorbidities, including a multistage procedure with temporary explantation and, if necessary, implantation of an antibiotic-containing spacer is necessary. A prosthesis preservation using the debridement, antibiotics and implant retention (DAIR) regimen is only appropriate in an acute infection situation. Basically, radical surgical debridement should be carried out to reduce the pathogen load and treatment of a possible biofilm formation for both early and late infections. The subsequent antibiotic treatment (short or long interval) should be coordinated with the infectious disease specialists.

CONCLUSION

A structured approach for prosthesis infections oriented to an evidence-based algorithm provides a sufficient possibility of healing. An interdisciplinary approach involving cooperation between orthopedic and infectious disease specialists has proven to be beneficial. Surgical treatment with the aim of reducing the bacterial load by removing the biofilm with subsequent antibiotic treatment is of intrinsic importance.

Pseudomonas aeruginosa prosthetic joint-infection outcomes: Prospective, observational study on 43 patients

Objectives

Analysis the outcomes of Pseudomonas aeruginosa prosthetic joint infection (PJI), and of their clinical and microbiological characteristics, surgical strategies and antibiotic treatments.

Methods

Monocenter cohort study in a Bone-and-Joint-Infection Referral Center (08/2004 to 10/2018) including all consecutive P. aeruginosa PJIs. Data were extracted from the prospective database, including the following events: relapses, new PJIs, related deaths.

Results

Median [IQR]: among the 43 patients included (28 females; 72 [63-80] years old; 27 hip, 15 knee, and 1 shoulder PJIs), 29 (67%) had underlying comorbidities, 12 (28%) had previously been treated for another PJI and 9 (21%) had undergone previous surgeries for their P. aeruginosa PJI. Eleven (26%) PJIs were polymicrobial, 16 (37%) strains were wild type, 8 (19%) ciprofloxacin-resistant. PJIs were classified as late chronic (n = 33), early postoperative (n = 9) or acute hematogenous infection (n = 1). Forty patients underwent surgery: 27 one-stage and 5 two-stage exchanges, 3 debridement and implant retention, and 5 other surgical strategies. Antibiotic treatments were: 29 received 41 [37-43] days of combination therapy (IV anti-pseudomonal β-lactam and 3-5 days of amikacin, then β-lactam and oral ciprofloxacin), followed by oral ciprofloxacin for a total of 12 weeks; 10 received only IV antibiotics for 83 [77-86] days, including 37 [32-46] days of combination therapy; 49 days of ceftazidime alone for 1. During follow-up lasting 33 [24-64.5] months, 2 relapses, 3 new PJIs, and 2 related deaths occurred. Thirty-three (82%) patients and 93% of those managed with one-stage exchange experienced no event.

Conclusion

Outcomes of our cohort's P. aeruginosa PJIs-predominantly monomicrobial, chronic, ciprofloxacin-susceptible, treated with one-stage exchange and prolonged IV antibiotics-were 82% favorable.

Accuracy of a Novel Preoperative Failure Risk Model for Debridement Antibiotics and Implant Retention (DAIR) in Acute Prosthetic Joint Infection

Given the variable success of the debridement, antibiotics and implant retention (DAIR) procedure in patients with acute prosthetic joint infection (PJI), an accurate selection of candidates is critical. In this study, we set about calculating the predictive value of a novel algorithm for predicting outcome following DAIR developed by Shohat et al. Sixty-four patients who underwent debridement for (early and late) acute PJI in a tertiary-level university hospital were selected, and the aforementioned algorithm was retrospectively applied. Patients with model scores of 40−50%, 50−60%, 60−70%, 70−80% and 80−90% displayed success rates of 33.34%, 41.18%, 57.9%, 78.27% and 100%, respectively. The receiver operating characteristic curve showed an area under the curve of 0.69. The calibration intercept value was 0, and the calibration slope value was 1. Failure rates were significantly higher for the following variables: revision surgery (p = 0.012) index surgery for reasons other than osteoarthritis (p = 0.01), and C-reactive protein level >30 mg/L (p = 0.042). This analysis demonstrated that the Shohat algorithm is associated with an optimal calibration value and a moderate predictive value for failure of a DAIR procedure in patients with acute PJI. Its validation is recommended before it can be routinely applied in daily practice.

Delayed Rifampin Administration in the Antibiotic Treatment of Periprosthetic Joint Infections Significantly Reduces the Emergence of Rifampin Resistance

Rifampin is one of the most important biofilm-active antibiotics in the treatment of periprosthetic joint infection (PJI), and antibiotic regimens not involving rifampin were shown to have higher failure rates. Therefore, an emerging rifampin resistance can have a devastating effect on the outcome of PJI. The aim of this study was to compare the incidence of rifampin resistance between two groups of patients with a PJI treated with antibiotic regimens involving either immediate or delayed additional rifampin administration and to evaluate the effect of this resistance on the outcome. In this retrospective analysis of routinely collected data, all patients who presented with an acute/chronic PJI between 2018 and 2020 were recorded in the context of a single-center comparative cohort study. Two groups were formed: Group 1 included 25 patients with a PJI presenting in 2018-2019. These patients received additional rifampin only after pathogen detection in the intraoperative specimens. Group 2 included 37 patients presenting in 2019-2020. These patients were treated directly postoperatively with an empiric antibiotic therapy including rifampin. In all, 62 patients (32 females) with a mean age of 68 years and 322 operations were included. We found a rifampin-resistant organism in 16% of cases. Rifampin resistance increased significantly from 12% in Group 1 to 19% in Group 2 (p < 0.05). The treatment failure rate was 16% in Group 1 and 16.2% in Group 2 (p = 0.83). The most commonly isolated rifampin-resistant pathogen was Staphylococcus epidermidis (86%) (p < 0.05). The present study shows a significant association between the immediate start of rifampin after surgical revision in the treatment of PJI and the emergence of rifampin resistance, however with no significant effect on outcome.

The role of fibrinogen in predicting reinfection after DAIR for periprosthetic joint infections

Background

Fibrinogen (FIB) has been found to be a promising marker in diagnosing periprosthetic joint infection (PJI), however, the value of FIB in predicting reinfection of PJI is unknown. The purpose of this study was to evaluate the value of FIB in predicting reinfection after debridement, antibiotics, and implant retention (DAIR) for PJI.

Methods

We retrospectively analyzed the clinical data of patients who were diagnosed with PJI and underwent DAIR from 2013 to 2019. The levels of the FIB, erythrocyte sedimentation rate (ESR), and C-reactive protein (CRP) were measured before DAIR. After DAIR, patients were followed and reinfections were identified. For both acute and chronic PJI, the predictive value of FIB was evaluated by calculating the sensitivity, specificity, and area under the curve (AUC) of the receiver operating characteristic curve (ROC), and was compared with traditional inflammatory markers including ESR and CRP.

Results

The expression of FIB differed between patients reinfected and those not reinfected in both acute and chronic PJI (p < 0.05). In patients who underwent DAIR for acute PJI, the sensitivity and specificity of FIB were 81.82 and 83.33%, respectively, which were significantly higher than that of CRP (sensitivity, 72.73%; specificity, 50%; p < 0.05), while the specificity was higher than that of ESR (specificity, 41.67%; p < 0.05). In patients who underwent DAIR for chronic PJI, the sensitivity and specificity of FIB were 80.00 and 66.66%, respectively, which were significantly higher than that of CRP (sensitivity, 53.33%; specificity, 66.66%; p < 0.05) and ESR (sensitivity was 66.00%; specificity, 16.66%; p < 0.05). The ROC curves showed that FIB demonstrated the highest AUC among the biomarkers in both acute and chronic PJI.

Conclusion

FIB is a promising indicator in predicting reinfection after DAIR for both acute and chronic PJI, and it seems to perform better than ESR and CRP.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12891-021-04357-8.

Risk Scores and Machine Learning to Identify Patients With Acute Periprosthetic Joints Infections That Will Likely Fail Classical Irrigation and Debridement

The most preferred treatment for acute periprosthetic joint infection (PJI) is surgical debridement, antibiotics and retention of the implant (DAIR). The reported success of DAIR varies greatly and depends on a complex interplay of several host-related factors, duration of symptoms, the microorganism(s) causing the infection, its susceptibility to antibiotics and many others. Thus, there is a great clinical need to predict failure of the “classical” DAIR procedure so that this surgical option is offered to those most likely to succeed, but also to identify those patients who may benefit from more intensified antibiotic treatment regimens or new and innovative treatment strategies. In this review article, the current recommendations for DAIR will be discussed, a summary of independent risk factors for DAIR failure will be provided and the advantages and limitations of the clinical use of preoperative risk scores in early acute (post-surgical) and late acute (hematogenous) PJIs will be presented. In addition, the potential of implementing machine learning (artificial intelligence) in identifying patients who are at highest risk for failure of DAIR will be addressed. The ultimate goal is to maximally tailor and individualize treatment strategies and to avoid treatment generalization.

Rifampin-accompanied antibiotic regimens in the treatment of prosthetic joint infections: a frequentist and Bayesian meta-analysis of current evidence

Prosthetic joint infections cause serious morbidity and mortality among joint arthroplasty patients. Rifampin-accompanied antibiotic regimens are recommended for gram-positive infections. This study aimed to combine current evidence supporting the rifampin supplement to an effective antibiotic in the treatment of prosthetic joint infections. We conducted a random-effects meta-analysis with frequentist and Bayesian approaches. A total of 13 studies, all observational, were included in the final analysis. The predominant bacteria in eight, two, and three studies were Staphylococcus spp., Propionibacterium spp., and Streptococcus spp., respectively. We pooled data from 568 patients in the staphylococcus subset (OR, 1.18; 95% CIs, [0.76; 1.82]; I² = 23%) and data from 80 patients in the propionibacterium subset (REM OR, 1.61; 95% CIs [0.58; 4.47]; I² = 0%). Both were insignificant with little heterogeneity. We pooled data from 483 patients in the streptococcus subset; the pooled estimate in this subset favored the use of rifampin supplemented regimens (1.84; [0.90; 3.76]) with moderate to high unaccounted heterogeneity (I² = 57%). Bayesian random-effects models produced a posterior probability density indicating that future studies will not favor rifampin supplementation in Staphylococcus infections (μ, 0.074; τ, 0.570; 89% HPD, [- 0.48; 0.54]). Bayesian posterior distribution in the Streptococcus subset displayed a tendency toward rifampin supplementation. Studies had a substantial selection bias. Available evidence did not encourage rifampin-accompanied regimens for staphylococcal infections.

Exchange of Modular Components Improves Success of Debridement, Antibiotics, and Implant Retention: An Observational Study of 575 Patients with Infection After Primary Total Hip Arthroplasty

Debridement, antibiotics, and implant retention (DAIR) is a surgical treatment for periprosthetic joint infection (PJI). DAIR is a desirable treatment option from an economic and patient perspective, if successful. The aim of this observational study was to compare the rates of success, defined as no additional reoperations due to PJI, between DAIR with exchange of modular components and DAIR without exchange in patients who had first-time PJI after primary total hip arthroplasty (THA).

METHODS

Patients with PJI at the site of a primary THA who were treated with DAIR in Sweden between January 1, 2009, and December 31, 2016, were identified in the Swedish Hip Arthroplasty Register. Supplementary questionnaires were sent to orthopaedic departments for additional variables of interest related to PJI. The primary end point was another reoperation due to PJI within 2 years after the first-time DAIR. DAIR with exchange was compared with DAIR without exchange using Kaplan-Meier survival analysis and Cox regression analysis.

RESULTS

A total of 575 patients treated with DAIR for a first-time PJI at the site of a primary THA were analyzed; 364 underwent component exchange and 211 did not. The exchange of components was associated with a lower rate of reoperations due to PJI after DAIR (28.0%) compared with non-exchange (44.1%). The Kaplan-Meier implant survival estimate for exchange was 71.4% (95% confidence interval [CI] = 66.9% to 76.3%) compared with 55.5% (95% CI = 49.1% to 62.7%) for non-exchange. With the analysis adjusted for confounders, DAIR with exchange was associated with a significantly decreased risk of another reoperation due to PJI compared with non-exchange (hazard ratio [HR] = 0.51 [95% CI = 0.38 to 0.68]).

CONCLUSIONS

In patients with a first-time PJI at the site of a primary THA, DAIR with exchange of modular components was superior to non-exchange DAIR. Surgeons should strive to exchange components when they perform DAIR, but there is a need to further identify how DAIR best should be practiced and which patients benefit from it.

LEVEL OF EVIDENCE

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

Debridement, antibiotics, and implant retention for periprosthetic knee infections: a pooling analysis of 1266 cases

Background

The debridement, antibiotics, and implant retention (DAIR) procedure is an established therapeutic option for periprosthetic knee infections (PKI). However, the efficacy and the indication for this procedure are still controversial.

Methods

All the relevant literatures were systematically reviewed and analyzed. The present study aimed to assess the success rate of DAIR in the management of PKI, identify the factors associated with prognosis of DAIR, and establish a simple algorithm for predicting a high success rate of DAIR.

Results

Totally, 33 studies with 1266 cases were included. The overall success rate following DAIR in the management of PKI was 57.11%. In the subgroup analyses, the factors of “the time from symptoms to debridement was < 3 weeks” and “the bacterial species other than methicillin-resistant Staphylococcus aureus” significantly improved the success rate of DAIR and thus were defined as the major criteria. The statistically insignificant factors of “the open debridement and liner exchange” and “the comorbidity of rheumatoid arthritis” were set as the minor criteria. The success rate of DAIR for PKI meeting all the major criteria and no less than one minor criterion was 80.98%, which was significantly higher than the overall success rate of DAIR (p < 0.05).

Conclusion

PKI cases meeting two major criteria and no less than one minor criterion may confer a high success rate of DAIR. This simple algorithm may contribute to identifying the appropriate PKI patient for DAIR treatment and predicting the prognosis of DAIR.

The Different Microbial Etiology of Prosthetic Joint Infections according to Route of Acquisition and Time after Prosthesis Implantation, Including the Role of Multidrug-Resistant Organisms

The aim of our study was to characterize the etiology of prosthetic joint infections (PJIs)-including multidrug-resistant organisms (MDRO)-by category of infection. A multicenter study of 2544 patients with PJIs was performed. We analyzed the causative microorganisms according to the Tsukayama's scheme (early postoperative, late chronic, and acute hematogenous infections (EPI, LCI, AHI) and "positive intraoperative cultures" (PIC)). Non-hematogenous PJIs were also evaluated according to time since surgery: <1 month, 2-3 months, 4-12 months, >12 months. AHIs were mostly caused by Staphylococcus aureus (39.2%) and streptococci (30.2%). EPIs were characterized by a preponderance of virulent microorganisms (S. aureus, Gram-negative bacilli (GNB), enterococci), MDROs (24%) and polymicrobial infections (27.4%). Conversely, coagulase-negative staphylococci (CoNS) and Cutibacterium species were predominant in LCIs (54.5% and 6.1%, respectively) and PICs (57.1% and 15.1%). The percentage of MDROs isolated in EPIs was more than three times the percentage isolated in LCIs (7.8%) and more than twice the proportion found in AHI (10.9%). There was a significant decreasing linear trend over the four time intervals post-surgery for virulent microorganisms, MDROs, and polymicrobial infections, and a rising trend for CoNS, streptococci and Cutibacterium spp. The observed differences have important implications for the empirical antimicrobial treatment of PJIs.

Risk Factors and Treatment Options for Failure of a Two-Stage Exchange

PURPOSE OF REVIEW

Although a two-stage exchange revision is reported to have a high success rate, this strategy may fail as a treatment for prosthetic joint infection (PJI). When it does, resection arthroplasty, arthrodesis, amputation, and chronic antibiotic suppression may play a role. The purpose of this review is to determine which are the main risk factors for a two-stage exchange failure and to analyze the indications and results of resection arthroplasty, arthrodesis, amputation, and antibiotic chronic suppression for PJI.

RECENT FINDINGS

Recent literature demonstrates that the main risk factors for a two-stage exchange failure are as follows: hemodialysis, obesity, multiple previous procedures, diabetes mellitus, corticosteroid therapy, hypoalbuminemia, immunosuppression, rheumatological conditions, coagulation disorders, and infection due to multidrug-resistant (MDR) bacteria or fungal species. Regarding microorganisms, besides Staphylococcus aureus, Streptococcus spp., Enterobacteriaceae species such as Klebsiella pneumoniae and Enterobacter sp., Pseudomonas aeruginosa, or Acinetobacter baumannii, and fungus including Candida sp. are also considered risk factors for a two-stage exchange failure. Resection arthroplasty, arthrodesis, and amputation have a limited role. Chronic suppression is an option for high-risk patients or unfeasible reconstruction. In summary, we report the main risk factors for a two-stage exchange failure and alternative procedures when it occurs. Future research on patient-specific risk factors for a two-stage exchange may aid surgical decision-making and optimization of outcomes.

Functional outcomes of infected hip arthroplasty: a comparison of different surgical treatment options

BACKGROUND

Periprosthetic joint infection (PJI) following total hip arthroplasty (THA) can be treated with irrigation and debridement with head and polyethylene exchange (IDHPE) or 2-stage revision (2SR). Few studies have compared patient-reported outcome measures (PROMs) in patients managed with these treatments.

METHODS

A retrospective review identified 137 patients who had an infected primary THA between 1986-2013. Control cohorts were matched according to age and Charlton Comorbidity Index (CCI). Harris Hip Scores (HHS), Short Form 12 (SF12), and Western Ontario and McMaster Universities Arthritis Index (WOMAC) scores were compared between the control and infected cohorts.

RESULTS

68 patients underwent a 2SR and 69 patients underwent an IDHPE. IDHPE had a 59% success rate in eradicating infection. PROMs for the 2SR cohort were significantly worse than the noninfected controls (SF12-PCS [34.0 vs. 38.3, p = 0.03]; HHS [76.6 vs. 91.7, p<0.001]; and WOMAC [67.3 vs. 79.3, p = 0.005]). There were no significant differences between the noninfected cohort and the successful IDHPE. Significant differences were found between failed IDHPE and noninfected controls (SF12-PCS [42.5 vs. 34.0, p = 0.011]; HHS [92.3 vs. 79.6, p = 0.004]). There was only difference in SF12-MCS scores (50.3 vs. 57.3, p = 0.012) between the 2SR and failed IDHPE cohorts.

CONCLUSIONS

Patients treated with a successful IDHPE had similar outcomes to noninfected patients. Patients that failed IDHPE and went onto 2SR had similar outcomes to those that had a 2SR alone. IDHPE demonstrated a 59% success rate with PROMs equivalent to a noninfected cohort and should be considered in the treatment algorithm of infected THA.