What Is the Most Effective Treatment for Periprosthetic Joint Infection After Total Joint Arthroplasty in Patients with Rheumatoid Arthritis?: A Systematic Review.

BACKGROUND: Rheumatoid arthritis (RA) is a risk factor for periprosthetic joint infection (PJI) after total joint arthroplasty (TJA). The purpose of this study was to perform a systematic review comparing the failure rates of debridement, antibiotics, and implant retention (DAIR), one-stage exchange arthroplasty/revision (OSR), and 2-stage exchange arthroplasty/revision (TSR) for RA patients with PJI and identify risk factors in the RA population associated with increased treatment failure rate. METHODS: PubMed, Ovid MEDLINE, and Ovid Embase databases were screened with the terms "rheumatoid arthritis," "total joint arthroplasty," "prosthetic joint infection," and "treatment for PJI" on August 29, 2021. Four hundred ninety-one studies were screened, of which 86 were evaluated. The primary outcome evaluated was failure of surgical treatment for PJI. RESULTS: Ten retrospective cohort studies were included after full-text screening, yielding 401 patients with RA. Additional demographic and PJI management data were obtained for 149 patients. Patients with RA who underwent TSR demonstrated a lower failure rate (26.8%) than both DAIR (60.1%) and OSR (39.2%) (χ2 = 37.463, p < 0.00001). Patients with RA who underwent DAIR had a 2.27 (95% CI, 1.66-3.10) times higher risk of experiencing treatment failure than those who underwent TSR. Among risk factors, there was a significant difference in the C-reactive protein of patients who did vs. did not experience treatment failure (p = 0.02). CONCLUSION: TSR has a higher rate of success in the management of PJI patients with RA compared with DAIR and OSR. The complete removal of the infected prosthesis and delayed reimplantation may lower the treatment failure rate. LEVEL OF EVIDENCE: Level III. See Instructions for Authors for a complete description of levels of evidence.

Are Accuracy Studies for Periprosthetic Joint Infection Diagnosis Inherently Flawed? And What to Do with Schrödinger's Hips? A Prospective Analysis of the Alpha Defensin Lateral-Flow Test in Chronic Painful Hip Arthroplasties.

Purpose: The most recent diagnostic criteria for periprosthetic joint infection (PJI) include the use of the alpha-defensin (AD) lateral-flow (LF) test, but hip and knee arthroplasties were usually combined in previous studies. This prospective study was designed to examine the accuracy of the AD-LF test for diagnosis of PJI in chronic painful total hip arthroplasties (THA). Materials and Methods: Patients with chronic painful hip arthroplasties were prospectively enrolled between March 2018 and May 2020. Exclusion criteria included acute PJI or an insufficient amount of synovial fluid. The modified Musculoskeletal Infection Society (MSIS) criteria were primarily used for PJI diagnosis. Fifty-seven patients were included in the analysis group. Revision surgery was not performed in 38 patients, for different reasons (clinical group); these patients remain "Schrödinger's hips": in such cases PJI cannot be excluded nor confirmed until you "open the box". Results: The result of the AD-LF test was positive in nine patients and negative in 48 patients. Six patients were diagnosed with PJI. AD-LF sensitivity (MSIS criteria) was 83% (95% confidence interval [CI] 36-100%) and specificity was 92% (95% CI 81-98%). The positive and negative predictive value were 56% and 98%, respectively. Conclusion: The AD test is useful in addition to the existing arsenal of diagnostic tools, and can be helpful in the decision-making process. Not all patients with chronical painful THA will undergo revision surgery. Consequently, in order to determine the reliable diagnostic accuracy of this test, future PJI diagnostic studies should include a second arm of "Schrödinger's hips".

The novel endolysin XZ.700 effectively treats MRSA biofilms in two biofilm models without showing toxicity on human bone cells in vitro.

In this in vitro study the effect of XZ.700, a new endolysin, on methicillin resistant Staphylococcus aureus (MRSA) biofilms grown on titanium was evaluated. Biofilms of S. aureus USA300 were grown statically and under flow, and treatment with XZ.700 was compared with povidone-iodine (PVP-I) and gentamicin. To evaluate the cytotoxic effects of XZ.700 and derived biofilm lysates, human osteocyte-like cells were exposed to biofilm supernatants, and metabolism and proliferation were quantified. XZ.700 showed a significant, concentration dependent reduction in biofilm viability, compared with carrier controls. Metabolism and proliferation of human osteocyte-like cells were not affected by XZ.700 or lysates, unlike PVP-I and gentamicin lysates which significantly inhibited proliferation. Using time-lapse microscopy, rapid biofilm killing and removal was observed for XZ.700. In comparison, PVP-I and gentamicin showed slower biofilm killing, with no apparent biofilm removal. In conclusion, XZ.700 reduced MRSA biofilms, especially under flow condition, without toxicity for surrounding bone cells.

Does the Alpha Defensin ELISA Test Perform Better Than the Alpha Defensin Lateral Flow Test for PJI Diagnosis? A Systematic Review and Meta-analysis of Prospective Studies.

BACKGROUND: Periprosthetic joint infection (PJI) following total joint arthroplasty is a serious complication that causes severe morbidity and adds a major financial burden to the healthcare system. Although there is plenty of research on the alpha-defensin (AD) test, a meta-analysis consisting of only prospective studies investigating AD's diagnostic efficacy has not been performed. Additionally, some important subgroups such as THA and TKA have not been separately analyzed, particularly regarding two commonly used versions of the AD test, the laboratory-based (ELISA) and lateral-flow (LF). QUESTIONS/PURPOSES: (1) Does the AD ELISA test perform better in the detection of PJI than the AD LF test, in terms of pooled sensitivity and specificity, when including prospective studies only? (2) Are there differences in sensitivity or specificity when using AD ELISA and AD LF tests for PJI diagnosis of THA or TKA PJI separately? METHODS: Following the Preferred Reporting Items for Systematic reviews and Meta-Analyses guidelines, we included prospective studies describing the use of either AD test in the workup of pain after total joint arthroplasty (primary or revision, but not after resection arthroplasty). Fifteen studies (AD ELISA: 4; AD LF: 11) were included, with 1592 procedures. Subgroup data on THA and TKA could be retrieved for 1163 procedures (ELISA THA: 123; LF THA: 257; ELISA TKA: 228; LF TKA: 555). Studies not describing THA or TKA, those not using Musculoskeletal Infection Society (MSIS) criteria as the standard for determining the presence or absence of PJI, those not clearly reporting data for the AD test for the total cohort, and those describing data published in another study were excluded. Studies were not excluded based on follow-up duration; the MSIS criteria could be used within a few weeks, when test results were available. Quality was assessed using the Quality Assessment of Diagnostic Accuracy Studies-2 criteria. Study quality was generally good. The most frequent sources of bias were related to patient selection (such as unclear inclusion and exclusion criteria) and flow and timing (uncertainty in place and time of aspiration, for example). Heterogeneity was moderate to high; a bivariate random-effects model therefore was used. To answer both research questions, sensitivity and specificity were calculated for AD ELISA and LF test groups and THA and TKA subgroups, and were compared using z-test statistics and meta-regression analysis. RESULTS: No differences were found between the AD ELISA and the AD LF for PJI diagnosis in the pooled cohorts (THA and TKA combined), in terms of sensitivity (90% versus 86%; p = 0.43) and specificity (97% versus 96%; p = 0.39). Differences in sensitivity for PJI diagnosis were found between the THA and TKA groups for the AD ELISA test (70% versus 94%; p = 0.008); pooled AD LF test sensitivity did not differ between THA and TKA (80% versus 87%; p = 0.20). No differences in specificity were found in either subgroup. CONCLUSIONS: Both the AD ELISA and AD LF test can be used in clinical practice because both have high sensitivity and very high specificity for PJI diagnosis. The lower sensitivity found for diagnosis of PJI in THA for the AD ELISA test must be carefully interpreted because the pooled data were heterogenous and only two studies for this group were included. Future research should analyze TKAs and THAs separately to confirm or disprove this finding. LEVEL OF EVIDENCE: Level II diagnostic study.

Results and Patient Reported Outcome Measures (PROMs) after One-Stage Revision for Periprosthetic Joint Infection of the Hip: A Single-centre Retrospective Study.

Background: Little is known about functional outcome and quality of life (QoL) after one-stage revision for periprosthetic joint infection (PJI) of the hip. Methods: a cohort of 30 subjects treated with one-stage revision between 2011 and 2015 was identified, and questionnaires on functional outcome and QoL were distributed. Results: 28 subjects were successfully treated (93%). Most subjects were referred from other hospitals. Coagulase-negative Staphylococcus was found in 50% of the cases, and 40% of all cultured bacteria were multidrug-resistant. 25% had subsequent revision surgery, unrelated to PJI. Functional outcome was good and QoL scores were high, comparable to prosthetic joint revision surgery in general. Conclusion: Although the cohort was small and statistical analysis was not performed, this study showed that excellent results can be obtained with one-stage revision for hip PJI. Functional outcome and QoL was comparable to prosthetic joint revision surgery in general.

Quality of life after staged revision for infected total hip arthroplasty: a systematic review.

INTRODUCTION: The aim of this review was to assess (health-related) quality of life ([HR]Qol) after 1-stage or 2-stage revision for prosthetic joint infection of the hip (PJI). Additionally, we compared (HR)QoL scores with normative population scores to assess whether QoL is reduced after revision for PJI. METHODS: A systematic search was performed in Embase, Cochrane and Pubmed. We included articles that reported (HR)QoL questionnaires after staged revision for hip PJI with a minimum follow-up of 24 months. Methodological quality was assessed using the MINORS score. RESULTS: The search produced 11,195 results. We selected 12 papers describing 2-stage revisions. The mean MINORS score was 9.8. Average WOMAC scores of 185 patients with a mean follow-up of 69.8 months were 73.Average Short Form 36 (SF-36) scores of 159 patients with a mean follow-up of 40.7 months were 40.4 for the physical component score (PCS) and 51.6 for the mental component score (MCS). Average Short Form 12 (SF-12) scores of 154 patients with a mean follow-up of 73.4 months were: a PCS of 35.4 and a MCS of 49.1. The WOMAC, SF-12 (PCS) and SF-36 (PCS) were respectively 12%, 26.7% and 14.8% lower, compared to normative values. DISCUSSIONS: Patients who underwent 2-stage revision for hip PJI had substantially lower (physical component) (HR)QoL scores, but mental scores were comparable to the general population.

Comparison between open and arthroscopic procedures for lateral clavicle resection.

PURPOSE: Arthroscopic lateral clavicle resection (LCR) is increasingly used, compared to an open approach, but literature does not clearly indicate which approach is preferable. The goal of this study was to compare function and pain between patients who underwent lateral clavicle resection using an open approach and patients treated using an arthroscopic approach. METHODS: Patients who underwent LCR between January 2008 and December 2011 were reviewed. After exclusion, 149 shoulders (143 patients) were eligible for analysis: 41 open and 108 arthroscopic. Disabilities of arm, shoulder and hand (DASH) questionnaire and visual analogue scale (VAS) score were used to assess shoulder function and pain. Complications, operative time, length of hospitalization and resection distance were compared. RESULTS: At a mean follow-up of three years, patients in the open group had significantly less pain by VAS (mm) (Mdn 10, IQR 23) compared with arthroscopic patients (Mdn 20, IQR 50) (p = 0.036). Operative time (minutes) was significantly less for the open approach (Mdn 24.0, IQR 12) compared with arthroscopic (Mdn 38.0, IQR 15) (p < 0.001). Resection distance (mm) was larger for the open approach (Mdn 7.1, IQR 7.0) compared with the arthroscopic approach (Mdn 3.2, IQR 3.1) (p = 0.006), but was not associated with outcome. No significant differences were found for DASH score, complication rate or length of hospitalization. CONCLUSIONS: Both arthroscopic and open approaches for LCR provide excellent outcome in patients with acromioclavicular pain. Less residual pain was found for the open approach, which has shorter operating time and is likely more cost effective.

2-stage revision recommended for treatment of fungal hip and knee prosthetic joint infections.

BACKGROUND AND PURPOSE: Fungal prosthetic joint infections are rare and difficult to treat. This systematic review was conducted to determine outcome and to give treatment recommendations. PATIENTS AND METHODS: After an extensive search of the literature, 164 patients treated for fungal hip or knee prosthetic joint infection (PJI) were reviewed. This included 8 patients from our own institutions. RESULTS: Most patients presented with pain (78%) and swelling (65%). In 68% of the patients, 1 or more risk factors for fungal PJI were found. In 51% of the patients, radiographs showed signs of loosening of the arthroplasty. Candida species were cultured from most patients (88%). In 21% of all patients, fungal culture results were first considered to be contamination. There was co-infection with bacteria in 33% of the patients. For outcome analysis, 119 patients had an adequate follow-up of at least 2 years. Staged revision was the treatment performed most often, with the highest success rate (85%). INTERPRETATION: Fungal PJI resembles chronic bacterial PJI. For diagnosis, multiple samples and prolonged culturing are essential. Fungal species should be considered to be pathogens. Co-infection with bacteria should be treated with additional antibacterial agents. We found no evidence that 1-stage revision, debridement, antibiotics, irrigation, and retention (DAIR) or antifungal therapy without surgical treatment adequately controls fungal PJI. Thus, staged revision should be the standard treatment for fungal PJI. After resection of the prosthesis, we recommend systemic antifungal treatment for at least 6 weeks-and until there are no clinical signs of infection and blood infection markers have normalized. Then reimplantation can be performed.

Prosthetic joint-associated infections treated with DAIR (debridement, antibiotics, irrigation, and retention): analysis of risk factors and local antibiotic carriers in 91 patients.

BACKGROUND AND PURPOSE: For prosthetic joint-associated infection (PJI), a regimen of debridement, antibiotics, irrigation, and retention of the prosthesis (DAIR) is generally accepted for acute infections. Various risk factors associated with treatment success have been described. The use of local antibiotic carriers (beads and sponges) is relatively unknown. We retrospectively analyzed risk factors in a cohort of patients from 3 hospitals, treated with DAIR for PJI. PATIENTS AND METHODS: 91 patients treated with DAIR for hip or knee PJI in 3 Dutch centers between 2004 and 2009 were retrospectively evaluated. The mean follow-up was 3 years. Treatment success was defined as absence of infection after 2 years, with retention of the prosthesis and without the use of suppressive antibiotics. RESULTS: 60 patients (66%) were free of infection at follow-up. Factors associated with treatment failure were: a history of rheumatoid arthritis, late infection (> 2 years after arthroplasty), ESR at presentation above 60 mm/h, and infection caused by coagulase-negative Staphylococcus. Symptom duration of less than 1 week was associated with treatment success. The use of gentamicin sponges was statistically significantly higher in the success group, and the use of beads was higher in the failure group in the univariate analysis, but these differences did not reach significance in the logistic regression analysis. Less surgical procedures were performed in the group treated with sponges than in the group treated with beads. INTERPRETATION: In the presence of rheumatoid arthritis, duration of symptoms of more than 1 week, ESR above 60 mm/h, late infection (> 2 years after arthroplasty), and coagulase-negative Staphylococcus PJI, the chances of successful DAIR treatment decrease, and other treatment methods should be considered.

Implantation of resorbable gentamicin sponges in addition to irrigation and debridement in 34 patients with infection complicating total hip arthroplasty.

We evaluated a prosthesis-retaining treatment protocol for prosthetic joint infection in patients presenting at a mean of 116 days (range 10-1216 days) after primary arthroplasty. Our regime involved irrigation and debridement followed by implantation of biodegradable gentamicin loaded sponges which do not require removal after implantation. Of 34 patients with a deep infection after total hip arthroplasty, Twenty-five were treated successfully, with a mean follow-up of 35 months. There were no permanent complications. This success rate is comparable to earlier studies. Early initiation of treatment demonstrated a tendency for better results, and late chronic infections had a worse outcome. Because the sponges are degradable, a number of further surgical procedures were avoided.