Significant Difference in Antimicrobial Resistance of Bacteria in Septic Revision between Total Knee Arthroplasty and Total Hip Arthroplasty

The Microbiology of Knee Prosthetic Joint Infection and its Influence on Persistent Infection

Periprosthetic joint infection (PJI) following total knee arthroplasty (TKA) is a severe complication causing a significant burden. The study aims were to establish the epidemiology of microorganisms in TKA PJI, the rate of persistent infection requiring further surgery, and the risk factors for this. Microbiological specimens between June 2002 and March 2017 at five regional hospital sites were identified with revision TKA procedures in the National Joint Replacement Registry. The time between procedures, type of revision strategy, and any subsequent further revision operations were collected. At minimum 2-year follow-up, 174 revision TKA were identified, with a mean patient age of 69 ± 11 years. A broad range of pathogens were identified. Fifty cases (29%) had persistent infection requiring at least one further operative procedure, 13 cases required 3 or more. Coagulase-negative Staphylococcus species (CNS) was seen most with failed surgery, polymicrobial infections also posing a significant risk factor. The best chance of a successful PJI surgical strategy was < 12 months from primary TKA, with the greatest risk between 3 and 5 years (p < 0.05). Younger age significantly increased the risk of further surgery (p < 0.05). Management varied; 103 (59%) debridement, antibiotic therapy and implant retention, with further surgery in 29%; 45 (17%) single-stage revision, with further surgery in 13%; and 26 (15%) two-stage revision, with further surgery in 12%. This study presents the most common causative pathogens for PJI in TKA, and the high rate of persistent infection after initial revision surgery. Risk factors for persistent infection and further revision surgery were polymicrobial and CNS infections, patients who presented between 3 and 5 years following primary TKA, and younger age. This study therefore raises important risk factors and areas for future research to reduce the burden of multiple operations after PJI.

Infection Rates After Aseptic Revision Total Hip Arthroplasty With Extended Oral Antibiotic Prophylaxis

INTRODUCTION

Few US studies have investigated the efficacy of extended oral antibiotic prophylaxis (EOAP) in the prevention of periprosthetic joint infection (PJI) after aseptic revision total hip arthroplasty (R-THA). This study compared PJI rates in aseptic R-THA performed with EOAP with PJI rates in published studies of aseptic R-THA patients not receiving EOAP.

METHODS

Prospectively documented data on 127 consecutive aseptic R-THAs were retrospectively reviewed. Evidence-based perioperative infection prevention protocols were used, and all patients were discharged on 7-day EOAP. Superficial and deep infections at 30 and 90 days postoperatively and at mean latest follow-up of 27.8 months were statistically compared with all US studies reporting the prevalence of PJI after aseptic R-THA. Complications related to EOAP within 120 days of the index procedure also are reported.

RESULTS

No superficial or deep infections were observed at 30 and 90 days postoperatively when 7-day postdischarge EOAP was used. Superficial and deep infection rates were 1.57% (two patients) and 3.15% (four patients) at mean latest follow-up, respectively. Comparisons with published 30-day PJI rates of 1.37% ( P = 0.423) and 1.85% ( P = 0.257) were not statistically significant. Two of four comparisons with published 90-day PJI rates of 3.43% ( P = 0.027) and 5.74% ( P = 0.001) were statistically different. The deep PJI rate of 3.15% at mean latest follow-up was significantly lower than two of three published rates at equivalent follow-up including 10.10% ( P = 0.009) and 9.12% ( P = 0.041). No antibiotic-related complications were observed within 120 days of the index procedure.

DISCUSSION

Study findings possibly support the use of EOAP after aseptic R-THA to prevent catastrophic PJI with revision implants, indicating that the efficacy of EOAP cannot be definitively ruled-in or ruled-out based on available evidence.

Second-Line Antibiotic Agents in Patient-Reported Penicillin or Cephalosporin Allergy Have No Negative Impact on Antibiotic Resistance After Hip and Knee Arthroplasty

BACKGROUND

The aim of the present study was to compare causative bacteria and their antibiotic resistance profiles in patients developing a periprosthetic joint infection (PJI) based on preoperative prophylactic antibiotic regimens in primary total hip (THA) and primary total and unicompartmental knee arthroplasty (TKA/UKA).

METHODS

We reviewed all cases of PJI occurring after primary THA and primary TKA/UKA, between 2011 and 2020 in a tertiary referral hospital. The standard preoperative prophylactic antibiotic for primary joint arthroplasty was cefuroxime and recommended second-line agent was clindamycin. Patients were divided by the replaced joint and analyzed independently.

RESULTS

In the THA group, culture-positive PJI was detected in 61 of 3,123 (2.0%) cefuroxime-administered cases and 6 of 206 (2.9%) noncefuroxime-administered cases. In the TKA/UKA group, culture positive PJI was identified in 21 of 2,455 (0.9%) cefuroxime-administered cases and in 3 of 211 (1.4%) noncefuroxime administered cases. The most commonly isolated bacteria in both groups were coagulase negative staphylococci (CNS). There were no statistically significant differences of pathogen spectrum depending on the preoperative antibiotic regimen detected. Antibiotic resistance of isolated bacteria was significantly different in 4 of 27 (14.8%) analyzed antibiotics in THA and in 3 of 22 (13.6%) analyzed antibiotics in TKA/UKA. In all cohorts, a high occurrence of oxacillin-resistant CNS (50.0 to 100.0%) and clindamycin-resistant CNS (56.3 to 100.0%) has been observed.

CONCLUSION

The use of the second-line antibiotic did not influence the pathogen spectrum or antibiotic resistance. However, an alarmingly high proportion of CNS strains was resistant to clindamycin.

Incidence of Rifampicin Resistance in Periprosthetic Joint Infection: A Single-Centre Cohort Study on 238 Patients

BACKGROUND

Rifampicin is a pillar in the treatment of periprosthetic joint infection (PJI). However, rifampicin resistance is an increasing threat to PJI treatment. This study explores the incidence of rifampicin-resistant bacteria over time in a Swedish tertiary referral centre and the association of rifampicin resistance with infection-free survival after PJI.

METHODS

The study included 238 staphylococcal PJIs treated between 2001 and 2020 for which susceptibility data for rifampicin were available. Data on causative bacteria, rifampicin resistance, treatment, and outcome were obtained. Kaplan-Meier survival analysis and Cox regression modelling estimated the infection-free cumulative survival and adjusted hazard ratios (HRs) for the risk of treatment failure.

RESULTS

Rifampicin-resistant causative bacteria were identified in 40 cases (17%). The proportion of rifampicin-resistant agents decreased from 24% in 2010-2015 to 12% in 2016-2020. The 2-year infection-free survival rates were 78.6% (95% CI, 66.4-93.1%) for the rifampicin-resistant group and 90.0% (95% CI, 85.8-94.4%) for the rifampicin-sensitive group. Patients with PJI caused by rifampicin-resistant bacteria had an increased risk of treatment failure (adjusted HR, 4.2; 95% CI, 1.7-10.3).

CONCLUSIONS

The incidence of PJI caused by rifampicin-resistant bacteria did not increase over the past 20 years. The risk of treatment failure in PJI caused by rifampicin-resistant bacteria is more than four times that caused by rifampicin-sensitive bacteria, highlighting the importance of limiting the development of rifampicin resistance.

Mass spectrometry-based proteomic profiling of sonicate fluid differentiates Staphylococcus aureus periprosthetic joint infection from non-infectious failure: A pilot study

PURPOSE

This pilot study aimed to use proteomic profiling of sonicate fluid samples to compare host response during Staphylococcus aureus-associated periprosthetic joint infection (PJI) and non-infected arthroplasty failure (NIAF) and identify potential novel biomarkers differentiating the two.

EXPERIMENTAL DESIGN

In this pilot study, eight sonicate fluid samples (four from NIAF and four from S. aureus PJI) were studied. Samples were reduced, alkylated, and trypsinized overnight, followed by analysis using liquid chromatography-tandem mass spectrometry (LC-MS/MS) on a high-resolution Orbitrap Eclipse mass spectrometer. MaxQuant software suite was used for protein identification, filtering, and label-free quantitation.

RESULTS

Principal component analysis of the identified proteins clearly separated S. aureus PJI and NIAF samples. Overall, 810 proteins were identified based on their detection in at least three out of four samples from each group; 35 statistically significant differentially abundant proteins (DAPs) were found (two-sample t-test p-values ≤0.05 and log2 fold-change values ≥2 or ≤-2). Gene ontology pathway analysis found that microbial defense responses, specifically those related to neutrophil activation, to be increased in S. aureus PJI compared to NIAF samples.

CONCLUSION AND CLINICAL RELEVANCE

Proteomic profiling of sonicate fluid using LC-MS/MS differentiated S. aureus PJI and NIAF in this pilot study. Further work is needed using a larger sample size and including non-S. aureus PJI and a diversty of NIAF-types.

International Survey of Practice for Prophylactic Systemic Antibiotic Therapy in Hip and Knee Arthroplasty

(1) Background: Prophylactic systemic antibiotics are acknowledged to be an important part of mitigating prosthetic joint infections. Controversy persists regarding optimal antibiotic regimes. We sought to evaluate current international antibiotics guidelines for total joint arthroplasty (TJA) of the hip and knee. (2) Methods: 42 arthroplasty societies across 6 continents were contacted and their published literature reviewed. (3) Results: 17 societies had guidelines; of which 11 recommended an antibiotic agent or antibiotic class (10—cephalosporin; 1—cloxacillin); 15 recommended antibiotic infusion within an hour of incision and 10 advised for post-operative doses (8—up to 24 h; 1—up to 36 h; 1—up to 48 h). (4) Conclusions: Prophylactic antibiotic guidelines for TJA are often absent or heterogenous in their advice.

The Impact of Patient-Reported Penicillin or Cephalosporin Allergy on the Occurrence of the Periprosthetic Joint Infection in Primary Knee and Hip Arthroplasty

Reducing the risk of periprosthetic joint infections (PJI) requires a multi-pronged strategy including usage of a prophylactic antibiotic. A history of penicillin or cephalosporin allergy often leads to a change in prophylactic antibiotic regimen to avoid serious side effects. The purpose of the present retrospective study was to determine incidence of PJI based on perioperative antibiotic regimen in total hip arthroplasty (THA), total knee arthroplasty (TKA) or unicompartmental knee arthroplasty (UKA). A review of all primary THAs, primary TKAs and primary UKAs, undertaken between 2011 and 2020 in a tertiary referral hospital, was performed. The standard perioperative antibiotic for joint arthroplasty (JA) in the analyzed tertiary hospital is cefuroxime. There were no differences in prophylactic antibiotic regimen over time. In 7.9% (211 of 2666) of knee arthroplasties and in 6.0% (206 of 3419) of total hip arthroplasties, a second-line prophylactic antibiotic was used. There was no statistically significant higher occurrence of PJI between the first-line and second-line prophylactic antibiotic in knee arthroplasties (p = 0.403) as well as in total hip arthroplasties (p = 0.309). No relevant differences in age, American Society of Anesthesiologists (ASA) score and body mass index (BMI) between the groups were observed.

Microbiological Trends and Antibiotic Susceptibility Patterns in Patients with Periprosthetic Joint Infection of the Hip or Knee over 6 Years

We sought to analyze trends of the causative pathogens and their antibiotic susceptibility patterns in patients with periprosthetic joint infections (PJI) of the hip and knee to get better insights and improve treatment. Retrospective evaluation of all consecutive patients with microbiological detection of a causative pathogen at a tertiary endoprothetic referral center between January 2016 and December 2021 in Germany was performed. Overall, 612 different microorganisms could be detected in 493 patients (hip: n = 293; knee: n = 200). Evaluation did not show a change in the relative abundance of pathogens detected, with coagulase-negative staphylococci (n = 275; 44.9%) found frequently, followed by S. aureus (n = 86; 14.1%), Enterococcus species (n = 57; 9.3%), Streptococcus species (n = 48; 7.8%), and Gram-negative bacteria (n = 80; 13.1%). Evaluation of the antibiotic susceptibilities showed increasing rates of oxacillin-resistant coagulase-negative staphylococci (60.4%; 46.8−76.7%) and piperacillin-tazobactam-resistant Gram-negative bacteria (26.5%; 0−57.1%), although statistically not significant. Resistance of Gram-positive bacteria to vancomycin (<1%) and Gram-negative microorganisms to meropenem (1.25%) remained an exception. In summary, coagulase-negative staphylococci, as the most frequent pathogen, displayed a continuously high rate of oxacillin resistance. For the highest antimicrobial coverage in the case of an empiric therapy/unknown pathogen, vancomycin might be chosen. Level of evidence: IV.