Usefulness of teicoplanin for preventing methicillin-resistant Staphylococcus aureus infections in orthopedic surgery

Trial of Vancomycin and Cefazolin as Surgical Prophylaxis in Arthroplasty

BACKGROUND

The addition of vancomycin to beta-lactam prophylaxis in arthroplasty may reduce surgical-site infections; however, the efficacy and safety are unclear.

METHODS

In this multicenter, double-blind, superiority, placebo-controlled trial, we randomly assigned adult patients without known methicillin-resistant Staphylococcus aureus (MRSA) colonization who were undergoing arthroplasty to receive 1.5 g of vancomycin or normal saline placebo, in addition to cefazolin prophylaxis. The primary outcome was surgical-site infection within 90 days after surgery.

RESULTS

A total of 4239 patients underwent randomization. Among 4113 patients in the modified intention-to-treat population (2233 undergoing knee arthroplasty, 1850 undergoing hip arthroplasty, and 30 undergoing shoulder arthroplasty), surgical-site infections occurred in 91 of 2044 patients (4.5%) in the vancomycin group and in 72 of 2069 patients (3.5%) in the placebo group (relative risk, 1.28; 95% confidence interval [CI], 0.94 to 1.73; P = 0.11). Among patients undergoing knee arthroplasty, surgical-site infections occurred in 63 of 1109 patients (5.7%) in the vancomyin group and in 42 of 1124 patients (3.7%) in the placebo group (relative risk, 1.52; 95% CI, 1.04 to 2.23). Among patients undergoing hip arthroplasty, surgical-site infections occurred in 28 of 920 patients (3.0%) in the vancomyin group and in 29 of 930 patients (3.1%) in the placebo group (relative risk, 0.98; 95% CI, 0.59 to 1.63). Adverse events occurred in 35 of 2010 patients (1.7%) in the vancomycin group and in 35 of 2030 patients (1.7%) in the placebo group, including hypersensitivity reactions in 24 of 2010 patients (1.2%) and 11 of 2030 patients (0.5%), respectively (relative risk, 2.20; 95% CI, 1.08 to 4.49), and acute kidney injury in 42 of 2010 patients (2.1%) and 74 of 2030 patients (3.6%), respectively (relative risk, 0.57; 95% CI, 0.39 to 0.83).

CONCLUSIONS

The addition of vancomycin to cefazolin prophylaxis was not superior to placebo for the prevention of surgical-site infections in arthroplasty among patients without known MRSA colonization. (Funded by the Australian National Health and Medical Research Council; Australian New Zealand Clinical Trials Registry number, ACTRN12618000642280.).

Obese patients have higher rates of polymicrobial and Gram-negative early periprosthetic joint infections of the hip than non-obese patients

Background

Obese patients are more likely to develop periprosthetic joint infection (PJI) after primary total joint arthroplasty. This study compared the clinical and microbiological characteristics of non-obese, obese and severely obese patients with early PJI, in order to ultimately optimize antibiotic prophylaxis and other prevention measures for this specific patient category.

Methods

We retrospectively evaluated patients with early PJI of the hip and knee treated with debridement, antibiotics and implant retention (DAIR) between 2006 and 2016 in three Dutch hospitals. Only patients with primary arthroplasties indicated for osteoarthritis were included. Early PJI was defined as an infection that developed within 90 days after index surgery. Obesity was defined as a BMI ≥30kg/m² and severe obesity as a BMI ≥35kg/m².

Results

A total of 237 patients were analyzed, including 64 obese patients (27.0%) and 62 severely obese patients (26.2%). Compared with non-obese patients, obese patients had higher rates of polymicrobial infections (60.3% vs 33.3%, p<0.001) with more often involvement of Enterococcus species (27.0% vs 11.7%, p = 0.003). Moreover, severely obese patients had more Gram-negative infections, especially with Proteus species (12.9% vs 2.3%, p = 0.001). These results were only found in periprosthetic hip infections, comprising Gram-negative PJIs in 34.2% of severely obese patients compared with 24.7% in obese patients and 12.7% in non-obese patients (p = 0.018).

Conclusions

Our results demonstrate that obese patients with early periprosthetic hip infections have higher rates of polymicrobial infections with enterococci and Gram-negative rods, which stresses the importance of improving preventive strategies in this specific patient category, by adjusting antibiotic prophylaxis regimens, improving disinfection strategies and optimizing postoperative wound care.

Incidence and risk of surgical site infection after adult femoral neck fractures treated by surgery: A retrospective case-control study

Surgical site infections (SSI) are devastating complications after surgery for femoral neck fractures. There are a lot of literature have shown a strong association between diabetic patients and SSI. This study aimed to identify diabetes as an independent risk factor of SSI, focusing on femoral neck fractures, and to investigate the other potential risk factors for SSI.We retrospectively collected data from patients who underwent surgery for femoral neck fractures through the medical record management system at a single level 1 hospital between January 2015 and June 2016. Demographic and clinical patient factors and characteristics of SSI were recorded. The case group was defined as patients with SSI and the control group was defined as patients without SSI. Univariate and multivariate analyses were performed to determine the risk factors for SSI.Data were provided for 692 patients, among whom 26 had SSI, representing an incidence rate of 3.67%. In the SSI group, 24 (3.47%) patients had superficial infection and 2 (0.29%) had deep infection. On multivariate analysis, diabetes (P < .001) was determined an independent risk factor of SSI, so were surgery performed between May and September (P = .04), body mass index (P = .031), corticosteroid therapy (P = .003), anemia (P = .041), and low preoperative hemoglobin levels.Our results suggest that clinicians should recognize patients with these factors, particularly diabetes. And taking management optimally in the preoperative period will prevent the SSI after femoral neck fracture.

Prosthetic joint infection-a devastating complication of hemiarthroplasty for hip fracture

Background and purpose - Hemiarthroplasty is the most common treatment in elderly patients with displaced femoral neck fracture. Prosthetic joint infection (PJI) is a feared complication. The infection rate varies in the literature, and there are limited descriptive data available. We investigated the characteristics and outcome of PJI following hemiarthroplasty over a 15-year period. Patients and methods - Patients with PJI were identified among 519 patients treated with hemiarthroplasty for a femoral neck fracture at Oslo University Hospital between 1998 and 2012. We used prospectively registered data from previous studies, and recorded additional data from the patients' charts when needed. Results - Of the 519 patients, we identified 37 patients (6%) with early PJI. 20 of these 37 patients became free of infection. Soft tissue debridement and retention of implant was performed in 35 patients, 15 of whom became free of infection with an intact arthroplasty. The 1-year mortality rate was 15/37. We found an association between 1-year mortality and treatment failure (p = 0.001). Staphylococcus aureus and polymicrobial infection were the most common microbiological findings, each accounting for 14 of the 37 infections. Enterococcus spp. was found in 9 infections, 8 of which were polymicrobial. There was an association between polymicrobial infection and treatment failure, and between polymicrobial infection and 1-year mortality. Interpretation - PJI following hemiarthroplasty due to femoral neck fracture is a devastating complication in the elderly. We found a high rate of polymicrobial PJIs frequently including Enterococcus spp, which is different from what is common in PJI after elective total hip arthroplasty.

Surgical Site Infection After Surgery to Repair Femoral Neck Fracture: A French Multicenter Retrospective Study

Objective.

Femoral neck fracture is the most frequent orthopedic emergency among elderly persons. Despite a high prevalence of methicillin-resistant Staphylococcus aureus (MRSA) carriage in this population, no multicenter study of antibiotic prophylaxis practices and the rate and microbiological characteristics of surgical site infection (SSI) has been performed in France.

Design.

Retrospective, multicenter cohort study.

Setting.

Twenty-two university and community hospitals in France.

Patients.

Each center provided data on 25 consecutive patients who underwent surgery for femoral neck fracture during the first quarter of 2005. Demographic, clinical, and follow-up characteristics were recorded, and most patients had a follow-up office visit or were involved in a telephone survey 1 year after surgery.

Results.

These 22 centers provided data on 541 patients, 396 (73%) of whom were followed up 1 year after surgery. Of 504 (93%) patients for whom antibiotic prophylaxis was recorded, 433 (86%) received a cephalosporin. Twenty-two patients had an SSI, for a rate of 5.6% (95% confidence interval, 3.7-8.0). SSI was reported for 15 (6.9%) of patients who had a prosthesis placed and for 7 (3.9%) who underwent osteosynthesis (P = .27). SSI was diagnosed a median of 30 days after surgery (interquartile range, 21-41 days); 7 (32%) of these SSIs were superficial infections, and 15 (68%) were deep or organ-space infections. MRSA caused 7 SSIs (32%), Pseudomonas aeruginosa caused 5 (23%), other staphylococci caused 4 (18%), and other bacteria caused 2 (9%); the etiologic pathogen was unknown in 4 cases (18%). Reoperation was performed for 14 patients with deep or organ-space SSI, including 6 of 7 patients with MRSA SSI. The mortality rate 1 year after surgery was 20% overall but 50% among patients with SSI. In univariate analysis, only the National Nosocomial Infections Surveillance System risk index score was significantly associated with SSI (P = .006).

Conclusions.

SSI after surgery for femoral neck fracture is severe, and MRSA is the most frequently encountered etiologic pathogen. A large, multicenter prospective trial is necessary to determine whether the use of antibiotic prophylaxis effective against MRSA would decrease the SSI rate in this population.

Prophylaxis with teicoplanin and cefuroxime reduces the rate of prosthetic joint infection after primary arthroplasty

The aim of this study was to compare the prosthetic joint infection (PJI) rate after total joint arthroplasty in two consecutive periods of treatment with different antibiotic prophylaxes: cefuroxime versus cefuroxime plus teicoplanin. We retrospectively reviewed 1,896 patients who underwent total hip arthroplasty or total knee arthroplasty between March 2010 and February 2013. From March 2010 to August 2011, patients received 1.5 g of cefuroxime during induction of anesthesia and another 1.5 g 2 h later (the C group). From September 2011, 800 mg of teicoplanin was added to cefuroxime (the CT group). Throughout the period studied, there were no variations in pre- or postoperative protocols. Univariate and multivariate analyses were performed to evaluate independent predictors of PJI. There were 995 (55.7%) patients in the C group and 791 (44.3%) in the CT group. Patients in the CT group had a significantly lower PJI rate than patients in the C group (1.26% versus 3.51%, P=0.002). There were no infections due to Staphylococcus aureus in the CT group (0% versus 1.6% in the C group, P<0.001). A stepwise forward Cox regression model identified male sex (hazard ratio [HR], 3.85; 95% confidence interval [CI], 2.09 to 7.18), a body mass index of ≥35 kg/m2 (HR, 2.93; 95% CI, 1.37 to 6.27), the presence of lung disease (HR, 2.46; 95% CI, 1.17 to 5.15), and red blood cell transfusion (HR, 3.70; 95% CI, 1.89 to 7.23) to be independent variables associated with a higher risk of PJI. The addition of teicoplanin was associated with a lower risk of infection (HR, 0.35; 95% CI, 0.17 to 0.74). In conclusion, the addition of teicoplanin to cefuroxime during primary arthroplasty was associated with a significant reduction in the global PJI rate due to a reduction of infections caused by Gram-positive bacteria.

Special issues involving periprosthetic infection in immunodeficiency patients

Chronic systemic illnesses such as diabetes mellitus, chronic kidney disease (CKD), liver cirrhosis, neoplasia, etc. have been clearly associated with high rates of SWI. However, the exact mechanisms underlying these observations are still under investigation.

Chronic kidney disease (CKD) is a growing problem in our society. Many of these patients will require an arthroplasty and it appears that the prosthetic infection risk for these types of patients is much higher than in the normal population. The risk of complications due to infection seems to be lower in patients with kidney transplants than in patients undergoing haemodialysis. Both prophylaxis and treatment of infection in patients with CKD should be carried out with a strict monitoring of potentially nephrotoxic antibiotics.

The literature on the prognosis and risk of infection in patients with haematopoietic stem cell transplant is scarce and occasionally contradictory. The optimal time for the surgery should be determined by taking into account the immunological state of the patient and should be avoided, as much as possible, during the first year after the HSCT.

Child’s classification system is the most widely used method of stratifying the surgical risk for patients with cirrhosis; the infection appeared to be associated in a statistically significant way with advanced age and a Child B pre-operative classification.

The prevention of prosthetic joint infections in HIV-infected patients should not be significantly different from the prevention for any other patient. Those patients that receive adequate antiretroviral treatment and periodic laboratory control show infection rates and periprosthetic complications that are similar to those for patients not affected by HIV. Therefore, the patient’s level of immunodeficiency is the most important prognostic factor for prosthetic infection.

The particular immunological condition of these patients can lead to infections due to particular microorganisms that immunocompetent patients do not have to deal with. Of all possibilities, because of their frequency and difficulty to treat, infections caused by methicillin-resistant S. aureus and fungus are highlighted.

Effectiveness of a bundled intervention of decolonization and prophylaxis to decrease Gram positive surgical site infections after cardiac or orthopedic surgery: systematic review and meta-analysis

OBJECTIVE

To evaluate studies assessing the effectiveness of a bundle of nasal decolonization and glycopeptide prophylaxis for preventing surgical site infections caused by Gram positive bacteria among patients undergoing cardiac operations or total joint replacement procedures.

DESIGN

Systematic review and meta-analysis.

DATA SOURCES

PubMed (1995 to 2011), the Cochrane database of systematic reviews, CINAHL, Embase, and clinicaltrials.gov were searched to identify relevant studies. Pertinent journals and conference abstracts were hand searched. Study authors were contacted if more data were needed.

ELIGIBILITY CRITERIA

Randomized controlled trials, quasi-experimental studies, and cohort studies that assessed nasal decolonization or glycopeptide prophylaxis, or both, for preventing Gram positive surgical site infections compared with standard care.

PARTICIPANTS

Patients undergoing cardiac operations or total joint replacement procedures. DATA EXTRACTION AND STUDY APPRAISAL: Two authors independently extracted data from each paper and a random effects model was used to obtain summary estimates. Risk of bias was assessed using the Downs and Black or the Cochrane scales. Heterogeneity was assessed using the Cochran Q and I(2) statistics.

RESULTS

39 studies were included. Pooled effects of 17 studies showed that nasal decolonization had a significantly protective effect against surgical site infections associated with Staphylococcus aureus (pooled relative risk 0.39, 95% confidence interval 0.31 to 0.50) when all patients underwent decolonization (0.40, 0.29 to 0.55) and when only S aureus carriers underwent decolonization (0.36, 0.22 to 0.57). Pooled effects of 15 prophylaxis studies showed that glycopeptide prophylaxis was significantly protective against surgical site infections related to methicillin (meticillin) resistant S aureus (MRSA) compared with prophylaxis using β lactam antibiotics (0.40, 0.20 to 0.80), and a non-significant risk factor for methicillin susceptible S aureus infections (1.47, 0.91 to 2.38). Seven studies assessed a bundle including decolonization and glycopeptide prophylaxis for only patients colonized with MRSA and found a significantly protective effect against surgical site infections with Gram positive bacteria (0.41, 0.30 to 0.56).

CONCLUSIONS

Surgical programs that implement a bundled intervention including both nasal decolonization and glycopeptide prophylaxis for MRSA carriers may decrease rates of surgical site infections caused by S aureus or other Gram positive bacteria.

Targeting agr- and agr-Like quorum sensing systems for development of common therapeutics to treat multiple gram-positive bacterial infections

Invasive infection by the Gram-positive pathogen Staphylococcus aureus is controlled by a four gene operon, agr that encodes a quorum sensing system for the regulation of virulence. While agr has been well studied in S. aureus, the contribution of agr homologues and analogues in other Gram-positive pathogens is just beginning to be understood. Intriguingly, other significant human pathogens, including Clostridium perfringens, Listeria monocytogenes, and Enterococcus faecalis contain agr or analogues linked to virulence. Moreover, other significant human Gram-positive pathogens use peptide based quorum sensing systems to establish or maintain infection. The potential for commonality in aspects of these signaling systems across different species raises the prospect of identifying therapeutics that could target multiple pathogens. Here, we review the status of research into these agr homologues, analogues, and other peptide based quorum sensing systems in Gram-positive pathogens as well as the potential for identifying common pathways and signaling mechanisms for therapeutic discovery.

The role of prophylactic antibiotics in open fractures in an era of community-acquired methicillin-resistant Staphylococcus aureus

Infection is a feared complication and a common cause of loss of function following open fractures. Despite the evidence supporting the administration of prophylactic antibiotics after open fractures, data demonstrating the optimal regimen is lacking. We reviewed the data supporting the current prophylaxis recommendations and the changing epidemiology of Staphylococcus aureus, the most common cause of surgical site infection in patients with open fractures. Although widespread emergence of methicillin-resistant Staphylococcus aureus (MRSA) has been described in both hospital and community settings, to date, no studies have addressed the need for prophylaxis against MRSA in patients with open fractures. Until well-designed randomized trials are conducted, we recommend that providers consider selecting antibiotics active against MRSA for open fracture prophylaxis based on the local prevalence of MRSA carriage and individualized risk factors.

Relationship between haematoma in femoral neck fractures contamination and early postoperative prosthetic joint infection

INTRODUCTION

Prosthetic joint infection (PJI) after femoral neck fracture is associated with a higher mortality, morbidity and economic costs. Although is well known that the presence of a post surgical haematoma is associated with infection, in our knowledge there are no articles evaluating the contamination of the femoral neck fracture haematoma and the possible relationship with early postoperative PJI. The aim of our study was to evaluate the prevalence of positive cultures from haematoma in patients with femoral neck fracture and the relationship with early PJI.

METHODS

A prospective observational study was performed. All patients who underwent hiphemiarthroplasty for a femoral neck fracture from April'08 to February'09 were included. Three samples were taken just after the arthrotomy, a tissue sample, a swab of haematoma and blood of haematoma inoculated into blood culture flasks. Patients received the standard prophylaxis.

RESULTS

A total of 109 patients were treated during this period in our center, 16 were excluded for mistakes during taking samples or for receiving extra antibiotic treatment after or before the surgery of the fracture. In 29 patients (31.2%) one or more intraoperative cultures were positive. Four patients developed an early PJI caused by Gram-negative bacilli (GNB) in all cases. The early PJI rate in the group of patients with negative intraopertive cultures was 3.1% while in the group with one or more positive cultures was 6.9% (p = 0.3). In 3 cases the haematoma was contaminated with a GNB. The PJI rate inpatients with intraoperative cultures positive for a GNB was 66.6% (2/3) while in the group of patients without a GNB the infection rate was 2.2% (2/89, p = 0.004, Fisher exact-test). Furthermore in these two patients the microorganism that caused the PJI was the same that had been isolated from the haematoma.

CONCLUSION

The haematoma in femoral neck fractures was contaminated in 31.2% of cases before surgery. The contamination of the haematoma with a GNB was associated with a higher risk of early postoperative PJI.

The prevalence of meticillin-resistant Staphylococcus aureus in long-term care facilities: is there a need for tailored glycopeptide prophylaxis?

Prophylactic antibiotics are effective in reducing the rate of surgical site infection (SSI). Cephalosporin antibiotics are recommended except for patients colonised with meticillin resistant staphylococcus aureus (MRSA), where glycopeptide antibiotics are indicated. However, in the trauma setting, the MRSA status is unknown prior to surgery.

Aim: To determine if the incidence of MRSA colonisation in trauma patients from long term care (LTC) warrants the use of empirical glycopeptide antibiotics.

Methods: A retrospective analysis of patients admitted with hip fractures was performed. The MRSA status of patient from LTC facilities and home was determined.

Results: The prevalence of MRSA colonisation in patients admitted from LTC facilities was 33.6%, compared to 3.6% for patients admitted from home, P < 0.001.

Our results suggest that risk of patients carrying MRSA is significantly higher for patients being admitted form LTC. This group of patients may benefit from empirical glycopeptide antibiotic when the MRSA status is unknown.

Methicillin-resistant Staphylococcus aureus in orthopaedic trauma

We have conducted a case-control study over a period of ten years comparing both deep infection with methicillin-resistant staphylococcus aureus (MRSA) and colonised cases with a control group.

Risk factors associated with deep infection were vascular diseases, chronic obstructive pulmonary disease, admission to a high-dependency or an intensive-care unit and open wounds. Those for colonisation were institutional care, vascular diseases and dementia. Older age was a risk factor for any MRSA infection. The length of hospital stay was dramatically increased by deep infection.

These risk factors are useful in identifying higher-risk patients who may be more susceptible to MRSA infection. A strategy of early identification and isolation may help to control its spread in trauma units.

Magnetic microsphere-based methods to study the interaction of teicoplanin with peptides and bacteria

Teicoplanin (teic) from Actinoplanes teichomyceticus is a glycopeptide antibiotic used to treat many gram-positive bacterial infections. Glycopeptide antibiotics inhibit bacterial growth by binding to carboxy-terminal D-Ala-D-Ala intermediates in the peptidoglycan of the cell wall of gram-positive bacteria. In this paper we report the derivatization of magnetic microspheres with teic (teic-microspheres). Fluorescence-based techniques have been developed to analyze the binding properties of the microspheres to two D-Ala-D-Ala terminus peptides. The dissociation constant for the binding of carboxyfluorescein-labeled D-Ala-D-Ala-D-Ala to teic on microspheres was established via fluorimetry and flow cytometry and was determined to be 0.5 x 10(-6) and 3.0 x 10(-6) mol L(-1), respectively. The feasibility of utilizing microparticles with fluorescence methods to detect low levels (the limit of bacterial detection was determined to be 30 colon-forming units; cfu) of gram-positive bacteria has been demonstrated. A simple microfluidic experiment is reported to demonstrate the possibility of developing microsphere-based affinity assays to study peptide-antibiotic interaction.