Institutional prescreening for detection and eradication of methicillin-resistant Staphylococcus aureus in patients undergoing elective orthopaedic surgery

Staphylococcus aureus screening and preoperative decolonisation with Mupirocin and Chlorhexidine to reduce the risk of surgical site infections in orthopaedic surgery: a pre-post study

BACKGROUND

Nasal carriage of Staphylococcus aureus is a risk factor for surgical site infections (SSI) in orthopaedic surgery. The efficacy of decolonisation for S. aureus on reducing the risk of SSI is uncertain in this speciality. The objective was to evaluate the impact of a nasal screening strategy of S. aureus and targeted decolonisation on the risk of S. aureus SSI.

METHODS

A retrospective pre-post and here-elsewhere study was conducted between January 2014 and June 2020 in 2 adult orthopaedic surgical sites (North and South) of a French university hospital. Decolonisation with Mupirocin and Chlorhexidine was conducted in S. aureus carriers starting February 2017 in the South site (intervention group). Scheduled surgical procedures for hip, knee arthroplasties, and osteosyntheses were included and monitored for one year. The rates of S. aureus SSI in the intervention group were compared to a historical control group (South site) and a North control group. The risk factors for S. aureus SSI were analysed by logistic regression.

RESULTS

A total of 5,348 surgical procedures was included, 100 SSI of which 30 monomicrobial S. aureus SSI were identified. The preoperative screening result was available for 60% (1,382/2,305) of the intervention group patients. Among these screenings, 25.3% (349/1,382) were positive for S. aureus and the efficacy of the decolonisation was 91.6% (98/107). The rate of S. aureus SSI in the intervention group (0.3%, 7/2,305) was not significantly different from the historical control group (0.5%, 9/1926) but differed significantly from the North control group (1.3%, 14/1,117). After adjustment, the risk factors of S. aureus SSI occurrence were the body mass index (ORaper unit, 1.05; 95%CI, 1.0-1.1), the Charlson comorbidity index (ORaper point, 1.34; 95%CI, 1.0-1.8) and operative time (ORaper minute, 1.01; 95%CI, 1.00-1.02). Having benefited from S. aureus screening/decolonisation was a protective factor (ORa, 0.24; 95%CI, 0.08-0.73).

CONCLUSIONS

Despite the low number of SSI, nasal screening and targeted decolonisation of S. aureus were associated with a reduction in S. aureus SSI.

General skin and nasal decolonization with octenisan® set before and after elective orthopedic surgery in selected patients at elevated risk for revision surgery and surgical site infections-a single-center, unblinded, superiority, randomized controlled trial (BALGDEC trial)

BACKGROUND

The preoperative body surface and nasal decolonization may reduce the risk of surgical site infections (SSI) but yields conflicting results in the current orthopedic literature.

METHODS

We perform a single-center, randomized-controlled, superiority trial in favor of the preoperative decolonization using a commercial product (octenidine® set). We will randomize a total number of 1000 adult elective orthopedic patients with a high risk for SSI and/or wound complications (age ≥ 80 years, chronic immune-suppression, American Society of Anesthesiologists score 3-4 points) between a decolonization (octenisan® wash lotion 1 × per day and octenisan® md nasal gel 2-3 × per day; during 5 days) and no decolonization. Decolonized patients will additionally fill a questionnaire regarding the practical difficulties, the completeness, and the adverse events of decolonization. The primary outcomes are SSI and revision surgeries for postoperative wound problems until 6 weeks postoperatively (or 1 year for surgeries with implants or bone). Secondary outcomes are unplanned revision surgeries for non-infectious problems and all adverse events. With 95% event-free surgeries in the decolonization arm versus 90% in the control arm, we formally need 2 × 474 elective orthopedic surgeries included during 2 years.

DISCUSSION

In selected adult orthopedic patients with a high risk for SSI, the presurgical decolonization may reduce postoperative wound problems, including SSI.

TRIAL REGISTRATION

ClinicalTrial.gov NCT05647252. Registered on 9 December 2022.

PROTOCOL VERSION

2 (5 December 2022).

Preoperative MRSA screening using a simple questionnaire prior elective total joint replacement

INTRODUCTION

The purpose of this study was to evaluate the management and results of our standarized protocol for preoperative identification of MRSA colonisation in patients undergoing primary total hip and knee replacement procedures.

METHODS

Following hospital protocol, between January 2016 and June 2019 37,745 patients awaiting elective joint replacement underwent a standardized questionnaire to assess the risk of MRSA infection, identifying patients requiring preoperative MRSA screening. An evaluation of the questionnaire identified effective questions for identifying infected patients. Furthermore, an analysis evaluated the impact of comorbidities or Charlson Comorbidity Index scores on positive MRSA colonization. Additionally, we evaluated the cost savings of targeted testing compared to testing all surgery patients.

RESULTS

Of the 37,745 patients, 8.057 (21.3%) were swabbed, with a total of 65 (0.81%) positive tests. From this group 27 (36.48%) who were treated were negative before surgery. Some of the questionnaire results were consistently associated with a higher chance of colonization, including hospitalization during the past year (47,7%), previous history of MRSA (44,6%), and agriculture or cattle farming related work (15,4%). By selectively testing high-risk patients identified through the questionnaire, we achieved a 79% reduction in costs compared to universal MRSA screening.

CONCLUSION

Our results suggest that the simple and standardized questionnaire is a valuable tool for preoperative screening, effectively identifying high-risk patients prone to MRSA colonisation. The risk of periprosthetic joint infection (PJI) and its associated sequelae may be reduced by this approach.

Preventive strategies to reduce the rate of periprosthetic infections in total joint arthroplasty; a comprehensive review

The increasing frequency of total hip (THA) and knee arthroplasties (TKA) is marred by the rise in periprosthetic joint infections (PJIs) and surgical site infections (SSIs), with PJIs incurring costs over $1.62 billion as of 2020 and individual case management averaging $90,000. SSIs additionally burden the U.S. healthcare economy with billions in expenses annually. PJI prevalence in primary THA and TKA ranges from 0.5% to 2.4%, spiking to 20% in revisions and representing 25% of TKA revision causes. Projections estimate up to 270,000 annual PJI cases by 2030. Often caused by gram-positive bacteria, particularly methicillin-resistant staphylococci, these infections demand preventive measures. This review dissects PJI prevention across preoperative, intraoperative, and perioperative phases, aligning with evidence-based CDC and WHO guidelines. Preoperative measures include managing diabetes, obesity, tobacco use, Staphylococcus aureus screening and nasal decolonization, nutritional optimization, and management of inflammatory arthropathies. Intraoperatively, antibiotic prophylaxis, skin preparation, operative room environmental controls, surgical technique precision, and irrigation options are scrutinized. Perioperative concerns focus on anticoagulation, blood management, and infection risk mitigation. Integrating these strategies promotes a patient-centric care model, aiming to reduce PJI incidence, improve patient outcomes, and increase care cost-effectiveness in joint arthroplasty.

Staphylococcus epidermidis joint isolates: Whole-genome sequencing demonstrates evidence of hospital transmission and common antimicrobial resistance

OBJECTIVE

We investigated genetic, epidemiologic, and environmental factors contributing to positive Staphylococcus epidermidis joint cultures.

DESIGN

Retrospective cohort study with whole-genome sequencing (WGS).

PATIENTS

We identified S. epidermidis isolates from hip or knee cultures in patients with 1 or more prior corresponding intra-articular procedure at our hospital.

METHODS

WGS and single-nucleotide polymorphism-based clonality analyses were performed, including species identification, in silico multilocus sequence typing (MLST), phylogenomic analysis, and genotypic assessment of the prevalence of specific antibiotic resistance and virulence genes. Epidemiologic review was performed to compare cluster and noncluster cases.

RESULTS

In total, 60 phenotypically distinct S. epidermidis isolates were identified. After removal of duplicates and impure samples, 48 isolates were used for the phylogenomic analysis, and 45 (93.7%) isolates were included in the clonality analysis. Notably, 5 S. epidermidis strains (10.4%) showed phenotypic susceptibility to oxacillin yet harbored mecA, and 3 (6.2%) strains showed phenotypic resistance despite not having mecA. Smr was found in all isolates, and mupA positivity was not observed. We also identified 6 clonal clusters from the clonality analysis, which accounted for 14 (31.1%) of the 45 S. epidermidis isolates. Our epidemiologic investigation revealed ties to common aspirations or operative procedures, although no specific common source was identified.

CONCLUSIONS

Most S. epidermidis isolates from clinical joint samples are diverse in origin, but we identified an important subset of 31.1% that belonged to subclinical healthcare-associated clusters. Clusters appeared to resolve spontaneously over time, suggesting the benefit of routine hospital infection control and disinfection practices.

Topical Vancomycin for Prevention of Surgical Site Infection in Cranial Surgeries: Results of an Updated Systematic Review, Meta-Analysis and Meta-Regression

Background

Surgical site infection (SSI) rates (1-9%) remain high despite the widespread adoption of infection control bundles. Topical vancomycin has emerged as an effective strategy to reduce the rate of SSI in patients undergoing spinal surgery including instrumentation. However, its use and efficiency in cranial neurosurgery is not well established. The aim of this study is to study the efficacy of topical vancomycin in cranial neurosurgery.

Methods

A systematic search was performed according to Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) guidelines. Data regarding type of surgery, use of implants, the dose of vancomycin, technique of administration in each study, outcomes, rate of SSI, and the interval between surgery and SSI; possible complications related to antibiotic use were collected.

Results

A total of 12 studies were included in the qualitative analysis with 3,446 patients. SSI developed in 1.6% of the patients in the vancomycin group as compared to 5.28% in the control group. The pooled risk ratio was 0.24 with 95% CI: 0.12-0.51 (P-value: <0.00001). The difference between the subgroups was significant (P-value: < 0.00001). The number needed to treat (NNT) was 27.2. The studies showed low heterogeneity with an I2 of 24%. Meta-regression analysis showed that the number of patients in a study, duration of follow-up, and year of publication did not contribute significantly to effect size.

Conclusion

The limited systemic absorption of vancomycin and broad-spectrum led to its widespread applicability in the prevention of SSI in all types of cranial neurosurgery. Cases with implantable pulse generators, cranioplasty, and cerebrospinal fluid (CSF) diversion procedures have all demonstrated their unequivocal effectiveness.

Cost-effectiveness and clinical utility of universal pre-admission MRSA screening in total joint arthroplasty patients

BACKGROUND

For patients undergoing total joint arthroplasty (TJA), pre-admission meticillin-resistant Staphylococcus aureus (MRSA) nasal screening has been widely adopted to prevent postoperative joint infection. However, screening cost-effectiveness and clinical utility have not been adequately evaluated.

AIM

To assess the MRSA infection rate, associated costs, and costs of screening at our institution, before and after screening implementation.

METHODS

This was a retrospective cohort study examining patients who underwent TJA at a health system in New York State, between 2005 and 2016. Patients were divided into the 'no-screening' group if the operation occurred prior to adoption of the MRSA screening protocol in 2011 and the 'screening' group if afterwards. The number of MRSA joint infections, cost of each infection, and costs associated with preoperative screening were recorded. Fisher's exact test and cost comparison analysis were performed.

FINDINGS

The no-screening group had four MRSA infections in 6088 patients over a seven-year period, whereas the screening group had two in 5177 patients over five years. Fisher's exact test showed no significant association between screening and MRSA infection rate (P = 0.694). The cost of postoperative MRSA joint infection treatment was US$40,919.13 per patient, whereas annual nasal screening was US$103,999.97.

CONCLUSION

At our institution, MRSA screening had little impact on infection rates and led to increased costs, with 2.5 MRSA infections required annually to meet the costs of screening. Therefore, the screening protocol may be best suited for high-risk populations, rather than the average TJA patient. The authors recommend a similar clinical utility and cost-effectiveness analysis at other institutions implementing MRSA screening programmes.

Whole-Genome Sequencing-Based Screening of MRSA in Patients and Healthcare Workers in Public Hospitals in Benin

Methicillin-resistant Staphylococcus aureus (MRSA) constitutes a serious public health concern, with a considerable impact on patients' health, and substantial healthcare costs. In this study, patients and healthcare workers (HCWs) from six public hospitals in Benin were screened for MRSA. Strains were identified as MRSA using conventional microbiological methods in Benin, and confirmed using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry in Belgium. Whole-genome sequencing (WGS) was used on the confirmed MRSA isolates, to characterize their genomic content and study their relatedness. Amongst the 305 isolates (304 wound swabs and 61 nasal swabs) that were collected from patients and HCWs, we detected 32 and 15 cases of MRSA, respectively. From this collection, 27 high-quality WGS datasets were obtained, which carried numerous genes and mutations associated with antimicrobial resistance. The mecA gene was detected in all the sequenced isolates. These isolates were assigned to five sequence types (STs), with ST8 (55.56%, n = 15/27), ST152 (18.52%, n = 5/27), and ST121 (18.52%, n = 5/27) being the most common. These 27 isolates carried multiple virulence genes, including the genes encoding the Panton-Valentine leukocidin toxin (48.15%, n = 13/27), and the tst gene (29.63%, n = 8/27), associated with toxic shock syndrome. This study highlights the need to implement a multimodal strategy for reducing the risk of the cross-transmission of MRSA in hospitals.

MRSA screening: incidence and maternal postpartum outcomes in an obstetric population at a tertiary care center

PURPOSE

To assess the incidence of MRSA positive patients in pregnancy, as well as the postpartum outcomes in MRSA positive patients.

METHODS

This is a retrospective cohort study of women who underwent universal MRSA universal at a tertiary medical center. A MRSA swab was routinely collected as part of the patient's prenatal care at 35-37 weeks gestation or on admission to labor and delivery. Demographic information and decolonization antibiotics were collected by electronic medical record review, using ICD-9 codes. Outcome data were collected, including mode of delivery, hospital length of stay, endometritis, wound cellulitis, and wound infection. p < 0.05 was considered significant. A univariate logistic regression and a multivariable binary logistic regression model were used to analyze the strength of association between outcomes and MRSA status. Statistical analysis was performed with SAS, version 9.4.

RESULTS

The incidence of MRSA during the 4 year study period was 1.9% (82 MRSA positive out of 4369 total patients). 90.2% (74/82) of MRSA positive patients received decolonization antibiotics. No difference was noted in mode of delivery. Logistic regression failed to identify any significant differences in other relevant outcomes for MRSA positive women including endometritis 1.1 (0.1-17.5) [positive 0, versus negative 0.6% (n = 24)], wound cellulitis 5.9 (0.4-82.1) positive 0, versus negative 0.1% (Gorwitz et al. in J Infect Dis 197:1226-1234, 2008) and wound infection 3.3 (0.6-16.9) [positive 1.2%, versus negative 0.5% ( in Am J Infect Control 32:470-85, 2004)] when compared to MRSA negative women.

CONCLUSION

When universal MRSA screening was performed at an academic tertiary care center, the overall incidence of MRSA was low. MRSA positive and subsequently decolinzed patients did not have any identified increase in postpartum infectious morbidity, as compared to MRSA negative patients.

Positive Preoperative Colonization With Methicillin Resistant Staphylococcus Aureus Is Associated With Inferior Postoperative Outcomes in Patients Undergoing Total Joint Arthroplasty

BACKGROUND

The impact of preoperative nasal colonization with methicillin resistant staphylococcus aureus (MRSA) on total joint arthroplasty (TJA) outcomes is not well understood. This study aimed to evaluate complications following TJA based on patients' preoperative staphylococcal colonization status.

METHODS

We retrospectively analyzed all patients undergoing primary TJA between 2011 and 2022 who completed a preoperative nasal culture swab for staphylococcal colonization. Patients were 1:1:1 propensity matched using baseline characteristics, and stratified into 3 groups based on their colonization status: MRSA positive (MRSA+), methicillin sensitive staphylococcus aureus positive (MSSA+), and MSSA/MRSA negative (MSSA/MRSA-). All MRSA+ and MSSA + underwent decolonization with 5% povidone iodine, with the addition of intravenous vancomycin for MRSA + patients. Surgical outcomes were compared between groups. Of the 33,854 patients evaluated, 711 were included in final matched analysis (237 per group).

RESULTS

The MRSA + TJA patients had longer hospital lengths of stay (P = .008), were less likely to discharge home (P = .003), and had higher 30-day (P = .030) and 90-day (P = .033) readmission rates compared to MSSA+ and MSSA/MRSA-patients, though 90-day major and minor complications were comparable across groups. MRSA + patients had higher rates of all-cause (P = .020), aseptic (P = .025) and septic revisions (P = .049) compared to the other cohorts. These findings held true for both total knee and total hip arthroplasty patients when analyzed separately.

CONCLUSION

Despite targeted perioperative decolonization, MRSA + patients undergoing TJA have longer lengths of stay, higher readmission rates, and higher septic and aseptic revision rates. Surgeons should consider patients' preoperative MRSA colonization status when counseling on the risks of TJA.

National surgical antibiotic prophylaxis guideline in Singapore

Introduction: Institutional surgical antibiotic prophylaxis (SAP) guidelines are in place at all public hospitals in Singapore, but variations exist and adherence to guidelines is not tracked consistently. A national point prevalence survey carried out in 2020 showed that about 60% of surgical prophylactic antibiotics were administered for more than 24 hours. This guideline aims to align best practices nationally and provides a framework for audit and surveillance. Method: This guideline was developed by the National Antimicrobial Stewardship Expert Panel’s National Surgical Antibiotic Prophylaxis Guideline Development Workgroup Panel, which comprises infectious diseases physicians, pharmacists, surgeons and anaesthesiologists. The Workgroup adopted the ADAPTE methodology framework with modifications for the development of the guideline. The recommended duration of antibiotic prophylaxis was graded according to the strength of consolidated evidence based on the scoring system of the Singapore Ministry of Health Clinical Practice Guidelines. Results: This National SAP Guideline provides evidence-based recommendations for the rational use of antibiotic prophylaxis. These include recommended agents, dose, timing and duration for patients undergoing common surgeries based on surgical disciplines. The Workgroup also provides antibiotic recommendations for special patient population groups (such as patients with β-lactam allergy and patients colonised with methicillin-resistant Staphylococcus aureus), as well as for monitoring and surveillance of SAP. Conclusion: This evidence-based National SAP Guideline for hospitals in Singapore aims to align practices and optimise the use of antibiotics for surgical prophylaxis for the prevention of surgical site infections while reducing adverse events from prolonged durations of SAP. Keywords: Antibiotic prophylaxis duration, antimicrobial resistance, antimicrobial stewardship, hospital-acquired infection, surgical site infections

The Utility of Perioperative Products for the Prevention of Surgical Site Infections in Total Knee Arthroplasty and Lower Extremity Arthroplasty: A Systematic Review

Surgical site infections (SSIs) are among the most prevalent and devastating complications following lower extremity total joint arthroplasty (TJA). Strategies to reduce the rates can be divided into preoperative, perioperatives, and postoperative measures. A multicenter trial is underway to evaluate the efficacy of implementing a bundled care program for SSI prevention in lower extremity TJA including: (1) nasal decolonization; (2) surgical skin antisepsis; (3) antimicrobial incise draping; (4) temperature management; and (5) negative-pressure wound therapy for selected high-risk patients. The purposes of this systematic review were to provide a background and then to summarize the available evidence pertaining to each of these SSI-reduction strategies with special emphasis on total knee arthroplasty. A systematic review of the literature was conducted in accordance with the 2009 Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement guidelines. Five individual literature searches were performed to identify studies evaluating nasal decolonization temperature management, surgical skin antisepsis, antimicrobial incise draping, and negative-pressure wound therapy. The highest level of evidence reports was used in each product review, and if there were insufficient arthroplasty papers on the particular topic, then papers were further culled from the surgical specialties to form the basis for the review. There was sufficient literature to assess all of the various prophylactic and preventative techniques. All five products used in the bundled program were supported for use as prophylactic agents or for the direct reduction of SSIs in both level I and II studies. This systematic review showed that various pre-, intra-, and postoperative strategies are efficacious in decreasing the risks of SSIs following lower extremity TJA procedures. Thus, including them in the armamentarium for SSI-reduction strategies for hip and knee arthroplasty surgeons should decrease the incidence of infections. We expect that the combined use of these products in an upcoming study will support these findings and may further enhance the reduction of total knee arthroplasty SSIs in a synergistic manner.

Lack of association of post-discharge prophylactic antibiotics with decreased risk of surgical site infection following spinal fusion

OBJECTIVES

To determine the prevalence and factors associated with post-discharge prophylactic antibiotic use after spinal fusion and whether use was associated with decreased risk of surgical site infection (SSI).

METHODS

Persons aged 10-64 years undergoing spinal fusion between 1 January 2010 and 30 June 2015 were identified in the MarketScan Commercial Database. Complicated patients and those coded for infection from 30 days before to 2 days after the surgical admission were excluded. Outpatient oral antibiotics were identified within 2 days of surgical discharge. SSI was defined using ICD-9-CM diagnosis codes within 90 days of surgery. Generalized linear models were used to determine factors associated with post-discharge prophylactic antibiotic use and with SSI.

RESULTS

The cohort included 156 446 fusion procedures, with post-discharge prophylactic antibiotics used in 9223 (5.9%) surgeries. SSIs occurred after 2557 (1.6%) procedures. Factors significantly associated with post-discharge prophylactic antibiotics included history of lymphoma, diabetes, 3-7 versus 1-2 vertebral levels fused, and non-infectious postoperative complications. In multivariable analysis, post-discharge prophylactic antibiotic use was not associated with SSI risk after spinal fusion (relative risk 0.98; 95% CI 0.84-1.14).

CONCLUSIONS

Post-discharge prophylactic oral antibiotics after spinal fusion were used more commonly in patients with major medical comorbidities, more complex surgeries and those with postoperative complications during the surgical admission. After adjusting for surgical complexity and infection risk factors, post-discharge prophylactic antibiotic use was not associated with decreased SSI risk. These results suggest that prolonged prophylactic antibiotic use should be avoided after spine surgery, given the lack of benefit and potential for harm.

Building a Center for Abdominal Core Health: The Importance of a Holistic Multidisciplinary Approach

BACKGROUND

This article seeks to be a collection of evidence and experience-based information for health care providers around the country and world looking to build or improve an abdominal core health center. Abdominal core health has proven to be a chronic condition despite advancements in surgical technique, technology, and equipment. The need for a holistic approach has been discussed and thought to be necessary to improve the care of this complex patient population.

METHODS

Literature relevant to the key aspects of building an abdominal core health center was thoroughly reviewed by multiple members of our abdominal core health center. This information was combined with our authors' experiences to gather relevant information for those looking to build or improve a holistic abdominal core health center.

RESULTS

An abundance of publications have been combined with multiple members of our abdominal core health centers members experience's culminating in a wide breadth of information relevant to those looking to build or improve a holistic abdominal core health center.

CONCLUSIONS

Evidence- and experience-based information has been collected to assist those looking to build or grow an abdominal core health center.

Screening of MRSA colonization in patients undergoing total joint arthroplasty

Background

Periprosthetic infection is commonly caused by Staphylococcus aureus and, if resistant to methicillin (MRSA), is associated with increase in severity and costs to patient and healthcare systems. MRSA colonizes 1-5% of the population, therefore using a screening and decolonisation protocol the risk of periprosthetic infection could be reduced. The objective of our study is to report the results of a preoperative MRSA screening and management protocol utilised at our hospital.

Methods

All patients undergoing a total joint arthroplasty at our hospital were preoperatively screened for MRSA colonization with swab samples of five different locations. Exposure to risk factors were investigated in colonised patients and they were treated for 5 days prior surgery with nasal mupirocin, chlorhexidine sponges and oral tablets.

Results

During the 48 months of the study, MRSA colonisation was identified in 22 (1.01%) of 2188 patients operated. The culture was positive only in the nasal swab in 55 patients. In five patients the nasal culture was negative, but they had another positive swab culture (three in the groin and two perianal). None of the patients reported a history of recent antibiotic treatment or hospitalization.

Conclusion

At our institution, the prevalence of MRSA colonisation is 1.01% in patients undergoing hip and knee arthroplasty. Interestingly, our screening protocol included samples from five different anatomic locations, and it is important to highlight that we found patients with negative nares culture and positive cultures in other locations. Therefore, the number of carriers may be underdiagnosed if only nasal samples are obtained.

Level of evidence

IV.

Risk of methicillin-resistant staphylococcus aureus prosthetic joint infection in elective total hip and knee arthroplasty following eradication therapy

BACKGROUND

Prosthetic joint infection (PJI) is a devastating complication requiring prolonged treatment and multiple operations, leading to significant morbidity for the patient. Patients are routinely tested for methicillin-resistant staphylococcus aureus (MRSA) colonisation. MRSA positive patients are given eradication therapy. We hypothesise that patients who are MRSA positive pre-operatively, have increased risk of developing PJI.

AIM

To identify deep wound infection (PJI) rates in patients who are colonised MRSA positive compared with those who are not colonised; and long term clinical and radiological outcomes.

METHODS

All patients who underwent total hip and knee replacements (THR/TKR) between December 2009 and December 2019 were identified. Patients who were also identified as being MRSA positive at pre-operative assessment were then selected. Confirmation of prescribing eradication treatment was recorded. Patient records, including consultation letters, operation notes and microbiology results were reviewed retrospectively. Comparison of outcomes for each MRSA positive patient was made with 2 MRSA negative patients undergoing the same operation of a similar age by the same consultant.

RESULTS

Screening identified 42 knee and 32 hip arthroplasty patients as MRSA positive, 84 MRSA negative knee and 64 hip patients were reviewed. Patients were matched with medical co-morbidities in each group. Mean follow up was 5 years. PJI was identified in 4/32 (12.5%) of THR MRSA positive and 3/42 (7%) of TKR patients. All patients had PJI within one year of surgery.

CONCLUSION

MRSA positive patients are given eradication therapy routinely. However, no confirmation of eradication is sought. Patients who have MRSA colonisation pre-operatively, in our study had a significantly increased risk of PJI, when compared to negative patients. We would recommend establishing true eradication after treatment prior to arthroplasty.

High rate of infection eradication following cementless one-stage revision hip arthroplasty with an antibacterial hydrogel coating

PURPOSE

We conducted a retrospective study to evaluate the outcomes of one-stage revision total hip arthroplasty (THA) following periprosthetic joint infection (PJI) in terms of eradication of the infection, improvement of pain and joint function. We hypothesized that this treatment strategy could lead to satisfying results in selected patients after preoperative microorganism isolation.

METHODS

Ten patients underwent cementless one-stage revision hip arthroplasty with antibacterial hydrogel coating for the treatment of an infected THA. Inclusion criteria were: the presence of a known organism with known sensitivity, patients non-immunocompromised with healthy soft tissues with minimal or moderate bone loss. Mean age at surgery was 69.4 years. Assessment included objective examination, Harris hip score, visual analog scale pain score, standard X-rays.

RESULTS

At a mean follow-up of 3.1 years (range, 2-5 years), none of the patients had clinical or radiographic signs suggesting recurrent infection. Follow-up examination showed significant improvement of all variables compared to pre-operative values (p < 0.05). Radiographs did not show progressive radiolucent lines or change in the position of the implant.

CONCLUSIONS

One-stage revision THA with antibacterial hydrogel coated implants represents a safe and effective procedure providing infection eradication and satisfying subjective functional outcomes in selected patients.

Is Preoperative Staphylococcus aureus Screening and Decolonization Effective at Reducing Surgical Site Infection in Patients Undergoing Orthopedic Surgery? A Systematic Review and Meta-Analysis With a Special Focus on Elective Total Joint Arthroplasty

BACKGROUND

Staphylococcus aureus is a major pathogen implicated in orthopedic infections worldwide. Preoperative decolonization has been promoted but different strategies present mixed results. Thus, the goals of this study are to determine (1) whether S aureus screening and/or decolonization is effective at reducing surgical site infection in orthopedic surgery, (2) with a special focus on elective total joint arthroplasty (TJA), and (3) which preoperative S aureus screening/treatment strategy is most cost-effective for TJA.

METHODS

PubMed, Ovid MEDLINE, and Cochrane databases were searched on January 1, 2020, using a systematic strategy. We included papers with data comparing surgical site infection and periprosthetic joint infection rate in orthopedic surgery and/or elective total hip and knee arthroplasty patients before/after S aureus screening and/or decolonization protocol and papers evaluating the cost-effectiveness of different S aureus screening/treatment strategies.

RESULTS

A total of 1260 papers were screened, and 32 papers were ultimately included. Results showed an increased risk of developing any infection (relative risk [RR] = 1.71 ± 0.16) and S aureus infection (RR = 2.79 ± 0.45) after orthopedic surgery without previous nares and whole-body decolonization. Focusing exclusively on elective TJA, there was an increased risk of developing any infection (RR = 1.70 ± 0.17) and S aureus infection (RR = 2.18 ± 0.41) if no decolonization is performed. All strategies appeared to be cost-effective, although universal decolonization without screening seemed to be the most advantageous.

CONCLUSION

Preoperative S aureus screening/decolonization protocol lowered the risk of infection after elective orthopedic and TJA surgeries. However, further studies are needed to determine optimal clinical and cost-effective methodologies.

What is the most cost-effective strategy for nasal screening and Staphylococcus aureus decolonization in patients undergoing total hip arthroplasty?

Background

To reduce periprosthetic joint infection after total hip arthroplasty (THA), several nasal screening and decolonization strategies for methicillin-resistant Staphylococcus aureus (MRSA) and methicillin-sensitive Staphylococcus aureus (MSSA) have been performed. These include universal decolonization (UD; i.e., no screening and decolonization for all patients), universal screening and target decolonization (US; i.e., screening for all patients and decolonization for bacterial positive patients), and target screening and decolonization (TS; i.e., screening and decolonization for high-risk populations only). Although TS is the most cost-effective strategy, useful risk factors must be identified. The purpose of this study was to evaluate the presence of predictive factors that enable the TS strategy to be successfully implemented and to compare the costs of each strategy.

Methods

A total of 1654 patients scheduled for primary or revision THA (1464 female, 190 male; mean age 64 years) were screened prior to surgery for bacterial colonization of the nasal mucosa. Risk factors for positive MRSA and S. aureus (including both MRSA and MSSA) tests were analyzed according to the following parameters: sex, age ≥ 80 years, body mass index ≥ 30 kg/m², antibiotic use within 3 years, corticosteroid use, serum albumin < 3.5 g/dL, glomerular filtration rate < 50 mL/min, presence of brain, thyroid, cardiac, or pulmonary disease, diabetes, asthma, smoking status, and whether revision surgery was performed. The average cost of each strategy was calculated.

Results

In total, 29 patients (1.8 %) tested positive for MRSA and 445 (26.9 %) tested positive for S. aureus. No parameters were identified as independent risk factors for MRSA and only female sex was identified as a risk factor for S. aureus (p = 0.003; odds ratio: 1.790; 95 % confidence interval: 1.210–2.640). The average cost of each strategy was 1928.3 yen for UD, 717.6 yen for US, and 717.6 yen for TS (for eradicating MRSA), and 1928.3 yen for UD, 1201.6 yen for US, and 1160.4 yen for TS (for eradicating S. aureus).

Conclusions

No useful predictive parameters for implementing the TS strategy were identified. Based on cost implications, US is the most cost-effective strategy for THA patients.

Efficacy of preoperative screening and decolonization for staphylococcus aureus in total joint arthroplasty: A meta-analysis

The purpose of this study is to conduct a meta-analysis to evaluate the efficacy of screening and decolonization protocol for Staphylococcus aureus (SA) in total joint arthroplasty (TJA). We systematically searched the electronic databases of PubMed, Embase and Cochrane databases for relevant literatures from January 2000 to September 2020. The outcomes were colonization rate, total-surgical site infection (SSI) rate, SA-SSI rate and methicillin-resistant Staphylococcus aureus (MRSA)-SSI rate. All calculations and statistical tests were performed using Stata 14.0 software. A total of 12 studies were eligible in this study. Compared with control group, the screening and decolonization group had lower risks in total-SSI (risk ratio (RR) = 0.52; 95% confidence interval (CI): 0.40-0.67), SA-SSI (RR = 0.48; 95% CI: 0.32-0.72) and MRSA-SSI (RR = 0.45; 95% CI: 0.21-0.96). The nasal SA colonization was found to be associated with higher accidences of SSI involving total-SSI (RR = 1.49; 95% CI: 1.02-2.18), SA-SSI (RR = 2.51; 95% CI: 0.97-6.50) and MRSA-SSI (RR = 7.84; 95% CI: 1.67-36.79). The colonization rate of SA was significantly reduced after decolonization. No difference was observed between universal decolonization and screening-based decolonization. In conclusion, colonization of SA is associated with increased risk of SSI in TJA. Screening and decolonization protocol are proven to be effective to reduce colonization of SA and present protective effects against SSI in TJA. Moreover, universal decolonization protocol is non-inferior to screening-based decolonization.

[Risk factors for multiple debridements of the patients with deep incisional surgical site infection after spinal surgery]

OBJECTIVE

To investigate the risk factors that contribute to multiple debridements in patients suffering from deep incisional surgical site infection after spinal surgery and advise medical personnel to pay special attention to these risk factors.

METHODS

We retrospectively enrolled 84 patients who got deep incisional surgical site infection after spinal surgery from Jan. 2012 to Dec. 2017. The infections occurred within 30 days after the surgery, and the identification met the criteria of deep incisional surgical site infection of Centers of Disease Control (CDC). Early debridement with first stage closure of the wound and a continuous inflow-outflow irrigation system was used, and reasonable antibiotics were chosen according to the bacterial culture results. During the treatment, the vital signs, clinical manifestations, blood test results, drainage fluid colour and bacterial culture results were acquired. If the infection failed to be controlled or relapsed, a second debridement was performed. Of the 84 cases, 60 undergwent single debridement which included 36 male cases and 24 female cases, and the age ranged from 36 to 77 years, with a mean of 57.2 years. Twenty four had multiple debridements (twice in 14 cases, three times in 6 cases, four times in 1 case, five times in 2 cases, six times in 1 cases) which included 17 male cases and 7 female cases, and the age ranged from 21 to 70 years, with a mean of 49.5 years. Risk factors that predispose patients to multiple debridements were identified using univariate analysis. Risk factors with P values less than 0.05 in univariate analysis were included together in a multivariate Logistic regression model using back-forward method.

RESULTS

Multiple debridements were performed in 28.6% of all cases. The hospital stay of multiple debridements group was (82.4±46.3) days compared with (40.4±31.5) days in single debridement group (P=0.018). Instrumentation was removed in 6 cases in multiple debridements group and 4 cases in single debridement group (P=0.049). Flap transplantation was performed in 7 cased in multiple debridements group while none in single debridement group (P < 0.001). Diabetes, primary operation duration longer than 3 hours, primary operation blood loss more than 400 mL, bacteriology examination results, distant site infection were significantly different between the two groups in univariate analysis. In multivariate analysis, primary operation duration longer than 3 hours (OR=3.60, 95%CI: 1.12-11.62), diabetes (OR=3.74, 95%CI: 1.06-13.22), methicillin-resistant Staphylococcus aureus (MRSA) infected (OR=16.87, 95%CI: 2.59-109.73) were the most important risk factors related to multiple debridements in the patients with deep incisional surgical site infection after spinal surgery.

CONCLUSION

Diabetes, primary operation duration more than 3 hours, MRSA infected are independent risk factors for multiple debridements in patients suffering from deep incisional surgical site infection after spinal surgery. Special caution and prophylaxis interventions are suggested for these factors.

Preoperative Staphylococcus aureus screening and eradication

AIMS

Preoperative nasal Staphylococcus aureus screening and eradication reduces surgical site infections (SSIs) but its impact on reducing early prosthetic joint infection (PJI) remains controversial. This study aims to assess the effect of preoperative nasal S. aureus screening and eradication on the incidence of early PJI in general and S. aureus-induced early PJI.

METHODS

All primary total hip arthroplasties (THA) and total knee arthroplasties (TKA) performed from January 2006 to April 2018 were retrospectively reviewed for the incidence of early PJI. Demographic parameters, risk factors for PJI (American Society of Anaesthesiologists classification, body mass index, smoking status, and diabetes mellitus) and implant types were collected. A preoperative screening and eradication protocol for nasal colonization of S. aureus was introduced in October 2010. The incidence of early PJI was compared before and after the implementation of the protocol. Missing data were imputed via multiple imputation by chained equations. Inverse probability weighting was used to account for differences between patients in both groups. Weighted univariate logistic regression was used to evaluate the incidence of early PJI for both groups.

RESULTS

In total, 10,486 THAs and TKAs were performed in the research period. After exclusion, a cohort of 5,499 screened cases and 3,563 non-screened cases were available for analysis. Overall, no significant reduction in early PJI was found in the screened group (odds ratio (OR) 0.78, 95% confidence interval (CI) 0.55 to 1.11; p = 0.173). However, the incidence of S. aureus-induced PJI was significantly reduced (OR 0.58, 95% CI 0.36 to 0.92; p = 0.027) in the screened group.

CONCLUSION

A preoperative nasal S. aureus screening and eradication protocol did not significantly reduce the overall incidence of early PJI after THA or TKA. However, a decreased incidence of S. aureus-induced early PJI was established. These findings can help to establish better consensus around the value of these screening protocols. Cite this article: Bone Joint J 2020;102-B(10):1341-1348.

Does Preoperative Decolonization Reduce Surgical Site Infections in Elective Orthopaedic Surgery? A Prospective Randomized Controlled Trial

BACKGROUND

Surgical site infections (SSIs) after elective orthopaedic surgery are very stressful for patients due to frequent rehospitalizations with reoperations and poorer functional outcomes. Prevention of such events is therefore crucial. Although an evidence-based consensus is still lacking, preoperative decolonization could decrease SSI. Specifically, more information is needed about the effect of a preoperative decolonization procedure on SSI proportions in both Staphylococcus aureus carriers and non-S. aureus carriers after general orthopaedic surgery.

QUESTIONS/PURPOSES

Our study addressed the following questions: (1) Does preoperative decolonization reduce the risk of SSI after general elective orthopaedic surgery in patients colonized with S. aureus? (2) Does preoperative decolonization reduce the risk of SSI among patients who are not colonized with S. aureus?

METHODS

In this prospective, randomized, single-blinded trial, we recruited patients undergoing general elective orthopaedic surgery in one tertiary care center in Switzerland. Between November 2014 and September 2017, 1318 of 1897 screened patients were enrolled. Patients were allocated into either the S. aureus carrier group (35%, 465 of 1318 patients) or the noncarrier group (65%, 853 of 1318 patients) according to screening culture results. In the S. aureus group, 232 patients were allocated to the intervention arm and 233 were allocated to the control arm. Intervention was 5 days of daily chlorhexidine showers and mupirocin nasal ointment twice a day. Of the 853 noncarriers, 426 were allocated to the intervention arm and 427 were allocated to the control arm. All patients in both groups were analyzed in an intention-to-treat manner. The primary endpoint was SSI occurrence at 90 days postoperative and the secondary endpoint was SSI occurrence at 30 days postoperative.The initial sample size calculation was made for the S. aureus carrier group. Based on the literature review, a 4% proportion of SSI was expected in the control group. Thus, 726 carriers would have been needed to detect a relative risk reduction of 80% with a power of 80% at a two-sided α-error of 0.048 (adjusted for interim analysis). Assuming carrier prevalence of 27%, 2690 patients would have been needed in total. An interim analysis was performed after including half of the targeted S. aureus carriers (363 of 726). Based on the low infection rate in the control group (one of 179), a new sample size of 15,000 patients would have been needed. This was deemed not feasible and the trial was stopped prematurely.

RESULTS

Among carriers, there was no difference in the risk of SSI between the intervention and control arms (decolonized SSI risk: 0.4% [one of 232], control SSI risk: 0.4% [one of 233], risk difference: 0.0% [95% CI -1.2% to 1.2%], stratified for randomization stratification factors; p > 0.999). For noncarriers, there was no difference in risk between the intervention and control arms (decolonized SSI risk: 0.2% [one of 426], control SSI risk: 0.2% [one of 247], stratified risk difference: -0.0% [95% CI -0.7 to 0.6]; p = 0.973).

CONCLUSIONS

We found no difference in the risk of SSI between the decolonization and control groups, both in S. aureus carriers and noncarriers. Because of the low event numbers, no definite conclusion about efficacy of routine preoperative decolonization can be drawn. The results, however, may be helpful in future meta-analyses.

LEVEL OF EVIDENCE

Level II, therapeutic study.

Methicillin-resistant Staphylococcus aureus colonization in patients undergoing primary total hip arthroplasty

Introduction. Nasal and skin colonization by methicillin-resistant Staphylococcus aureus (MRSA) are linked to a higher incidence of infection after total joint replacement. The prevalence of colonization is poorly defined in Latin American countries.Aim. The aim of the present study was to determine the prevalence of MRSA colonization in the nostrils and groin using real-time polymerase chain reaction (RT-PCR) in patients undergoing total hip arthroplasty (THA).Methodology. In this cross-sectional study, 146 patients undergoing THA between December 2015 and March 2017 in a tertiary-care university-affiliated hospital in Chile were screened for MRSA colonization before the procedure using RT-PCR independently in the nostrils and groin. Risk factors for colonization were documented.Results. Seven of the 146 (5 %) patients undergoing THA were carriers of MRSA in the nostrils and/or the groin. Recent antibiotic use was identified as a risk factor for colonization, OR=4.86 [95 % confidence interval (CI): 1.56-13.96]. Patients reporting at least one of the seven surveyed risk factors had an OR of 2.39 (95 % CI: 0.37-25.77) for colonization. MRSA colonization frequency was twofold higher in the groin as opposed to the nostrils (P=0.014).Conclusion. Five percent of the patients undergoing THA were identified as carriers of MRSA. Recent antibiotic use is a relevant risk factor for MRSA colonization in patients undergoing primary total hip arthroplasty.

Screening for and decolonization of Staphylococcus aureus carriers before total joint replacement is associated with lower S aureus prosthetic joint infection rates

BACKGROUND

Prosthetic joint infections (PJI) can be devastating postoperative complications after total joint replacement (TJR). The role of decolonization of Staphylococcus aureus carriers prior to surgery still remains unclear, and the most recent guidelines do not state a formal recommendation for such strategy. Our purpose was to seek further evidence supporting preoperative screening and S aureus decolonization in patients undergoing TJR.

METHODS

This was a quasiexperimental quality improvement study comparing a 5-year baseline of deep and organ-space PJIs (2005- 2010) to a 1-year intervention period (May 2015 to July 2016). The intervention consisted of nasal and throat screening for S aureus preoperatively and decolonization of carriers over 5 days prior to surgery.

RESULTS

Prior to the intervention, we identified 42 deep and/or organ-space PJIs in 8,505 patients undergoing TJR (0.5%). S aureus was the causal microorganism in 28 of 42 (66.6%) cases. During the intervention, 22.5% (424 of 1,883) of patients were S aureus carriers. The PJI rate was similar overall (0.4%, 7 of 1,883; odds ratio, 0.75; 95% confidence interval, 0.34-1.67; P = .58), but there was a significant reduction in S aureus PJI to only 1 case during the intervention (odds ratio, 0.15; 95% confidence interval, 0.004-0.94; P = .039).

CONCLUSIONS

Active screening for S aureus and decolonization of carriers prior to TJR was associated with a reduction in PJI due to S aureus, but no changes in overall PJI rates were observed.

Current Strategies in Prevention of Postoperative Infections in Spine Surgery

STUDY DESIGN

Narrative review.

OBJECTIVES

Postoperative surgical site infections (SSIs) are among the most common acute complications in spine surgery and have a devastating impact on outcomes. They can lead to increased morbidity and mortality as well as greater economic burden. Hence, preventive strategies to reduce the rate of SSIs after spine surgery have become vitally important. The purpose of this article was to summarize and critically analyze the available evidence related to current strategies in the prevention of SSIs after spine surgery.

METHODS

A literature search utilizing Medline database was performed. Relevant studies from all the evidence levels have been included. Recommendations to decrease the risk of SSIs have been provided based on the results from studies with the highest level of evidence.

RESULTS

SSI prevention occurs at each phase of care including the preoperative, intraoperative, and postoperative periods. Meticulous patient selection, tight glycemic control in diabetics, smoking cessation, and screening/eradication of Staphylococcus aureus are some of the main preoperative patient-related preventive strategies. Currently used intraoperative measures include alcohol-based skin preparation, topical vancomycin powder, and betadine irrigation of the surgical site before closure. Postoperative infection prophylaxis can be performed by administration of silver-impregnated or vacuum dressings, extended intravenous antibiotics, and supplemental oxygen therapy.

CONCLUSIONS

Although preventive strategies are already in use alone or in combination, further high-level research is required to prove their efficacy in reducing the rate of SSIs in spine surgery before evidence-based standard infection prophylaxis guidelines can be built.

Can we reduce the number of MRSA screening site swabs in elective orthopedic patients?

BACKGROUND

Deep infection after routine elective orthopedic procedures can be catastrophic, leading to further surgery, loss of limb, disability, and risk of mortality. Ring-fencing elective orthopedic ward has been shown to significantly reduce the incidence of all postoperative infections especially with methicillin-resistant Staphylococcus aureus (MRSA). Our hospital's current MRSA screening is a four-site MRSA swabs.

OBJECTIVES

This study evaluates the possibility of reducing the number of MRSA swab sites as part of a quality improvement project.

STUDY DESIGN AND METHODS

Patients on the waiting list for elective orthopedic procedure in our trust who had an MRSA-positive swab from either four sites were analyzed over the time period from January 2012 to December 2014. Those without swabs from all four areas (nose, throat, axilla, and groin) were excluded. Positive swabs of different regions were recorded and compared.

RESULTS

There were 138 MRSA-positive patients, giving an incidence of 31 per 10,000 screen/year over that time period. Some patients ( n = 31, 22.5%) had a positive swab in more than one site. The positive sites were as follows: nose (69.60%, n = 96), groin (26.10%, n = 36), throat (25.30%, n = 35), and axilla (8.70%, n = 12). In our cohort, we would miss a significant proportion of positive patients if we change it to a two swab screening policy (26.8% for nose and axilla combination; 18.10% for nose and groin combination; and 15.20% for nose and throat). However, we would only miss 2.2% of cases for a nose, groin, and throat three-swab policy. There were also 11 instances, where a previously negative site become positive in the next swab.

CONCLUSION

A three-swab combination of nasal, throat, and groin swabs improves pickup rate of MRSA significantly compared to a two-swab policy and misses only 2.2% compared to a four-swab policy. Axilla swabbing does not make a significant difference to the results. Based on this study, the policy has now been changed from a four-swab to three-swab screening in our trust. This has now been audited four times and they were all negative. This has helped to reduce cost in terms of staff time and resources. We would not recommend screening only the previous positive site for the next repeat screening swabs as there is an 8% chance of missing MRSA carrier status.

Infection prevention in cervical spine surgery

Surgical site infections (SSI) following cervical spine surgery can lead to significant patient morbidity and costs. Prevention of SSIs is multifactorial and can be divided in to preoperative patient optimization and intraoperative surgical factors. We performed a literature review to identify methods that can be used to prevent SSI development specifically in the cervical spine. We also present specific surgical pearls and techniques that have the potential to significantly decrease rates of cervical SSIs.

Can nasal Staphylococcus aureus screening and decolonization prior to elective total joint arthroplasty reduce surgical site and prosthesis-related infections? A systematic review and meta-analysis

Background

Nasal Staphylococcus aureus (S. aureus) screening and decolonization has been widely used to reduce surgical site infections (SSIs) prior to total knee and hip arthroplasty (TKA and THA). However, it remains considerably controversial. The aim of this study was to ascertain whether this scheme could reduce SSIs and periprosthetic joint infections (PJIs) following elective primary total joint arthroplasty (TJA).

Methods

A systematic search was performed in MEDLINE, Embase, and the Cochrane Library until October, 2019. Outcomes of interest included SSI, PJI, superficial infection, and different bacterial species that caused infections. Data from eligible studies were then extracted and synthesized. Pooled odds ratios (OR) and 95% confidence intervals (CIs) were calculated. We also performed additional analyses to evaluate whether there were differences in postoperative SSIs caused by S. aureus or other bacteria.

Results

Nine studies were included in our meta-analysis. The pooled data elucidated that nasal S. aureus screening and decolonization dramatically mitigated the risk of SSI, PJI, and superficial infection compared to nondecolonization group. The analysis of bacterial species causing infection also showed that the S. aureus infections postoperative were significantly decreased in the decolonization group. However, there was no statistical difference in the SSI caused by other bacteria between the two groups.

Conclusion

S. aureus screening and decolonization prior to elective primary THA and TKA could significantly decrease the risk of SSI and PJI. However, more robust studies are needed to further evaluate the impact of S. aureus screening and decolonization on infection risk after TJA.

Companion and complementary diagnostics for infectious diseases

INTRODUCTION

Companion diagnostics (CDx) are important in oncology therapeutic decision-making, but specific regulatory-approved CDx for infectious disease treatment are officially lacking. While not approved as CDx, several ID diagnostics are used as CDx. The diagnostics community, manufacturers, and regulatory agencies have made major efforts to ensure that diagnostics for new antimicrobials are available at or near release of new agents.

AREAS COVERED

This review highlights the status of Complementary and companion diagnostic (c/CDx) in the infectious disease literature, with a focus on genotypic antimicrobial resistance testing against pathogens as a class of diagnostic tests.

EXPERT OPINION

CRISPR, sepsis markers, and narrow spectrum antimicrobials, in addition to current and emerging technologies, present opportunities for infectious disease c/CDx. Challenges include slow guideline revision, high costs for regulatory approval, lengthy buy in by agencies, discordant pharmaceutical/diagnostic partnerships, and higher treatment costs. The number of patients and available medications used to treat different infectious diseases is well suited to support competing diagnostic tests. However, newer approaches to treatment (for example, narrow spectrum antibiotics), may be well suited for a small number of patients, i.e. a niche market in support of a CDx. The current emphasis is rapid and point-of-care (POC) diagnostic platforms as well as changes in treatment.

Methicillin-Resistant Staphylococcus Aureus Carrier Rate in Orthopaedic Trauma Patients: A Prospective Cohort Study

OBJECTIVES

To identify the methicillin-resistant Staphylococcus aureus (MRSA) carrier rate among surgical patients on an orthopaedic trauma service and to determine whether screening is an effective tool for reducing postoperative MRSA infection in this population.

DESIGN

Prospective.

SETTING

Level 1 trauma center.

PATIENTS/PARTICIPANTS

Two hundred forty-eight patients with operatively managed orthopaedic trauma conditions during the study period. Two hundred three patients (82%) had acute orthopaedic trauma injuries. Forty-five patients (18%) underwent surgery for a nonacute orthopaedic trauma condition, including 36 elective procedures and 9 procedures to address infection.

INTERVENTION

MRSA screening protocol, preoperative antibiotics per protocol.

MAIN OUTCOME MEASUREMENTS

MRSA carrier rate, overall infection rate, MRSA infection rate.

RESULTS

Our screening captured 71% (175/248) of operatively treated orthopaedic trauma patients during the study period. The overall MRSA carrier rate was 3.4% (6/175). When separated by group, the acute orthopaedic trauma cohort had an MRSA carrier rate of 1.4% (2/143), and neither MRSA-positive patient developed a surgical site infection. Only one MRSA infection occurred in the acute orthopaedic trauma cohort. The nonacute group had a significantly higher MRSA carrier rate of 12.5% (4/32, P = 0.01), and the elective group had the highest MRSA carrier rate of 15.4% (4/26, P < 0.01). The odds ratio of MRSA colonization was 10.1 in the nonacute group (95% confidence interval, 1.87-75.2) and 12.8 for true elective group (95% confidence interval, 2.36-96.5) when compared with the acute orthopaedic trauma cohort.

CONCLUSIONS

There was a low MRSA colonization rate (1.4%) among patients presenting to our institution for acute fracture care. Patients undergoing elective surgery for fracture-related conditions such as nonunion, malunion, revision surgery, or implant removal have a significantly higher MRSA carrier rate (15.4%) and therefore may benefit from MRSA screening. Our results do not support routine vancomycin administration for orthopaedic trauma patients whose MRSA status is not known at the time of surgery.

LEVEL OF EVIDENCE

Prognostic Level II. See Instructions for Authors for a complete description of levels of evidence.

Surgical Site Infection Prevention Following Spine Surgery

STUDY DESIGN

Literature review.

OBJECTIVES

Surgical site infection (SSI) following spine surgery leads to significant patient morbidity, mortality, and increased health care costs. The purpose of this article is to identify risk factors and strategies to prevent SSIs following spine surgery, with particular focus on avoiding infections in posterior cervical surgery.

METHODS

We performed a literature review and synthesis to identify methods that can be used to prevent the development of SSI following spine surgery. Specific pearls for preventing infection in posterior cervical spine surgery are also presented.

RESULTS

SSI prevention can be divided into patient and surgeon factors. Preoperative patient factors include smoking cessation, tight glycemic control, weight loss, and nutrition optimization. Surgeon factors include screening and treatment for pathologic microorganisms, skin preparation using chlorhexidine and alcohol, antimicrobial prophylaxis, hand hygiene, meticulous surgical technique, frequent irrigation, intrawound vancomycin powder, meticulous multilayered closure, and use of closed suction drains.

CONCLUSION

Prevention of SSI following spine surgery is multifactorial and begins with careful patient selection, preoperative optimization, and meticulous attention to numerous surgical factors. With careful attention to various patient and surgeon factors, it is possible to significantly reduce SSI rates following spine surgery.

A two-part phase 1 study to establish and compare the safety and local tolerability of two nasal formulations of XF-73 for decolonisation of Staphylococcus aureus: A previously investigated 0.5mg/g viscosified gel formulation versus a modified formulation

OBJECTIVES

Successful decolonisation of nasal Staphylococcus aureus (SA) carriage by mupirocin is limited by increasing drug resistance. This randomised, open-label, phase 1 study compared the safety and local tolerability of two nasal formulations of XF-73, a novel porphyrinic antibacterial with rapid intrinsic activity against SA.

METHODS

The study was performed in 60 healthy adults. In Part 1, eight non-SA carriers were randomised to groups of four subjects each and were treated with XF-73 concentrations of 0.5mg/g 2% gel or 2.0mg/g 2% gel. In Part 2, 52 persistent SA carriers were randomised to groups of 13 subjects each and were treated with XF-73 concentrations of 0.5mg/g 2% gel, 2.0mg/g 2% gel, 0.5mg/g 4% gel or 4% viscosified placebo gel. Plasma pharmacokinetic and pharmacodynamic studies were performed. Antistaphylococcal activity was assessed as the presence/absence of SA and by quantification of colonisation using a semiquantitative scale (SA score).

RESULTS

56 subjects (8/8 from Part 1 and 48/52 from Part 2) completed the study, with 47/60 comprising the pharmacokinetic population and 48/60 the pharmacodynamic population. There was no measurable systemic absorption of XF-73. XF-73 treatment was associated with rapid reduction in SA score in all subjects. The most common treatment-emergent adverse events (TEAEs) were rhinorrhoea and nasal dryness (15.5% each in Parts 1 and 2). TEAEs were mild and resolved spontaneously.

CONCLUSION

XF-73 was well tolerated with minimal side effects at doses of 0.5mg/g 2% gel and 2.0mg/g 2% gel. These findings support further development of XF-73.

[Infections after reconstructive spinal interventions : How do I deal with them?]

BASICS

Postoperative surgical site infections of the spine have been described in up to 20% of patients and can result in serious consequences for the patient and substantial treatment costs. Typical bacteria often arise from skin or fecal flora. Various risk factors for infection have been described, including obesity, diabetes, high ASA scores, as well as intraoperative factors such as heavy blood loss, dural tears, or several revision procedures. Consequently, the prophylaxis with pre- and postoperative risk minimization is of particular importance.

TREATMENT

When an infection has developed, it is important to carry out early operative revision involving tissue debridement, lavage and acquiring microbiological samples for culture. If the infection presents early, the instrumentation can often be retained. Adjuvant measures such as negative pressure wound treatment may improve the outcome. In late-onset infections, due to the biofilm production on the instrument surface or in cases of implant loosening, one should attempt to remove the instrumentation, and in cases of instability replace it. This article deals with the current literature on the subject and provides an overview of the data with regard to peri- and postoperative infections.

PREVALENCE OF METHICILLIN-RESISTANT STAPHYLOCOCCUS AUREUS IN SPINAL SURGERY PATIENTS

ABSTRACT Objective The objective of this study was to determine the prevalence of patients with colonization of methicillin-resistant Staphylococcus aureus (MRSA) in the nasal mucosa, who underwent elective spinal procedures. Methods Retrospective study of the medical records of all patients submitted to elective procedures, totaling 125 individuals in the period of 2015 and 2017, performed by two spinal surgeons of the Orthopedics and Traumatology Service of Hospital Mater Dei, Belo Horizonte, Minas Gerais. The pre-operative investigation of MRSA consisted of the collection of a nasal swab for microbiological culture. Results Of the 125 patients evaluated, three (2.4%) showed positive results for MRSA nasal colonization. This prevalence is consistent with the international literature, that ranges from 1.5 to 5.9%. Of these patients none had infection of the surgical wound, probably due to the preoperative prophylactic measures. Conclusions Despite the limitations of the study, we found that the prevalence of carriers of this nasal MRSA population is similar to that of populations worldwide . Level of evidence III; Retrospective Study.

A Longitudinal Study of S. aureus Infection in a National Cohort of Surgical Patients

BACKGROUND

Postoperative infections are a common and often preventable complication of surgery. S. aureus is a prevalent organism cultured in these infections and is associated with morbidity, mortality, and increased healthcare utilization. However, the long-term burden of S. aureus infection in surgical patients is not well studied. The purpose of this retrospective observational study is to assess the incidence, time trend, and burden of S. aureus infection up to 1 year after surgery.

METHODS

We obtained manually-reviewed data from the VA Surgical Quality Improvement Program (VASQIP) to identify surgeries in all major specialties. These were combined with laboratory microbiology and pharmacy data to identify pneumonia and infections of the urinary tract, surgical site, and blood.

RESULTS

In the study population of 559,550 patients, S. aureus incidence decreased each year, from 2.1% in 2008 to 1.1% in 2015. Among these, incidence of methicillin-resistant S. aureus (MRSA) infection decreased from 0.7% to 0.4%, and methicillin-susceptible S. aureus (MSSA) decreased from 1.4% to 0.7%. S. aureus infection was associated with increased length of stay, ED utilization, inpatient admissions, as well as a 4-fold increase in mortality.

CONCLUSIONS

This is one of the largest studies describing the long-term incidence of S. aureus in the surgical population of a national integrated healthcare system. We conclude that the burden of S. aureus infection extends well beyond the conventional 30-day postoperative window, and late infection should be included in assessing the effects of interventions.

Risk factors for Staphylococcus aureus colonization in a presurgical orthopedic population

BACKGROUND

Preoperative colonization with Staphylococcus aureus (SA) increases risk of surgical site infection. Screening for SA followed by skin and nasal decolonization can help to reduce the risk of postoperative infections. Risk factors for colonization are, however, not completely understood.

METHODS

A case-control study using questionnaires and patient demographics specifically designed to observe SA colonization risk factors in a presurgical orthopedic population. A total of 115 subjects with a positive preoperative screen for SA nasal colonization prior to orthopedic surgery completed a questionnaire to assess for SA risk factors: these subjects served as our cases. An additional 476 controls completed similar questionnaires. Data collected included demographic, health, and lifestyle information. Multivariable logistic regression was used to generate odds ratios (OR) for risk of SA colonization.

RESULTS

Several risk factors were identified. Male sex (OR 2.3; 95% confidence interval [CI], [1.4-3.8]) and diabetes (OR 3.8 [1.8-7.8]) significantly increased the risk of SA colonization. Older age, visiting public places (OR 0.2 [0.1-0.3]), recent antibiotic use (OR 0.2 [0.1-0.6]), and the presence of facial hair (OR 0.3 [0.1-0.6]) significantly lowered the risk of SA colonization.

CONCLUSIONS

By identifying patients who may be at greater risk of SA colonization, we can better streamline our presurgical techniques to help reduce risk of surgical site infections and improve patient outcomes.

Should Routine Methicillin-Resistant Staphylococcus aureus (S. aureus), or MRSA, Screening Be in Place Prior to Total Ankle Arthroplasty (TAA)?

RECOMMENDATION

Unknown. The role of screening for methicillin-resistant Staphylococcus aureus (MRSA) and decolonization prior to total ankle arthroplasty (TAA) remains unclear. Further data are needed to support this practice in TAA, which can be costly and logistically difficult to implement.

LEVEL OF EVIDENCE

Consensus.

DELEGATE VOTE

Agree: 100%, Disagree: 0%, Abstain: 0% (Unanimous, Strongest Consensus).

Prevalence and Risk Factors for Positive Nasal Methicillin-Resistant Staphylococcus aureus Carriage Among Orthopedic Patients in Korea

Methicillin-resistant Staphylococcus aureus (MRSA) causes purulent skin and soft tissue infections as well as other life-threatening diseases. Recent guidelines recommend screening for MRSA at the time of admission. However, few studies have been conducted to determine the prevalence and risk factors for MRSA colonization. A prospective data collection and retrospective analysis was performed. MRSA screening tests were performed using nasal swabs in patients enrolled between January 2017 and July 2018. Demographic data, socio-economic data, medical comorbidities, and other risk factors for MRSA carriage were evaluated among 1577 patients enrolled in the study. The prevalence of MRSA nasal carriage was 7.2%. Univariate regression analysis showed that colonization with MRSA at the time of hospital admission was significantly related to patient age, body mass index, smoking, alcohol, trauma, recent antibiotic use, and route of hospital admission. Multiple logistic regression analysis for the risk factors for positive MRSA nasal carriage showed that being under- or overweight, trauma diagnosis, antibiotic use one month prior to admission, and admission through an emergency department were related to MRSA colonization. This study highlights the importance of a preoperative screening test for patients scheduled to undergo surgery involving implant insertion, particularly those at risk for MRSA.

Risk of Surgical Site Infection and Mortality Following Lumbar Fusion Surgery in Patients With Chronic Steroid Usage and Chronic Methicillin-Resistant Staphylococcus aureus Infection

STUDY DESIGN

A retrospective database analysis among Medicare beneficiaries OBJECTIVE.: The aim of this study was to determine the effect of chronic steroid use and chronic methicillin-resistant Staphylococcus aureus (MRSA) infection on rates of surgical site infection (SSI) and mortality in patients 65 years of age and older who were treated with lumbar spine fusion.

SUMMARY OF BACKGROUND DATA

Systemic immunosuppression and infection focus elsewhere in the body are considered risk factors for SSI. Chronic steroid use and previous MRSA infection have been associated with an increased risk of SSI in some surgical procedures, but their impact on the risk of infection and mortality after lumbar fusion surgery has not been studied in detail.

METHODS

The PearlDiver insurance-based database (2005-2012) was queried to identify 360,005 patients over 65 years of age who had undergone lumbar spine fusion. Of these patients, those who had been taking oral glucocorticoids chronically and those with a history of chronic MRSA infection were identified. The rates of SSI and mortality in these two cohorts were compared with an age- and risk-factor matched control cohort and odds ratio (OR) was calculated.

RESULTS

Chronic oral steroid use was associated with a significantly increased risk of 1-year mortality [OR = 2.06, 95% confidence interval (95% CI) 1.13-3.78, P = 0.018] and significantly increased risk of SSI at 90 days (OR = 1.74, 95% CI 1.33-1.92, P < 0.001) and 1 year (OR = 1.88, 95% CI 1.41-2.01, P < 0.001). Chronic MRSA infection was associated with a significantly increased risk of SSI at 90 days (OR = 6.99, 95% CI 5.61-9.91, P < 0.001) and 1 year (OR = 24.0, 95%CI 22.20-28.46, P < 0.001) but did not significantly impact mortality.

CONCLUSION

Patients over 65 years of age who are on chronic oral steroids or have a history of chronic MRSA infection are at a significantly increased risk of SSI following lumbar spine fusion.

LEVEL OF EVIDENCE

3.

Implementation strategies to reduce surgical site infections: A systematic review

BACKGROUND

Surgical site infections (SSIs) portend high patient morbidity and mortality. Although evidence-based clinical interventions can reduce SSIs, they are not reliably delivered in practice, and data are limited on the best approach to improve adherence.

OBJECTIVE

To summarize implementation strategies aimed at improving adherence to evidence-based interventions that reduce SSIs.

DESIGN

Systematic reviewMethods:We searched PubMed, Embase, CINAHL, the Cochrane Library, the WHO Regional databases, AFROLIB, and Africa-Wide for studies published between January 1990 and December 2015. The Effective Practice and Organization Care (EPOC) criteria were used to identify an acceptable-quality study design. We used structured forms to extract data on implementation strategies and grouped them into an implementation model called the "Four Es" framework (ie, engage, educate, execute, and evaluate).

RESULTS

In total, 125 studies met our inclusion criteria, but only 8 studies met the EPOC criteria, which limited our ability to identify best practices. Most studies used multifaceted strategies to improve adherence with evidence-based interventions. Engagement strategies included multidisciplinary work and strong leadership involvement. Education strategies included various approaches to introduce evidence-based practices to clinicians and patients. Execution strategies standardized the interventions into simple tasks to facilitate uptake. Evaluation strategies assessed adherence with evidence-based interventions and patient outcomes, providing feedback of performance to providers.

CONCLUSIONS

Multifaceted implementation strategies represent the most common approach to facilitating the adoption of evidence-based practices. We believe that this summary of implementation strategies complements existing clinical guidelines and may accelerate efforts to reduce SSIs.