MRSA Screening Research Articles

ITS 99 - Quality Initiative to Improve the Electronic Health Record’s Best Practice Advisory for Targeted MRSA Screening Compliance

ITS 99 - Quality Initiative to Improve the Electronic Health Record’s Best Practice Advisory for Targeted MRSA Screening Compliance

Detection of Biofilm Production and Antibiotic Susceptibility Pattern among Clinically Isolated Staphylococcus aureus.

The increasing antibiotic resistance and the ability to form biofilms in medical devices have become the leading cause of severe infections associated with Staphylococcus aureus (S. aureus). Since the bacteria living in biofilms can exhibit 10- to 1,000-fold increase in antibiotic resistance and implicate chronic infectious diseases, the detection of S. aureus ability to form biofilms is of great importance for managing, minimizing, and effectively treating infections caused by it. This study aimed to compare the tube and tissue culture methods to detect biofilm production and antibiotic susceptibility in MRSA and MSSA. The S. aureus isolates were identified by the examination of the colony morphology, Gram staining, and various biochemical tests. Antimicrobial susceptibility testing of all isolates was performed by the modified Kirby-Bauer disc diffusion method as recommended by CLSI guidelines. MRSA screening was performed phenotypically using a cefoxitin disc (30 µg). Isolates were tested for inducible resistance using the D-test, and two phenotypic methods detected biofilm formation. Among 982 nonrepeated clinical specimens, S. aureus was isolated from 103 (10.48%). Among 103 clinical isolates of S. aureus, 54 (52.42%) isolates were MRSA, and 49 (47.57%) were MSSA. Among 54 MRSA isolates, the inducible MLSB phenotype was observed in 23/54 (42.59%) with a positive D-test. By TCP method, 26 (48.1%) MRSA isolates were strong biofilm producers, whereas, among all MSSA isolates, only 6 (12.2%) were strong biofilm producers. MRSA showed strong biofilm production in comparison with MSSA. The TCP method is a recommended reliable method to detect the biofilm among S. aureus isolates, and the TM method could be useful for the screening of biofilm production in S. aureus in the routine clinical laboratory.

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

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. 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. 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. 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.

741. Assessing the Concordance of MRSA Carriage Screening with MRSA Infections

Abstract Background There is a lack of research on MRSA surveillance in children. This study focused on children with confirmed MRSA infections to determine the utility of MRSA screens in guiding empiric anti-MRSA treatment for children without history of MRSA infection. We examined the concordance of screens to assess for differences by infection type, and used statistical analysis to determine significant contributors to concordance. Methods Pediatric hospital patients admitted from 2002-2022 were included. Subjects had MRSA infections subsequent to a MRSA surveillance screen performed in the preceding year. Statistical analysis, namely multivariable and binomial regression, identified associations between MRSA screens and infections. Number needed to treat analysis calculated the utility of re-screening. Results Among 246 subjects, 39.0% had concordant screens. 151 (61.4%) screens were obtained in the two weeks preceding infection. Sensitivity for bacteremia was 50.0% (n=42), for ET/respiratory 44.4% (n=81), for SSTI 29.4% (n=102). For children under 6 months of age, sensitivity was 35.9% (n=78). Multivariable analysis significantly associated days since MRSA screening and decreasing likelihood of concordance. Binomial regression modeled the probability of concordance to drop below 50.0% for all infections after four days, after six days for bacteremia specifically, and twelve days for ET/respiratory infections. Probability of Concordance Over Time The probability of MRSA screening concordance over time based upon binomial prediction modeling. Each line represents the probability of concordance on a given day subsequent to MRSA screening. Number Needed to Treat (test) Analysis A theoretical control arm of patients receiving no re-screening is compared to a theoretical treatment arm receiving re-screening. Each column represents the number needed to re-screen (for a given number of days) to predict one MRSA infection. Absolute risk reduction is overlaid. Conclusion The concordance of screens was far lower than NPV found in past studies. Bacteremia concorded at 50.0%, ET/respiratory infections 44.4%, SSTI 29.4%. The number of days elapsed since MRSA screening proved the only significant covariate. When that covariate modeled the probability of screening concordance with infection, 7 days represented when the probability of concordance fell to or dropped below 50.0% for infection types. Only patients with a known MRSA infection were included in our study, and concordance of screens was far lower than NPV found in past studies; previous results may have been impacted by low prevalence to inform high NPV. We suggest that negative MRSA screens should not invalidate reasonable suspicion for MRSA infection in patients with high pre-test probabilities for infection. Re-screening patients may optimize concordance. Disclosures All Authors: No reported disclosures

1266. Refining Antimicrobial Stewardship by De-escalating Vancomycin Using MRSA (Methicillin Resistant Staphylococcus aureus) Nasal Screening in a Community Hospital Setting

Abstract Background Our institution has prioritized appropriate use of anti-Methicillin-resistant Staphylococcus aureus (MRSA) drugs such as vancomycin. The overuse of anti-MRSA drugs contributes to drug toxicities and development of resistant organisms such as vancomycin-resistant enterococcus (VRE). Recent studies show that MRSA nasal surveillance screening has a high negative predictive value of 96.5% in all types of pneumonia. At our community hospital a decentralized pharmacist-driven MRSA nares screening protocol was novel. We report the results of implementing a MRSA nares screening protocol for vancomycin de-escalation in pneumonia patients. Methods A decentralized pharmacist reviewed patients with a diagnosis of pneumonia and prescribed vancomycin. The pharmacist ensured that a culture-based MRSA nares screen was performed within 48 hours of admission, if not already ordered. If the nares screen returned negative and respiratory cultures did not grow MRSA at 48 hours, the decentralized pharmacist contacted the medical team to recommend discontinuing vancomycin. Reasons for exclusion included a positive respiratory culture for MRSA within the prior 7 days, septic shock, alternative site of MRSA infection, and greater than 48 hours of anti-MRSA therapy at time of swab collection. Results 164 patients were reviewed by pharmacy between 6/16/22 and 4/25/23. 98% of MRSA nares screening had been performed within 48 hours of admission. MRSA screen was ordered by the decentralized pharmacist in 44% of patients. 89% of patients screened were negative for MRSA and reviewed for de-escalation of vancomycin. In 40% of patients, vancomycin was discontinued after recommendations by the decentralized pharmacist, with 95% of the recommendations accepted by the primary hospitalist physician. 37% of patients' vancomycin was discontinued by the attending physician. Overall, 77% of patients with negative MRSA nasal screen results were successfully de-escalated. Conclusion Our data highlights the effectiveness of close physician-pharmacy collaboration. Most nares cultures were negative for MRSA allowing for de-escalation of antibiotics. Pharmacist recommendations were accepted majority of the time. Given the data, we plan to apply this approach for other ongoing stewardship initiatives. Disclosures All Authors: No reported disclosures

Immunoinformatics design of B-cell multi-epitope peptide for the diagnosis of Methicillin Resistant Staphylococcus aureus (MRSA) infection

Background: Methicillin (oxacillin)-resistant Staphylococcus aureus (MRSA) remains a significant clinical and epidemiological pathogen in hospital settings and in the community world-wide. The resistance to methicillin in Staphylococcus aureus is mediated by the mecA gene, which encodes penicillin-binding protein 2a (PBP2A). Rapid patient screening for MRSA is essential for infection control procedures in order to possibly enhance the outcomes of infected patients. In this study, we utilized PBP2A to predict and create a novel synthetic protein with multiple immunodominant B cell epitopes for rapid diagnosis of MRSA using an in-silico approach. Methods: Seven putative PBP2A peptides were used to analyze the protein’s primary, secondary, and tertiary structures (BepiPred). The B cell construct was then evaluated using I-TASSER server, and physicochemical properties, and homology modeling of the 3 D structure of the protein were obtained. Results: In silico analyses revealed regions with high immunogenicity. Altogether, 19 consented epitopes were selected for the in-silico succession; three consented epitopes from ALJ10988.1, three from ORN56903.1, three from AFJ06714.1, one from AEO00772.1, three from WP_000721309.1, three from WP_057521704.1, and three from WP_063851348.1. The constructs have an average length of 503 amino acids, molecular weight of 55,151.78, instability index of 41.44, theoretical PI of 9.28 and a C score −1.50. In addition, the parameters that were examined indicated the newly multi-epitope construct could potentially serve as a theoretical framework for the development of a MRSA diagnostic kit. Conclusions: Overall, we have developed an antigen-based multi-epitope peptide for the rapid and accurate diagnosis of MRSA infection through an in-silico approach, acceptable in terms of antigenicity, physicochemical properties, structural stability and strong immunogenicity.

916. Increased efficiency and impact of implementing ILUM insight within an antimicrobial stewardship program (ASP) at an academic medical center

Abstract Background An ASP is mandated for all hospitals and requires extensive resources with multidisciplinary collaboration. We measured the impact of implementing real-time decision support software (ILUM Insight) within our ASP. Methods Our ASP has relied on prior authorization since 2002 and focused audit and feedback since 2015. In August 2021 we implemented to bring actionable data to front-line stewards. ILUM provides real-time notifications, organizes communications, and tracks patient-and provider-level data. We hypothesized that ILUM would increase the efficiency of ASP workflow and result in decreased antimicrobial utilization. We compared data 6 months before (8/20 – 1/21) and after (8/21 – 1/22) implementation. There were no significant staffing changes during either period. Results Existing notifications within ILUM were tailored to local practices, including alerts with intervention for positive blood cultures, antibiotic de-escalation, and bug-drug mismatches. New notifications were built for restricted antimicrobials, antibiotic timeouts, and MRSA screening. ASP pharmacists and physicians received training in July and November, respectively. A breakdown of all notifications received during the post-implementation period is provided in Fig 1. With increased ILUM usage, the number of interventions made by our ASP increased while missed opportunities decreased (Fig 2.). During the same time period, ASP communications rose from 205 to 1200 per month. Comparing pre- and post-implementation periods, antimicrobial days of therapy (DOT) per 1,000 patient days (PD) decreased by 14.5% from a median of 969 to 846 per month (Fig 3;P=0.002). Antimicrobial expenditures were decreased by a median 21% per month during the post-intervention period compared to baseline. Among patients prescribed antimicrobials during an index admission, 30-day re-admissions decreased from 330 to 262 and re-admissions associated with re-ordering of antimicrobials decreased from 235 to 182 (Fig 4). Conclusion Custom-designed, task-specific software improves the efficiency of daily ASP workflow and significantly decreased antimicrobial utilization without the need for additional ASP team members. Disclosures Ryan K. Shields, PharmD, MS, Infectious Disease Connect: Advisor/Consultant|Merck: Advisor/Consultant|Merck: Grant/Research Support|Roche: Grant/Research Support J Ryan Bariola, MD, Infectious Disease Connect: Salary support|Merck: Grant/Research Support Caley Yakemowicz, n/a, Infectious Disease Connect: Employee Courtney Simonick, n/a, Infectious Disease Connect: Stocks/Bonds Riaan Erwee, na, Infectious Disease Connect: Employee Erin K. McCreary, PharmD, Infectious Disease Connect: Advisor/Consultant Rima Abdel-Massih, MD, Infectious Disease Connect: Co founder and Chief Medical Officer|Infectious Disease Connect: Ownership Interest.

2172. Closing the CAP Gap: Improving the Management of Community Acquired Pneumonia (CAP)

Abstract Background In October 2019 updated community acquired pneumonia (CAP) guidelines were published, highlighting indications for empiric anti-MRSA and antipseudomonal antibiotics and use of MRSA nares screens. During a review of patients receiving vancomycin and piperacillin-tazobactam at our institution in 2020 we noted frequent use of anti-MRSA and antipseudomonal antibiotics and infrequent use of MRSA nares screens for CAP. In May 2020 we initiated a multifaceted intervention, including prospective audit and feedback, an updated pneumonia order set, and system-wide education. In this study we sought to describe gaps in the care of patients with CAP at our institution and to evaluate the impact of a multifaceted intervention on those gaps in care. Methods We performed a retrospective cohort study on a random sample of unique adult patients admitted with pneumonia from January 1, 2020 through June 30, 2021. Exclusion criteria included COVID infection within 4 weeks of admission, no antibiotics for pneumonia given during admission, immunocompromised condition, and diagnosis of hospital-acquired or ventilator-associated pneumonia. The primary objective was to describe the percentage of patients receiving appropriate anti-MRSA and antipseudomonal therapy and MRSA nares testing during the study period. The secondary objective was to compare appropriateness of these outcomes before and after the intervention. Study groups Results For the 126 patients reviewed, 68.3% received the appropriate empiric spectrum of activity for MRSA and Pseudomonas aeruginosa, improving from 60% to 80% before and after the intervention respectively. The percentage of patients screened for MRSA increased from 6 to 34%; however, the percentage of appropriate MRSA screens decreased from 71 to 54% because screens were often collected despite absence of MRSA risk factors. Results Conclusion The percentage of patients receiving appropriate anti-MRSA and antipseudomonal therapy for CAP improved after a multifaceted stewardship intervention. The percentage of patients for whom appropriate MRSA nares screens was performed worsened, mainly due to use of MRSA nares screens when not needed. Disclosures All Authors: No reported disclosures.

Survey regarding prevention of surgical site infection after orthopaedic surgery in Belgium: are we on the right track?

Prevention strategies are essential to reduce the rate of surgical site infection (SSI) in orthopaedic surgery. Members of the Royal Belgian Society for Orthopaedic Surgery and Traumatology (SORBCOT) and the Belgische Vereniging voor Orthopedie en Traumatologie (BVOT) were asked to answer a 28-question questionnaire on the internet about the application of surgical antimicrobial prophylaxis measures and to compare them with current inter- national recommendations. 228 practicing orthopedic surgeons responded to the survey from different regions (Flanders, Wallonia and Brussels), different hospitals (university, public and private), different levels of experience (< 5 years, 5 to 10 years and > 10 years) and different subspecialties (lower limb, upper limb and spine). Regarding the questionnaire: 7% systematically perform a dental check-up. 47.8% of the participants never carry out a urinalysis, 41.7% when the patient presents symptoms and 10.5% carry it out systematically. 2.6% systematically propose a pre-operative nutritional assessment. 5.3% of respondents suggest stopping biotherapies (Remicade®, Humira®, rituximab®, etc.) before an operation and 43.9% do not feel comfortable with this type of treatment. 47.1% suggest smoking cessation before the operation and 22% of them advise smoking cessation for a period of 4 weeks. 54.8% never carry out MRSA screening. 68.3% systematically per- formed hair removal, 18.5% when the patient had hirsutism. Among them, 17.7% use shaving with razors. Alcoholic Isobetadine is the most used product with 69.3% when disinfecting the surgical site. 42.1% of the surgeons chose a delay between the injection of antibiotic prophylaxis and the incision of less than 30 minutes, 55.7% between 30 and 60 minutes and 2.2% between 60 and 120 minutes. However, 44.7% did not wait for the injection time to be respected before incising. An incise drape is used in 79.8% of cases. The response rate was not influenced by the surgeon's experience. Most international recommendations in terms of prevention of surgical site infection are correctly applied. However, some bad habits are maintained. These include the use of shaving for depilation and the use of non-impregnated adhesive drapes. Practices that could be improved include management of treatment in patients with rheumatic diseases, a 4-week smoking cessation period, and treating positive urine tests only when symptomatic.

A CASE OF BORDETELLA BRONCHISEPTICA AND PNEUMOCYSTIS JIROVECI PNEUMONIA IN A YOUNG PATIENT

A CASE OF BORDETELLA BRONCHISEPTICA AND PNEUMOCYSTIS JIROVECI PNEUMONIA IN A YOUNG PATIENT

Diagnostic Accuracy of CHROMagar MRSA for Detection of Methicillin-Resistant Staphylococcus Aureus (MRSA) from Screening Swab Specimens

Objective: To determine the diagnostic accuracy of CHROMagar MRSA for detecting MRSA from screening swab specimens keeping the Cefoxitin disk diffusion test as the reference method.&#x0D; Study Design: A cross-sectional validation study.&#x0D; Place and duration of study: Department of Microbiology, Armed Forces Institute of Pathology (AFIP), Rawalpindi Pakistan, from Mar to Aug 2019.&#x0D; Methodology: A total of 243 screening swab specimens, e.g., axillary, nasal and web swabs, each of hospitalized patients and healthcare workers (HCW) submitted for MRSA screening were included in the study and were processed simultaneously on blood agar, MacConkey agar and CHROMagar MRSA. The agar plates were incubated at 35°C ± 2°C for 18-24 hours in ambient air. The cefoxitin disk diffusion test followed the isolation and identification of MRSA according to the latest Clinical and Laboratory Standards Institute (CLSI) guidelines. In CHROMagar MRSA screening, after incubation, plates were examined for the presence of mauve colonies (MRSA detected), and the results were obtained and validated against the reference method of Cefoxitin disk diffusion.&#x0D; Results: Overall, the diagnostic accuracy of CHROMagar MRSA for detecting MRSA was 97.53%. Diagnostic accuracy of CHROMagar MRSA was 95.1%, 97.5% and 100% in axillary, nasal and web specimens, respectively. The rate of MRSA detection was maximum in axillary swabs, i.e., 40.7%, followed by 29.6% and 9.8% in nasal and web swabs, respectively.&#x0D; Conclusion: CHROMagar MRSA is found to be accurate for the detection of MRSA. It is reliable, easy to perform, less timeconsuming, and cost-effective. It is an affordable alternative to the conventional..............

Characterization of Methicillin-resistant Staphylococcus aureus From Children at Hospital Admission: Experiences From a Hospital in a German Metropolitan Area.

Since the 1990s, community-associated Methicillin-resistant Staphylococcus aureus (CA-MRSA) are described as emerging independent of health care. CA-MRSA is associated with the colonization and infection of healthy, immunocompetent younger individuals. While skin and soft tissue infections (SSTI) are predominant, life-threatening syndromes can also occur. In this retrospective study, we investigated MRSA stains isolated from community-onset infections and from MRSA screening of children at admission to a tertiary-care hospital in 2012-2018. In total, 102 isolates were subjected to antibiotic susceptibility testing by broth microdilution, spa -typing, multilocus sequence typing, SCC mec typing and virulence/resistance gene detection by polymerase chain reaction. The majority of isolates originated from community-onset infections (80/102), of these primarily from SSTI (70/80). Additional strains were isolated by MRSA screening (22/102). In total 61.8% of the MRSA carried the gene for the Panton-Valentine leukocidin ( lukPV ). Molecular characterization of isolates revealed various epidemic MRSA clones, circulating in both community and hospital settings. Most prevalent epidemic lineages were isolates of the "European CA-MRSA clone" (CC80-MRSA-IV), the "Bengal Bay clone" (ST772-MRSA-V), or the "USA300 NAE clone" (ST8-MRSA-IVa). Our data highlight the importance of CA-MRSA causing SSTI in children. More frequent microbiological and molecular analysis of these strains is important for targeted treatment and can provide valuable data for molecular surveillance of the pathogen.

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

To assess the incidence of MRSA positive patients in pregnancy, as well as the postpartum outcomes in MRSA positive patients. 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 35-37weeks 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. The incidence of MRSA during the 4year 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. 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.

The use of behaviour change theory for infection prevention and control practices in healthcare settings: A scoping review.

BackgroundInfection prevention and control (IPC) practices performed by healthcare workers are key to the prevention and management of infections. Compliance with IPC practices is often low, they are therefore commonly the focus of improvement interventions. Designing interventions that are based on behaviour change theories may help to improve compliance to practice. The aim of this review is to synthesise the evidence on the application of behaviour change theories to interventions to improve IPC practice in healthcare settings.MethodsA scoping review was conducted following the Joanna Briggs Institute methodological framework. The theories of focus were the Theoretical Domains Framework (TDF), Capability, Opportunity, Motivation, Behaviour (COM-B) and Behaviour Change Wheel (BCW). Studies which applied these theories to any IPC practice were included.ResultsEleven studies were identified which met the inclusion criteria. The IPC behaviours investigated were hand hygiene (7), antimicrobial stewardship (3), and MRSA screening (1). Nine studies explored barriers and facilitators to existing IPC practice; three used their findings to design a behaviour change intervention or tool. Domains of ‘beliefs about consequences’, ‘environmental context/resources’, and ‘social/professional role and identity’ were identified as key across all three IPC behaviours.DiscussionThis review has demonstrated the use of behavioural theories to understand determinants of behaviour related to IPC practice. Currently, there are few published examples of interventions to improve IPC practice that have been underpinned by behavioural theory. Practitioners in IPC should consider the use of these methods to enhance the efficacy of strategies to change healthcare worker behaviour.

Impact of methicillin‐resistant Staphylococcus aureus polymerase chain reaction nasal swabs on vancomycin utilisation in patients admitted to the intensive care unit with respiratory infections

AbstractBackgroundMethicillin‐resistant Staphylococcus aureus (MRSA) nasal polymerase chain reaction (PCR) screening has a negative predictive value as high as 96% for pneumonia. Using nasal PCR, care providers can detect the presence or absence of MRSA earlier and potentially decrease the duration of vancomycin therapy in patients with negative results.AimsThe primary objective was to assess the impact of MRSA nasal PCR on vancomycin length of therapy in patients admitted to the intensive care unit (ICU) with respiratory infections.MethodsThis was a retrospective, quasi‐experimental, uncontrolled before—after study, comparing patients receiving screening versus those who did not. Patients over the age of 18, admitted to ICU with respiratory infections who received at least one dose of vancomycin were included in this study. This investigation received exemption from the South Nassau Communities Hospital and Western Institutional Review Board (reference number SNCH‐E14) and was conducted in accordance with the tenets espoused in the Declaration of Helsinki.ResultsA total of 77 patients, 22 in the study group and 55 in the comparator group were included in the analysis. There was a reduction in median length of vancomycin therapy in the MRSA PCR group compared to the unscreened group (1.7 days vs. 6 days, IQR: 4.15 vs. 4.8, p &lt; 0.001). There was a reduction in median vancomycin levels performed (3 levels vs. 1 level, p = 0.619).ConclusionsThe use of nasal PCR screening for MRSA was associated with a reduction in median vancomycin length of therapy for patients admitted to the ICU with respiratory infections.

Clinical Utility of Dual Anterior Nares and Oropharynx MRSA Screening PCR for Patients with Suspected Pneumonia.

We reviewed the electronic health records of 1,419 inpatients with anterior nares (AN) and oropharynx (OP) MRSA PCR tests. Concordance was 96.5%. In discordant cases, AN negative-OP positive results increased detection of probable MRSA pneumonia by only 0.3%. A dual testing approach has limited utility in detecting MRSA pneumonia and increases resource utilization.

Abstract 17057: Tropheryma Whipplei Endocarditis: A Diagnosis In Hindsight

Description of case: We report a case of Tropheryma whipplei endocarditis, a rare cause of blood-culture-negative infective endocarditis (BCNIE). Due to its rarity and lack of availability of diagnostic tests in district hospitals, the diagnosis remains challenging. The objective of this case report is to increase physician awareness of this pathogen. A 61-year-old man presented to the Emergency Department with central chest pain at rest. A 12-lead ECG demonstrated ST- segment depression in V4-V6 leads, and his serial troponin levels were raised. He was commenced on treatment for acute coronary syndrome and transferred to the Coronary Care Unit. An echocardiogram showed a 15mm x 15mm vegetation in the aortic valve with mild aortic regurgitation. His initial microbiology workup, which included two sets of blood cultures (pre-antibiotics), MRSA screen &amp; COVID-19 PCR, was negative. He was transferred to a cardiothoracic centre four days later. Pre-operative CT coronary angiogram showed severe three vessel coronary artery disease. He underwent triple coronary artery by-pass grafts and tissue aortic valve replacement. During early post-op recovery, he had fever episodes and an elevated C-reactive protein of 280 mg/L but normal white cell counts. He was treated with intravenous Tazocin for hospital-acquired pneumonia and discharged on doxycycline. Two weeks post-discharge, he had a positive 16S/18S PCR for Tropheryma whipplei on molecular analysis of the aortic valve. He was treated for Whipples endocarditis with a 4-week course of IV Ceftriaxone, followed by a 12-month course of oral Cotrimoxazole. The patient has reported doing well since the surgery. Discussion: Molecular assay with PCR of the heart valve is the mainstay of diagnosing Whipple’s endocarditis. There have been 5 previously reported cases of Whipple’s endocarditis in the United Kingdom in our knowledge. It is likely under-reported because of a reliance on tissue diagnosis. Preceding intestinal manifestations and arthralgia should raise its clinical suspicion for timely workup. Physician awareness of Whipple’s Endocarditis is paramount in investigating for this pathogen.

Screening of MRSA colonization in patients undergoing total joint arthroplasty.

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. 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. 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. 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. IV.

Utility of methicillin-resistant Staphylococcus aureus (MRSA) nasal screening in patients with acute myeloid leukemia (AML).

Current literature has demonstrated the utility of the MRSA nasal screen as a de-escalation tool to decrease unnecessary anti-MRSA antibiotic therapy. However, data on the applicability of this test in patients with hematologic malignancy is lacking. This is a single-center, retrospective cohort study of patients with acute myeloid leukemia (AML) with or without a history of hematopoietic cell transplant (HCT), with pneumonia and MRSA nasal screening with respiratory cultures obtained. The primary outcome was to determine the negative predictive value (NPV) of the MRSA nasal screen for MRSA pneumonia. Secondary outcomes included sensitivity, specificity, positive predictive value (PPV) of the MRSA nasal screen and prevalence of MRSA pneumonia. Of 98 patients with AML and pneumonia, the prevalence of MRSA pneumonia was 4.1% with confirmed positive MRSA respiratory cultures observed in 4 patient cases. In patients with confirmed MRSA pneumonia, 3 had positive MRSA nasal screens while 1 had a false negative result, possibly due to a long lag time (21days) between MRSA nasal screen and pneumonia diagnosis. Overall, the MRSA nasal screen demonstrated 75% sensitivity and 100% specificity, with a PPV of 100% and a NPV of 98.9%. Given the low prevalence, empiric use of anti-MRSA therapy in those AML and HCT patients with pneumonia may not be warranted in clinically stable patients. For patients in whom empiric anti-MRSA antibiotics are initiated, nasal screening for MRSA may be utilized to de-escalate anti-MRSA antibiotics in patients with AML with or without HCT.

Current practices and evaluation of barriers and facilitators to surgical site infection prevention measures in Jimma, Ethiopia.

Surgical site infections (SSIs) greatly burden healthcare systems around the world, particularly in low- and middle-income countries. We sought to employ the Systems Engineering Initiative for Patient Safety (SEIPS) model to better characterize SSI prevention practices and factors affecting adherence to prevention guidelines at Jimma University Medical Center (JUMC). Our cross-sectional study consisted of semistructured interviews designed to elicit perceptions of and barriers and facilitators to SSI prevention among surgical staff and observations of current preoperative, perioperative, and postoperative SSI prevention practices in surgical cases. Interviews were recorded, manually transcribed, and thematically coded within the SEIPS framework. Trained observers recorded compliance with the World Health Organization's SSI prevention recommendations. A tertiary-care hospital in Jimma, Ethiopia. Surgical nurses, surgeons, and anesthetists at JUMC. Within 16 individual and group interviews, participants cited multiple barriers to SSI prevention including shortages of water and antiseptic materials, lack of clear SSI guidelines and training, minimal Infection Prevention Control (IPC) interaction with surgical staff, and poor SSI tracking. Observations from nineteen surgical cases revealed high compliance with antibiotic prophylaxis (94.7%), hand scrubbing (100%), sterile gloves and instrument use (100%), incision site sterilization (100%), and use of surgical safety checklist (94.7%) but lower compliance with preoperative bathing (26.3%), MRSA screening (0%), and pre- and postoperative glucose (0%, 10.5%) and temperature (57.9%, 47.3%) monitoring. Utilizing the SEIPS model helped identify institution-specific barriers and facilitators that can inform targeted interventions to increase compliance with currently underperformed SSI prevention practices at JUMC.