Nasal Screening Research Articles

Impact of Methicillin-Resistant Staphylococcus aureus Nasal Polymerase Chain Reaction Screening Tests on Duration of Vancomycin Therapy for Skin and Soft Tissue Infections.

Background: Recent literature demonstrated a 24-hour reduction in vancomycin duration of therapy (DOT) for skin and soft tissue infections (SSTIs) with a negative methicillin-resistant staphylococcus aureus (MRSA) nasal screening versus a positive nasal screening. Objective of this study was to investigate vancomycin DOT in patients with SSTIs who received MRSA nasal polymerase chain reaction (PCR) screening versus those who did not receive MRSA nasal PCR screening. Methods: A retrospective, multi-center, cohort study was completed in admitted adult patients on vancomycin for SSTI from 01/01/2020 to 09/30/2022. Hospital policy permits any clinician to order a MRSA nasal PCR screening test for various indications, including SSTIs, pneumonia and sepsis. Results: One-hundred-fifty-one patients were included, of which 71 had MRSA nasal PCR screening tests obtained, and 80 did not. The median vancomycin DOT in patients with MRSA nasal PCR screening tests was 19.9 versus 36.7 hours (P = .014) in patients without screening tests. Conclusion: Patients with SSTIs who receive MRSA nasal PCR screening tests have a shortened vancomycin DOT. These results contribute to current data in support of the efficacy and clinical utility of obtaining MRSA nasal PCR screening tests for SSTIs.

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

BackgroundNasal 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.MethodsA 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.ResultsA 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).ConclusionsDespite the low number of SSI, nasal screening and targeted decolonisation of S. aureus were associated with a reduction in S. aureus SSI.

#2355 Eradication of Staphylococcus aureus carriage in patients undergoing peritoneal dialysis

Abstract Background and Aims Peritonitis is a common and serious complication of peritoneal dialysis (PD). A single episode of severe peritonitis or multiple peritonitis episodes frequently leads to diminished peritoneal ultrafiltration capacity, hospitalization, and a switch to hemodialysis. Prevention of infection is the mainstay for the reduction of peritonitis rate. According to the current guidelines, we use nasal antibiotic prophylaxis if patients are identified as nasal Staphylococcus aureus carriers on screening prior to PD beginning. Eradication of S. aureus Regular with nasal mupirocin reduces the rate of exit-site infections but has uncertain effects on the risk of peritonitis. The aim of this study was to evaluate the rate of S. aureus peritonitis in our cohort of patients receiving PD. Method A retrospective single-center study was conducted in a large Italian PD center. We reviewed all cases of bacterial peritonitis from 1999 to 2023. Demographic and clinical characteristics of the patients and microbiological features of the bacteria identified in cultures were extracted from electronic health record. From 2011, all patients were screened before surgery for Methicillin-resistant S. aureus (MRSA) and methicillin-sensitive S. aureus (MSSA) with nares swabs. All patients with positive nasal colonization for MSSA and MRSA were treated with nasal mupirocin (nasal ointment twice daily for 5 consecutive days every 4 weeks) until eradication was confirmed by a nasal swab. According to our protocol, from 2011, screening for S. aureus carriage along peritoneal fluid culture was performed in all patients on PD with an episode of peritonitis to verify nasal colonization with S. aureus. The study was approved by the regional ethical committee of Emilia Romagna (507/2021/OSS/AOUMO SIRER ID 2845). Results Overall, 345 cases of peritonitis were reviewed in 214 patients who received peritoneal dialysis. In our center, the rate of peritonitis was 0.23 episodes/patient-year. After the introduction of nasal screening for S. aureus carriage, the episodes of S. aureus peritonitis decreased in frequency (0.0093 episodes/patient-year vs. 0.034 episodes/patient-year) and as absolute number (17.8% vs 3.6%; p = 0.001). No differences were observed in the rate of catheter removal in the two populations (p = 0.99). The age of 109 patients screened for S. aureus carriage was 64.1 ± 17 years. Males accounted for 58.9% and automated PD (APD) was chosen by 66% of the subjects. After an average period of 1.6 years from the start of PD, 7 patients experienced S. aureus peritonitis in the absence of exit-site or tunnel catheter infection. Nasal screening at the time of peritonitis showed that half of them were carriers of S. aureus and half were negative (one patient was not screened). Colonization from S. aureus was found in another 9 patients whose peritonitis was caused by a different type of bacteria (44% S. epidermidis, 33.3% Enterobacteriaceae, 11.1% Acinetobacter, and 11.1% culture-negative peritonitis). Conclusion Our data document that screening for S. aureus, along with other preventive measures, contributes to significantly reducing the rate of S. aureus peritonitis in patients screened and treated for S. aureus carriage at the time of PD start. Routine screening and the use of a mask during connection are required because recolonization occurs frequently in this population.

Addition of vancomycin to cefazolin is often unnecessary for preoperative antibiotic prophylaxis during total joint arthroplasties

PurposeThe gold standard to decrease total joint arthroplasty (TJA) periprosthetic joint infection (PJI) is preoperative antibiotic prophylaxis. Despite substantial prevention efforts, rates of PJIs are increasing. While cefazolin is the drug of choice for preoperative prophylaxis, adjunctive vancomycin therapy has been used in methicillin-resistant Staphylococcus aureus (MRSA) endemic areas. However, studies examining these combinations are lacking. Therefore, we sought to examine complications among vancomycin plus cefazolin and cefazolin-only recipients prior to primary TJA in a single institutional sample and specifically assessed: (1) microbiological aspects, including periprosthetic joint and surgical site infections, microbes cultured from the infection, and frequency of microbes cultured from nasal swab screening; (2) 30-day emergency department (ED) visits and re-admissions; as well as (3) associated risk factors for infection.MethodsA total of 2,907 patients (1,437 receiving both cefazolin and vancomycin and 1,470 given cefazolin only) who underwent primary TJA between 1 January 2014 and 31 May 2021 were identified. SSI and PJI as well as rates of cultured microbes rates were obtained through one year, those with prior nasal swab screening and 30-day re-admission were identified. Subsequently, multiple regression analyses were performed to investigate potential independent risk factors for PJIs.ResultsThere was no significant difference in the rates of SSI (P = 0.089) and PJI (P = 0.279) between the groups at one year after operation. Commonly identified organisms included Staphylococcus and Streptococcus species. The VC cohort did have a greater reduction of MRSA in the previously nasal swab-screened subset of patients. Multiple regression analyses demonstrated emergency as well as inpatient admissions as risk factors for PJI.ConclusionsAdjunctive vancomycin therapy offers increased protection against MRSA in previously screened individuals. However, those negative for MRSA screening do not require vancomycin and have similar protection to infection compared to recipients of cefazolin only in a high-powered single institution analysis in an MRSA endemic area.

Antimicrobial resistance profile of Staphylococcus aureus isolated from patients, healthcare workers, and the environment in a tertiary hospital in Addis Ababa, Ethiopia.

Staphylococcus aureus infection and colonization in patients may be transmitted to healthcare providers and the environment and subsequently cause healthcare-associated infections in other patients. Pathogenic S. aureus strains produce virulence factors, such as Panton-Valentine Leukocidin (PVL), that contribute to the severity of infections and aid in their spread. The emergence of antimicrobial resistance (AMR) is additional concern with respect to S. aureus infection. In this study, the virulence genes and antibiotic resistance profiles of S. aureus were characterized from patients' clinical isolates, healthcare workers' (HCWs') nasal colonization screenings, and the environment at a tertiary healthcare hospital in Addis Ababa, Ethiopia. A total of 365 samples were collected from September 2021 to September 2022: 73 patients' clinical specimens, 202 colonization screenings from HCWs, and 90 hospital environment's swabs. Fifty-one (25.2%) HCW and 10/90 (11.1%) environment S. aureus isolates were identified. Among the 134 isolates, 10 (7.5%) were methicillin-resistant S. aureus (MRSA). Three (4.1%), five (9.8%), and two (20.0%) of the MRSA isolates were identified from the patients, HCWs, and the environment, respectively. Overall, 118 (88.1%) were ampicillin and penicillin resistant; 70 (52.2%) were trimethoprim sulfamethoxazole resistant; and 28 (20.9%) were erythromycin resistant. S. aureus isolates from patients were more resistant to antibiotics than isolates from HCWs or the hospital environment (p<0.05). A total of 92/134 (68.6%) isolates possessed the lukfF-PV gene, which was identified in 62 (85.0%), 26 (51.0%), and 4 (40.0%) of the patient, HCWs, and the environment, respectively. The proportion of lukfF-PV gene containing S. aureus isolated from patient samples was statistically significant. Four (40.0%) of the MRSA isolates also had the lukfF-PV gene. The identification of highly AMR and virulence factors from patients, HCWs and the environment is concerning. Further studies are needed to identify potential transmission links and improve infection prevention and control.

Efficacy evaluation of upper gastrointestinal endoscopy screening for secondary prevention of gastric cancer using the standardized detection ratio during a medical check-up in Japan.

We used standardized detection ratio to evaluate the quality of nasal upper gastrointestinal endoscopy screening for the secondary prevention of gastric cancer, and examined the gastric cancer risk in the era of total Helicobacter pylori (H. pylori) eradication. We performed 21,931 upper gastrointestinal endoscopies, 77 subjects were diagnosed with gastric cancer. Of these, 28 had gastric cancer after H. pylori eradication, 47 had gastric cancer with H. pylori-positive or others, and 2 had H. pylori-negative gastric cancer. The Standardized detection ratios for men and women were 5.33 and 4.82, respectively. Multivariable logistic regression analyses performed exclusively on first endoscopy subjects, excluding H. pylori-negative gastric cancer, revealed that smoking was a risk factor for developing gastric cancer (adjusted odds ratio, 3.31; 95% confidence interval, 1.65-6.64; p = 0.001). A statistically significant interaction was found between daily alcohol consumpption and H. pylori eradication on gastric cancer development (p = 0.005). In conclusion, relatively high standardized detection ratio values suggest that an appropriate endoscopic diagnosis of gastric cancer should be performed during a medical check-up. Smoking is a risk factor for developing gastric cancer, and continued alcohol consumption suggests a possible risk for developing gastric cancer after H. pylori eradication.

Evaluation of methicillin-resistant Staphylococcus aureus nasal swab screening at a large comprehensive cancer center.

The aim of this study is to determine the predictive values of MRSA swab screenings in patients with cancer. This is a retrospective cohort observational study of adult patients admitted to The University of Texas MD Anderson Cancer Center between January 2019 and October 2022. Data collected from patients with documented MRSA nasal swab screenings and clinical cultures taken within 7 days were collected. The first documented MRSA swab screening and culture results from unique patients were included for analysis to calculate sensitivity, specificity, positive predictive value, and NPV. A total of 6475 patients with MRSA nasal swab cultures had 13129 clinical cultures from different anatomical sites. Of the patients included, 57% had a solid tumor and 37% had a hematological malignancy, with 82% of patients receiving an anti-MRSA antibiotic prior to MRSA nasal swab. There were 167 documented positive MRSA cultures, most commonly from a wound (41.3%) or respiratory source (24%). Overall sensitivity and specificity for all culture sites were 50.9% and 98.4%, respectively, with an overall NPV of 99.4%. The NPV was 99.8% for bloodstream infections, 98.5% for respiratory infections, 92.6% for wound infections, and greater than 99% for other culture sites. The specificity and negative predictive value of MRSA swab screenings in patients with cancer was high overall and consistent with the literature in immunocompetent patients. These results may aid in antimicrobial stewardship activities that can help guide the discontinuation of empiric antibiotics in patients with cancer.

Estimating effectiveness of nasal decolonization in prevention of peri-prosthetic joint infection in nasal carriers of Staphylococcus aureus undergoing arthroplasty in a tertiary care institution

Introduction: Peri-prosthetic joint infection (PJI) is one of the most challenging complications after total joint arthroplasty (TJA) surgeries. This study aims to (i) compare overall PJI rates with and without pre-operative nasal screening and decolonization for Staphylococcus aureus; (ii) estimate the difference in SSI rates between carriers and non-carriers undergoing TJA; and (iii) determine the efficacy of decolonization in reducing PJI rate in nasal carriers. Methods: A total of 760 patients were included in the study; with 399 patients in the study group, who underwent pre-operative screening and decolonization for nasal colonization with S. aureus; and 361 patients in the control group, who did not undergo pre-operative screening for nasal colonization. Patients were followed for 90 days post-surgery, and PJI rates were recorded following the Centers for Disease Control SSI criteria. Results: Twenty-one (5.26%) out of 399 patients in the study group developed PJI as opposed to 38 (10.53%) out of 361 patients in the control group. PJI rate due to either MSSA or MRSA was 2.5% in the study group (10/399) as opposed to 7.75% in the control group (28/361), with “P value” of 0.002 (&lt;0.05). Discussion: The overall SSI incidence was reduced by 51% after implementing the decolonization protocol. Regarding specific S. aureus SSI, 7.5% of the SSIs in the control group were caused by S. aureus, while only 2.5% were caused by this microorganism after implementing the screening and decolonization protocol. Conclusion: Implementing a screening and decolonization protocol for S. aureus before TJA can lead to a significant reduction in S. aureus surgical site infections.

Nasal Screening of Health Care Workers (Nursing staff) to Study the Prevalence of Methicillin Resistant Staphylococcus Aureus (MRSA) Carriage and its Antibiotic Sensitivity Profile in a Rural Tertiary Health Care Center

Nasal Screening of Health Care Workers (Nursing staff) to Study the Prevalence of Methicillin Resistant Staphylococcus Aureus (MRSA) Carriage and its Antibiotic Sensitivity Profile in a Rural Tertiary Health Care Center

MRSA nasal screening predictive values assessment in patients with osteomyelitis.

The purpose of this study was to evaluate the diagnostic value of methicillin-resistant Staphylococcus aureus (MRSA) nasal screening utilizing polymerase chain reaction (PCR) assays in patients with osteomyelitis. A multisite, retrospective adult chart review from March 2021 to June 2022 was conducted, with no interventions performed. Patients treated with anti-MRSA therapy for osteomyelitis, MRSA nares PCR collected within 48 hours of antibiotic initiation, and related cultures were evaluated. Adults with associated cultures were assessed for concordance with MRSA nares PCR screening results. The primary outcome was the diagnostic value of MRSA nares PCR assay screening for predicting MRSA osteomyelitis. An assessment of sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) was performed. Key secondary outcomes included length of hospital stay and duration of anti-MRSA therapy. One hundred seven patients with MRSA nares PCR sensitivities were included in this assessment. The PPV and NPV were determined to be 25% CI (10.08-49.79%) and 94.7% CI (91.29-96.87%), respectively. Median and interquartile range durations of anti-MRSA therapy were decreased in the MRSA PCR negative group at 5 (3-8) versus 6.5 (6-9.75) days (p = 0.03752). This research showed a high NPV (94.7%) and a low PPV (25%) that aligned with other studies evaluating MRSA nares PCR utilization in osteomyelitis. Additionally, despite no active intervention on the results, early de-escalation of inappropriate antibiotic therapy was observed.

Comparison of Microbial Respiratory Cultures versus MRSA Nasal Screen to Guide Vancomycin De-escalation in Patients Hospitalized for Bacterial Pneumonia

Comparison of Microbial Respiratory Cultures versus MRSA Nasal Screen to Guide Vancomycin De-escalation in Patients Hospitalized for Bacterial Pneumonia

Nasal Methicillin-Resistant Staphylococcus aureus Culture Screens in the Setting of Universal Decolonization

Introduction The negative predictive value (NPV) of nasal methicillin-resistant Staphylococcus aureus (MRSA) screens has been compromised by universal decolonization practices. We aimed to determine the reliability of the nasal MRSA culture screen to deescalate antibiotic therapy in the setting of decolonization with ethyl alcohol. Methodology A retrospective observational cohort study was conducted using 62% ethanol solution intranasally per protocol. Patients were divided into 2 groups based on whether they received decolonization. Data were analyzed to determine NPV of the nasal MRSA culture screen with and without decolonization. Results A total of 505 cases were screened, and 128 subjects were included. One hundred two received decolonization, whereas 26 did not. Baseline characteristics were well balanced. Overall MRSA infection prevalence was 31.25%. The NPV was 73% in the decolonized group compared with 80% in the group without. Positive predictive value was 63% in the group receiving decolonization compared with 100% in the group without. There was also a higher specificity but lower sensitivity of the nasal MRSA culture screen in the decolonization group. Nine patients in the decolonization group required reescalation of antibiotics compared with nil in the other group. Conclusions Culture-based nasal MRSA screens are less accurate than PCR tests, as ethyl alcohol leads to false-negative results. A lower NPV in the decolonization group predisposes to increased false negative results, leading to inappropriate antibiotic deescalation and often requiring reinitiation. Nasal MRSA culture screen is less reliable if alcohol has already been administered for decolonization and cannot be used as an appropriate tool to guide antibiotic deescalation.

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

Using Methicillin-Resistant Staphylococcus aureus Nasal Screens to Rule Out Methicillin-Resistant S aureus Pneumonia in Surgical Intensive Care Units

IntroductionThe methicillin-resistant Staphylococcus aureus (MRSA) polymerase chain reaction (PCR) has a high negative predictive value (NPV). We aimed to understand if there was a difference in the NPV of the MRSA screen in surgical intensive care units (ICUs) and to determine its role in antibiotic de-escalation. MethodsWe performed a single-center, retrospective cohort study of adults with a positive respiratory culture and MRSA nasal PCR admitted to a surgical ICU from 2016 to 2019. Patients were stratified by surgical ICU: cardiothoracic/cardiovascular intensive care unit (CVICU) or transplant/acute care surgery intensive care unit (ACS-ICU). Our primary outcome was the NPV of MRSA screen. Secondary outcome was the duration of empiric MRSA-targeted therapy. ResultsWe analyzed 61 patients: 42.6% (n = 26) ACS-ICU and 57.4% (n = 35) CVICU. There were no differences in age, comorbidities, prior MRSA infection, recent antibiotic use, immunocompromised status, or renal replacement therapy. At pneumonia diagnosis, more patients in the ACS-ICU were hospitalized ≥5 d (65.4% versus 8.6%, P < 0.0001) and more patients in the CVICU were in septic shock (88.6% versus 34.5%, P < 0.0001) and thrombocytopenic (40% versus 11.5%, P = 0.02). NPV of the PCR was similar (ACS-ICU: 0.92 [0.75-0.98], CV-ICU 0.89 [0.73-0.96]). On multivariable linear regression, the CVICU was associated with longer empiric therapy (β 1.5, 95% CI 0.8-2.3, P < 0.0001), as was hospitalization for ≥5 d (β 0.73, 95% CI 0.06-1.39, P = 0.03). ConclusionsThe MRSA nasal PCR screen has a high NPV for ruling out MRSA pneumonia in critically ill surgical patients. However, patients in the CVICU and patients hospitalized ≥5 d had a longer time to de-escalation of MRSA-targeted therapy, potentially due to higher clinical risk profile.

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

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

Hiding in Plain Sight: Benefit of Abrasion and Laceration Swabs in Identification of Panton-Valentine Leucocidin (PVL)-Meticillin Resistant Staphylococcus aureus (MRSA) Colonisation in Military Personnel.

Background Outbreaks of Panton-Valentine Leucocidin (PVL)-producing methicillin-resistantStaphylococcus aureus(MRSA) skin and soft tissue infections (SSTIs) are a recurrent challenge for the Royal Marines at the Commando Training Centre (CTCRM). The intensity of commando training, its impact on skin integrity, and persistent colonisation reservoirs within the training centre have thwarted attempts to prevent these outbreaks. Aim To present an outbreak of PVL-producing MRSA SSTIs at a military training centre, demonstrating the benefit of additional abrasion and laceration swabs on the identification of colonised personnel and showing the effectiveness of a 10-day decolonisation regime. Method Following the identification of the outbreak of PVL-producing MRSA, all 36 members of the Recruit Troop underwent nasal MRSA screening to identify MRSA carriers. The screening was repeated on day 16 after completing an enhanced 10-day decolonisation regime. A third screening was conducted on the 110th day after a second peak of infection was identified. Various infection control measures, such as enhanced cleaning, restriction of movement and adjustments to the military training serials, were introduced to prevent further spread through the training centre. Results In this outbreak, two-thirds (eighteen) of the Recruit Troop suffered MRSA-PVL skin infections requiring antibiotic therapy and three required hospital admission for surgical management of their abscesses. The outbreak lasted 130 days, with two spikes in infections 10 weeks apart. The outbreak was successfully confined to one troop. Conclusion With concerns about low identification rates of carriers using nasal screening for MRSA, in this outbreak, we improved the identification of asymptomatic carriage with the simple step of additional culture swabs for all cuts and abrasions. Improved identification of colonised recruits, along with an enhanced decolonisation regime and rigid infection control practices, prevented the further spread of the clone through the training centre. In a population with constant ongoing skin trauma, such as the military, contact sport athletes and iIV drug users, our results show that a culture of suitable abrasions/lacerations will improve the identification of MRSA colonisation compared with nasal swabs alone. Despite ongoing skin trauma and the logistical difficulties in delivering effective decolonisation during military training, decolonisation was successful in 79% of recruits after one decolonisation and 87% after the second 10-day decolonisation.

Effective screening methods to prevent surgical site infections in orthopedic surgery: an observational study

BackgroundThe bacterial source of surgical-site infections (SSIs) can have either endogenous and/or exogenous origins, and some studies have revealed that endogenous transmission is an important pathway for SSIs in orthopedic surgery. However, since the frequency of SSIs is low (0.5–4.7%), screening all surgery patients is labor-intensive and cost-prohibitive. The goal of this study was to better understand how to improve the efficacy of nasal culture screening in preventing SSIs.MethodsNasal cultures for 1616 operative patients over a 3-year period were evaluated for the presence of nasal bacterial microbiota and the species identity. We also investigated the medical factors that influence colonization and evaluated the ratio of agreement between nasal cultures and SSI-causing bacteria.ResultsIn a survey of 1616 surgical cases, 1395 (86%) were normal microbiota (NM), 190 (12%) were MSSA carriers, and 31 (2%) were MRSA carriers. The risk factors for MRSA carriers were significantly higher than the NM group in patients with a history of hospitalization (13 [41.9%], p = 0.015), patients who had been admitted to a nursing facility (4 [12.9%], p = 0.005), and patients who were > 75 years of age (19 [61.3%], p = 0.021). The incidence of SSIs was significantly higher in the MSSA group (17/190 [8.4%]) than the NM group (10/1395 [0.7%], p = 0.00). The incidence of SSIs in the MRSA group (1/31 [3.2%]) tended to be higher than that in the NM group, but there was no statistically significant difference (p = 0.114). The concordance rate between causative bacteria of SSI and species present in nasal cultures was 53% (13/25 cases).ConclusionsThe results of our study suggest screening patients with a history of past hospitalization, a history of admission in a long-term care facility, and older than 75 to reduce SSIs.Trial registrationThis study was approved by the institutional review board of the authors’ affiliated institutions (the ethics committee of Sanmu Medical Center, 2016-02).

Prevalence of multidrug-resistant Escherichia coli isolated from Jember hospital food handler in Indonesia

Introduction: Foodborne illness is a significant global public health issue. Improper food handling and personal cleanliness can result in a few ailments. Over 400 food-related infections have been found by the CDC, of which food handlers cause 20%. Escherichia coli is often found in hospital food handler hand and nasal swabs. This study aimed to ascertain the prevalence of E. coli and the antibiotic susceptibility profile of food handlers working in hospitals in Jember City, Indonesia. Method: A cross-sectional investigation uses a total sampling method held between October and November 2022. Inclusion criteria are asymptomatic food handlers that have not taken antibiotics for the last three months and have already given informed consent. Exclusion criteria are food handlers who’s sick or with incomplete questionnaires. We performed hand and nasal swabs and continued with bacteria identification, culture, and antibiotic sensitivity tests. Result: Ten food workers (14.71%) and fourteen (20.59%) of the 68 who underwent hand and nasal swab culture screenings for E. coli were positive. All E. coli hand swab isolates were susceptible to levofloxacin and azithromycin antibiotics. Still, of the 10 E. coli hand swab isolates, 90% were resistant to the antibiotics; penicillin, Cefotaxime, and ceftriaxone, while 70% were resistant to erythromycin. For E. coli isolates originating from nasal swabs, 85.71% were resistant to Cefotaxime, 71.43% to Penicillin and Cefepime, and 57.14% were resistant to Ceftriaxone and Erythromycin. E. coli Multiple Antibiotic Resistance (MAR) index for hand and nasal swab specimens is 0.18 – 0.82. Most of the hand swab specimens (90%) are Multidrug Resistant (MDR), while nasal swab specimen shows 78.57% Multidrug Resistant (MDR). Conclusion: The predominance of multidrug-resistant E. coli among hospital food handlers makes it imperative to implement infection control measures, including better biosecurity, to ensure that they do not enter the food supply and limit alternatives to inpatient therapy.

Identification of Risk Factors for Nasal Colonization of Methicillin-resistant Staphylococcus aureus and Vancomycin-resistant Staphylococcus aureus in Health Workers at a Tertiary Hospital, Indonesia

BACKGROUND: Methicillin-resistant Staphylococcus aureus (MRSA) and Vancomycin-resistant S. aureus (VRSA) frequently cause nosocomial infections yearly. During the COVID-19 pandemic, the potential for excessive use of antibiotics is a global threat to the increasing incidence of multiresistant bacteria. AIM: This study aimed to determine MRSA and VRSA colonization and identify factors associated with the risk of MRSA and VRSA nasal colonization in health workers at Dr. Soemarno Sosroatmodjo General Hospital, Kuala Kapuas, as one of the type C hospitals in Indonesia. METHODS: This cross-sectional analytic study at Dr. Soemarno Sosroatmodjo General Hospital, a tertiary hospital in Indonesia. A 128 health workers’ subjects had undergone nasal swab screening for MRSA and VRSA colonization examinations. Then, they were asked to complete a questionnaire concerning the risk factors of MRSA and VRSA infections. RESULTS: Nasal swab results obtained as many as 30 (23.5%) MRSA positive subjects and 6 (4.7%) subjects with positive VRSA. The most common risk factors that led to MRSA colonization included a history of positive MRSA in the previous hospital (60%), a history of ear, nose, and throat infection (41.7%), and did not do hand rub/handwash (36.7%). In comparison, the most risk factors for VRSA colonization were having pigs farm at home (33.3%), a history of positive MRSA in the previous hospital (20%), and a history of hospitalization in the past 6–12 months (16.7%). The results of multivariate analysis showed the most powerful and statistically significant risk factors in influencing nasal MRSA colonization were a history of positive MRSA in the previous hospital (OR 13.69, 95% confidence intervals [CI]: 1.34–140.25, p = 0.028) and did not do hand rub/handwash (OR 2.95, 95% CI: 1.167–7.49, p = 0.023). Meanwhile, marital status (OR 0.160, 95% CI: 0.02–1.06), p = 0.058) and home care service (OR 6.10, 95% CI: 0.79–46.96, p = 0.082) were the strongest risk factors for nasal colonization of VRSA but not statistically significant. CONCLUSION: As many as, 23.5% and 4.7% of healthcare workers’ subjects were found with nasal colonization of MRSA and VRSA, respectively. Accordingly, strict policies are needed to minimize the transmission of these organisms from the hospital setting to the community.

Methicillin-Resistant Staphylococcus aureus Nasal Swab Is Insufficient to Withhold Empiric Methicillin-Resistant Staphylococcus aureus Pneumonia Coverage in a Trauma Population

IntroductionMethicillin-resistant staphylococcus aureus (MRSA) nasal colonization is a predictor of MRSA pneumonia in intensive care unit (ICU) patients. Negative nasal swabs have shown up to a 97% negative predictive value for MRSA pneumonia in nontrauma populations, though little investigation has been pursued in trauma patients. Materials and methodsAll trauma patients admitted to the ICU from April 2018 to February 2019 were screened for MRSA colonization by nasal swab. Patients with suspicion for pneumonia underwent bronchoalveolar lavage or quantitative sputum culture and were started on empiric antibiotic therapy based on the swab result. Swab-positive patients were started on empiric MRSA coverage and swab-negative patients were not. ResultsMRSA nasal swab screening was performed in 601 trauma ICU patients. Ninety-six patients subsequently underwent pneumonia workup and were started on an empiric antibiotic regimen based on nasal swab results. Seventeen (17.7%) patients were MRSA nasal swab positive on screening, and 22 (22.9%) patients subsequently had significant growth of MRSA on quantitative respiratory culture. The sensitivity of nasal swab was 50.0% and the specificity was 91.9%. Eleven patients had a negative MRSA nasal swab but a positive MRSA pneumonia (11.5%). Patients with inadequate antibiotic coverage had statistically longer hospital length of stay, ICU length of stay, ventilator days, and rates of unplanned intubation compared to patients with adequate antibiotic coverage. ConclusionsNasal swab screening was not sensitive enough in a trauma population with a high endemic incidence of MRSA colonization to warrant withholding empiric antibiotic MRSA coverage in patients with suspected pneumonia.