Bacteremia Research Articles

Diagnostic and prognostic value of time to positivity in blood cultures. An opinion paper

Time to positivity (TTP) refers to the duration required for a microbiological culture test to indicate a positive result, marking the onset of detectable bacterial or fungal growth in the sample. Numerous variables, including patient characteristics, infection source, former antimicrobial therapy, blood sample volume, and sample transportation time can influence the value of TTP. Several studies have been conducted on bloodstream infections, whereas studies on the clinical significance of yeast TTP are quite limited in the literature. Furthermore, many studies are retrospective and have a small sample size. In this opinion paper, we have formulated some questions and attempted to provide answers based on the available literature and our perspective. The objective of this opinion paper is to summarise current knowledge based on the literature, aiming to offer a critical perspective, particularly on aspects with weaker evidence, which could guide future studies in this area. We believe that TTP of blood cultures appears to exhibit considerable potential and may prove to be a valuable tool in clinical practice for estimating patient mortality risk and guiding antimicrobial therapy choices. Topics discussed include the diagnostic and prognostic role of TTP in Gram-positive and Gram-negative bacteremias and in candidemias, and the significance of differential time to positivity (DTTP). In summary, our opinion is that, based on the available literature, it is not possible to determine whether TTP provides prognostic information, particularly concerning candidemia. Therefore, clinical decisions cannot be systematically based on this parameter.

Structural Equation Modelling as a Proof-of-Concept Tool for Mediation Mechanisms Between Topical Antibiotic Prophylaxis and Six Types of Blood Stream Infection Among ICU Patients

Whether exposing the microbiome to antibiotics decreases or increases the risk of blood stream infection with Pseudomonas aeruginosa, Staphylococcus aureus, Acinetobacter, and Candida among ICU patients, and how this altered risk might be mediated, are critical research questions. Addressing these questions through the direct study of specific constituents within the microbiome would be difficult. An alternative tool for addressing these research questions is structural equation modelling (SEM). SEM enables competing theoretical causation networks to be tested ‘en bloc’ by confrontation with data derived from the literature. These causation models have three conceptual steps: exposure to specific antimicrobials are the key drivers, clinically relevant infection end points are the measurable observables, and the activity of key microbiome constituents on microbial invasion serve as mediators. These mediators, whether serving to promote, to impede, or neither, are typically unobservable and appear as latent variables in each model. SEM methods enable comparisons through confronting the three competing models, each versus clinically derived data with the various exposures, such as topical or parenteral antibiotic prophylaxis, factorized in each model. Candida colonization, represented as a latent variable, and concurrency are consistent promoters of all types of blood stream infection, and emerge as harmful mediators.

Utility of Obtaining Follow-Up Blood Cultures in Gram-Negative Bacterial Bloodstream Infection Among Patients With Hematologic Malignancies

Utility of Obtaining Follow-Up Blood Cultures in Gram-Negative Bacterial Bloodstream Infection Among Patients With Hematologic Malignancies

Clinical features and risk factors of Klebsiella pneumoniae infection in premature infants: a retrospective cohort study.

With the continuous advancement of modern medical technology, the survival rate of premature infants has significantly increased. Klebsiella pneumoniae (K. pneumoniae) is one of the most common pathogens causing neonatal infections, particularly posing a serious risk to premature infants. This study aimed to analyze the clinical characteristics, antibiotic susceptibility profiles, and treatment outcomes of K. pneumoniae infections in these infants. We retrospectively compared cases of K. pneumoniae infection in premature and term infants admitted in a tertiary hospital from January 2017 to December 2022 in China. Clinical and microbiological characteristics were evaluated. Data analysis was performed using the Statistical Package for the Social Sciences (SPSS), with statistical significance defined as P < 0.05. We enrolled 166 premature infants and 68 term infants. In premature infants, fetal distress, patent ductus arteriosus, patent foramen ovale, enteritis, anemia, hypoproteinemia, bloodstream infections, abdominal infection, mechanical ventilation, nasogastric feeding, drainage tube, parenteral nutrition, and prior exposure to carbapenem antibiotics were identified as significant risk factors for K. pneumoniae infections in univariate analysis. Furthermore, septic shock, bloodstream infections, abdominal infections, indwelling catheters, drainage tubes, parenteral nutrition, and previous exposure to glycopeptide antibiotics were significantly correlated with mortality. Independent risk factors for K. pneumoniae infections in premature infants included fetal distress (OR: 3.702, [95% CI: 1.056-12.986], P = 0.041), enteritis (OR: 4.434, [95% CI: 1.066-18.451], P = 0.041), anemia (OR: 4.028, [95% CI: 1.550-10.466], P = 0.004), bloodstream infections (OR: 1.221, [95% CI: 0.061-1.802], P = 0.022), mechanical ventilation (OR: 4.974, [95% CI: 1.685-14.685], P = 0.004) and prior exposure to carbapenem antibiotic (OR: 14.738, [95% CI: 2.393-90.767], P = 0.004). Additionally, abdominal infections (OR: 8.598, [95% CI: 2.000-36.957], P = 0.004) and indwelling catheters (OR: 7.698, [95% CI: 0.998-59.370], P = 0.050) were positive predictors of mortality. K. pneumoniae isolates exhibit a notable prevalence of infection, poor treatment outcomes, and elevated resistance in preterm neonates. These findings enhance our understanding of K. pneumoniae infections and their association with clinical outcomes among premature infants.

Isolation and Identification of Bacterial Pathogens from Blood Cultures in a Tertiary Care Hospital and Their Clinical Correlation

Objective: This study aimed to isolate and identify bacterial pathogens from blood cultures of patients with suspected bloodstream infections (BSIs) in a tertiary care hospital, analyze their antimicrobial susceptibility patterns, and establish clinical correlations. Methods: A cross-sectional study was conducted in the Microbiology Department of a tertiary care hospital. Blood samples from 60 patients were collected aseptically, processed using BACTEC, and cultured on blood and MacConkey agar. Bacterial isolates were identified based on colonial morphology, Gram staining, and biochemical tests. Antibiotic susceptibility testing was performed using the modified Kirby-Bauer disk diffusion method according to Clinical and Laboratory Standards Institute (CLSI) guidelines. Results: The overall culture positivity rate was 26%, with higher positivity among female patients (31.57%) and neonates or infants under six months (26%). Klebsiella pneumoniae was the most frequently isolated pathogen (53.33%), followed by Staphylococcus aureus (20.00%), Escherichia coli (13.33%), and Citrobacter species (13.33%). Klebsiella pneumoniae showed high resistance to ceftazidime and piperacillin, while remaining sensitive to cefoperazone and tobramycin. Staphylococcus aureus isolates were resistant to penicillin and erythromycin but sensitive to vancomycin and cefazolin. The prevalence of multidrug resistance among isolates underscores the need for targeted empirical therapy. Conclusion: Klebsiella pneumoniae emerged as the primary pathogen in BSIs, with significant resistance to commonly prescribed antibiotics. These findings highlight the necessity for enhanced infection control measures, especially in NICUs, and the implementation of local antibiograms to guide effective antibiotic therapy and mitigate resistance trends. Further research across multiple centers is recommended to validate these findings and inform broader clinical guidelines.

Machine learning-based model for predicting the occurrence and mortality of nonpulmonary sepsis-associated ARDS.

The objective was to establish a machine learning-based model for predicting the occurrence and mortality of nonpulmonary sepsis-associated ARDS. 80% of sepsis patients selected randomly from the MIMIC-IV database, without prior pulmonary conditions and with nonpulmonary infection sites, were used to construct prediction models through machine learning techniques (including K-nearest neighbour, extreme gradient boosting, support vector machine, deep neural network, and decision tree methods). The remaining 20% of patients were utilized to validate the model's accuracy. Additionally, local data were employed for further model validation. A total of 11,409 patients were included, with the most common type of infection being bloodstream infection. A total of 7,632 (66.9%) patients developed nonpulmonary sepsis-associated ARDS (NPS-ARDS). Patients with NPS-ARDS had significantly longer ICU stays (6.2 ± 5.2 days vs. 4.4 ± 3.7 days, p < 0.01) and higher 28-day mortality rates (19.5% vs. 14.9%, p < 0.01). Both internal and external validation demonstrated that the model constructed with the extreme gradient boosting method had high accuracy. In the internal validation, the model predicted NPS-ARDS and mortality in such patients with accuracies of 77.5% and 71.8%, respectively. In the external validation, the model predicted NPS-ARDS and mortality in these patients with accuracies of 78.0% and 81.4%, respectively. The model established via the extreme gradient boosting method can predict the occurrence and mortality of nonpulmonary sepsis-associated ARDS to a certain extent.

Application of metagenomic next-generation sequencing in the diagnosis of infectious diseases

Metagenomic next-generation sequencing (mNGS) is a transformative approach in the diagnosis of infectious diseases, utilizing unbiased high-throughput sequencing to directly detect and characterize microbial genomes from clinical samples. This review comprehensively outlines the fundamental principles, sequencing workflow, and platforms utilized in mNGS technology. The methodological backbone involves shotgun sequencing of total nucleic acids extracted from diverse sample types, enabling simultaneous detection of bacteria, viruses, fungi, and parasites without prior knowledge of the infectious agent. Key advantages of mNGS include its capability to identify rare, novel, or unculturable pathogens, providing a more comprehensive view of microbial communities compared to traditional culture-based methods. Despite these strengths, challenges such as data analysis complexity, high cost, and the need for optimized sample preparation protocols remain significant hurdles. The application of mNGS across various systemic infections highlights its clinical utility. Case studies discussed in this review illustrate its efficacy in diagnosing respiratory tract infections, bloodstream infections, central nervous system infections, gastrointestinal infections, and others. By rapidly identifying pathogens and their genomic characteristics, mNGS facilitates timely and targeted therapeutic interventions, thereby improving patient outcomes and infection control measures. Looking ahead, the future of mNGS in infectious disease diagnostics appears promising. Advances in bioinformatics tools and sequencing technologies are anticipated to streamline data analysis, enhance sensitivity and specificity, and reduce turnaround times. Integration with clinical decision support systems promises to further optimize mNGS utilization in routine clinical practice. In conclusion, mNGS represents a paradigm shift in the field of infectious disease diagnostics, offering unparalleled insights into microbial diversity and pathogenesis. While challenges persist, ongoing technological advancements hold immense potential to consolidate mNGS as a pivotal tool in the armamentarium of modern medicine, empowering clinicians with precise, rapid, and comprehensive pathogen detection capabilities.

Comparison of intra-assay and inter-assay reproducibility and positive detection times of two different (BacT/Alert 3D and Autobio BC) commercial blood culture systems.

In our study, we aimed to compare the performance of the BacT/Alert 3D (bioMerieux, France) system, which is currently used in our laboratory, and the Autobio BC (Autobio, China) system, which was newly introduced in our country, using standard and clinical isolates. Bacterial suspension was prepared by two technicians on the same day and three consecutive days from five different standard strains with 0.5 McFarland turbidity, then serial dilution to a final concentration was adjusted and was simultaneously inoculated in aerobic blood culture bottles. The bacterial concentration was measured by making a quantitative counting plate. The same procedure was also performed for 55 clinical isolates belonging to eleven species. After simulated bacteremia with standard and clinical isolates, the growth results were confirmed by inoculation from positive blood culture bottles onto solid medium and identification was made in the next day with MALDI-TOF MS (bioMérieux). In each study, sterile saline and blood was inoculated into the bottles as a negative control to check contamination. Intra-assay and inter-assay reproducibility of recovery rates and detection times of standard strains; recovery rates and detection times of clinical isolates were compared for both systems. Recovery rates were 100% in both systems, and when positive detection times were compared, it was found that there was no difference between the two devices in clinical isolates (p:0.262) but that Autobio BC gave significantly (p<0.001) earlier results in standard strains. In our simulated bloodstream infection study, Autobio BC was found to be comparable with BacT/Alert 3D, both recovery rates and growth detection time performance were found to be very good, and it can be used in routine microbiology laboratories.

Diversity, Distribution, and Resistance Profiles of Bacterial Bloodstream Infections in Three Tertiary Referral Hospitals in Rwanda Between 2020 and 2022

Diversity, Distribution, and Resistance Profiles of Bacterial Bloodstream Infections in Three Tertiary Referral Hospitals in Rwanda Between 2020 and 2022

Frequency and risk factors of nosocomial infections in atrauma center: acase study from the Beni Suef University Hospital, Egypt.

Hospital-acquired infections (HAI) cause asignificant risk to patient maintenance and wellbeing, particularly within the specialized environment of atrauma center. This study focuses on investigating the frequency of HAI in atrauma center through acomprehensive surveillance and monitoring system. This observational study, conducted between January 2023 and June 2023, focused on the 16-bed trauma center. HAI diagnoses were based on the centers for disease control and prevention (CDC) definitions that typically include specific criteria for different types of infections, for example, urinary tract infections, surgical site infections, bloodstream infections, and others. Among the 160 trauma center-admitted patients, 89were included in the study. 44patients contracted HAI, resulting in afrequency of 49.4%. The incidence rates (IR) were 21/1000 central venous catheter (CVC) days for catheter-related bloodstream infections (CRBSI), 10/100 urinary catheter days for catheter-associated urinary tract infections (CAUTI), and 34/1000 ventilator days for ventilator-associated pneumonia (VAP). The HAI percentages noticed in the trauma center are comparatively lower than those reported in other developing country hospitals. The incidence of VAP aligns with findings from other studies.

Burden and Risk Factors for Coinfections in Patients with a Viral Respiratory Tract Infection

Which patients should be monitored for coinfections or should receive empirical antibiotic treatment, in patients with an acute viral respiratory infection, is largely unknown. We evaluated the prevalence, characteristics, outcomes of coinfected patients, and risk factors associated with a coinfection among patients with an acute viral infection. A retrospective, single-center study recruited consecutive patients from October 2022 to March 2023 presenting to the emergency department with signs of a respiratory tract infection. Patients were screened for respiratory viruses and bacterial/fungal secondary infections according to local standard procedures. Outcomes included severe disease, in-hospital complications, all-cause in-hospital and ICU-related mortality, time to death, time to discharge, and time to coinfection. The analysis included 652 patients. A viral infection and a secondary bacterial/fungal infection were detected in 39.1% and 40% of cases. Compared with the rest of the cohort, coinfected patients had more frequently severe disease (88.3%, p &lt; 0.001; 51% in patients with SARS-CoV-2) and higher in-hospital mortality (16.5%, p = 0.010). Nephropathy (OR 3.649, p = 0.007), absence of COVID-19 vaccination (OR 0.160, p &lt; 0.001), SARS-CoV-2 infection (OR 2.390, p = 0.017), and lower blood pressure at admission (OR 0.980, p = 0.007) were independent risk factors for coinfection. Multidrug-resistant pathogens were detected in 30.8% of all coinfections. Patients with a viral infection are at high risk of bacterial coinfections, which carry a significant morbidity and mortality burden.

Bacteriological Profile and Antibiotic Susceptibility Pattern of Isolates from Suspected Neonatal Septicemia Patients in Different Hospitals of Chattogram

Background: Bacterial blood stream infection is an important cause of morbidity and mortality in neonates. This study was undertaken to identify the bacterial isolates from suspected neonatal septicemia patients and to understand their antimicrobial susceptibility pattern in Chattogram. Materials and methods: A cross-sectional descriptive type of study was done for a period of two years from January 2022 to December 2023. Blood samples from 340 neonates with clinically suspected septicemia were taken for automated culture and susceptibility test was conducted in Bacteriology Laboratory of IbneSina, Chattogram. The samples were collected and processed following standard microbiological techniques and an antibiotic susceptibility test was done on pure culture isolates using disc-diffusion method for the commonly used antibiotics. The data were analyzed by using SPSS version 20 and the results were summarized by using tables and graphs. Results: Out of 340 blood culture done, 62 (18.24%) were positive. Among them 61.3% were of early onset sepsis. The predominant bacteria isolated was Klebsiella spp. 27 (43.6%) followed by Coagulase negative staphylococci 12(19.4%), Salmonella typhi 10 (16.1%), E. coli 6 (9.6%) and Pseudomonas 5 (8.0%). Antibiotic susceptibility tests showed that the most sensitive antibiotics to Gram-negative organisms wereImipenem (81-100%), Tazobactam-Piperacillin (74-100%), Amikacin (67-90%), Ceftriaxone (60-100%) and Levofloxacin (63-80%). Maximum resistance among Gram-negative organisms were seen in Ampicillin (60-100%), Cotrimoxazole (60-100%) and Cefixime (30-80%). Among Gram-positive organisms, all strains (100%) were sensitive to Linezolid and Vancomycin. Other alternates with good sensitivity were Amikacin (92%), Imipenem (83%), Ceftriaxone (83%) and Levofloxacin (75%). While maximum resistance was seen to Ampicillin (83%), Amoxiclav (75%), Cefixime (75%) and Ciprofloxacin (75%). Conclusions: In the present study, most of the pathogens isolated from blood cultures were Gram negative and they showed high resistance to commonly used antibiotics. Therefore, rational use of antibiotics after sensitivity testing should be practiced. IAHS Medical Journal Vol 7(1), June 2024; 68-73

Which is the safer option for adult patients between peripherally inserted central catheters and midline catheters: a meta-analysis.

Peripherally inserted central catheters (PICC) and midline catheters (MC) are widely used for intravenous infusions in oncology and critically ill patients. However, controversy remains regarding which method is superior. This meta-analysis systematically compares the safety differences between these 2 methods of intravenous catheterization. Eligible studies comparing PICC and MC were identified through searches in 6 databases. Thrombosis is the primary endpoint, while secondary endpoints include other complications, cost, and satisfaction rate. Fourteen studies with 20,675 patients were analyzed. Based on patient data, the MC group exhibited higher rates of catheter-related superficial vein thrombosis (SVT) (risk ratio [RR]: 0.42 [0.28, 0.64]), infiltrations (RR: 0.27 [0.12, 0.62]), and leaks (RR: 0.16 [0.05, 0.53]). In contrast, the PICC group had more catheter-related bloodstream infections (RR: 1.95 [1.15, 3.32]). Considering catheter days, the MC group showed increased total complications (RR: 0.51 [0.26, 0.99]), catheter-related thrombosis (deep vein thrombosis [DVT]+SVT) (RR: 0.41 [0.18, 0.95]), and leaks (RR: 0.17 [0.05, 0.64]). In the PICC group, the top 3 complications were catheter occlusions (20 per 1,000 catheter days [CDs]), pain (15 per 1,000 CDs), and phlebitis (11 per 1,000 CDs); for the MC group, they were leaks (33 per 1,000 CDs), premature removals (22 per 1,000 CDs), and catheter-related DVT (22 per 1,000 CDs). Additionally, the PICC group had higher dissatisfaction rates (RR: 4.77 [2.33, 9.77]) and increased costs. Compared to MC, PICC appears to be a safer intravenous catheterization option for adult patients, exhibiting fewer complications. However, the higher associated costs and lower satisfaction rates of PICC warrant serious attention.

Unveiling Ruminococcus gnavus Bacteremia: Clinical Characteristics and Implications.

Ruminococcus gnavus is a microbiota-forming, gram-positive coccus reportedly associated with several diseases, such as Crohn's disease. The number of in vitro studies on it is increasing. However, its clinical information is lacking in the literature, with only a few case reports published to date. To elucidate the significance of this organism, we describe its clinical characteristics in this study. During the study period (2013-2022), we identified 11 patients with R. gnavus bacteremia and conducted a retrospective chart review. Cases identified to be contaminated were excluded. We found 11 reports of R. gnavus bacteremia on PubMed and reviewed their clinical characteristics. Eleven R. gnavus bloodstream infection cases were identified in our facility. The median age of the patients was 83 years (interquartile range: 73.75-87.25). Seven cases had at least one documented intestinal lesion including three with malignancy cases, and two cases had uncompensated cirrhosis. In most cases, bacterial translocation was suspected as the entry mechanism. Among the 11 R. gnavus bloodstream infections, 7 (63.6%) were associated with intestinal lesions, and 2 (18.2%) had a history of suspected bacterial translocation without documented intestinal lesions. To the best of our knowledge, this is the largest cohort study on R. gnavus bloodstream infections. Intestinal entry was suspected in more than 80% of cases in both our cohort and the literature review cohort. For cases of bacteremia with an unknown etiology due to R. gnavus, a thorough examination of gastrointestinal lesions should be performed.

Clinical characteristics and prognosis analysis of pseudomonas aeruginosa bloodstream infection in adults: a retrospective study.

Pseudomonas aeruginosa bloodstream infections (PA BSIs) in adults, especially those complicated by sepsis, are associated with high rates of morbidity and mortality. Early identification of risk factors for both mortality and sepsis-induced coagulopathy (SIC) is critical to optimizing patient management and improving outcomes. We conducted a retrospective analysis of 118 adult patients diagnosed with PA BSIs at the Affiliated Hospital of Xuzhou Medical University from January 2022 to February 2024. Univariate analysis was employed to identify significant clinical factors, followed by multivariate stepwise logistic regression to determine independent predictors of mortality and SIC. Based on these findings, nomogram models were constructed and evaluated using the area under the receiver operating characteristic curve (AUC), Bootstrap resampling, and calibration plots to assess model performance. Empiric sensitive antibiotic therapy (ESAT) (OR = 0.039, P < 0.001), coronary artery disease (CAD) (OR = 10.315, P = 0.010), and invasive mechanical ventilation (OR = 3.926, P = 0.020) emerged as significant predictors of mortality. In contrast, elevated C-reactive protein (CRP) (OR = 1.011, P = 0.003), procalcitonin (PCT) (OR = 1.030, P = 0.005), and lower hemoglobin levels (OR = 0.963, P = 0.004) were independently associated with SIC. The AUC of mortality prediction model is 0.908, while the SIC prediction model yielded an AUC of 0.817. The predictive models developed in this study demonstrate early identification of mortality rates and SIC risk in PA BSI patients, which may have the potential to guide timely therapeutic interventions and improve clinical outcomes in this high-risk population.

Clinical characteristics associated with peripartum maternal bloodstream infection

ObjectiveBloodstream infection (BSI) during the peripartum period is a major cause of maternal morbidity and mortality. However, data on maternal BSI during hospitalization for delivery are limited. This study aimed to investigate the incidence, clinical characteristics, risk factors, microbiological features, and antibiotic resistance patterns of maternal peripartum BSI, with a focus on understanding the role of premature rupture of membranes (PROM), fever, and other risk factors in its development.MethodsWe investigated the clinical characteristics associated with maternal BSI during the peripartum period. This study included febrile women with blood cultures obtained during hospitalization for delivery. We analyzed the clinical characteristics, pathogenic microorganisms, antibiotic resistance, and maternal and neonatal outcomes of these patients. Participants were divided into BSI (n = 85) and non-BSI (n = 361) groups.ResultsSpontaneous rupture of membranes, PROM, PROM &amp;gt;24 h before labor, vaginal examinations &amp;gt;5 times, and cesarean sections during labor were more common in the BSI group. Escherichia coli (51.8%; 44/85) was the predominant causative pathogen, followed by Enterococcus faecalis (7.1%, 6/85). Approximately 31.2% of E. coli were resistant to levofloxacin, and 38.6% were extended-spectrum β-lactamase-producing bacteria. The BSI group had higher rates of maternal sepsis and Apgar scores ≤ 7 at 1 min than the non-BSI group. Furthermore, PROM, fever ≥38.9°C (102°F), and fever within 24 h after delivery were risk factors for postpartum BSI in the adjusted analysis.ConclusionMaternal BSI is a potentially life-threatening disease associated with PROM and the timing and severity of fever. Early identification and surveillance of pathogen composition and antimicrobial resistance can help prevent adverse outcomes.

Assessing the effect of implementing a central line care bundle on central line-associated bloodstream infections in a tertiary hospital in Saudi Arabia

Central line-associated bloodstream infections (CLABSIs) are severe bloodstream infections caused by catheter use and are often associated with a longer hospital stay, increased healthcare costs, and a higher mortality rate. However, catheter-related bloodstream infections can be successfully treated. It is essential that healthcare workers are aware of central line (CL) insertion and maintenance bundles to reduce and prevent the incidence of CLABSI. The objective of this study was to assess the impact of implementing CL care bundles on hospital-wide CLABSI incidence rates. This is a prospective study conducted at the King Faisal Specialist Hospital and Research Center in Saudi Arabia from January 2017 to December 2021. The research period was divided into two phases: the pre-intervention phase (January 1, 2017 to December 31, 2018) and the post-intervention phase (January, 2019 to December 31, 2020). During both phases, outcome variables, including CLABSI rate, were assessed. In the present study, the total number of CLABSIs is 439, of which 266 were in the pre-intervention phase and 173 were in the post-intervention phase. The overall CLABSI rate significantly decreased from 1.6±0.05 in the pre-intervention phase to 0.9±0.05 in the post-intervention phase. This decline in CLABSI was significant (p&lt;0.0001) across all hospital settings, including critical care and non-critical care units. The implementation of care bundles is essential and has been shown to significantly reduce CLABSI rates in nearly all participating units.

Microbial Trends and their Drug Resistance Responsible for Bloodstream Infections in a Superspeciality Transplant Hospital

Background &amp; Objective: Bloodstream infections (BSIs) are critical healthcare-associated infections that lead to high morbidity and mortality, requiring rapid diagnosis and effective antimicrobial treatment. The increasing prevalence of multidrug-resistant organisms (MDROs) exacerbates this issue, particularly in developing countries. The purpose of this study is to assess the bacteriological profile and antimicrobial susceptibility trends of BSIs to establish an antibiogram for effective empirical treatment. Materials and Methods: This study was conducted retrospectively on 3,300 blood culture samples from a multispecialty hospital over 15 months. Cultures were performed using Bactec FX and identification and antibiotic susceptibility determined by Vitek2 and Kirby-Bauer methods following CLSI guidelines. Results: Overall, the positivity rate was (14.3%) with 473 isolates: (400 bacterial and 73 fungal). Gram-negative bacteria were predominant, led by Klebsiella pneumoniae (113 isolates) and Escherichia coli (100 isolates). Among the Gram-negative bacteria, antimicrobial susceptibility was found to be low for Cephalosporins (21%sensitivity) and Fluoroquinolones (19.3% sensitivity), with moderate susceptibility to Carbapenems (51.3%). Sensitivity was high for Colistin (98.9%), Amikacin (91.05%), Tigecycline (100%), Fosfomycin (100%) and Ceftazidime-avibactum Aztreonam (97.7%). Among Gram-positive bacteria, Coagulase-negative Staphylococcal Species (CONS) and Staphylococcus aureus were the most common. The overall sensitivity of Gram-positive bacteria to antibiotics tested was high compared to the Gram-negative bacteria. Sensitivity to antibiotics such as Linezolid was found to be 94.5% and Vancomycin was found to be 93.5%. Conclusion: The high incidence of MDROs especially among the Gram-negative bacteria highlights the need for continuous monitoring and antibiotic stewardship programs. Empirical therapy must consider local resistance patterns, and a multidisciplinary approach is essential to mitigate antimicrobial resistance.

Abstract 4135466: Feasibility of Using Existing Infection Surveillance Methods for Percutaneous Coronary Intervention-related Infections

Background: Percutaneous coronary intervention (PCI) is a treatment that requires attention in terms of infection control, as it necessitates aseptic procedures similar to surgical operations. However, surveillance practices for PCI-related infections are uncommon, and no standardized surveillance program has been established. Purpose: To assess the feasibility of using existing surveillance methods to detect PCI-related infectious diseases. Method: To identify PCI-related bloodstream infections of local access sites, four existing case definitions, namely, laboratory-confirmed bloodstream infections (LCBI), clinical sepsis (CSEP), local access site infection (LASI), and exit site infection (ESI), were retrospectively applied to 1,037 patients who underwent PCI between April 2018 and March 2021. Of these, 167 experienced fever, underwent blood culture testing, and/or received antibiotics within 6 days of PCI. To confirm consistent evaluation, two independent infection control experts evaluated each case record according to the four case definitions. Results: Twenty-three patients (2.2%) were diagnosed with PCI-related infections, including two patients according to LCBI, 21 according to CSEP, and none according to LASI and ESI. Thirteen patients (LCBI: 1, CSEP: 12) received circulatory assist devices such as intra-aortic balloon pumping. Of the remaining 11 patients, 10 underwent emergency PCI, and one underwent elective PCI ( P =0.0001). The average length of hospital stay was 16.1 days for patients with PCI-related infections and 4.7 days for non-infected patients ( P &lt;0.05). Conclusion: The positive diagnosis of PCI-related infections was predominantly based on CSEP. Many of these positive patients underwent emergency PCI and/or received circulatory assist devices. The results of the present study warrant further investigations with larger patient cohorts.

The antimicrobial potential of traditional remedies of Indigenous peoples from Canada against MRSA planktonic and biofilm bacteria in wound infection mimetic conditions.

Methicillin-resistant Staphylococcus aureus (MRSA) is the leading cause of wound infections, often progressing into serious invasive bloodstream infections. MRSA disproportionately affects Indigenous peoples in Canada with higher rates of skin and wound infections, an example of persistent gaps in health outcomes between Indigenous and non-Indigenous peoples precipitated by the legacy of colonialism. Conversely, Indigenous peoples have long used natural remedies for infections and other diseases; however, their knowledge was rarely considered for modern medicine. The stagnant antibiotic discovery pipeline and alarming rise of resistance to current antibiotics prompted us to turn to Indigenous medicine as an untapped source of antimicrobials. As such, we collected and prepared 85 extracts of medicinal plants of value to Indigenous peoples spanning the Canadian Prairies. We explored the antimicrobial potential of these extracts against MRSA under wound infection-mimetic conditions compared with culture media typically used to study bacterial antibiotic responses and biofilms but not adequately representative of infection sites. We identified extracts with MRSA growth inhibitory [e.g., bergamot, dock, gaillardia, and dandelion extracts] and biofilm prevention and eradication [e.g., gumweed extracts] activities. Extracts, including those of chokecherry, hoary puccoon, and Northern bedstraw, were only active under wound infection-mimetic conditions, highlighting the benefit of antibiotic discovery under host-relevant conditions. Testing growth inhibitory extracts against an S. aureus cross-resistance platform suggested that they act through mechanisms likely distinct from known antibiotic classes. Together, through an interdisciplinary partnership leveraging Western approaches and traditional Indigenous knowledge, we identified plant extracts with promising antimicrobial potential for drug-resistant MRSA wound infections.IMPORTANCEWe explored the antimicrobial potential of traditional Indigenous remedies against MRSA under wound infection-mimetic conditions. We chose to tackle MRSA wound infections because they constitute an Indigenous health priority, ensuring mutual benefits and reciprocity, which are important principles in partnerships between Indigenous and non-Indigenous researchers. Our partnerships strive to serve as steps towards reconciliation with Indigenous peoples in Canada and a roadmap inspiring similar interdisciplinary collaborations to tackle other healthcare priorities. We identified extracts with promising antibacterial growth inhibitory, biofilm prevention, and eradication activities against MRSA. The antimicrobial potential of some extracts was only observed under wound infection-mimetic conditions, a proof-of-concept that screening under infection-mimetic conditions reveals novel activity undetected under standard conditions. The natural product antimicrobial extracts discovered herein warrant further investigation into their mode of action and chemical composition; they may address the dire need for new antimicrobial and anti-biofilm activity to counter the AMR crisis.