Clinical features and risk factors for mortality in patients with Klebsiella pneumoniae bloodstream infections.

INTRODUCTION: Concern about Klebsiella pneumoniae (K. pneumoniae) bloodstream infections (KP-BSIs) is widespread because of their high incidence and lethality. The aim of this study was to investigate the clinical features of, and risk factors for mortality caused by KP-BSIs. METHODOLOGY: This was a single-center retrospective observational study performed between 1 January 2019 and 31 December 2021, at a tertiary hospital. All patients with KP-BSIs were enrolled and their clinical data were retrieved from electronic medical records. RESULTS: A total of 145 patients were included (121 in the survival group and 24 in the non-survival group). There was a higher proportion of lower respiratory tract infections in the non-survival group than in the survival group (33.3% vs. 12.4%) (p < 0.05). There was a higher proportion of multi drug resistant (MDR) strains of K. pneumoniae in the non-survival group than in the survival group (41.7% vs. 16.5%) (p < 0.05). Multivariate analysis revealed that sequential organ failure assessment (SOFA) score > 6.5 (OR, 13.71; 95% CI, 1.05-179.84), admission to the intensive care unit (ICU) (OR, 2.27; 95% CI, 0.26-19.61) and gastrointestinal bleeding (OR, 19.97; 95% CI, 1.11-361.02) were independent risk factors for death in patients with KP-BSIs. CONCLUSIONS: Among all KP-BSIs, a high proportion of K. pneumoniae originated from lower respiratory tract infections, and a high proportion of K. pneumoniae were MDR; however, mortality was not influenced. SOFA score > 6.5, admission to the ICU, and gastrointestinal bleeding were independent risk factors for death in patients with KP-BSI.

Incidence, antimicrobial resistance and mortality of Klebsiella pneumoniae bacteraemia in Shanghai, China, 2018-2022.

BACKGROUND: Klebsiella pneumoniae (KP) accounts for high antimicrobial resistance and mortality rates of bloodstream infections (BSIs). OBJECTIVES: To investigate incidence, antimicrobial resistance and risk factors for mortality of KP BSIs in East China. METHODS: A retrospective study of patients with KP BSIs was conducted in a tertiary care hospital from 2018 to 2022. Medical records of all hospitalised patients with KP BSIs were reviewed and analysed. The incidence, antimicrobial resistance and mortality of KP BSIs were evaluated. The Kaplan-Meier method was used to plot survival curves and logistic regression was used to analyse risk factors for crude 30-day mortality. RESULTS: A total of 379 inpatients with KP BSIs were enrolled. The incidence of patients with KP BSIs was fluctuating between 4.77 and 9.40 per 100,000 patient-days. The crude 30-day mortality rate of these patients was 26.39%. Of the 379 KPisolates, 197 (51.98%) were carbapenem-resistant (CR) and 252 (66.49%) were multidrug-resistant (MDR). All isolates showed the lowest resistance to tigecycline (13.77%) and polymyxin B (14.61%). Cases with MDR/CR isolates had significantly longer length of hospital stay, higher crude 30-day mortality and medical costs than non-MDR/non-CR isolates. Age, CR phenotype, paracentesis, indwelling central venous catheter (CVC), use of carbapenems, tetracyclines, polymyxins B, and irrational empiric treatment were independently associated with crude 30-day mortality. CONCLUSION: MDR/CR KP BSIs are associated with increased mortality, healthcare costs and prolonged hospitalisation. Patients with advanced age, CR phenotype, paracentesis, CVC, exposure to some antibiotics, and irrational empirical antibiotic treatment are at higher mortality risk.

Hospital mortality and length of stay associated with Enterobacterales positive blood cultures: a multicenter analysis.

Delayed time to antimicrobial susceptibility results can impact patients' outcomes. Our study evaluated the impact of susceptibility turnaround time (TAT) and inadequate empiric antibacterial therapy (IET) in patients with bloodstream infections (BSI) caused by Enterobacterales (ENT) species on in-hospital mortality and length of stay (LOS). This retrospective, multicenter investigation which included 29,570 blood ENT-positive admissions across 161 US healthcare facilities evaluated the association between antimicrobial susceptibility testing (AST) TAT, carbapenem susceptibility, and empiric therapy on post-BSI in-hospital mortality and LOS following an ENT BSI event in adult patients. After adjusting for outcomes covariates, post-BSI in-hospital mortality was significantly higher for patients in the IET vs adequate empiric therapy (AET) group [odds ratio (OR): 1.61 (95% CI: 1.32, 1.98); P < 0.0001], and when AST TAT was >63 h [OR:1.48 (95% CI: 1.16, 1.90); P = 0.0017]. Patients with carbapenem non-susceptible (carb-NS) ENT BSI had significantly higher LOS (16.6 days, 95% CI: 15.6, 17.8) compared to carbapenem susceptible (carb-S, 12.2 days, 95% CI: 11.8, 12.6), (P < 0.0001). Extended AST TAT was significantly associated with longer LOS for TAT of 57-65 h and >65 h (P = 0.005 and P< 0.0001, respectively) compared to TAT ≤42 h (reference). Inadequate empiric therapy (IET), carb-NS, and delayed AST TAT are significantly associated with adverse hospital outcomes in ENT BSI. Workflows that accelerate AST TAT for ENT BSIs and facilitate timely and adequate therapy may reduce post-BSI in-hospital mortality rate and LOS.IMPORTANCEFor patients diagnosed with bloodstream infections (BSI) caused by Enterobacterales (ENT), delayed time to antimicrobial susceptibility (AST) results can significantly impact in-hospital mortality and hospital length of stay. However, this relationship between time elapsed from blood culture collection to AST results has only been assessed, to date, in a limited number of publications. Our study focuses on this important gap using retrospective data from 29,570 blood ENT-positive admissions across 161 healthcare facilities in the US as we believe that a thorough understanding of the dynamic between AST turnaround time, adequacy of empiric therapy, post-BSI event mortality, and hospital length of stay will help guide effective clinical management and optimize outcomes of patients with ENT infections.

Complete genome sequence of a Listeria monocytogenes serotype 1 isolated from a critically ill patient in Italy, 2023.

Listeria monocytogenes, a concerning foodborne pathogen, causes severe infections in vulnerable subjects such as pregnant women and the elderly. In this article, we present the complete genome sequence of P4_LIS, an L. monocytogenes isolated from a patient with invasive bacteria infection.

The effects of delayed appropriate antimicrobial therapy on children with Staphylococcus aureus blood infection.

Early appropriate antimicrobial therapy plays a critical role for patients with Staphylococcus aureus bloodstream infection (SAB). We aim to determine the optimal time-window for appropriate antimicrobial therapy and evaluate the effects of delayed therapy on adverse clinical outcomes (in-hospital mortality, sepsis, and septic shock) in children with SAB by propensity score matching (PSM) analysis. Receiver-operating characteristic was used to determine the cut-off point of the time to appropriate therapy (TTAT), the patients were divided into timely and delayed appropriate antimicrobial therapy (delayed therapy) groups accordingly. The PSM was used to balance the characteristics between the two groups, controlling the effects of potential confounders. Kaplan-Meier methods and Cox proportional hazards regression were applied to the matched groups to analyze the association between delayed therapy and clinical outcomes. Inverse probability of treatment weighting and propensity score covariate adjustment were also performed to investigate the sensitivity of the results under different propensity score-based approaches. In total, 247 patients were included in this study. The optimal cut-off point of TTAT was identified as 6.4 h, with 85.0% sensitivity and 69.2% specificity (AUC 0.803, 95% confidence interval 0.702-0.904). Eighty-seven (35.22%) of the 247 patients who received delayed therapy (TTAT ≥ 6.4 h) had higher in-hospital mortality (19.54% vs 1.88%, p < 0.001), higher incidences of sepsis (44.83% vs 15.00%, p < 0.001) and septic shock (32.18% vs 6.25%, p < 0.001) when compared to timely therapy (TTAT < 6.4 h) patients. After PSM analysis, a total of 134 episodes (67 in each of the two matched groups) were further analyzed. No statistically significant difference was observed in in-hospital mortality between delayed and timely -therapy groups (log-rank test, P = 0.157). Patients with delayed therapy had a higher incidence of sepsis or septic shock than those with timely therapy (log-rank test, P = 0.009; P = 0.018, respectively). Compared to the timely-therapy group, the hazard ratio and 95% confidence interval in delayed-therapy group were 2.512 (1.227-5.144, P = 0.012) for sepsis, 3.109 (1.166-8.290, P = 0.023) for septic shock.    Conclusion: Appropriate therapy delayed 6.4 h may increase the incidence of sepsis and septic shock, with similar in-hospital mortality in patients with SAB. What is Known: • Staphylococcus aureus (S. aureus) is a major cause of bloodstream infections in children. Undoubtedly, early antimicrobial application plays a critical role in the treatment of children with Staphylococcus aureus bloodstream infections (SAB). • However, rapid, and aggressive administration of antimicrobials may lead to the overuse of these drugs and the emergence of multidrug-resistant microorganisms. Therefore, it is crucial to determine the optimal time-window for appropriate antimicrobial administration in children with SAB. Unfortunately, the optimal time-window for appropriate antimicrobial administration in children with SAB remains unclear. What is New: • Determining the optimal time-window for appropriate antimicrobial administration in patients with matched data variables is particularly important. The Propensity score matching (PSM) analysis effectively controls for confounding factors to a considerable extent when assessing the impact of treatment, thereby approximating the effects observed in randomized controlled trials. • To our knowledge, this is the first study using PSM method to assess the effects of delayed appropriate antimicrobial therapy on adverse outcomes in children with SAB. In low-risk populations with SAB, a delay of 6.4 h in appropriate therapy might increase the occurrence rate for sepsis and septic shock; however, no correlation has been found between this delay and an increased risk for hospital mortality.

Molecular Characteristics of Salmonella Spp. Responsible for Bloodstream Infections in a Tertiary Hospital in Nanjing, China, 2019-2021.

Objective: To investigate the clinical and molecular characteristics of Salmonella spp. causing bloodstream infections (BSIs) in our hospital. Methods: We studied 22 clinical Salmonella isolates from BSIs and 16 from non-BSIs, performing antimicrobial susceptibility testing (AST) and whole genome sequencing (WGS). The analysis included serovars, antibiotic resistance genes (ARGs), virulence factors (VFs), sequence types (STs), plasmid replicons, and genetic relationships. We also assessed pathogenicity of the isolates causing BSIs through growth, biofilm formation, and anti-serum killing assays. Results: WGS analysis identified 13 Salmonella serovars, with four responsible for BSIs. S. Enteritidis was the most prevalent serovar, involved in 19 (50.0%) cases. BSIs were caused by 17S. Enteritidis, two S. Typhimurium, two S. Munster and one S. Diguel. Of the 38 isolates, 27 (71.1%) exhibited high resistance to ampicillin, and 24 (63.2%) to ampicillin/sulbactam. Thirty-six types of ARGs were identified, with blaTEM-1B (n = 25, 65.8%) being the most frequent. Ten plasmid replicons were found; the combination of IncFIB(S)-IncFII(S)-IncX1 was the most common in S. Enteritidis (94.7%). Fifteen STs were identified, among which ST11 was the most prevalent and clonally disseminated, primarily responsible for BSIs. A total of 333 different VFs were detected, 177 of which were common across all strains. No significant differences were observed between the BSI and non-BSI isolates in terms of resistance rates, ARGs, plasmid replicons, and VFs, except for seven VFs. No strong pathogenicity was observed in the BSI-causing isolates. Conclusion: BSIs were predominantly caused by clonally disseminated S. Enteritidis ST11, the majority of which carried multiple ARGs, VFs and plasmid replicons. This study provides the first data on clonally disseminated S. Enteritidis ST11 causing BSIs, highlighting the urgent need for enhanced infection control measures.

Clinical evaluation of droplet digital PCR in the early identification of suspected sepsis patients in the emergency department: a prospective observational study.

Background: Rapid and accurate diagnosis of the causative agents is essential for clinical management of bloodstream infections (BSIs) that might induce sepsis/septic shock. A considerable number of suspected sepsis patients initially enter the health-care system through an emergency department (ED), hence it is vital to establish an early strategy to recognize sepsis and initiate prompt care in ED. This study aimed to evaluate the diagnostic performance and clinical value of droplet digital PCR (ddPCR) assay in suspected sepsis patients in the ED. Methods: This was a prospective single-centered observational study including patients admitted to the ED from 25 October 2022 to 3 June 2023 with suspected BSIs screened by Modified Shapiro Score (MSS) score. The comparison between ddPCR and blood culture (BC) was performed to evaluate the diagnostic performance of ddPCR for BSIs. Meanwhile, correlative analysis between ddPCR and the inflammatory and prognostic-related biomarkers were conducted to explore the relevance. Further, the health economic evaluation of the ddPCR was analyzed. Results: 258 samples from 228 patients, with BC and ddPCR performed simultaneously, were included in this study. We found that ddPCR results were positive in 48.13% (103 of 214) of episodes, with identification of 132 pathogens. In contrast, BC only detected 18 positives, 88.89% of which were identified by ddPCR. When considering culture-proven BSIs, ddPCR shows an overall sensitivity of 88.89% and specificity of 55.61%, the optimal diagnostic power for quantifying BSI through ddPCR is achieved with a copy cutoff of 155.5. We further found that ddPCR exhibited a high accuracy especially in liver abscess patients. Among all the identified virus by ddPCR, EBV has a substantially higher positive rate with a link to immunosuppression. Moreover, the copies of pathogens in ddPCR were positively correlated with various markers of inflammation, coagulation, immunity as well as prognosis. With high sensitivity and specificity, ddPCR facilitates precision antimicrobial stewardship and reduces health care costs. Conclusions: The multiplexed ddPCR delivers precise and quantitative load data on the causal pathogen, offers the ability to monitor the patient's condition and may serve as early warning of sepsis in time-urgent clinical situations as ED. Importance: Early detection and effective administration of antibiotics are essential to improve clinical outcomes for those with life-threatening infection in the emergency department. ddPCR, an emerging tool for rapid and sensitive pathogen identification used as a precise bedside test, has developed to address the current challenges of BSI diagnosis and precise treatment. It characterizes sensitivity, specificity, reproducibility, and absolute quantifications without a standard curve. ddPCR can detect causative pathogens and related resistance genes in patients with suspected BSIs within a span of three hours. In addition, it can identify polymicrobial BSIs and dynamically monitor changes in pathogenic microorganisms in the blood and can be used to evaluate antibiotic efficacy and survival prognosis. Moreover, the copies of pathogens in ddPCR were positively correlated with various markers of inflammation, coagulation, immunity. With high sensitivity and specificity, ddPCR facilitates precision antimicrobial stewardship and reduces health care costs.

Adherence to guidelines and central-line-associated bloodstream infection occurrence during insertion and maintenance of intravascular catheters: evidence from 20 tertiary hospitals.

OBJECTIVE: To investigate adherence to intravascular catheter (IVC) insertion and maintenance guidelines in Chinese tertiary hospitals. METHODS: A cross-sectional questionnaire survey of adult inpatients with IVC placements was conducted from July to September 2022 in 20 tertiary hospitals in China. One clinical staff member from each department in each hospital was assigned to participate in the survey. Questionnaires were uniformly collected and reviewed after three months. RESULTS: This study included 1815 cases (62.69%) of central venous catheter, 471 cases (16.27%) of peripherally inserted central catheter, 461 cases (15.92%) of PORT, and 147 cases (5.08%) of haemodialysis catheter insertions. Statistically significant differences in compliance were observed across the four IVC types, specifically in relation to the insertion checklist, standard operating procedure, and insertion environment (P<0.05). Practice adherence during IVC maintenance differed significantly across the four IVC types in aspects such as availability of IVC maintenance verification forms, daily scrubbing of the catheterized patients, and catheter connection methods (P<0.05). A total of 386 (13.34%) patients developed fever, 1086 (37.53%) were treated with therapeutic antibiotics, 16 (0.55%) developed central-line-associated bloodstream infections, two (0.07%) developed local skin infections, and six (0.21%) developed deep vein thrombosis. CONCLUSIONS: Adherence to guidelines regarding insertion and maintenance differed across the four IVC types; there is a gap between the recommended measures and the actual operation of the guidelines. Therefore, it is necessary to further enhance training and develop checklists to prevent central-line-associated bloodstream infections.

Immunosuppression at ICU admission is not associated with a higher incidence of ICU-acquired bacterial bloodstream infections: the COCONUT study.

BACKGROUND: Immunosuppression at intensive care unit (ICU) admission has been associated with a higher incidence of ICU-acquired infections, some of them related to opportunistic pathogens. However, the association of immunosuppression with the incidence, microbiology and outcomes of ICU-acquired bacterial bloodstream infections (BSI) has not been thoroughly investigated. METHODS: Retrospective single-centered cohort study in France. All adult patients hospitalized in the ICU of Lille University-affiliated hospital for > 48 h between January 1st and December 31st, 2020, were included, regardless of their immune status. Immunosuppression was defined as active cancer or hematologic malignancy, neutropenia, hematopoietic stem cell and solid organ transplants, use of steroids or immunosuppressive drugs, human immunodeficiency virus infection and genetic immune deficiency. The primary objective was to compare the 28-day cumulative incidence of ICU-acquired bacterial BSI between immunocompromised and non-immunocompromised patients. Secondary objectives were to assess the microbiology and outcomes of ICU-acquired bacterial BSI in the two groups. RESULTS: A total of 1313 patients (66.9% males, median age 62 years) were included. Among them, 271 (20.6%) were immunocompromised at ICU admission. Severity scores at admission, the use of invasive devices and antibiotic exposure during ICU stay were comparable between groups. Both prior to and after adjustment for pre-specified baseline confounders, the 28-day cumulative incidence of ICU-acquired bacterial BSI was not statistically different between immunocompromised and non-immunocompromised patients. The distribution of bacteria was comparable between groups, with a majority of Gram-negative bacilli (~ 64.1%). The proportion of multidrug-resistant bacteria was also similar between groups. Occurrence of ICU-acquired bacterial BSI was associated with a longer ICU length-of-stay and a longer duration of invasive mechanical ventilation, with no significant association with mortality. Immune status did not modify the association between occurrence of ICU-acquired bacterial BSI and these outcomes. CONCLUSION: The 28-day cumulative incidence of ICU-acquired bacterial BSI was not statistically different between patients with and without immunosuppression at ICU admission.

Treatment of positive catheter tip culture without bloodstream infections in critically ill patients. A case-cohort study from the OUTCOMEREA network.

PURPOSE: This study aimed to evaluate the impact on subsequent infections and mortality of an adequate antimicrobial therapy within 48 h after catheter removal in intensive care unit (ICU) patients with positive catheter tip culture. METHODS: We performed a retrospective analysis of prospectively collected data from 29 centers of the OUTCOMEREA network. We developed a propensity score (PS) for adequate antimicrobial treatment, based on expert opinion of 45 attending physicians. We conducted a 1:1 case-cohort study matched on the PS score of being adequately treated. A PS-matched subdistribution hazard model was used for detecting subsequent infections and a PS-matched Cox model was used to evaluate the impact of antibiotic therapy on mortality. RESULTS: We included 427 patients with a catheter tip culture positive with potentially pathogenic microorganisms. We matched 150 patients with an adequate antimicrobial therapy with 150 controls. In the matched population, 30 (10%) subsequent infections were observed and 62 patients died within 30 days. Using subdistribution hazard models, the daily risk to develop subsequent infection up to Day-30 was similar between treated and non-treated groups (subdistribution hazard ratio [sHR] 1.08, 95% confidence interval [CI] 0.62-1.89, p = 0.78). Using Cox proportional hazard models, the 30-day mortality risk was similar between treated and non-treated groups (HR 0.89, 95% CI 0.45-1.74, p = 0.73). CONCLUSIONS: Antimicrobial therapy was not associated with decreased risk of subsequent infection or death in short-term catheter tip colonization in critically ill patients. Antibiotics may be unnecessary for positive catheter tip cultures.

Intravenous Fosfomycin as Adjunctive Therapy for Gram-Negative Bacteria Bloodstream Infections: a Propensity Score Adjusted Retrospective Cohort Study.

BACKGROUND: The role of intravenous fosfomycin (iv-FOS), as a part of combination therapy for Gram-negative bacteria bloodstream infections (GNB-BSI), needs to be evaluated in clinical practice as in vitro data show a potential efficacy. METHODS: All consecutive patients with a GNB-BSI from January 1st, 2021, to April 1st, 2023, were included. Primary outcome was 30-day mortality. A Cox- regression analysis was used to identify predictors of mortality. Moreover, an inverse-probability of treatment-weighting (IPTW) analysis was also performed. RESULTS: Overall, 363 patients were enrolled: 211 (58%) males, with a median (q1-q3) age of 68 (57-78) years, and a median Charlson-comorbidity index of 5 (3-7). At GNB-BSI onset, median SOFA score was 5 (2-7), 122 (34%) presented with septic shock. Pathogens involved were principally K. pneumoniae (42%), E. coli (28%), and P. aeruginosa (17%); of them 36% were carbapenem-resistant. The therapy included carbapenems (40%), cephalosporins (37%) and beta-lactams/beta-lactamases-inhibitors (19%); combination with iv-FOS was used in 98 (27%) cases at a median dosage of 16 (16-18) gr/daily. Use of iv-FOS was not associated with reduced crude mortality (21% vs 29%, p-value=0.147). However, at multivariable Cox-regression combination therapy with iv-FOS resulted protective for mortality (aHR=0.51, 95%CI=0.28-0.92), but not other combo-therapies (HR=0.69, 95%CI=0.44-1.16). This result was also confirmed at the IPTW-adjusted-Cox-model (aHR=0.52, 95%CI=0.31-0.91). Subgroup analysis suggested a benefit in severe infections (SOFA>6, PITT≥4) and when iv-FOS was initiated within 24 hours from GNB-BSI onset. CONCLUSIONS: Fosfomycin in combination therapy for GNB-BSI may have a role to improve survival. These results justify the development of further clinical trials.

Impact of care bundle audit on compliance to device care bundles and device associated infections in the Critical Care Unit of a tertiary care hospital, Southern India - A before-after interventional study.

BACKGROUND: A care bundle comprises a set of evidence-based practices in patient care that are grouped together with the assumption that these practices when performed together will result in better clinical outcomes than when these practices are performed separately. Care bundles for devices when implemented effectively can bring about a reduction in device associated infection rates. METHODS: The study was conducted in three phases, 1 month pre-interventional and interventional phases and 11 months of post-interventional phase in a critical care unit. Compliance to care bundles were recorded by direct observation during daily audit rounds. An educational intervention addressing the healthcare workers regarding bundle care approach was conducted and supplemented with bedside "audit and feedback" during the interventional phase. Audit was conducted in the post-interventional period to study the trend of device associated infections and compliance rates. RESULTS: An increasing trend of month-wise compliance rates to the device care bundles were observed. The month-wise Ventilator Associated Events rates showed a decreasing trend. In the post-interventional phase, the average Catheter-associated Urinary Tract Infection, Central Line Associated Bloodstream Infection and Ventilator Associated Events rates showed a reduction from their respective baseline rates for the study setting. CONCLUSIONS: An educational intervention targeted at the healthcare workers along with daily audit of care bundle practices in the critical care setting led to an increase in the compliance to device care bundles and a reduction in the incidence of Catheter-associated Urinary Tract Infection, Central Line Associated Bloodstream Infection and Ventilator Associated Events rates in the critical care setting.

Epidemiology of bloodstream infections caused by extended-spectrum cephalosporin-resistant Escherichia coli and Klebsiella pneumoniae in Switzerland, 2015-2022: secular trends and association with the COVID-19 pandemic.

BACKGROUND: The association between the COVID-19 pandemic and the incidence of invasive infections caused by multidrug-resistant organisms remains a topic of debate. AIM: To analyse the national incidence rates of bloodstream infections (BSI) caused by Escherichia coli (EC) and Klebsiella pneumoniae (KP) with extended-spectrum cephalosporin-resistance (ESCR) in two distinct regions in Switzerland, each exhibiting varying antimicrobial resistance patterns and that were impacted differently by the pandemic. METHODS: We analysed data of positive blood cultures prospectively collected by the nationwide surveillance system (ANRESIS) from January 1, 2015, to August 31, 2022. To explore the potential relationship between COVID-19 patient occupancy and ESCR incidence rates, we conducted an in-depth analysis over the two-year pandemic period from April 1, 2020, to March 30, 2022. We employed Quasi-Poisson and logistic regression analyses to investigate these associations. RESULTS: During the study period, a total of 40997 EC-BSI and 8537 KP-BSI episodes were collected and reported to ANRESIS by the participating hospitals. ESCR was observed in 11% (n=4313) of E. coli and 8% (n=664) of K. pneumoniae, respectively. A significant reduction in ESCR-EC BSI incidence occurred during the pandemic in the region with the highest COVID-19 incidence. Conversely, ESCR-KP BSI incidence initially fell considerably and then increased during the pandemic in both regions, however, this effect was not statistically significant. No association between hospital occupancy from COVID-19 patients and these trends was observed. CONCLUSION: In the early phase of the COVID-19 pandemic, a decrease in ESCR rates was observed, particularly in ESCR-EC BSI within the most heavily impacted region.

The antimicrobial effectiveness of chlorhexidine and chlorhexidine-silver sulfadiazine impregnated central venous catheters against the emerging fungal pathogen Candida auris.

BACKGROUND: Candida auris is an emerging multidrug-resistant fungus associated with catheter-related bloodstream infections (CRBSI). In-vitro efficacy of chlorhexidine (CHX) and CHX/silver sulfadiazine-impregnated (CHX-S) antimicrobial central venous catheters (CVCs) against C. auris was investigated. MATERIAL AND METHODS: Minimum inhibitory (MIC) and bactericidal (MBC) CHX concentrations were determined against nineteen C. auris isolates. To assess extraluminal efficacy, segments from CVCs impregnated externally (CHX-S1) and both externally and internally (CHX-S2) were plasma-conditioned for 1- and 6-days, and to assess intraluminal efficacy CHX-S2 CVCs were pre-conditioned with saline-lock for 6-days, followed by 24-hour C. auris inoculation and microbial adherence determination on impregnated and non-impregnated CVCs. RESULTS: CHX inhibited all C. auris isolates with MIC and MBC range of 8-128 µg/mL. C. auris adherence was reduced on CHX-S1 and CHX-S2 extraluminally by 100% on day-1, 86.96%-100% on day-7, and intraluminally on CHX-S2 by 56.86%-90.52% on day-7. DISCUSSION: CHX and CHX-S CVCs performance against C. auris observed in this study is consistent with antimicrobial benefits observed in prior pre-clinical and randomized controlled clinical studies. CONCLUSIONS: CHX showed strong inhibitory and cidal effects on C. auris. CHX-S CVCs proved highly efficacious against this pathogen under in vitro conditions. Additional studies, however, are required to confirm clinical benefit.

Effectiveness of nanoparticle-based antimicrobial agents in the prevention and treatment of Central Venous Catheter-Associated Bloodstream Infections.

BACKGROUND: In healthcare settings, Central Venous Catheter-Associated Bloodstream Infections (CVC-BSIs) present a serious problem since they raise morbidity, mortality, and medical expense rates. The management of these illnesses is made more challenging by the development of antimicrobiotic resistance. Nanotechnology has attracted interest recently as a viable method for creating new antimicrobial agents. By putting antibacterial nanomaterials onto the catheter's appear, that may reduce the likelihood of getting sick by stopping germs from adhering and growing. Antimicrobial additives can be released gradually finishes, protecting over time through bioengineering sectors. To prevent and treat CVC-BSIs, this study will assess the efficacy of antimicrobial medicines based on nanoparticles. METHODS: In the network Meta-Analyses (MA) and Systematic Review (SR), we looked for studies published from January 2010 to September 2021 using the Cochrane Central Register of Controlled Trials (CENTRAL), EMBASE, MEDLINE, CINAHL, and Web of Science databases. Ten papers in all were included in the review following the screening of the publications using inclusion and exclusion criteria. RESULTS: In contrast to conventional catheters, the implementation of Antimicrobial Catheters (AC) and the use of chlorhexidine (CHG) or Silver Sulfadiazine (SS) demonstrated notably reduced occurrences of Central Venous Catheter-Associated Bloodstream Infections (CVC-BSIs) per 1000 Catheter Days (CD) (with Odds Ratios (ORs) and 95% Credibility Intervals (CrIs) of 0.66 and 0.54, respectively) by bioengineering sectors. Moreover, these interventions were linked to the lowest rate of Catheter Colonization (CC), with ORs as well as 95% CrIs of 0.45 and 0.31, respectively, underscoring their potential as effective strategies for minimizing the risk of infections associated with catheter use as well as bioengineering sectors innovations. CONCLUSIONS: As a result, CVC-BSI has shown significant promise for prevention and treatment with nanoparticle-based antimicrobial medicines. Due to their special characteristics and modes of action, they are strong candidates for improving the security and effectiveness of central venous catheter use in clinical settings. Due to ongoing research and development in this area, nanoparticle-based coatings and therapies may be used to lessen the impact of CVC-BSIs and enhance patient outcomes.

Risk factors and clinical impact of multidrug resistance in healthcare-associated bacteremic urinary tract infections: a post-hoc analysis of a multicenter prospective cohort in Spain.

INTRODUCTION: The global burden associated with antimicrobial resistance is of increasing concern. The aim of this study was to evaluate risk factors associated with multidrug-resistant (MDR) infection and its clinical impact in a cohort of patients with healthcare-associated (HCA) bacteremic urinary tract infections (BUTI). METHODS: This is a post-hoc analysis a prospective multicenter study of patients with HCA-BUTI (ITUBRAS-2). The primary outcome was MDR profile. Secondary outcomes were clinical response (at 48-72h and at hospital discharge) and length of hospital stay from onset of BUTI. Logistic regression was used to evaluate variables associated with MDR profile and clinical response. Length of hospital stay was evaluated using multivariate median regression. RESULTS: 443 episodes were included, of which 271 (61.17%) were classified as expressing an MDR profile. In univariate analysis, MDR profile was associated with E. coli episodes (OR 3.13, 95% CI 2.11-4.69, p<0.001) and the extensively drug-resistant (XDR) pattern with P. aeruginosa etiology (OR 7.84, 95% CI 2.37-25.95; p=0.001). MDR was independently associated with prior use of fluoroquinolones (aOR 2.43; 95% CI 1.25-4.69), cephalosporins (aOR 2.14; 95% CI 1.35-3.41) and imipenem or meropenem (aOR 2.08; 95% CI 1.03-4.20) but not with prior ertapenem. In terms of outcomes, MDR profile was not associated with lower frequency of clinical cure, but with longer hospital stay. CONCLUSIONS: MDR profile was independently associated with prior use of fluoroquinolones, cephalosporins, imipenem and meropenem, but not with prior ertapenem. MDR-BUTI episodes were not associated with worse clinical cure, although was independently associated with longer duration of hospital stay.

Risk factors and crucial prognostic indicators of mortality in liver transplant recipients with bloodstream infections: A comprehensives study of 1049 consecutive liver transplants over an 11-year period.

BACKGROUND: Liver transplantation (LT) is a pivotal treatment for end-stage liver disease. However, bloodstream infections (BSI) in the post-operative period present a significant threat to patient survival. This study aims to identify risk factors for post-LT BSI and crucial prognostic indicators for mortality among affected patients. METHODS: We conducted a retrospective study of adults diagnosed with end-stage liver disease who underwent their initial LT between 2010 and 2021. Those who developed BSI post-LT during the same hospital admission were classified into the BSI group. RESULTS: In this cohort of 1049 patients, 89 (8.4%) developed BSI post-LT, while 960 (91.5%) did not contract any infection. Among the BSI cases, 17 (19.1%) patients died. The average time to BSI onset was 48 days, with 46% occurring within the first month post-LT. Of the 123 isolated microorganisms, 97 (78.8%) were gram-negative bacteria. BSI patients had significantly longer stays in the intensive care unit and hospital compared to non-infected patients. The 90-day and in-hospital mortality rates for recipients with BSI were significantly higher than those without infections. Multivariate analysis indicated heightened BSI risk in patients with blood loss >3000 mL during LT (odds ratio [OR] 2.128), re-operation within 30 days (OR 2.341), post-LT bile leakage (OR 3.536), and graft rejection (OR 2.194). Additionally, chronic kidney disease (OR 6.288), each 1000 mL increase in intraoperative blood loss (OR 1.147) significantly raised mortality risk in BSI patients, whereas each 0.1 mg/dL increase in albumin levels correlated with a lower risk of death from BSI (OR 0.810). CONCLUSIONS: This study underscores the need for careful monitoring and management in the post-LT period, especially for patients at higher risk of BSI. It also suggests that serum albumin levels could serve as a valuable prognostic indicator for outcomes in LT recipients experiencing BSI.

The Molecular Mouse System: A New Useful Tool for Guiding Antimicrobial Therapy in Critically Ill Septic Patients.

Bloodstream infections (BSI) caused by multidrug-resistant (MDR) bacteria, pose a major threat for patients, especially for those who are immunosuppressed. Rapid pathogen detection and characterization from positive blood cultures are crucial in the management of patients with BSI to enable an adequate and timely antimicrobial therapy. This study aimed to investigate the potential role of the Molecular Mouse system, a new CE IVD molecular test designed to rapidly detect the causative agents of bacteremia and their resistance determinants, in the management of the therapy in critically ill patients. Agreement between the results of the Molecular Mouse and the conventional routine method was also considered. Overall, 100 positive blood cultures were collected from septic critically ill patients from May 2023 to January 2024 and analyzed with Molecular Mouse and routine protocols. The new instrument consistently agreed with the routine protocols in the case of monomicrobial blood cultures, while some discrepancies were obtained in the polymicrobial samples. Antimicrobial resistance genes were detected in 35 samples, with vanA and CTX-M-1/9 groups being the most frequently detected targets. Therapy was adjusted in 42 critically ill patients confirming the importance of new rapid molecular tests in the management of positive blood cultures, to adjust empirical therapy and use new antibiotics accurately.

Genomic investigation and clinical correlates of the in vitro ß-lactam: NaHCO3 responsiveness phenotype among methicillin-resistant Staphylococcus aureus isolates from a randomized clinical trial.

NaHCO3 responsiveness is a novel phenotype where some methicillin-resistant Staphylococcus aureus (MRSA) isolates exhibit significantly lower minimal inhibitory concentrations (MIC) to oxacillin and/or cefazolin in the presence of NaHCO3. NaHCO3 responsiveness correlated with treatment response to ß-lactams in an endocarditis animal model. We investigated whether treatment of NaHCO3-responsive strains with ß-lactams was associated with faster clearance of bacteremia. The CAMERA2 trial (Combination Antibiotics for Methicillin-Resistant Staphylococcus aureus) randomly assigned participants with MRSA bloodstream infections to standard therapy, or to standard therapy plus an anti-staphylococcal ß-lactam (combination therapy). For 117 CAMERA2 MRSA isolates, we determined by broth microdilution the MIC of cefazolin and oxacillin, with and without 44 mM of NaHCO3. Isolates exhibiting ≥4-fold decrease in the MIC to cefazolin or oxacillin in the presence of NaHCO3 were considered "NaHCO3-responsive" to that agent. We compared the rate of persistent bacteremia among participants who had infections caused by NaHCO3-responsive and non-responsive strains, and that were assigned to combination treatment with a ß-lactam. Thirty-one percent (36/117) and 25% (21/85) of MRSA isolates were NaHCO3-responsive to cefazolin and oxacillin, respectively. The NaHCO3-responsive phenotype was significantly associated with sequence type 93, SCCmec type IVa, and mecA alleles with substitutions in positions -7 and -38 in the regulatory region. Among participants treated with a ß-lactam, there was no association between the NaHCO3-responsive phenotype and persistent bacteremia (cefazolin, P = 0.82; oxacillin, P = 0.81). In patients from a randomized clinical trial with MRSA bloodstream infection, isolates with an in vitro ß-lactam-NaHCO3-responsive phenotype were associated with distinctive genetic signatures, but not with a shorter duration of bacteremia among those treated with a ß-lactam.

Risk analysis of candidemia and its effect on mortality in COVID 19 and non COVID 19 patients.

Background and Objectives: Candidemia is the most common serious fungal infection in critically ill patients in intensive care units (ICU). It series fourth among bloodstream infectious agents. In this study, candidemia risk analysis was examined in COVID 19 and non-COVID 19 patients during the pandemic period. Materials and Methods: COVID 19 and non-COVID 19 cases who were followed up with candidemia in the ICU of our hospital were retrospectively screened. Demographic data, intubation, central venous catheter (CVC), medications, and total parenteral nutrition (TPN) status were evaluated in terms of risk between the two groups. Isolated Candida species and susceptibilty were evaluated. Results: When age, gender, medication, intubation, TPN and CVC were evaluated, no difference was seen in terms of risk. Differences were detected in terms of comorbidities. While the most frequently identified Candida species was C. albicans, the most frequently detected species in the COVID19 patient group was C. parapsilosis. Conclusion: There was no difference in candidemia incidence and risk factors between the two groups. Since candidemias were evaluated in terms of comorbidities, it was determined that Diabetes Mellitus (DM) and chronic obstructive pulmoner disease (COPD) were more common in patients with COVID 19 and less common in coronary artery disease (CAD) and malignancy.