Bloodstream Infections In Patients Research Articles

Strain Differences in Bloodstream and Skin Infection MRSA isolated between 2019-2021 in a Single Health System

Abstract S. aureus is a common cause of skin and soft tissue infections (SSTIs) and has recently become the most common cause of bloodstream infections (BSIs), but whether the strains causing these two clinical syndromes overlap has not been studied adequately. USA300/500 (clonal complex [CC] 8-ST8) and USA100 (CC5-ST5) have dominated among methicillin-resistant S. aureus (MRSA) strains in the U.S. since the early 2000s. We compared the genomes of unselected MRSA isolates from 131 SSTIs with those from 145 BSIs at a single U.S. center in overlapping periods in 2018-2021. CC8 MRSA was more common among SSTIs and CC5 was more common among BSIs, consistent with prior literature. Based on clustering genomes with a threshold of 15 single nucleotide polymorphisms (SNPs), we identified clusters limited to SSTI patients and separate clusters exclusively comprising BSI patients. However, we additionally identified eight clusters that included at least one SSTI and one BSI isolate. This suggests that virulent MRSA strains are transmitted from person-to-person locally in the healthcare setting or the community and that single lineages are often capable of causing both SSTIs and BSIs.

A machine learning model for the early diagnosis of bloodstream infection in patients admitted to the pediatric intensive care unit.

Bloodstream infection (BSI) is associated with increased morbidity and mortality in the pediatric intensive care unit (PICU) and high healthcare costs. Early detection and appropriate treatment of BSI may improve patient's outcome. Data on machine-learning models to predict BSI in pediatric patients are limited and neither study included time series data. We aimed to develop a machine learning model to predict an early diagnosis of BSI in patients admitted to the PICU. This was a retrospective cohort study of patients who had at least one positive blood culture result during stay at a PICU of a tertiary-care university hospital, from January 1st to December 31st 2019. Patients with positive blood culture results with growth of contaminants and those with incomplete data were excluded. Models were developed using demographic, clinical and laboratory data collected from the electronic medical record. Laboratory data (complete blood cell counts with differential and C-reactive protein) and vital signs (heart rate, respiratory rate, blood pressure, temperature, oxygen saturation) were obtained 72 hours before and on the day of blood culture collection. A total of 8816 data from 76 patients were processed by the models. The machine committee was the best-performing model, showing accuracy of 99.33%, precision of 98.89%, sensitivity of 100% and specificity of 98.46%. Hence, we developed a model using demographic, clinical and laboratory data collected on a routine basis that was able to detect BSI with excellent accuracy and precision, and high sensitivity and specificity. The inclusion of vital signs and laboratory data variation over time allowed the model to identify temporal changes that could be suggestive of the diagnosis of BSI. Our model might help the medical team in clinical-decision making by creating an alert in the electronic medical record, which may allow early antimicrobial initiation and better outcomes.

Clinical Characteristics, Prognosis and Treatment of Bloodstream Infections with Enterobacter Cloacae Complex in a Chinese Tertiary Hospital: A Retrospective Study.

This research aimed to analyze the clinical characteristics, prognosis, and antimicrobial treatment of bloodstream infections (BSI) caused by Enterobacter cloacae complex (ECC). The clinical data of patients with bloodstream infections caused by Enterobacter cloacae complex from April 2017 to June 2023 were collected retrospectively. These data were then analyzed in subgroups based on the detection results of extended-spectrum β-lactamase (ESBL), 30-day mortality, and the type of antimicrobial agent used (β-lactam/β-lactamase inhibitor combinations (BLICs) or carbapenems). The proportion of ESBL-producing Enterobacter cloacae complex was 32.5% (37/114). Meanwhile, ICU admission, receiving surgical treatment within 3 months, and biliary tract infection were identified as risk factors for ESBL-producing ECC-BSI. Additionally, immunocompromised status and Sequential Organ Failure Assessment (SOFA) score ≥ 6.0 were identified as independent risk factors of 30-day mortality in patients with ECC-BSI (n = 108). Further analysis in BSI patients caused by non-ESBL-producing ECC revealed that patients treated with BLICs (n = 45) had lower SOFA scores and lower incidence of hypoproteinemia and sepsis compared with patients treated with carbapenems (n = 20). Moreover, in non-ESBL-producing ECC-BSI patients, the univariate Cox regression analysis indicated a significantly lower 30-day mortality rate in patients treated with BLICs compared to those treated with carbapenems (hazard ratios (HR) [95% CI] 0.190 [0.055-0.662], P = 0.009; adjusted HR [95% CI] 0.106 [0.013-0.863], P = 0.036). This study investigated the factors influencing the susceptibility to infection by ESBL-producing strains and risk factors for 30-day mortality in ECC-BSI patients. The results revealed that ESBL-negative ECC-BSI patients treated with BLICs exhibited significantly lower 30-day mortality compared to those treated with carbapenems. BLICs were found to be more effective in ECC-BSI patients with milder disease (ESBL-negative and SOFA ≤6.0).

Serum GSDMD for Early Diagnosis of Bloodstream Infection and Differentiating Bacterial from Fungal Infections.

The role of Gasdermin D (GSDMD) in bloodstream infection (BSI) diagnosis is unknown. Serum GSDMD levels were measured in BSI patients. Endothelial cells and PBMCs were isolated, infected with bacteria/fungi, and intracellular/extracellular GSDMD concentrations were measured. An animal model was established to investigate the association between serum GSDMD levels and BSI incidence/progression. ROC curve analysis indicated that GSDMD could be a potential early diagnostic biomarker for BSI (AUC = 0.9885). Combining GSDMD with procalcitonin (PCT) improved the differential diagnosis of Gram-positive and Gram-negative bacteria (AUC = 0.6699, 66.15% specificity), and early diagnosis of Gram-positive bacteria (98.46% sensitivity), while PCT was not significantly elevated. The combined GSDMD and G-test had higher sensitivity (AUC = 0.7174) for differential diagnosis of bacterial and fungal infections, and early detection of fungal infections (98.44% sensitivity). In vitro and in vivo experiments confirmed that GSDMD levels increased significantly within 2 hours, peaked at 16 hours, and exhibited a time-dependent upward trend. Serum GSDMD, alone or combined with other biomarkers, has potential for early diagnosis and differential diagnosis of BSI caused by various pathogens. This finding offers a new strategy for early detection and treatment of BSI.

Bloodstream infection clusters for critically ill patients: analysis of two-center retrospective cohorts.

Bloodstream infections (BSI) are highly prevalent in hospitalized patients requiring intensive care. They are among the most serious infections and are highly associated with sepsis or septic shock, which can lead to prolonged hospital stays and high healthcare costs. This study aimed at establishing an easy-to-use nomogram for predicting the prognosis of patients with BSI. In retrospective study, records of patients with BSI admitted to the intensive care unit (ICU) over the period from Jan 1st 2016 to Dec 31st 2021 were included. We used data from two different China hospitals as development cohort and validation cohort respectively. The demographic and clinical data of patients were collected. Based on all baseline data, k-means algorithm was applied to discover the groups of BSI phenotypes with different prognostic outcomes, which was confirmed by Kaplan-Meier analysis and compared using log-rank tests. Univariate Cox regression analyses were used to estimate the risk of clusters. Random forest was used to identified discriminative predictors in clusters, which were utilized to construct nomogram based on multivariable logistic regression in the discovery cohort. For easy clinical applications, we developed a bloodstream infections clustering (BSIC) score according to the nomogram. The results were validated in the validation cohort over a similar period. A total of 360 patients in the discovery cohort and 310 patients in the validation cohort were included in statistical analyses. Based on baseline variables, two distinct clusters with differing prognostic outcomes were identified in the discovery cohort. Population in cluster 1 was 211 with a ICU mortality of 17.1%, while population in cluster 2 was 149 with an ICU mortality of 41.6% (p < 0.001). The survival analysis also revealed a higher risk of death for cluster 2 when compared with cluster 1 (hazard ratio: 2.31 [95% CI, 1.53 to 3.51], p < 0.001), which was confirmed in validation cohort. Four independent predictors (vasoconstrictor use before BSI, mechanical ventilation (MV) before BSI, Deep vein catheterization (DVC) before BSI, and antibiotic use before BSI) were identified and used to develop a nomogram. The nomogram and BSIC score showed good discrimination with AUC of 0.96. The developed score has potential applications in the identification of high-risk critically ill BSI patients.

Validation of a Stenotrophomonas maltophilia bloodstream infection prediction score in the hematologic malignancy population

Stenotrophomonas maltophilia (SM) bloodstream infections (BSIs) contribute to significant mortality in hematologic malignancy (HM) and hematopoietic stem cell transplantation (HSCT) patients. A risk score to predict SM BSI could reduce time to appropriate antimicrobial therapy (TTAT) and improve patient outcomes. A single center cohort study of hospitalized adults with HM/HSCT was conducted. Patients had ≥ 1 blood culture with a Gram-negative (GN) organism. A StenoSCORE was calculated for each patient. The StenoSCORE2 was developed using risk factors for SM BSI identified via logistic regression. Receiver operating characteristic (ROC) curves were plotted. Sensitivity and specificity for the StenoSCORE and StenoSCORE2 were calculated. Thirty-six SM patients and 534 non-SM patients were assessed. A StenoSCORE ≥ 33 points was 80% sensitive, 68% specific, and accurately classified 69% of GN BSIs. StenoSCORE2 variables included acute leukemia, prolonged neutropenia, mucositis, ICU admission, recent meropenem and/or cefepime exposure. The StenoSCORE2 performed better than the StenoSCORE (ROC AUC 0.84 vs. 0.77). A StenoSCORE2 ≥ 4 points was 86% sensitive, 76% specific, and accurately classified 77% of GN BSIs. TTAT was significantly longer for patients with SM BSI compared with non-SM BSI (45.16 h vs. 0.57 h; p < 0.0001). In-hospital and 28-day mortality were significantly higher for patients with SM BSI compared to non-SM BSI (58.3% vs. 18.5% and 66.7% vs. 26.4%; p-value < 0.0001). The StenoSCORE and StenoSCORE2 performed well in predicting SM BSIs in patients with HM/HSCT and GN BSI. Clinical studies evaluating whether StenoSCORE and/or StenoSCORE2 implementation improves TTAT and clinical outcomes are warranted.

Development and validation a nomogram prediction model for early diagnosis of bloodstream infections in the intensive care unit.

This study aims to develop and validate a nomogram for predicting the risk of bloodstream infections (BSI) in critically ill patients based on their admission status to the Intensive Care Unit (ICU). Patients' data were extracted from the Medical Information Mart for Intensive Care-IV (MIMIC-IV) database (training set), the Beijing Friendship Hospital (BFH) database (validation set) and the eICU Collaborative Research Database (eICU-CRD) (validation set). Univariate logistic regression analyses were used to analyze the influencing factors, and lasso regression was used to select the predictive factors. Model performance was assessed using area under receiver operating characteristic curve (AUROC) and Presented as a Nomogram. Various aspects of the established predictive nomogram were evaluated, including discrimination, calibration, and clinical utility. The model dataset consisted of 14930 patients (1444 BSI patients) from the MIMIC-IV database, divided into the training and internal validation datasets in a 7:3 ratio. The eICU dataset included 2100 patients (100 with BSI) as the eICU validation dataset, and the BFH dataset included 419 patients (21 with BSI) as the BFH validation dataset. The nomogram was constructed based on Glasgow Coma Scale (GCS), sepsis related organ failure assessment (SOFA) score, temperature, heart rate, respiratory rate, white blood cell (WBC), red width of distribution (RDW), renal replacement therapy and presence of liver disease on their admission status to the ICU. The AUROCs were 0.83 (CI 95%:0.81-0.84) in the training dataset, 0.88 (CI 95%:0.88-0.96) in the BFH validation dataset, and 0.75 (95%CI 0.70-0.79) in the eICU validation dataset. The clinical effect curve and decision curve showed that most areas of the decision curve of this model were greater than 0, indicating that this model has a certain clinical effectiveness. The nomogram developed in this study provides a valuable tool for clinicians and nurses to assess individual risk, enabling them to identify patients at a high risk of bloodstream infections in the ICU.

Reliability of Droplet Digital PCR Alone and in Combination with Interleukin-6 and Procalcitonin for Prognosis of Bloodstream Infection.

Bloodstream infection(BSI) is linked with high mortality, underscoring the significance of prompt etiological diagnosis for timely and precise treatment. This study aims to investigate the diagnostic value of droplet digital polymerase chain reaction(ddPCR) in combination with conventional inflammatory markers [interleukin-6(IL-6) and procalcitonin(PCT)] concerning disease progression and treatment prognosis in BSI patients. Furthermore, the study aims to explore a more efficient clinical application strategy. This prospective case seried study centers on 176 patients suspected of or confirmed with BSI. Blood samples were collected to extract nucleic acids for identifying pathogens (bacteria, fungi, and viruses) and determining copy loads via ddPCR. The sensitivity of ddPCR was markedly higher compared to the culture method (74.71% vs 31.03%). A positive correlation existed between bacterial load and levels of inflammatory markers [IL-6 (P=0.0182), PCT (P=0.0029), and CRP (P=0.0005)]. In suspected BSI cases, the combination of ddPCR and inflammatory markers could predict sepsis risk [ROC: Area under the curve(AUC)=0.6071, P=0.0383]. Within confirmed BSI patients, the ddPCR bacterial load of those with SOFA<7 was lower than that of the SOFA≥7 (P=0.0334). ddPCR (OR: 1.789, P=0.035) monitoring combined with PCT (OR: 1.787, P=0.035) holded predictive value for SOFA progression (AUC=0.7913, P=0.0003). Similarly, BSI survivors displayed a lower burden than non-survivors (P=0.0170). Additionally, ddPCR combinated with IL-6 provided a more accurate and expedited insight into clinical outcomes prediction for BSI confirmed patients (AUC=0.7352, P=0.0030). Serial monitoring of bacterial load by ddPCR effectively mirrored the clinical course of BSI in patients. Notably, patients with positive ddPCR virus infection exhibited significantly reduced lymphocyte counts (P=0.0003). In a clinical context, qualitative ddPCR results and quantitative continuous monitoring can more precisely assess sepsis progression and treatment prognosis in BSI patients. Furthermore, ddPCR results offer quicker and more accurate reference points for clinical antibacterial and antiviral interventions.

Bacteriological Profile and Antibiogram of Aerobic Blood Culture Isolates among Suspected Blood Stream Infections: A Cross-sectional Study

Introduction: Bloodstream Infections (BSIs) are important causes of morbidity and mortality worldwide. Blood culture is the most important diagnostic tool for BSI. The epidemiology and outcome of BSI are constantly changing due to increasing antimicrobial resistance, changing patterns of antibiotic drug usage, and the increased use of transient or permanent medical devices. Thus, regular monitoring of the bacterial aetiology of BSI and their antibiograms is necessary. Aim: To determine the bacteriological profile and antibiotic susceptibility patterns among suspected BSI patients. Materials and Methods: A hospital-based cross-sectional study was carried out in the Department of Microbiology, Jawaharlal Nehru Institute of Medical Sciences (JNIMS), Imphal, Manipur, India, from September 2018 to August 2020. A total of 481 suspected BSI patients were included in the study. The blood culture samples were collected under aseptic conditions and cultured for seven days. The isolates were identified using conventional biochemical tests, and the antibiotic susceptibility pattern was determined by the Kirby-Bauer disk diffusion method and the epsilometer test (E-test). Methicillin resistance among the staphylococcal isolates was detected using the cefoxitin disk diffusion method. Data analysis was performed using EpiInfoTM version 7.0, and the Chi-square test was used as a statistical test. Results: A total of 150 (31.2%) blood samples were culture positive out of the 481 samples processed from suspected BSI patients. The predominant isolates were gram-positive, accounting for 113/150 (75.3%), while gram-negatives accounted for 37/150 (24.7%). Staphylococcus aureus, Pseudomonas aeruginosa, and Coagulase Negative Staphylococci (CoNS) were the primary pathogens isolated. Methicillin resistance was detected in 59 (54.6%) of the staphylococcal isolates {52 (54.7%) were Methicillin Resistant S. aureus (MRSA), and out of the 13 CoNS isolates, 7 (53.9%) were Methicillin Resistant CoNS (MRCoNS)}. The most susceptible drugs for gram-positives were vancomycin and linezolid, while aminoglycosides and imipenem were the most susceptible drugs for gram-negatives. Conclusion: The study highlighted the prevalence and pattern of aerobic bacterial isolates in BSI cases at JNIMS Hospital, as well as, the antibiotic susceptibility patterns of the isolates. Regular epidemiological studies of BSIs, regarding the pathogens and their antibiotic susceptibility patterns, are necessary to guide clinicians in choosing appropriate empirical therapy and to update the hospital antibiotic policy from time to time. This promotes rational antibiotic use and reduces resistance among bacteria.

Rectal culture could predict carbapenem-resistant organism bloodstream infection and reduce the mortality in haematological patients: A retrospective cohort study

The objective is to explore the correlation between rectal swab culture and the overall 30-d survival of hematologic patients diagnosed with carbapenem-resistant organism (CRO) bloodstream infection. A total of 434 haematological patients who were complicated with Gram-negative bacilli (GNB) bloodstream infections (BSIs) caused by Gram-negative bacteria between January 2020 and December 2021 were included in our retrospective study. Based on their drug susceptibility results, we classified patients into CRO BSIs and non-CRO BSIs cases. Through group comparison, to uncover the correlation between the positive screening of rectal swabs and reducing the mortality of CRO BSI in patients with haematological diseases. Among the 434 cases of Gram-negative bacteria bloodstream infection, 96 were identified as carbapenem-resistant bloodstream infection, which consisted of 57 cases of carbapenem-resistant Klebsiella pneumoniae (CR-KP), 19 cases of carbapenem-resistant Pseudomonas aeruginosa (CR-PA), 11 cases of carbapenem-resistant Escherichia coli (CR-CO), 5 cases of carbapenem-resistant Acinetobacter baumannii (CR-AB), and 4 cases of other Enterobacteriaceae. Before the onset of CRO bloodstream infection, rectal swab cultures were conducted on 36 patients, and the positive result rate was 75.0% (27/36), with 20 cases of CR-KP, 6 cases of CR-CO, and one case of carbapenem-resistant Enterobacter cloacae. It was observed that the rectal and blood cultures had matching outcomes in 75.0% of cases. The mortality rate within 30 d for CRO BSIs was 53.1% (51/96), while for carbapenem-resistant Enterobacteriaceae (CRE) BSIs it was 62.5% (45/72). Univariate analysis showed that 30-d mortality was significantly reduced when there were positive rectal culture results preceding bloodstream infection (P < 0.001), as well as preemptive anti-infection treatment (P < 0.001). Multivariate analysis demonstrated that preemptive adjustment to an effective antibiotic regimen, guided by positive rectal culture results, had a significant effect on decreasing 30-d mortality following CRO BSIs (P= 0.002). Furthermore, for the management of CRE BSIs, antibiotic treatments utilising ceftazidime/avibactam (CAV/AVI) may be more beneficial compared to those that use tigecycline (TGC) or polymyxin (PMB). CRO BSI, especially CRE BSI, can be life-threatening for those with haematological diseases. Utilising rectal culture can effectively identify CRO strains with high sensitivity and specificity. Adjusting antibiotic treatment based on the preemptive positive rectal culture results may significantly decrease 30-d mortality rates for haematological patients with CRO BSIs.

2076. Intestinal colonization with multidrug-resistant organisms, horizontal transmission and risk for bloodstream infection

Abstract Background The association between rectal colonization and subsequent bloodstream infections (BSI) by multidrug-resistant organisms (MDROs) remains to be clarified. We aimed to investigate the relative risk of BSI in rectal carriers of MDROs and in the case of carbapenem-resistant Enterobacteriaceae (CRE), whether BSI was due to the patient’s own colonizing strain. Methods We retrospectively included all adult inpatients hospitalized from Jan 2019 to Dec 2022, in ICUs or medical wards of 3 Greek hospitals (Athens: “Attikon” Hospital, Piraeus: Tzaneio Hospital, Thessaloniki: AHEPA Hospital), who were screened for intestinal MDRO carriage at admission and weekly. Screening was performed by selective media and immunochromatography for the carbapenemase in CRE. Patients were followed up for BSI by the same colonizing organism; relative risk (95% CI) was estimated after adjustment for ICU hospitalization and age. MDROs included CRE, carbapenem-resistant Acinetobacter baumannii (CRAB), carbapenem-resistant Pseudomonas aeruginosa (CRPA) and vancomycin-resistant enterococci (VRE). The CRE-colonizers and BSI-pathogens were analyzed for carbapenemase type to identify potential similarities. Results Of 4,427 patients screened, 1,321 (29.8%) were colonized by CRE, 1,255 (28.3%) with CRAB, 252 (5.7%) with CRPA and 859 (27.9% of 3,082 patients tested) with VRE. Of those, 207 (15.7%), 247 (19.7%), 23 (9.1%) and 30 (3.5%) subsequently developed CRE-BSI, CRAB-BSI, CRPA-BSI and VRE-BSI, respectively. Intestinal CRE colonization was associated with 4-fold higher risk of subsequent CRE-BSI, after adjusted for ICU stay and age [RR (95%CI): 4.1 (3.2, 5.2)]. The respective relative risk (95%CI) for BSI in patients with colonization by CRAB, CRPA and VRE were 2.3 (1.9, 2.8), 8.2 (5.1, 13.4) and 2.1 (1.3, 3.4). To evaluate possible horizontal transmission, 286 paired CRE strains from 143 patients were analyzed; in 111 (77.6%), both colonizers and BSI pathogens belonged to the same bacterial species and carried the same carbapenemase type.Table 1:Rectal colonization with MDROs and the risk for BSI from the same pathogenTable 2:Carbapenemase types in rectal carriers of CRE who developed subsequent BSI with the same pathogen Conclusion Intestinal colonization by MDROs was associated with increased risk of BSI by the colonizing bacteria. Clinicians should evaluate this information for empiric treatment, while genome-wide data are needed to substantiate horizontal transmission. Disclosures All Authors: No reported disclosures

Impact of preoperative bloodstream infection on outcomes of pediatric liver transplant recipients treated for acute liver failure.

Acute liver failure (ALF) is a component of multisystem organ failure that causes severe liver dysfunction in patients without underlying chronic liver disease. The patients with ALF are prone to have infections, including bacteremia. However, studies of the infectious impact for post liver transplantation (LT) in pediatric ALF are limited. We aimed to evaluate our current practice for pediatric LT cases of ALF with preoperative bacteremia. The records of all patients under 18 years old undergoing LT for ALF in our center from November 2005 to December 2021 were collected. They were divided into two groups: those with a preoperative bloodstream infection (BSI) and those without (NBSI). We compared the preoperative status and also reviewed the details of the BSI group. Intraoperative course and postoperative outcomes were also compared. There were 19 BSI patients and 66 NBSI patients. One BSI case was detected on the day of LT. This patient had no changes in vital signs and general condition. After evaluation and therapeutic intervention by pediatric infectious disease specialists, LT was performed on the same day. Five cases developed septic shock at the time of detection of BSI. All BSI patients were in stable condition on the operation day with proper interventions. There were no significant differences in mortality and hospital stay between both groups. LT might be able to be performed for pediatric ALF even with positive blood cultures. In addition, appropriate therapeutic intervention by specialists and patient's stable condition before LT are essential.

Blood Stream Infections in COVID-19 Patients From a Tertiary Care Center in Lebanon: Causative Pathogens and Rates of Multi-Drug Resistant Organisms

ObjectiveTo report the microbiological profile of the pathogens implicated in blood stream infections (BSI) in hospitalized coronavirus disease 2019 (COVID-19) patients and to examine the risk factors associated with multidrug-resistant organisms (MDROs) causing BSI. Patients and MethodsBetween March 2020 and September 2021, 1647 patients were hospitalized with COVID-19 at the American University of Beirut. From 85 patients, 299 positive blood cultures were reported to the Infection Control and Prevention Program. The BSI was defined as 1 positive blood culture for bacterial or fungal pathogens. The following organisms were considered MDROs: methicillin-resistant Staphylococcus aureus, vancomycin-resistant Enterococcus spp, carbapenem-resistant Enterobacterales spp., carbapenem-resistant Pseudomonas aeruginosa, MDR Acinetobacter baumannii only susceptible to colistin or tigecycline, and Candida auris. ResultsWe identified 99 true positive BSI events. Gram-negative bacteria accounted for 38.4 %, followed by Gram-positive bacteria (37.4%), and fungi (24.2%). The most isolated species were Candida spp. (23%), 3 of which were C. auris, followed by Enterobacterales spp. (13%), Enterococcus spp. (12%), S. aureus (9%), P. aeruginosa (9%), and A. baumannii (3%). The MDROs represented 26% of the events. The overall mortality rate was 78%. The time to acquisition of BSI in patients with MDROs was significantly longer compared with that of non-MDROs (20.2 days vs 11.2 days). And there was a significantly shorter time from acquisition of BSI to mortality between MDROs and non-MDROs (1.5 vs 8.3 days). ConclusionRigorous infection prevention and control measures and antimicrobial stewardship are important to prevent antimicrobial resistance progression, especially in low-resource settings.

Epidemiology and clinical significance of persistent bacteremia in severely burned patients

BackgroundThe utility of follow-up blood cultures (FUBC) for gram-negative bloodstream infections (BSIs) are controversial due to low rates of positivity. However, recent studies suggest higher rates of positivity in critically ill patients. The utility of FUBC in gram-negative BSI in patients with severe burn injuries is unknown. MethodsPatients ≥ 18 years old admitted to the US Army Institute of Surgical Research Burn Center for combat-related thermal burns from 1/2003–6/2014 with a monomicrobial BSI were included. FUBC were defined as repeat cultures 1–5 days from index BSI. Persistent BSI (pBSI) was defined as isolation of the same organism from initial and FUBC. The primary endpoint was all-cause in-hospital mortality in patients with gram-negative pBSI. ResultsOf 126 patients meeting inclusion criteria with BSI, 53 (42%) had pBSI. Compared to patients without persistence, patients with pBSI had more severe burns with median total body surface area (TBSA) burns of 47% ([IQR 34–63] vs. 35.3% [IQR 23.3–56.6], p = 0.02), increased mortality (38 vs. 11%, p = 0.001) compared to those with non-persistent BSI. On multivariate analysis, pBSI was associated with an odds ratio for mortality of 5.3 [95% CI 1.8–15.8, p = 0.003). Amongst gram-negative pathogens, persistence rates were high and associated with increased mortality (41% vs. 11%, p = 0.001) compared to patients without pBSI. ConclusionIn this cohort of military patients with combat-related severe burns, pBSI was more common than in other hospitalized populations and associated with increased mortality. Given this high frequency of persistence in patients with burn injuries and associated mortality, FUBC are an important diagnostic and prognostic study in this population.

Dalbavancin utilization registry investigating value and effectiveness (DRIVE): Outcomes report on real-world use

ObjectivesDalbavancin has potent activity against Gram-positive pathogens, including methicillin-resistant Staphylococcus aureus, and is approved for treatment of acute bacterial skin and skin structure infections (ABSSSI). We describe real-world use of dalbavancin in patients with ABSSSI, bloodstream infection (BSI), bone and joint infection (BJI), or other infection (OI). MethodsDalbavancin Utilization Registry Investigating Value and Effectiveness (DRIVE) was a phase 4 observational, multicenter, retrospective study of the real-world use of dalbavancin in adults across the United States. Data collected March 2017 – November 2018, at hospitals, intensive care units, and outpatient parenteral antibiotic therapy units, included patient demographics, diagnosis, microbiology, antibiotic use, clinical outcome, and adverse events up to 60 days after the last dose of dalbavancin. Patients were treated entirely at the physicians’ discretion. All patients who received ≥ 1 dose of dalbavancin between February 2016 and the end of the data collection period were included in the safety population. Patients with clear clinical success or failure of dalbavancin treatment, according to definitions similar to those used in the dalbavancin phase 3 trials, were included in the evaluable population and the post-hoc analysis. ResultsThe safety population comprised 1168 patients treated at 31 healthcare sites. Median cumulative dalbavancin dose was 1500 mg for all infection categories, most commonly as 1 infusion; 36.9 % of BSI patients and 58.6 % of BJI patients received ≥ 2 infusions; most were treated as outpatients. Serious adverse drug reactions were reported in 0.7 % of patients overall. Clinical success was achieved in 747/815 (91.7 %) evaluable patients with ABSSSI (BSI, 43/48 [89.6 %]; BJI, 75/87 [86.2 %]; OI, 7/7 [100 %]). ConclusionsDalbavancin demonstrated high rates of real-world clinical success and safety when treating patients for suspected or confirmed Gram-positive infections.

Mortality, hospital length of stay, and recurrent bloodstream infections associated with extended-spectrum beta-lactamase-producing Escherichia coli in a low prevalence region: A 20-year population-based large cohort study

ObjectivesThis population-based study aimed to investigate the risk factors and effect of extended-spectrum beta-lactamase (ESBL) production on clinical outcomes in Escherichia coli bloodstream infection (BSI) patients. MethodsThe study population was defined as patients aged ≥15 years with E. coli BSI in Queensland, Australia, from 2000 to 2019. Outcomes were defined as 30-day case fatality, hospital length of stay (LOS), and recurrent E. coli BSI. ResultsA total of 27,796 E. coli BSIs were identified, of which 1112 (4.0%) were ESBL-producers. Patients with ESBL-Ec BSI were more frequently older, male, with comorbidity, recurrent E. coli BSI, and less likely with community-associated community-onset infections as compared to non-ESBL-Ec BSI patients. The standardized mortality rate of ESBL-Ec BSI increased 8-fold from 2000 to 2019 (1 to 8 per million residents) and case fatality was 12.8% (n = 142) at 30 days from positive blood culture. Patients with ESBL-Ec BSI were not at higher risk of 30-day case fatality (adjusted hazard ratio [HR] = 0.98, 95% CI: 0.83-1.17), but had higher risk of recurring episodes (adjusted subdistribution HR = 1.58, 95% CI: 1.29-1.92) and observed 14% longer LOS (adjusted incidence rate ratio = 1.14, 95% CI: 1.10-1.18) than non-ESBL-Ec BSI patients. ConclusionIn this large patient cohort, ESBL-Ec BSI did not increase case fatality risk but observed higher hospital LOS and recurrent E. coli BSI than non-ESBL-Ec BSI. Clinical resources are warranted to account for the higher morbidity risk associated with ESBL production and incidence.

Evaluation of Different Blood Culture Bottles for the Diagnosis of Bloodstream Infections in Patients with HIV.

Bloodstream infection (BSI) is a significant factor contributing to hospitalization and high mortality rates among human immunodeficiency virus(HIV)-positive patients. Therefore, the timely detection of this condition is of utmost importance. Blood culture is considered the gold standard for diagnosing BSIs. Currently, BD BACTEC™ Plus Aerobic/F culture bottles and the BD BACTEC™ Myco/F Lytic culture bottles can be used for blood culture. This study aimed to evaluate the efficacy of two different types of culture bottles in diagnosing BSIs in patients with HIV. A retrospective analysis was conducted on HIV-positive patients hospitalized in the Infection Department of Wenzhou Central Hospital between July 2019 and October 2021. A total of 246 pairs of blood samples were included, consisting of an aerobic culture vial and a Myco/F culture vial. Blood culture results and clinical diagnosis were utilized to identify the presence of BSI. Out of 246 cases, 84 cases had positive blood cultures. Fungal BSIs, particularly Talaromycesmarneffei BSIs, were the most prevalent among patients with HIV. The positive rate of Myco/F culture bottles (89.29%) was significantly higher compared with aerobic culture bottles (69.05%; P = 0.001). In the diagnosis of fungal BSIs, the positive rate of Myco/F culture bottles was 88.57%, which was significantly higher than that of aerobic culture bottles (72.86%; P = 0.018). The Myco/F culture bottle has more advantages in diagnosing Talaromyces marneffei BSIs (P=0.028).In addition, mycobacteria were exclusively detected in Myco/F culture bottles. Fungal BSIs are the predominant type of infections in HIV-positive patients. Myco/F culture bottles exhibit noteworthy attributes of high positive rate in diagnosing HIV combined with BSI. These advantages are conducive to obtaining accurate culture results and minimizing missed diagnoses.

Incidence and Outcomes of Bloodstream Infection After Arterial Aneurysm Repair: Findings From a Population-Based Study.

Limited research has focused on bloodstream infection (BSI) in patients with arterial grafts. This study aims to describe the incidence and outcomes of BSI after arterial aneurysm repair in a population-based cohort. The expanded Rochester Epidemiology Project (e-REP) was used to analyze aneurysm repairs in adults (aged ≥18 years) residing in 8 counties in southern Minnesota from January 2010 to December 2020. Electronic records were reviewed for the first episode of BSI following aneurysm repair. BSI patients were assessed for vascular graft infection (VGI) and followed for all-cause mortality. During the study, 643 patients had 706 aneurysm repairs: 416 endovascular repairs (EVARs) and 290 open surgical repairs (OSRs). Forty-two patients developed BSI during follow-up. The 5-year cumulative incidence of BSI was 4.7% (95% confidence interval [CI], 3.0%-6.4%), with rates of 4.0% (95% CI, 1.8%-6.2%) in the EVAR group and 5.8% (95% CI, 2.9%-8.6%) in the OSR group (P = .052). Thirty-nine (92.9%) BSI cases were monomicrobial, 33 of which were evaluated for VGI. VGI was diagnosed in 30.3% (10/33), accounting for 50.0% (8/16) of gram-positive BSI cases compared to 11.8% (2/17) of gram-negative BSI cases (P = .017). The 1-, 3-, and 5-year cumulative post-BSI all-cause mortality rates were 22.2% (95% CI, 8.3%-34.0%), 55.8% (95% CI, 32.1%-71.2%), and 76.8% (95% CI, 44.3%-90.3%), respectively. The incidence of BSI following aneurysm repair was overall low. VGI was more common with gram-positive compared to gram-negative BSI. All-cause mortality following BSI was high, which may be attributed to advanced age and significant comorbidities in our cohort.

Bloodstream infections in neutropenic and non-neutropenic patients with haematological malignancies: epidemiological trends and clinical outcomes in Queensland, Australia over the last 20 years

Knowledge of the epidemiology of bloodstream infection (BSI) in haematology patients is essential to guide patient management. We investigated the epidemiology of BSI in patients with haematological malignancies in Queensland over the last 20 years (2000–2019), including all episodes diagnosed by the state-wide microbiology service. We identified 7749 BSI in 5159 patients, 58% associated with neutropenia. Gram-negatives were the main causative pathogens (58.3%), more frequent in neutropenic than non-neutropenic patients (3308/5309, 62.3% vs 1932/3678, 52.5%, p < 0.001). Amongst 8987 isolates the most common were E.coli (15.4%) and Pseudomonas spp. (14.2%). Pseudomonas spp. (16.6% vs 10.7%, p < 0.001), Klebsiella spp. (11.6% vs 6.8%, p < 0.001), viridans-group streptococci (4.4% vs 1.2%, p < 0.001) and E.faecium (2.4% vs 0.9%, p < 0.001) were more common in neutropenic than non-neutropenic patients, while S.aureus was less common (5.9% vs 15.6%, p < 0.001). Several antimicrobial resistance rates increased over time and had higher prevalence in neutropenic than non-neutropenic patients, including ciprofloxacin-resistant E.coli (94/758, 12.4% vs 42/506, 8.3%, p = 0.021), trimethoprim-sulfamethoxazole-resistant E.coli (366/764, 47.9% vs 191/517, 36.9%, p < 0.001), penicillin-resistant streptococci (51/236, 21.6% vs 28/260, 10.8%, p < 0.001) and vancomycin-resistant enterococci (46/250, 18.4% vs 9/144, 6.3%, p < 0.001). Carbapenem-resistant Pseudomonas spp. (OR 7.32, 95%CI 2.78–19.32) and fungi, including yeasts and moulds (OR 3.33, 95%CI 2.02–5.48) were associated to the highest odds of 30-day case-fatality at a multivariable logistic regression analysis. Neutropenia was associated with survival (OR 0.66, 95%CI 0.55–0.78). Differences were observed in the BSI epidemiology according to neutropenic status, with an overall increase of resistance over time associated to adverse outcome.

Diagnostic efficiency of the FilmArray blood culture identification (BCID) panel: a systematic review and meta-analysis.

Introduction. The FilmArray blood culture identification panel (BCID) panel is a multiplex PCR assay with high sensitivity and specificity to identify the most common pathogens in bloodstream infections (BSIs).Hypothesis. We hypothesize that the BCID panel has good diagnostic performance for BSIs and can be popularized in clinical application.Aim: To provide summarized evidence for the diagnostic accuracy of the BCID panel for the identification of positive blood cultures.Methodology. We searched the MEDLINE, EMBASE and Cochrane databases through March 2021 and assessed the efficacy of the diagnostic test of the BCID panel. We performed a meta-analysis and calculated the summary sensitivity and specificity of the BCID panel. Systematic review protocols were registered in the International Prospective Register of Systematic Reviews (PROSPERO) (registration number CRD42021239176).Results. A total of 16 full-text articles were eligible for analysis. The overall sensitivities of the BCID panel on Gram-positive bacteria, Gram-negative bacteria and fungi were 97 % (95 % CI, 0.96-0.98), 100 % (95 % CI, 0.98-01.00) and 99 % (95 % CI, 0.87-1.00), respectively. The pooled diagnostic specificities were 99 % (95 % CI, 0.97-1.00), 100 % (95 % CI, 1.00-1.00) and 100 % (95 % CI, 1.00-1.00) for Gram-positive bacteria, Gram-negative bacteria and fungi, respectively.Conclusions. The BCID panel has high rule-in value for the early detection of BSI patients. The BCID panel can still provide valuable information for ruling out bacteremia or fungemia in populations with low pretest probability.