Onset Of Bloodstream Infection Research Articles

Impact of a Multistep Bundles Intervention in the Management and Outcome of Gram-Negative Bloodstream Infections: A Single-Center "Proof-of-Concept" Study.

BackgroundThis is a “proof-of-concept” study aiming to evaluate the impact of a multistep bundles intervention in the management and outcomes of patients with gram-negative bloodstream infections (GN-BSIs).MethodsThis was a single-center, quasi-experimental design study. In the pre-phase (January 2019 to May 2020), patients were retrospectively enrolled. During the post-phase (June 2020 to September 2021), all patients were prospectively enrolled in a nonmandatory 3-step bundles intervention arm including (i) step 1: imaging to detect deep foci of infection, follow-up blood cultures and procalcitonin monitoring; (ii) step 2: early targeted antibiotic treatment and surgical source control; (iii) step 3: discontinuation of antibiotics within 7–10 days in case of uncomplicated BSI. Patients were followed up to 28 days from BSI onset. The primary outcome was 28-day mortality.ResultsA total of 271 patients were enrolled: 127 and 144 in the pre- vs post-phase, respectively. Full application of step 1 (67% vs 42%; P < .001), step 2 (83% vs 72%; P = .031), and step 3 (54% vs 2%; P < .001) increased in the post-phase. Overall, the intervention reduced 28-day mortality (22% vs 35%, respectively; P = .016) and the median duration of total (11 vs 15 days; P < .001) and targeted (8 vs 12 days; P = .001) antibiotic therapy. Finally, the multivariate Cox regression confirmed the independent protective effect of adherence to step 1 (adjusted hazard ratio [aHR], 0.36; 95% CI, 0.20–0.63) and step 2 (aHR, 0.48; 95% CI, 0.29–0.81) on risk of 28-day mortality.ConclusionsClinical management and outcomes of patients with GN-BSIs may be improved by providing a pre-established multistep bundles intervention.

Association Between Time to Appropriate Antimicrobial Treatment and 30-day Mortality in Patients With Bloodstream Infections: A Retrospective Cohort Study.

Effective antimicrobial treatment is key for survival in bloodstream infection (BSI), but the impact of timing of treatment remains unclear. Our aim was to assess the association between time to appropriate antimicrobial treatment and 30-day mortality in BSI patients. This was a retrospective cohort study using electronic health record data from a large academic center in Sweden. Adult patients admitted between the years 2012 and 2019, with onset of BSI at the emergency department or general wards, were included. Pathogen-antimicrobial drug combinations were classified as appropriate or inappropriate based on reported in vitro susceptibilities. To avoid immortal time bias, the association between appropriate therapy and mortality was assessed with multivariable logistic regression analysis at pre-specified landmark times. We included 10 628 BSI-episodes, occurring in 9192 unique patients. The overall 30-day mortality was 11.8%. No association in favor of a protective effect between appropriate therapy and mortality was found at the 1, 3 and 6 hours landmark after blood culture collection. At 12 hours, the risk of death increased with inappropriate treatment (adjusted odds ratio 1.17 [95% confidence interval {CI}, 1.01-1.37]) and continued to increase gradually at 24, 48, and 72 hours. Stratifying by high or low SOFA score generated similar odds ratios, with wider confidence intervals. Delays in appropriate antimicrobial treatment were associated with increased 30-day mortality after 12 hours from blood culture collection, but not at 1, 3, and 6 hours, in BSI. These results indicate a benchmark for providing rapid microbiological diagnostics of blood cultures.

Predictive Value of a Quick Pitt Bacteremia Score for Prognosis of Patients with Bloodstream Infection Secondary to Urinary Tract Infection: A Retrospective Cohort Study.

PurposeTo analyze the effect of a quick Pitt bacteremia score (qpitt) on the prognosis of patients with bloodstream infection (BSI) secondary to urinary tract infection (UTI) and to further explore its use in aiding appropriate selection of initial antibiotic treatment.MethodsMedical records of patients with BSIs secondary to UTIs who were admitted to our hospital from January 2018 to December 2020 were retrospectively collected. To screen for independent risk factors, logistic analysis was conducted on statistically significant variables. The receiver operating characteristic (ROC) curve was drawn with prognosis and death as the state variables to evaluate the predictive value. Patients were grouped by qpitt 2-point cutoff, to explore the impact of initial antimicrobial treatment regimens on poor prognosis and death in different subgroups. Poor prognosis was defined as a hospital length of stay (HLOS) ≥14 days or death within 28 days from BSI onset (ie, 28-day death).ResultsA total of 266 patients were included in this study. In BSIs secondary to UTIs, we observed a pathogenic composition of 77.44% Gram-negative bacteria, 19.55% Gram-positive bacteria, and 3.01% fungi. The qpitt had poor predictive value for poor prognosis [area under ROC (AUROC) = 0.653, p < 0.001], while it had a high predictive value for death (AUROC = 0.890, p < 0.001). For patients with a qpitt ≥2, the poor prognosis and death rates of patients who were initially treated with carbapenem antibiotics were lower (p < 0.01). In comparison, initial treatment with carbapenem antibiotics had no significant effect on prognosis and death rates in patients with qpitt <2 (p > 0.1).ConclusionThe qpitt is highly predictive for death in patients with BSIs secondary to UTIs and can be used to inform first-line antibiotic treatment strategy.

Clinical Impact of COVID-19 on Multi-Drug-Resistant Gram-Negative Bacilli Bloodstream Infections in an Intensive Care Unit Setting: Two Pandemics Compared.

Two mutually related pandemics are ongoing worldwide: the COVID-19 and antimicrobial resistance pandemics. This study aims to evaluate the impact of COVID-19 on multi-drug-resistant Gram-negative bacteria (MDR-GN) bloodstream infections (BSIs) in a single intensive care unit (ICU). We conducted a retrospective study including patients admitted to the ICU, reorganized for COVID-19 patients’ healthcare, with at least one confirmed MDR-GN BSI during 2019–2020. We compared clinical and microbiological features, incidence density, antibiotic therapy and mortality rate in pre- and during-COVID-19 pandemic periods. We estimated the impact of COVID-19 on mortality by means of univariate Cox regression analyses. A total of 46 patients were included in the study (28 non-COVID-19/18 COVID-19). Overall, 63 BSI episodes occurred (44/19), and non-COVID-19 patients had a higher incidence of MDR-GN BSIs and were more likely to present K. pneumoniae BSIs, while the COVID-19 group showed more A. baumannii BSIs with higher per pathogen incidence. COVID-19 patients presented more critical conditions at the BSI onset, a shorter hospitalization time from BSI to death and higher 30-day mortality rate from BSI onset. COVID-19 and septic shock were associated with 30-day mortality from MDR-GN BSIs, while early active therapy was a protective factor. In conclusion, COVID-19 showed a negative impact on patients with MDR-GN BSIs admitted to the ICU.

A prediction model for bacteremia and transfer to intensive care in pediatric and adolescent cancer patients with febrile neutropenia.

Febrile neutropenia (FN) is a common condition in children receiving chemotherapy. Our goal in this study was to develop a model for predicting blood stream infection (BSI) and transfer to intensive care (TIC) at time of presentation in pediatric cancer patients with FN. We conducted an observational cohort analysis of pediatric and adolescent cancer patients younger than 24 years admitted for fever and chemotherapy-induced neutropenia over a 7-year period. We excluded stem cell transplant recipients who developed FN after transplant and febrile non-neutropenic episodes. The primary outcome was onset of BSI, as determined by positive blood culture within 7 days of onset of FN. The secondary outcome was transfer to intensive care (TIC) within 14 days of FN onset. Predictor variables include demographics, clinical, and laboratory measures on initial presentation for FN. Data were divided into independent derivation (2009–2014) and prospective validation (2015–2016) cohorts. Prediction models were built for both outcomes using logistic regression and random forest and compared with Hakim model. Performance was assessed using area under the receiver operating characteristic curve (AUC) metrics. A total of 505 FN episodes (FNEs) were identified in 230 patients. BSI was diagnosed in 106 (21%) and TIC occurred in 56 (10.6%) episodes. The most common oncologic diagnosis with FN was acute lymphoblastic leukemia (ALL), and the highest rate of BSI was in patients with AML. Patients who had BSI had higher maximum temperature, higher rates of prior BSI and higher incidence of hypotension at time of presentation compared with patients who did not have BSI. FN patients who were transferred to the intensive care (TIC) had higher temperature and higher incidence of hypotension at presentation compared to FN patients who didn’t have TIC. We compared 3 models: (1) random forest (2) logistic regression and (3) Hakim model. The areas under the curve for BSI prediction were (0.79, 0.65, and 0.64, P < 0.05) for models 1, 2, and 3, respectively. And for TIC prediction were (0.88, 0.76, and 0.65, P < 0.05) respectively. The random forest model demonstrated higher accuracy in predicting BSI and TIC and showed a negative predictive value (NPV) of 0.91 and 0.97 for BSI and TIC respectively at the best cutoff point as determined by Youden’s Index. Likelihood ratios (LRs) (post-test probability) for RF model have potential utility of identifying low risk for BSI and TIC (0.24 and 0.12) and high-risk patients (3.5 and 6.8) respectively. Our prediction model has a very good diagnostic performance in clinical practices for both BSI and TIC in FN patients at the time of presentation. The model can be used to identify a group of individuals at low risk for BSI who may benefit from early discharge and reduced length of stay, also it can identify FN patients at high risk of complications who might benefit from more intensive therapies at presentation.

Clinical characteristics and risk factors of Aeromonas bloodstream infections in patients with hematological diseases

BackgroundTo analyze the clinical features, risk factors and outcomes of Aeromonas bloodstream infections (BSIs) in patients with hematological diseases to establish an effective optimal therapy against it.MethodsA retrospective study was performed by reviewing medical records of patients admitted to a tertiary blood disease hospital in China. Patients with hematological diseases who suffered from Aeromonas bacteremia during January 2002 to December 2020 were enrolled in this study.ResultsA total of 63 patients who developed Aeromonas bacteremia were enrolled in the study, and 91.9% of patients were neutropenic at the onset of BSIs. The major complications were skin and soft tissue infection (SSTI) (22.2%), followed by gastroenteritis (19.0%) and pneumonia (14.3%). High carbapenem resistance rates (70.8% for imipenem, 71.4% for meropenem) were note among the cases. Furthermore, Aeromonas strains isolated from five individuals developed resistance to quinolone, β-lactams and tigecycline during the therapy. The 30-day mortality rate was 15.9%, while bacteremia with SSTI showed a much worse prognosis, with 50.0% (7/14) of the patients dying within 30 days of initiating the therapy. In the multivariate analysis, SSTI (OR = 28.72; 95% CI, 1.50–551.30; P = 0.026) and shock (OR = 47.58; 95% CI,1.06–2126.80; P = 0.046) were independent risk factors for mortality.ConclusionsAeromonas bacteremia usually occurred in patients with neutropenic status, and patients with SSTIs were more likely to show a worse prognosis. Carbapenems should be avoided in patients with Aeromonas BSIs and SSTIs given high resistance rate.

The Value of Neutrophil-To-Lymphocyte Ratio for Evaluating Blood Stream Infection Caused by Carbapenem-Resistant Klebsiella pneumoniae: A Retrospective Cohort Study.

BackgroundThe neutrophil-to-lymphocyte ratio (NLR) is a useful marker of inflammation. However, the prognostic function of the NLR in patients with carbapenem-resistant Klebsiella pneumoniae (CRKP) blood stream infection (BSI) remains largely unknown. The aim of this study was to explore the potential relationship between the NLR and mortality in these patients.MethodsWe performed a retrospective cohort study based on data retrieved from the computerized patient record system in a tertiary hospital from 1 January 2017 to 31 October, 2020. A total of 134 inpatients with CRKP BSI were enrolled in this study, including 54 fatal cases and 80 survival cases, 28 days after the onset of CRKP BSI. A logistic analysis was performed to assess the association between the NLR on the 4th day and 28-day mortality. Multivariate analyses were used to control for the confounders.ResultsThe overall 28-day mortality rate of patients with a CRKP BSI episode was 40.3% (54/134). We conducted a multivariate analysis of the data of 134 patients and found that the NLR on the 4th day [odds ratio (OR) 1.148, 95% confidence interval (CI) 1.076–1.225, p < 0.001] and antibiotic exposure before BSI onset (OR 3.847, 95% CI 1.322–11.196, p = 0.013) were independent risk factors for 28-day mortality of patients with CRKP BSI, while appropriate initial therapy (AIT, OR 0.073, 95% CI 0.017–0.307, p < 0.001) was an independent protective factor. Among patients treated with AITs, the Cox proportional hazards regression analysis revealed a significant difference in prognosis (p = 0.006) between the ceftazidime/avibactam contained (CAZ) group and non CAZ-AVI groups. After dividing the non CAZ-AVI group into the tigecycline (TGC), colistin (COL), and TGC + COL groups, there were no differences between the CAZ-AVI group and the TGC group (p = 0.093), but CAZ-AVI group showed lower 28-day mortality than COL (p = 0.002) and TGC + COL (p = 0.002) groups. Meanwhile, there was no difference in NLR on the 1st day (p = 0.958) of patients in different groups but significant difference in NLR on the 4th day (p = 0.047).ConclusionsThe NLR on the 4th day is a readily available and independent prognostic biomarker for patients with CRKP BSI. This marker may have the potential for use in evaluating the efficacy of different anti-infection therapy strategies at an early stage.

A retrospective observational cohort study of the clinical epidemiology of bloodstream infections due to carbapenem-resistant Klebsiella pneumoniae in an OXA-48 endemic setting

This study aimed to characterize the epidemiology and clinical outcomes of patients with bloodstream infections (BSIs) due to carbapenem-resistant Klebsiella pneumoniae (CRKP) in an OXA-48-predominant environment. This was a retrospective single-centre cohort study including all consecutive patients with CRKP BSIs treated between 1 January 2014 and 31 December 2018. Multivariate analysis, subgroup analysis and propensity-score-matched analysis were employed to analyse 30-day mortality as the primary outcome. Clinical cure at day 14 was also analysed for the whole cohort. In total, 124 patients with unique isolates met all the inclusion criteria. OXA-48 was the most common type of carbapenemase (85.5%). Inappropriate therapy was significantly associated with 30-day mortality [70.6% vs 39.7%, adjusted odds ratio (aOR) 4.65, 95% confidence interval (CI) 1.50-14.40, P=0.008] and 14-day clinical failure (78.5% vs 56.2%, aOR 3.14, 95% CI 1.09-9.02, P=0.033) in multivariate analyses. Among those treated appropriately, the 30-day mortality rates were similar in monotherapy and combination therapy arms (OR 2.85, 95% CI 0.68-11.95, P=0.15). INCREMENT CPE mortality score (aOR 1.16, 95% CI 1.01-1.33, P=0.029), sepsis at BSI onset (aOR 2.90, 95% CI 1.02-8.27, P=0.046), and inappropriate therapy (aOR 4.65, 95% CI 1.50-14.40, P=0.008) were identified as independent risk factors for 30-day mortality. Colistin resistance in CRKP had no significant impact on 30-day mortality. These results were also confirmed in all propensity-score-matched analyses and sensitivity analyses. Appropriate regimens were associated with better clinical outcomes than inappropriate therapies for BSIs with CRKP predominantly possessing OXA-48.

Impact of COVID-19 pandemic on hospital onset bloodstream infections (HOBSI) at a large health system

BackgroundThe COVID-19 pandemic has had a considerable impact leading to increases in health care-associated infections, particularly bloodstream infections (BSI). MethodsWe evaluated the impact of COVID-19 in 69 US hospitals on BSIs before and during the pandemic. Events associated with 5 pathogens (Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, and Candida sp.) were stratified by community onset (CO) if ≤ 3 days from admission or hospital onset (HO) if > 3 days after admission. We compared pre-pandemic CO and HO rates with pandemic periods and the rates of BSI for those with and without COVID-19. ResultsCOVID-19 patients were less likely to be admitted with COBSI compared to others (10.85 vs 22.35 per 10,000 patient days; P < .0001). There was a significant increase between pre-pandemic and pandemic HOBSI rates (2.78 vs 3.56 per 10,000 patient days; P < .0001). Also, COVID-19 infected patients were 3.5 times more likely to develop HOBSI compared to those without COVID-19 infection (9.64 vs 2.74 per 10,000 patient-days; P < .0001). ConclusionsThe COVID-19 pandemic period was associated with substantial increases in HOBSI and largely attributed to COVID-19 infected patients. Future research should evaluate whether such measures would be beneficial to incorporate in evaluating infection prevention trends.

223. The Value of Neutrophil to Lymphocyte Count Ratio for Predicting the Clinical Outcomes of Patients with Carbapenem-resistant Klebsiella pneumonia Blood Stream Infection

BackgroundThe neutrophil to lymphocyte count ratio (NLR) has been recognized as a useful marker of inflammation. But, the prognostic function of NLR in patients with Carbapenem-resistant Klebsiella pneumonia (CRKP) blood stream infection is still largely unknown. The aim of this study was to explore the relationship between postoperative NLR and mortality in those patients.MethodsWe performed a retrospective study based on the database from Computerized Patient Record System in Sir Run Run Shaw Hospital from 1/1/2017 to 31/10/2020. Logistic analysis was performed to assess the associations between NLR and 28-day mortality. Multivariate analyses were used to control for confounders.ResultsA total of 134 CRKP blood stream infection inpatients were included in this study, including 54 fatal cases and 80 survival cases on the 28-day after the onset of CRKP BSI, the overall 28-day mortality rate of patients with a CRKP BSI episode was 40.3% (54/134). We conducted a multivariate analysis on these 134 patients and found that APACHE II score on the 4th day (OR 1.379 95% CI 1.065- 1.785, p = 0.015), NLR on the 4th day (OR 1.134 95% CI 1.054- 1.221, p = 0.001) were significant risk factors for the 28-day mortality of CRKP BSI patientsConclusionElevated NLR was significantly associated with increased 28-day mortality as well as APACHE II score on the 4th day after first positive culture.NLR is promising to be a readily available and independent prognostic biomarker for patients with CRKP blood stream infection.Disclosures All Authors: No reported disclosures

Bloodstream Infection Following Cardiac Valve Repair: A Population-Based Study.

BackgroundThe aim of this study was to determine the incidence, epidemiology, and associated risk factors of bloodstream infection (BSI) in patients who had previously undergone cardiac valve repair.MethodsA population-based study that included 7 counties in southeastern Minnesota using the expanded Rochester Epidemiology Project (e-REP) for adults (≥18 years) who underwent valve repair between 1 January 2010 and 31 December 2018 was conducted. Electronic health records were screened for development of BSI and infective endocarditis (IE) from the date of valve repair through 30 July 2020. A 1:4 nested case-control analysis was performed to determine an association, if any, of male sex, Charlson comorbidity index (CCI), and county of residence with BSI.ResultsA total of 335 patients underwent valve repair, of whom 28 (8.3%) developed an index case of BSI, with 14 episodes occurring within 1 year of surgery. The median age of patients with BSI was 70 years, and 79% were male. The crude incidence of BSI was 1671 cases per 100000 person-years and Escherichia coli was the most common pathogen. Case-control analysis demonstrated a significant correlation between CCI and incidence of BSI (P < .001). Only 4 (14.3%) patients developed IE concurrent with the onset of BSI, and no patients developed IE subsequent to BSI.ConclusionsThe crude incidence of BSI following valve repair was higher in our e-REP cohort than previous population-based studies, and half of the BSI cases occurred within 1 year of surgery. Patients with a higher CCI at baseline were at increased risk of subsequent BSI.

The Impact of Bacterial Biofilms on End-Organ Disease and Mortality in Patients with Hematologic Malignancies Developing a Bloodstream Infection.

ABSTRACTBacterial bloodstream infection (BSI) represents a significant complication in hematologic patients. However, factors leading to BSI and progression to end-organ disease and death are understood only partially. The study analyzes host and microbial risk factors and assesses their impact on BSI development and mortality. A total of 96 patients with hematological malignancies and BSI were included in the study. Host-associated risk factors and all causes of mortality were analyzed by multivariable logistic regression at 30 days after BSI onset of the first neutropenic episode. The multidrug-resistant profile and biofilm production of bacterial isolates from primary BSI were included in the analysis. Median age was 60 years. The underlying diagnoses were acute leukemia (55%), lymphoma (31%), and myeloma (14%). A total of 96 bacterial isolates were isolated from BSIs. Escherichia coli was the most common isolate (29.2%). Multidrug-resistant bacteria caused 10.4% of bacteremia episodes. Weak biofilm producers (WBPs) were significantly (P < 0.0001) more abundant (72.2%) than strong biofilm producers (SBPs) (27.8%). Specifically, SBPs were 7.1% for E. coli, 93.7% for P. aeruginosa, 50% for K. pneumoniae, and 3.8% for coagulase-negative staphylococci. Mortality at day 30 was 8.3%, and all deaths were attributable to Gram-negative bacteria. About 22% of all BSIs were catheter-related BSIs (CRBSIs) and mostly caused by Gram-positive bacteria (79.0%). However, CRBSIs were not correlated with biofilm production levels (P = 0.75) and did not significantly impact the mortality rate (P = 0.62). Conversely, SBP bacteria were an independent risk factor (P = 0.018) for developing an end-organ disease. In addition, multivariate analysis indicated that SBPs (P = 0.013) and multidrug-resistant bacteria (P = 0.006) were independent risk factors associated with 30-day mortality. SBP and multidrug-resistant (MDR) bacteria caused a limited fraction of BSI in these patients. However, when present, SBPs raise the risk of end-organ disease and, together with an MDR phenotype, can independently and significantly concur at increasing the risk of death.IMPORTANCE Bacterial bloodstream infection (BSI) is a significant complication in hematologic patients and is associated with high mortality rates. Despite improvements in BSI management, factors leading to sepsis are understood only partially. This study analyzes the contribution of bacterial biofilm on BSI development and mortality in patients with hematological malignancies (HMs). In this work, weak biofilm producers (WBPs) were significantly more abundant than strong biofilm producers (SBPs). However, when present, SBP bacteria raised the risk of end-organ disease in HM patients developing a BSI. Besides, SBPs, together with a multidrug-resistant (MDR) phenotype, independently and significantly concur at increasing the risk of death in HM patients. The characterization of microbial biofilms may provide key information for the diagnosis and therapeutic management of BSI and may help develop novel strategies to either eradicate or control harmful microbial biofilms.

Bloodstream infections in the COVID-19 era: results from an Italian multi-centre study

BackgroundCorrelation between coronavirus disease 2019 (COVID-19) and superinfections has been investigated, but remains to be fully assessed. This multi-centre study reports the impact of the pandemic on bloodstream infections (BSIs).MethodsThis study included all patients with BSIs admitted to four Italian hospitals between 1 January and 30 June 2020. Clinical, demographic and microbiologic data were compared with data for patients hospitalized during the same period in 2019.ResultsAmong 26,012 patients admitted between 1 January and 30 June 2020, 1182 had COVID-19. Among the patients with COVID-19, 107 BSIs were observed, with an incidence rate of 8.19 episodes per 1000 patient-days. The incidence of BSI was significantly higher in these patients compared with patients without COVID-19 (2.72/1000 patient-days) and patients admitted in 2019 (2.76/1000 patient-days). In comparison with patients without COVID-19, BSI onset in patients with COVID-19 was delayed during the course of hospitalization (16.0 vs 5 days, respectively). Thirty-day mortality among patients with COVID-19 was 40.2%, which was significantly higher compared with patients without COVID-19 (23.7%). BSIs in patients with COVID-19 were frequently caused by multi-drug-resistant pathogens, which were often centre-dependent.ConclusionsBSIs are a common secondary infection in patients with COVID-19, characterized by increased risk during hospitalization and potentially burdened with high mortality.

Epidemiology of clinically suspected and laboratory-confirmed bloodstream infections at a South African neonatal unit.

Data from Africa reporting the epidemiology of infection in hospitalised neonates are limited. A prospective study with convenience sampling was conducted to characterise neonates investigated with blood culture/s for suspected infection at a 132-bed neonatal unit in Cape Town, South Africa (1 February-31 October 2018). Enrolled neonates were classified as having proven bloodstream infection (BSI) (blood culture-positive with a pathogen) or presumed infection (clinically suspected but blood culture-negative) or as potentially at risk of infection (maternal risk factors at birth). Of 1299 hospitalised neonates with >1 blood culture sampling episode, 712 (55%) were enrolled: 126 (17.7%) had proven BSI; 299 (42%) had presumed infection and 287 (40.3%) were potentially at risk of infection. Neonates with proven BSI had lower birth weight and higher rates of co-existing surgical conditions versus the presumed/potential infection groups (p < 0.001). Median onset of proven BSI versus presumed infection was at 8 (IQR = 5-13) and 1 (IQR = 0-5) days respectively (p < 0.001). Most proven BSI were healthcare-associated (114/126; 90.5%), with Klebsiella pneumoniae (80.6% extended-spectrum β-lactamase producers) and Staphylococcus aureus (66.7% methicillin-resistant) predominating. Mortality from proven BSI (34/126; 27%) was substantially higher than that observed in presumed (8/299; 2.7%) and potential infections (3/287; 1.0%) (p < 0.001). The odds of death from proven BSI was 3-fold higher for Gram-negatives than for Gram-positive/fungal pathogens (OR = 3.23; 95% CI = 1.17-8.92). Proven BSI episodes were predominantly healthcare-associated and associated with a high case fatality rate. Most neonates with presumed infection or at potential risk of infection had favourable 30-day outcomes.

Epidemiology and outcomes of bloodstream infections in severe burn patients: a six-year retrospective study

BackgroundInfection is the leading cause of morbidity and mortality among burn patients, and bloodstream infection (BSI) is the most serious. This study aimed to evaluate the epidemiology and clinical outcomes of BSI in severe burn patients.MethodsClinical variables of all patients admitted with severe burns (≥ 20% total body surface area, %TBSA) were analyzed retrospectively from January 2013 to December 2018 at a teaching hospital. The Kaplan–Meier method was utilized for plotting survival curves. Multivariate logistic regression and Cox regression model were also performed.ResultsA total of 495 patients were evaluated, of whom 136 (27.5%) had a BSI. The median time from the patients being burned to BSI was 8 days. For BSI onset in these patients, 47.8% (65/136) occurred in the first week. The most frequently isolated causative organism was A. baumannii (22.7%), followed by methicillin-resistant Staphylococcus aureus (18.7%) and K. pneumoniae (18.2%), in patients with BSI. Multivariate logistic regression analysis showed that %TBSA (p = 0.023), mechanical ventilation (p = 0.019), central venous catheter (CVC) (p < 0.001) and hospital length of stay (27d vs 50d, p < 0.001) were independent risk factors associated with BSI. Cox regression model showed that acute kidney injury (HR, 12.26; 95% CI 2.31–64.98; p = 0.003) and septic shock (HR, 4.36; 95% CI 1.16–16.34; p = 0.031) were identified as independent predictors of 30-day mortality of BSI in burn patients.ConclusionsMultidrug resistant gram-negative bacteria were the main pathogens of BSI in severe burn patients. Accurate evaluation of risk factors for BSI and the mortality of BSI in severe burn patients may improve early appropriate management.

Bloodstream Infections in Preterm Neonates and Mortality-Associated Risk Factors

To investigate the association of early (±4hours after onset of bloodstream infection) clinical and laboratory variables with episode-related mortality (<7days). This 2-site retrospective study included 142 neonates born at <35weeks of gestational age with positive blood/cerebrospinal fluid (CSF) culture at >72hours of age from organisms other than coagulase-negative Staphylococcus. Early variables were compared between those with bloodstream infection-related mortality and survivors. Multivariable analysis was conducted for the primary outcome, and the area under the curve (AUC) was estimated for relevant variables. The neonates who died were of lower gestational age at disease onset. After adjusting for relevant variables, lowest mean blood pressure (MBP) (aOR, 0.10; 95% CI, 1.02-1.19) and highest base deficit (aOR, 1.18; 95% CI, 1.06-1.32) were independently associated with mortality. The AUC was 0.87 (95% CI, 0.78-0.96) for base deficit, increasing to 0.91 (95% CI, 0.83-0.99) with the addition of MBP. Low MBP and high base deficit within ±4hours of bloodstream infection onset identify preterm neonates at risk of mortality.

Clinical Profile, Prognostic Factors, and Outcome Prediction in Hospitalized Patients With Bloodstream Infection: Results From a 10-Year Prospective Multicenter Study.

Background: Bloodstream infection (BSI) is one of the most common serious bacterial infections worldwide and also a major contributor to in-hospital mortality. Determining the predictors of mortality is crucial for prevention and improving clinical prognosis in patients with nosocomial BSI.Methods: A nationwide prospective cohort study was conducted from 2007 until 2016 in 16 teaching hospitals across China. Microbiological results, clinical information, and patient outcomes were collected to investigate the pathogenic spectrum and mortality rate in patients with BSI and identify outcome predictors using multivariate regression, prediction model, and Kaplan–Meier analysis.Results: No significant change was observed in the causative pathogen distribution during the 10-year period and the overall in-hospital mortality was 12.83% (480/3,741). An increased trend was found in the mortality of patients infected with Pseudomonas aeruginosa or Acinetobacter baumannii, while a decreased mortality rate was noted in Staphylococcus aureus-related BSI. In multivariable-adjusted models, higher mortality rate was significantly associated with older age, cancer, sepsis diagnosis, ICU admission, and prolonged hospital stay prior to BSI onset, which were also determined using machine learning-based predictive model achieved by random forest algorithm with a satisfactory performance in outcome prediction.Conclusions: Our study described the clinical and microbiological characteristics and mortality predictive factors in patients with BSI. These informative predictors would inform clinical practice to adopt effective therapeutic strategies to improve patient outcomes.

Impact of the Inclusion of an Aminoglycoside to the Initial Empirical Antibiotic Therapy for Gram-Negative Bloodstream Infections in Hematological Neutropenic Patients: a Propensity-Matched Cohort Study (AMINOLACTAM Study).

To test the hypothesis that the addition of an aminoglycoside to a β-lactam antibiotic could provide better outcomes than β-lactam monotherapy for the initial empirical treatment of hematological neutropenic patients with subsequently documented Gram-negative bacillus (GNB) bloodstream infection (BSI), a multinational, retrospective, cohort study of GNB BSI episodes in hematological neutropenic patients in six centers (2010 to 2017) was conducted. Combination therapy (β-lactam plus aminoglycoside) was compared to β-lactam monotherapy. The primary endpoint was the case fatality rate, assessed at 7 and 30 days from BSI onset. Secondary endpoints were nephrotoxicity and persistent BSI. Propensity score (PS) matching was performed. Among 542 GNB BSI episodes, 304 (56%) were initially treated with combination therapy, with cefepime plus amikacin being most common (158/304 [52%]). Overall, Escherichia coli (273/304 [50.4%]) was the main etiological agent, followed by Pseudomonas aeruginosa, which predominated in the combination group (76/304 [25%] versus 28/238 [11.8%]; P < 0.001). Multidrug resistance rates were similar between groups (83/294 [28.2%] versus 63/233 [27%]; P = 0.95). In the multivariate analysis, combination therapy was associated with a lower 7-day case fatality rate (odds ratio [OR], 0.37; 95% CI, 0.14 to 0.91; P = 0.035) with a tendency toward lower mortality at 30 days (OR, 0.56; 95% CI, 0.29 to 1.08; P = 0.084). After PS matching, these differences remained for the 7-day case fatality rate (OR, 0.33; 95% CI, 0.13 to 0.82; P = 0.017). In addition, aminoglycoside use was not significantly associated with renal function impairment (OR, 1.12; 95% CI, 0.26 to 4.87; P = 0.9). The addition of an aminoglycoside to the initial empirical therapy regimen for febrile neutropenic hematological patients should be considered.

Risk Factors for Mortality in Adult COVID-19 Patients Who Develop Bloodstream Infections Mostly Caused by Antimicrobial-Resistant Organisms: Analysis at a Large Teaching Hospital in Italy

The aim of this study was to characterize COVID-19 (SARS-CoV-2-infected) patients who develop bloodstream infection (BSI) and to assess risk factors associated with in-hospital mortality. We conducted a retrospective observational study of adult patients admitted for ≥48 h to a large Central Italy hospital for COVID-19 (1 March to 31 May 2020) who had or had not survived at discharge. We included only patients having blood cultures drawn or other inclusion criteria satisfied. Kaplan–Meier survival or Cox regression analyses were performed of 293 COVID-19 patients studied, 46 patients (15.7%) had a hospital-acquired clinically relevant BSI secondary to SARS-CoV-2 infection, accounting for 58 episodes (49 monomicrobial and 9 polymicrobial) in total. Twelve episodes (20.7%) occurred at day 3 of hospital admission. Sixty-nine species were isolated, including Staphylococcus aureus (32.8%), Enterobacterales (20.7%), Enterococcus faecalis (17.2%), Candida (13.8%) and Pseudomonas aeruginosa (10.3%). Of 69 isolates, 27 (39.1%) were multidrug-resistant organisms. Twelve (54.5%) of 22 patients for whom empirical antimicrobial therapy was inappropriate were infected by a multidrug-resistant organism. Of 46 patients, 26 (56.5%) survived and 20 (43.5%) died. Exploring variables for association with in-hospital mortality identified > 75-year age (HR 2.97, 95% CI 1.15–7.68, p = 0.02), septic shock (HR 6.55, 95% CI 2.36–18.23, p < 0.001) and BSI onset ≤ 3 days (HR 4.68, 95% CI 1.40–15.63, p = 0.01) as risk factors independently associated with death. In our hospital, mortality among COVID-19 patients with BSI was high. While continued vigilance against these infections is essential, identification of risk factors for mortality may help to reduce fatal outcomes in patients with COVID-19.

Efficacy of β-lactam/β-lactamase inhibitors to treat extended-spectrum beta-lactamase-producing Enterobacterales bacteremia secondary to urinary tract infection in kidney transplant recipients (INCREMENT-SOT Project).

Whether active therapy with β-lactam/β-lactamase inhibitors (BLBLI) is as affective as carbapenems for extended-spectrum β-lactamase-producing Enterobacterales (ESBL-E) bloodstream infection (BSI) secondary to urinary tract infection (UTI) in kidney transplant recipients (KTRs) remains unclear. We retrospectively evaluated 306 KTR admitted to 30 centers from January 2014 to October 2016. Therapeutic failure (lack of cure or clinical improvement and/or death from any cause) at days 7 and 30 from ESBL-E BSI onset was the primary and secondary study outcomes, respectively. Therapeutic failure at days 7 and 30 occurred in 8.2% (25/306) and 13.4% (41/306) of patients. Hospital-acquired BSI (adjusted OR [aOR]: 4.10; 95% confidence interval [CI]: 1.50-11.20) and Pitt score (aOR: 1.47; 95% CI: 1.21-1.77) were independently associated with therapeutic failure at day 7. Age-adjusted Charlson Index (aOR: 1.25; 95% CI: 1.05-1.48), Pitt score (aOR: 1.72; 95% CI: 1.35-2.17), and lymphocyte count ≤500cells/μL at presentation (aOR: 3.16; 95% CI: 1.42-7.06) predicted therapeutic failure at day 30. Carbapenem monotherapy (68.6%, primarily meropenem) was the most frequent active therapy, followed by BLBLI monotherapy (10.8%, mostly piperacillin-tazobactam). Propensity score (PS)-adjusted models revealed no significant impact of the choice of active therapy (carbapenem-containing vs any other regimen, BLBLI- vs carbapenem-based monotherapy) within the first 72hours on any of the study outcomes. Our data suggest that active therapy based on BLBLI may be as effective as carbapenem-containing regimens for ESBL-E BSI secondary to UTI in the specific population of KTR. Potential residual confounding and unpowered sample size cannot be excluded (ClinicalTrials.gov identifier: NCT02852902).