Resistance In Bloodstream Infections Research Articles

Rapid identification of bloodstream infection pathogens and drug resistance using Raman spectroscopy enhanced by convolutional neural networks

Bloodstream infections (BSIs) are a critical medical concern, characterized by elevated morbidity, mortality, extended hospital stays, substantial healthcare costs, and diagnostic challenges. The clinical outcomes for patients with BSI can be markedly improved through the prompt identification of the causative pathogens and their susceptibility to antibiotics and antimicrobial agents. Traditional BSI diagnosis via blood culture is often hindered by its lengthy incubation period and its limitations in detecting pathogenic bacteria and their resistance profiles. Surface-enhanced Raman scattering (SERS) has recently gained prominence as a rapid and effective technique for identifying pathogenic bacteria and assessing drug resistance. This method offers molecular fingerprinting with benefits such as rapidity, sensitivity, and non-destructiveness. The objective of this study was to integrate deep learning (DL) with SERS for the rapid identification of common pathogens and their resistance to drugs in BSIs. To assess the feasibility of combining DL with SERS for direct detection, erythrocyte lysis and differential centrifugation were employed to isolate bacteria from blood samples with positive blood cultures. A total of 12,046 and 11,968 SERS spectra were collected from the two methods using Raman spectroscopy and subsequently analyzed using DL algorithms. The findings reveal that convolutional neural networks (CNNs) exhibit considerable potential in identifying prevalent pathogens and their drug-resistant strains. The differential centrifugation technique outperformed erythrocyte lysis in bacterial isolation from blood, achieving a detection accuracy of 98.68% for pathogenic bacteria and an impressive 99.85% accuracy in identifying carbapenem-resistant Klebsiella pneumoniae. In summary, this research successfully developed an innovative approach by combining DL with SERS for the swift identification of pathogenic bacteria and their drug resistance in BSIs. This novel method holds the promise of significantly improving patient prognoses and optimizing healthcare efficiency. Its potential impact could be profound, potentially transforming the diagnostic and therapeutic landscape of BSIs.

Emerging trends in antimicrobial resistance in bloodstream infections: multicentric longitudinal study in India (2017–2022)

BackgroundAntimicrobial resistance (AMR) has escalated to pandemic levels, posing a significant global health threat. This study examines the patterns and trends of AMR in Bloodstream Infections (BSIs) across India, aiming to inform better surveillance and intervention strategies. MethodsSix-year data from 21 tertiary care centers in the Indian Council of Medical Research's AMR Surveillance Network (IAMRSN) were retrospectively analyzed to estimate cluster-robust trends in resistance. Time-series analysis was used to discern lead/lag relationships between antibiotic pairs and the directional influence of resistance in community and hospital-acquired BSIs(CA/HA BSIs). A data-driven Bayesian network ensemble averaged over 301 bootstrap samples was modelled to uncover systemic associations between AMR and Sustainable Development Goals (SDGs). FindingsOur findings indicate significant (p<0.001) monthly increases in Imipenem and Meropenem resistance for Klebsiella, E. coli, and Acinetobacter BSIs. Importantly, Carbapenem resistance in HA-BSIs preceded that in CA-BSIs for Klebsiella and Acinetobacter (p<0.05). At a national level, Cefotaxime resistance emerged as a potential early indicator for emerging Carbapenem resistance, proposing a novel surveillance marker. In Klebsiella BSIs, states with higher achievement of SDG3 goals showed lower Imipenem resistance. A model-based AMR scorecard is introduced for focused interventions and continuous monitoring. InterpretationThe identified spatiotemporal trends and drug resistance associations offer critical insights for AMR surveillance aligning with WHO GLASS standards.The escalation of carbapenem resistance in BSIs demands vigilant monitoring and may be crucial for achieving SDGs by 2030. Implementing the proposed framework for data-driven evidence can help nations achieve proactive AMR surveillance. FundingNo specific funding was received for this analysis.

Molecular rapid diagnostic testing for bloodstream infections: Nanopore targeted sequencing with pathogen-specific primers

Nanopore sequencing, known for real-time analysis, shows promise for rapid clinical infection diagnosis but lacks effective assays for bloodstream infections (BSIs). We prospectively assessed the performance of a novel nanopore targeted sequencing (NTS) assay in identifying pathogens and predicting antibiotic resistance in BSIs, analyzing 387 blood samples from December 2021 to April 2023. The positivity rate for NTS (69.5%, 269/387) nearly matches that of metagenomic next-generation sequencing (mNGS) (74.7%, 289/387; p=0.128) and surpasses the positivity rate of conventional blood culture (BC) (33.9%, 131/387; p<0.01). Frequent pathogens detected by NTS included Klebsiella pneumoniae (n=54), Pseudomonas aeruginosa (n=36), Escherichia coli (n=36), Enterococcus faecium(n=30), Acinetobacter baumannii(n=26), Staphylococcus aureus(n=23), and Human cytomegalovirus (n=37). Against a composite BSI diagnostic standard, NTS demonstrated a sensitivity and specificity of 84.0% (95% CI 79.5%-87.7%) and 90.1% (95% CI 81.7%-88.5%), respectively. The concordance between NTS and mNGS results (the percentage of total cases where both either detected BSI-related pathogens or were both negative) was 90.2% (359/387), whereas the consistency between NTS and BC was only 60.2% (233/387). In 80.6% (50/62) of the samples with identical pathogens identified by both NTS tests and BCs, the genotypic resistance identified by NTS correlated with culture-confirmed phenotypic resistance. Using NTS, 95% of samples can be tested and analyzed in approximately 7h, allowing for early patient diagnosis. NTS is rapid, sensitive, and efficient for detecting BSIs and drug-resistant genes, making it a potential preferred diagnostic tool for early infection identification in critically ill patients.

Genomic epidemiology reveals geographical clustering of multidrug-resistant Escherichia coli ST131 associated with bacteraemia in Wales

Antibiotic resistance is a significant global public health concern. Uropathogenic Escherichia coli sequence type (ST)131, a widely prevalent multidrug-resistant clone, is frequently associated with bacteraemia. This study investigates third-generation cephalosporin resistance in bloodstream infections caused by E. coli ST131. From 2013-2014 blood culture surveillance in Wales, 142 E. coli ST131 genomes were studied alongside global data. All three major ST131 clades were represented across Wales, with clade C/H30 predominant (n = 102/142, 71.8%). Consistent with global findings, Welsh strains of clade C/H30 contain β-lactamase genes from the blaCTX-M-1 group (n = 65/102, 63.7%), which confer resistance to third-generation cephalosporins. Most Welsh clade C/H30 genomes belonged to sub-clade C2/H30Rx (58.3%). A Wales-specific sub-lineage, named GB-WLS.C2, diverged around 1996-2000. An introduction to North Wales around 2002 led to a localised cluster by 2009, depicting limited genomic diversity within North Wales. This investigation emphasises the value of genomic epidemiology, allowing the detection of genetically similar strains in local areas, enabling targeted and timely public health interventions.

Individual and population level costs and health-related quality of life outcomes of third-generation cephalosporin resistant bloodstream infection in Blantyre, Malawi.

Data which accurately enumerate the economic costs of antimicrobial resistance (AMR) in low- and middle- income countries are essential. This study aimed to quantify the impact of third-generation cephalosporin resistant (3GC-R) bloodstream infection (BSI) on economic and health related quality of life outcomes for adult patients in Blantyre, Malawi. Participants were recruited from a prospective, longitudinal cohort study of hospitalised patients with bloodstream infection caused by Enterobacterales at Queen Elizabeth Central Hospital (QECH). Primary costing studies were used to estimate the direct medical costs associated with the inpatient stay. Recruited participants were asked about direct non-medical and indirect costs associated with their admission and their health-related quality of life was measured using the EuroQol EQ-5D questionnaire. Multiple imputation was undertaken to account for missing data. Costs were adjusted to 2019 US Dollars. Cost and microbiology surveillance data from QECH, Blantyre was used to model the annual cost of, and quality-adjusted life years lost to, 3GC-R and 3GC-Susceptible BSI from 1998 to 2030 in Malawi. The mean health provider cost per participant with 3GC-R BSI was US$110.27 (95%CR; 22.60-197.95), higher than for those with 3GC-S infection. Patients with resistant BSI incurred an additional indirect cost of US$155.48 (95%CR; -67.80, 378.78) and an additional direct non-medical cost of US$20.98 (95%CR; -36.47, 78.42). Health related quality of life outcomes were poor for all participants, but participants with resistant infections had an EQ-5D utility score that was 0.167 (95% CR: -0.035, 0.300) lower than those with sensitive infections. Population level burden estimates suggest that in 2016, 3GC-R accounted for 84% of annual societal costs from admission with bloodstream infection and 82% of QALYs lost. 3GC-R bloodstream infection was associated with higher health provider and patient level costs than 3GC-S infection, as well as poorer HRQoL outcomes. We demonstrate a substantial current and future economic burden to society as a result of 3GC-R E. coli and Klebsiella spp. BSI, data urgently needed by policy makers to provide impetus for implementing strategies to reduce AMR.

Clinical spectrum and outcomes of carbapenem resistant infections in patients with acute leukaemia: A clinical study from a tertiary oncology centre in India.

e19020 Background: The prevalence of carbapenem resistant organisms (CRO) are increasing worldwide and associated with grave implications in patients with hematological malignancies. Data on such infections in patients with acute leukemia are scarce, especially from the developing world. The aim of this study was to evaluate characteristics and outcomes of bacteremia with CRO in patients treated for acute leukemia with aggressive chemotherapy regimens. Methods: This prospective observational study was conducted in a tertiary oncology centre in South India. Data on Carbapenem resistant bloodstream infection (CRBSI) in patients with acute leukemia (ALL and AML) aged 14-60 years, from March 2017 to February 2018 were prospectively collected. The final outcome was determined as survival and all-cause death due to CRBSI. Results: Out of 334 patients treated for acute leukemia, 49 patients developed infections with CRO (14.6%). The patients included 27 males (55%) and 22 females (45%), with age ranging from 14 year to 58 years (median age: 42 years). The most common isolates were Klebsiella species (63%) and E.coli (25%). All carbapenem resistant isolates were sensitive to Colistin and 74% were sensitive to Tigecycline. The case-fatality rate was 69% (34/49) in our cohort. Acute kidney injury, shock, septicemia and an initial procalcitonin value &gt; 1mcg/L were predictor of mortality. Disease in remission and neutrophil count recovery post chemotherapy were favorable factors associated with the outcome. There was no statistically significant difference in mortality in patients treated with single agent antibiotics versus combination antibiotics sensitive against CRO. Conclusions: Carbapenem resistant infections in patients with acute leukaemia are associated with a high mortality rate. The factors associated with improved outcome were disease in remission and neutrophil count recovery, post chemotherapy. The presence of acute kidney injury, shock, sepsis and a procalcitonin value more than 1 mcg/L were significant predictor of mortality.

The Hidden Cost of COVID-19: Focus on Antimicrobial Resistance in Bloodstream Infections.

Antibiotic resistance is one of the greatest growing public health threats and a worldwide priority. According to the WHO, drug-resistant diseases may cause 10 million deaths a year by 2050 and have a substantial impact on the global economy, driving up to 24 million people into poverty. The ongoing COVID-19 pandemic has exposed the fallacies and vulnerability of healthcare systems worldwide, displacing resources from existing programs and reducing funding for antimicrobial resistance (AMR) fighting efforts. Moreover, as already seen for other respiratory viruses, such as flu, COVID-19 is often associated with superinfections, prolonged hospital stays, and increased ICU admissions, further aggravating healthcare disruption. These events are accompanied by widespread antibiotic use, misuse, and inappropriate compliance with standard procedures with a potential long-term impact on AMR. Still, COVID-19-related measures such as increasing personal and environmental hygiene, social distancing, and decreasing hospital admissions could theoretically help the AMR cause. However, several reports have shown increased antimicrobial resistance during the COVID-19 pandemic. This narrative review focuses on this "twindemic", assessing the current knowledge of antimicrobial resistance in the COVID-19 era with a focus on bloodstream infections and provides insights into the lessons learned in the COVID-19 field that could be applied to antimicrobial stewardship initiatives.

The small RNA PrrH of Pseudomonas aeruginosa regulates hemolysis and oxidative resistance in bloodstream infection

Small regulatory RNAs (sRNAs) regulate multiple physiological functions in bacteria, and sRNA PrrH can regulate iron homeostasis and virulence. However, the function of PrrH in Pseudomonas aeruginosa (P. aeruginosa) bloodstream infection (BSI) is largely unknown. The aim of this study was to investigate the role of PrrH in P. aeruginosa BSI model. First, P. aeruginosa PAO1 was co-cultured with peripheral blood cells for 6 h. qRT-PCR results showed a transient up-regulation of PrrH expression at 1 h. Simultaneously, the expression of iron uptake genes fpvA, pvdS and phuR were upregulated. In addition, the use of iron chelator 2,2′-dipyridyl to create low-iron conditions caused up-regulation of PrrH expression, a result similar to the BSI model. Furthermore, the addition of FeCl3 was found to decrease PrrH expression. These results support the hypothesis that the expression of PrrH is regulated by iron in BSI model. Then, to clarify the effect of PrrH on major cells in the blood, we used PrrH mutant, overexpressing and wild-type strains to act separately on erythrocytes and neutrophils. On one hand, the hemolysis assay revealed that PrrH contributes to the hemolytic activity of PAO1, and its effect was dependent on the T3SS system master regulator gene exsA, yet had no association with the hemolytic phospholipase C (plcH), pldA, and lasB elastase genes. On the other hand, PrrH mutant enhanced the oxidative resistance of PAO1 in the neutrophils co-culture assay, H2O2-treated growth curve and conventional plate spotting assays. Furthermore, the katA was predicted to be a target gene of PrrH by bioinformatics software, and then verified by qRT-PCR and GFP reporter system. In summary, dynamic changes in the expression of prrH are iron-regulated during PAO1 bloodstream infection. In addition, PrrH promotes the hemolytic activity of P. aeruginosa in an exsA-dependent manner and negatively regulates katA to reduce the oxidative tolerance of P. aeruginosa.

Prevalence of multidrug resistant bloodstream infections in febrile neutropenic patients with hematolymphoid malignancies: A retrospective observational study from a newly established tertiary oncology center in India

Prevalence of multidrug resistant bloodstream infections in febrile neutropenic patients with hematolymphoid malignancies: A retrospective observational study from a newly established tertiary oncology center in India

Differences in the distribution of pathogens and antimicrobial resistance in bloodstream infections in migrants compared with non-migrants in Denmark

Background We wish to study disparities in bloodstream infections in migrants and non-migrants by comparing the distribution of pathogens and their resistance patterns in long-term migrants with that in non-migrants in Denmark. Methods The study is based on a cohort of migrants, who received residency in Denmark between 1993 and 2015 and a control group of non-migrants. The cohort was linked to a database of bloodstream infections from 2000 to 2015 covering two regions in Denmark. First-time bloodstream infections in individuals ≥18 years of age at the time of sampling were included. We calculated odds ratios adjusted for age, sex, year of sampling, comorbidity, and place of acquisition (hospital- or community-acquired). Results We identified 4,703 bloodstream infection cases. Family-reunified migrants and refugees had higher odds of Escherichia coli than non-migrants (OR 1.89 95%CI: 1.46–2.44 and OR 1.55 95%CI: 1.25–1.92) and lower odds of Streptococcus pneumoniae (OR 0.38 95%CI: 0.21–0.67 and OR 0.52 95%CI: 0.34–0.81). Differences in pathogen distribution were only prevalent in community-acquired bloodstream infections. Refugees had higher odds of Escherichia coli resistant to piperacillin-tazobactam, ciprofloxacin, and gentamicin compared with non-migrants. Family-reunified migrants had higher odds of Escherichia coli and other Enterobacterales resistant to ciprofloxacin. Conclusions Migrants had a higher proportion of community-acquired bloodstream infections with Escherichia coli as well as higher odds of bloodstream infections with resistant Escherichia coli compared with non-migrants. These novel results are relevant for improving migrant health by focussing on preventing and treating infections especially with Escherichia coli such as urinary tract and abdominal infections.

Effect of temperature on Escherichia coli bloodstream infection in a nationwide population-based study of incidence and resistance

BackgroundThe incidence of Escherichia coli bloodstream infections (BSI) is high and increasing. We aimed to describe the effect of season and temperature on the incidence of E. coli BSI and antibiotic-resistant E. coli BSI and to determine differences by place of BSI onset.MethodsAll E. coli BSI in adult Israeli residents between January 1, 2018 and December 19, 2019 were included. We used the national database of mandatory BSI reports and outdoor temperature data. Monthly incidence and resistance were studied using multivariable negative binomial regressions with season (July–October vs. other) and temperature as covariates.ResultsWe included 10,583 events, 9012 (85%) community onset (CO) and 1571 (15%) hospital onset (HO). For CO events, for each average monthly temperature increase of 5.5 °C, the monthly number of events increased by 6.2% (95% CI 1.6–11.1%, p = 0.008) and the monthly number of multidrug-resistant events increased by 4.9% (95% CI 0.3–9.7%, p = 0.04). The effect of season was not significant. For HO events, incidence of BSI and resistant BSI were not associated with temperature or season.ConclusionTemperature increases the incidence of CO E. coli BSI and CO antibiotic-resistant E. coli BSI. Global warming threatens to increase the incidence of E. coli BSI.

Patterns of microbial resistance in bloodstream infections of hemodialysis patients: a cross-sectional study from Palestine

Bloodstream infections (BSIs) are a prominent cause of death and hospitalization among hemodialysis (HD) patients. The emergence of multidrug-resistant organisms (MDRO) is making the management of these infections more challenging. This study describes the clinical characteristics, microbial profiles and antibiotic resistance patterns in patients with BSIs. A retrospective cross-sectional study was conducted at An-Najah National University Hospital from January 2019 to December 2020. Clinical and demographic data regarding BSIs were collected from the hospital information system. Data regarding bacterial isolates and the antimicrobial resistance of BSIs were collected from the microbiology lab. Data were entered and analyzed using version 21 of the Statistical Package for Social Sciences program (IBM-SPSS). 111 BSIs occurred during the study period, with a rate of 1.5 infections per 100 patient-months. These patients had been on HD for the median duration of 747 (360, 1825) days and 62.2% had already had a BSI before the study period. 118 microorganisms were isolated; 99 (83.89%) were gram-positive and 19 (16.1%) were gram-negative. Among the gram-positive isolates, coagulase-negative staphylococci (CoNS) (88, 74.57%) were predominant. As for the gram-negative isolates, the most frequent were both Stenotrophomonas maltophilia and Escherichia coli, with five (4.23%) positive cultures each. Among the latter, two were Extended-Spectrum Beta-Lactamase producing (ESBL) (1.69%). The most frequently used empiric antibiotics were a combination of vancomycin and gentamicin (27%), followed by vancomycin alone (24.3%). Regarding gram-positive isolates, vancomycin was the most frequently used and effective antibiotic after cultures, whereas for gram-negative bacteria, it was found to be gentamicin. MDROs were defined as those resistant to at least one agent in three or more antimicrobial categories. 89 (75.4%) isolates were found to be MDRO, 85 (85.85%) gram-positive bacteria and 4 (21%) gram-negative bacteria. When comparing patients according to the type of vascular access, 66 (75%) infections with MDRO were found among patients with central venous catheters (CVCs). However, no statistically significant relationship was found between the type of vascular access and infection with MDRO (p = 0.523). MDRO cause a remarkably high proportion of BSIs in Palestinian patients. The results of this study support the empiric use of vancomycin and gentamicin to treat these infections. It is vital that health care providers prevent these infections via instituting and adhering to infection control policies in hemodialysis centers and providing proper antibiotic therapy of limited use and duration when necessary to avoid breeding resistance.

Prevalence and Antimicrobial Resistance of Bloodstream Infections Caused by ESKAPEEc Pathogens: A Five-Year Analysis

Background: Antimicrobial resistance in ESKAPEEc (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, Enterobacter species, and Escherichia coli) pathogens causing bloodstream infections is a growing threat to clinicians and public health. Objectives: Our purpose was to determine the prevalence and susceptibility of ESKAPEEcs causing bloodstream infection over five years (2016 to 2020) at a large tertiary hospital in Istanbul, Turkey. Methods: Of 2591 unique isolates obtained from blood culture specimens, 1.281 (49.4%) were positive for ESKAPEEc pathogens. The ESKAPEEc rates increased from 2016 to 2019 and decreased during the COVID-19 pandemic. Results: The most common pathogen was K. pneumoniae (34.3%). Carbapenem resistant K. pneumoniae was 61.8% and A. baumannii was 90.4%. The percentages of methicillin-resistant S. aureus and vancomycin-resistant E. faecium were 38.6% and 29.4%, respectively. Conclusions: Our findings showed a high incidence of ESKAPEEc and antimicrobial resistance in bloodstream infections. Antibiotic policies and restrictions in health care settings and the community will play an essential role in the solution in the future.

Risk Factors for a Hospital-Acquired Carbapenem-Resistant Klebsiella pneumoniae Bloodstream Infection: A Five-Year Retrospective Study.

PurposeThis study aimed to describe trends in Klebsiella pneumoniae (KP) resistance in bloodstream infections (BSI) and to identify risk factors for a hospital-acquired carbapenem-resistant Klebsiella pneumoniae (CRKP) BSI and 28-day mortality from a hospital-acquired KP BSI.Patients and MethodsWe recorded the results of antimicrobial susceptibility testing of 396 KP-positive blood cultures from January 2016 to December 2020. A total of 277 patients with a KP BSI were included in this study, of which 171 had a hospital-acquired infection and 84 had a hospital-acquired CRKP BSI. Multivariate logistic regression analysis was used to identify risk factors for a hospital-acquired CRKP BSI and 28-day mortality from a hospital-acquired KP BSI.ResultsThe proportion of hospital-acquired infections among KP BSI patients increased from 53.1% in 2016 to 72.8% in 2020. The detection rate of CRKP among KP BSI patients increased from 18.8% in 2016 to 37.7% in 2020. Multivariate logistic regression showed that β-lactam/β-lactamase inhibitor combinations (BLBLIs) exposure (P = 0.022, OR 2.863), carbapenems exposure (P = 0.007, OR 3.831) and solid organ transplantation (P <0.001, OR 19.454) were independent risk factors for a hospital-acquired CRKP BSI. Risk factors for a 28-day mortality from hospital-acquired KP BSI were CRKP BSI (P =0.009, OR 5.562), septic shock (P =0.002, OR 4.862), mechanical ventilation>96 hours (P =0.020, OR 8.765), and platelet counts <100×109/L (P =0.003, OR 4.464).ConclusionThe incidence of hospital-acquired KP BSI continues to rise and the proportion of CRKP BSI is also increasing. We believe that the use of the BLBLIs needs to be carefully evaluated in hospital-acquired infection. Hospital-acquired KP BSI Patients with CRKP BSI, septic shock, mechanical ventilation and deficiency of platelets are more likely to have a poor prognosis.

Trends in antimicrobial resistance in bloodstream infections at a large tertiary-care hospital in China: a 10-year retrospective study (2010–2019)

Bloodstream infections (BSIs) are a major cause of morbidity and mortality worldwide. This study aimed to explore the distribution and antimicrobial resistance of BSI pathogens at a tertiary-care hospital in China. Surveillance blood cultures were routinely taken from patients with fever or suspected sepsis from 2010-2019 at the First Affiliated Hospital of Zhengzhou University. Isolate identification was performed by VITEK®2 Compact and/or VITEK® MS. Antimicrobial susceptibility testing was carried out by MIC determination and/or disk diffusion. Totally, 18 180 strains were isolated from blood cultures, the most common being Escherichia coli (21.7%), followed by coagulase-negative staphylococci (CoNS) (18.8%), Klebsiella pneumoniae (13.0%) and Staphylococcus aureus (6.6%). Escherichia coli resistance rates to ceftazidime, ceftriaxone, cefepime and aztreonam showed a significant declining trend, and the frequency of carbapenem-resistant E. coli was <6.0% over time. Noteworthy, the proportion of carbapenem-resistant K. pneumoniae exhibited a sharp upward trend (from 6.7% to 56.7%). The prevalence of carbapenem-resistant A. baumannii remained at a high level (>75%). Pseudomonas aeruginosa resistance rates against all tested agents were <25%, and resistance rates to aminoglycosides and fluoroquinolones showed a significant downward trend. The frequency of methicillin-resistant CoNS maintained a high level (>70%), however the isolation rate of MRSA ranged from 58.0% to 34.7%, showing a significant decline. The dramatic increase in carbapenem-resistant K. pneumoniae during 10 years was noteworthy. Effective infection control measures and stewardship efforts should be taken to prevent their spread. Our results indicate the importance of active surveillance for aetiology and resistance of BSI isolates.

Pathogens distribution and antimicrobial resistance in bloodstream infections in twenty-five neonatal intensive care units in China, 2017\u20132019

BackgroundOvercrowding, abuse of antibiotics and increasing antimicrobial resistance negatively affect neonatal survival rates in developing countries. We aimed to define pathogens and their antimicrobial resistance (AMR) of early-onset sepsis (EOS), hospital-acquired late-onset sepsis (HALOS) and community-acquired late-onset sepsis (CALOS) in 25 neonatal intensive care units (NICUs) in China.Study designThis retrospective descriptive study included pathogens and their AMR from all neonates with bloodstream infections (BSIs) admitted to 25 tertiary hospitals in China from January 1, 2017, and December 31, 2019. We defined EOS as the occurrence of BSI at or before 72 h of life and late-onset sepsis (LOS) if BSI occurred after 72 h of life. LOS were classified as CALOS if occurrence of BSI was ≤ 48 h after admission, and HALOS, if occurrence was > 48 h after admission.ResultsWe identified 1092 pathogens of BSIs in 1088 infants from 25 NICUs. Thirty-two percent of all pathogens were responsible for EOS, 64.3% HALOS, and 3.7% CALOS. Gram-negative (GN) bacteria accounted for a majority of pathogens in EOS (56.7%) and HALOS (62.2%). The most frequent pathogens causing EOS were Escherichia coli (27.2%) and group B streptococcus (GBS; 14.6%) whereas in CALOS they were GBS (46.3%) and Staphylococcus aureus (41.5%). Klebsiella pneumoniae (27.9%), Escherichia coli (15.7%) and Fungi (12.8%) were the top three isolates in HALOS. Third-generation cephalosporin resistance rates in GN bacteria ranged from 9.7 to 55.6% in EOS and 26% to 63.3% in HALOS. Carbapenem resistance rates in GN bacteria ranged from 2.7 to 31.3% in HALOS and only six isolates in EOS were carbapenem resistant. High rates of multidrug resistance were observed in Klebsiella pneumoniae (60.7%) in HALOS and in Escherichia coli (44.4%) in EOS. All gram-positive bacteria were susceptible to vancomycin except for three Enterococcus faecalis in HALOS. All-cause mortality was higher among neonates with EOS than HALOS (7.4% VS 4.4%, [OR] 0.577, 95% CI 0.337–0.989; P = 0.045).ConclusionsEscherichia coli, Klebsiella pneumoniae and GBS were the leading pathogens in EOS, HALOS and CALOS, respectively. The high proportion of pathogens and high degree of antimicrobial resistance in HALOS underscore understanding of the pathogenesis and emphasise the need to devise effective interventions in developing countries.

Prevalence and Outcomes of Multi-Drug Resistant Blood Stream Infections Among Nursing Home Residents Admitted to an Acute Care Hospital.

The prevalence of multi-drug resistant organism (MDRO) colonization in nursing home residents has been well documented, but little is known about the impact of MDRO bloodstream infections (BSIs). The aim of this study was to assess the prevalence, cost, and outcomes of MDRO-BSI vs. non-MDRO-BSI among nursing home residents. Retrospective cohort study. 960 bed tertiary academic medical center. Persons ≥18 years old admitted to an acute care tertiary hospital from Skilled Nursing Facilities with a diagnosis of sepsis between 2015 and 2018. Retrospective analysis of prevalence and outcomes. Among patients admitted to the study hospital with a diagnosis of sepsis during the study period, 7% were from nursing homes. The prevalence of MDRO-BSI was 47%. We identified 54 (50%) gram positive BSIs, 48 (45%) gram negative BSI and 5 (5%) fungal BSI. Thirty-one (57%) of the gram-positive infections and 14 (30%) of the gram-negative infections were with MDROs. The prevalence of BSI organisms were Staphylococcus aureus in 24%, Escherichia coli in 14%, Proteus mirabilis in 13%, Staphylococcus epidermidis in 8%, Enterococcus faecalis in 7%, and Klebsiella pneumoniae in 6%. We found that intensive care unit length of stay (7 days vs 5 days, P = .009), direct cost ($13,639 vs $9,922, P = .027), and total cost ($23,752 vs $17,900 P = .032) were significantly higher in patients with MDRO-BSI vs. non-MDRO-BSI. Patients with MDRO-BSI were twice as likely to receive inappropriate empiric antiinfective therapy (31% vs 16%, P = .006) and were more likely to die (49.1% vs 29.6%, P = .049). Nursing home residents have a high prevalence of MDRO-BSI, which is associated with higher risk of receiving inappropriate initial anti-infective therapy, higher cost, higher ICU LOS, and higher mortality. Our research adds new information about the prevalence of fungemia in this population.

Antibiotic Resistant Bloodstream Infections in Pediatric Patients Receiving Chemotherapy or Hematopoietic Stem Cell Transplant: Factors Associated with Development of Resistance, Intensive Care Admission and Mortality

Bloodstream infections (BSI) are a severe complication of antineoplastic chemotherapy or hematopoietic stem cell transplantation (HSCT), especially in the presence of antibiotic resistance (AR). A multinational, multicenter retrospective study in patients aged ≤ 18 years, treated with chemotherapy or HSCT from 2015 to 2017 was implemented to analyze AR among non-common skin commensals BSI. Risk factors associated with AR, intensive care unit (ICU) admission and mortality were analyzed by multilevel mixed effects or standard logistic regressions. A total of 1291 BSIs with 1379 strains were reported in 1031 patients. Among Gram-negatives more than 20% were resistant to ceftazidime, cefepime, piperacillin-tazobactam and ciprofloxacin while 9% was resistant to meropenem. Methicillin-resistance was observed in 17% of S. aureus and vancomycin resistance in 40% of E. faecium. Previous exposure to antibiotics, especially to carbapenems, was significantly associated with resistant Gram-negative BSI while previous colonization with methicillin-resistant S. aureus was associated with BSI due to this pathogen. Hematological malignancies, neutropenia and Gram-negatives resistant to >3 antibiotics were significantly associated with higher risk of ICU admission. Underlying disease in relapse/progression, previous exposure to antibiotics, and need of ICU admission were significantly associated with mortality. Center-level variation showed a greater impact on AR, while patient-level variation had more effect on ICU admission and mortality. Previous exposure to antibiotics or colonization by resistant pathogens can be the cause of AR BSI. Resistant Gram-negatives are significantly associated with ICU admission and mortality, with a significant role for the treating center too. The significant evidence of center-level variations on AR, ICU admission and mortality, stress the need for careful local antibiotic stewardship and infection control programs.

Analysis of Pathogen Distribution and Its Antimicrobial Resistance in Bloodstream Infections in Hospitalized Children in East China, 2015-2018.

This study analyzed the pathogen distribution in bloodstream-infected (BSI) children hospitalized in Shandong Province from 2015 to 2018, to identify prevention strategies and select empiric antimicrobial therapy for BSI in children. Blood sample data from 14 107 children from 162 hospitals of Shandong Province were obtained from the China Antimicrobial Resistance Surveillance System and analyzed with WHONET 5.6 software. The results of the blood culture test showed the growth of 70.6% Gram-positive and 29.4% Gram-negative bacteria. Of the 14 107 blood isolates, 59.3% were collected from males and 40.7% were from females. Coagulase-negative staphylococci (47.1%) were the most commonly distributed pathogens. The distribution of pathogens varied according to age group and season. All Staphylococcus isolates were susceptible to vancomycin, teicoplanin and linezolid. Clinically, significant declines in penicillin-resistant Streptococcus pneumonia and carbapenem-resistant Escherichia coli were observed during the study period; however, detection rates of carbapenem-resistant Klebsiella pneumoniae increased over time (p < 0.05). Empiric antimicrobial therapy should be prescribed according to corresponding regional pediatric antimicrobial-resistant data.

Epidemiology and Outcomes of Bloodstream Infections in HIV-Patients during a 13-Year Period.

No data on antibiotic resistance in bloodstream infection (BSI) in people living with HIV (PLWH) exist. The objective of this study was to describe BSI epidemiology in PLWH focusing on multidrug resistant (MDR) organisms. A retrospective, single-center, observational study was conducted including all positive blood isolates in PLWH from 2004 to 2017. Univariable and multivariable GEE models using binomial distribution family were created to evaluate the association between MDR and mortality risk. In total, 263 episodes (299 isolates) from 164 patients were analyzed; 126 (48%) BSI were community-acquired, 137 (52%) hospital-acquired. At diagnosis, 34.7% of the patients had virological failure, median CD4 count was 207/μL. Thirty- and 90-day mortality rates were 24.2% and 32.4%, respectively. Thirty- and 90-day mortality rates for MDR isolates were 33.3% and 46.9%, respectively (p < 0.05). Enterobacteriaceae were the most prevalent microorganisms (29.8%), followed by Coagulase-negative staphylococci (21.4%), and S. aureus (12.7%). In BSI due to MDR organisms, carbapenem-resistant K. pneumoniae and methicillin-resistant S. aureus were associated with mortality after adjustment for age, although this correlation was not confirmed after further adjustment for CD4 < 200/μL. In conclusion, BSI in PLWH is still a major problem in the combination antiretroviral treatment era and it is related to a poor viro-immunological status, posing the question of whether it should be considered as an AIDS-defining event.