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Journal of Clinical Microbiology Mar 2022There has been significant progress in detection of bloodstream pathogens in recent decades with the development of more sensitive automated blood culture detection... (Review)
Review
There has been significant progress in detection of bloodstream pathogens in recent decades with the development of more sensitive automated blood culture detection systems and the availability of rapid molecular tests for faster organism identification and detection of resistance genes. However, most blood cultures in clinical practice do not grow organisms, suggesting that suboptimal blood culture collection practices (e.g., suboptimal blood volume) or suboptimal selection of patients to culture (i.e., blood cultures ordered for patients with low likelihood of bacteremia) may be occurring. A national blood culture utilization benchmark does not exist, nor do specific guidelines on when blood cultures are appropriate or when blood cultures are of low value and waste resources. Studies evaluating the potential harm associated with excessive blood cultures have focused on blood culture contamination, which has been associated with significant increases in health care costs and negative consequences for patients related to exposure to unnecessary antibiotics and additional testing. Optimizing blood culture performance is important to ensure bloodstream infections (BSIs) are diagnosed while minimizing adverse events from overuse. In this review, we discuss key factors that influence blood culture performance, with a focus on the preanalytical phase, including technical aspects of the blood culture collection process and blood culture indications. We highlight areas for improvement and make recommendations to improve current blood culture practices among hospitalized patients.
Topics: Anti-Bacterial Agents; Bacteremia; Blood Culture; Hospitals; Humans; Sepsis
PubMed: 34260274
DOI: 10.1128/JCM.01005-21 -
Clinical Microbiology and Infection :... Aug 2022Precise estimates of mortality in Staphylococcus aureus bacteraemia (SAB) are important to convey prognosis and guide the design of interventional studies. (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Precise estimates of mortality in Staphylococcus aureus bacteraemia (SAB) are important to convey prognosis and guide the design of interventional studies.
OBJECTIVES
We performed a systematic review and meta-analysis to estimate all-cause mortality in SAB and explore mortality change over time.
DATA SOURCES
The MEDLINE and Embase databases, as well as the Cochrane Database of Systematic Reviews, were searched from January 1, 1991 to May 7, 2021.
STUDY ELIGIBILITY CRITERIA
Human observational studies on patients with S. aureus bloodstream infection were included.
PARTICIPANTS
The study analyzed data of patients with a positive blood culture for S. aureus.
METHODS
Two independent reviewers extracted study data and assessed risk of bias using the Newcastle-Ottawa Scale. A generalized, linear, mixed random effects model was used to pool estimates.
RESULTS
A total of 341 studies were included, describing a total of 536,791 patients. From 2011 onward, the estimated mortality was 10.4% (95% CI, 9.0%-12.1%) at 7 days, 13.3% (95% CI, 11.1%-15.8%) at 2 weeks, 18.1% (95% CI, 16.3%-20.0%) at 1 month, 27.0% (95% CI, 21.5%-33.3%) at 3 months, and 30.2% (95% CI, 22.4%-39.3%) at 1 year. In a meta-regression model of 1-month mortality, methicillin-resistant S. aureus had a higher mortality rate (adjusted OR (aOR): 1.04; 95% CI, 1.02-1.06 per 10% increase in methicillin-resistant S. aureus proportion). Compared with prior to 2001, more recent time periods had a lower mortality rate (aOR: 0.88; 95% CI, 0.75-1.03 for 2001-2010; aOR: 0.82; 95% CI, 0.69-0.97 for 2011 onward).
CONCLUSIONS
SAB mortality has decreased over the last 3 decades. However, more than one in four patients will die within 3 months, and continuous improvement in care remains necessary.
Topics: Anti-Bacterial Agents; Bacteremia; Humans; Methicillin-Resistant Staphylococcus aureus; Sepsis; Staphylococcal Infections; Staphylococcus aureus
PubMed: 35339678
DOI: 10.1016/j.cmi.2022.03.015 -
Clinical Microbiology and Infection :... Feb 2020Bloodstream infections comprise a wide variety of pathogens and clinical syndromes with considerable overlap with similar syndromes of non-bacteraemic infections and... (Review)
Review
BACKGROUND
Bloodstream infections comprise a wide variety of pathogens and clinical syndromes with considerable overlap with similar syndromes of non-bacteraemic infections and diverse risk factors, therapeutic implications and outcomes. Yet, this heterogeneous 'entity' has the advantage to be pathogen-defined compared with the broad and even more heterogeneous entity 'sepsis', and so has become helpful for clinicians and epidemiologists for research and surveillance purposes. The increasing availability of population-based and large multicentre well-defined cohort studies should allow us to assess with much confidence and in detail its burden, the significance of antimicrobial resistance, and areas of uncertainty regarding further epidemiological evolution and optimized treatment regimens.
AIM
To review key aspects of bloodstream infection epidemiology and burden, and summarize recent news and questions concerning critical developments.
SOURCES
Peer-reviewed articles based on the search terms 'bloodstream infection' and 'bacteremia' combined with the terms 'epidemiology' and 'burden'. The emphasis was on new information from studies in adult patients and on the added burden due to pathogen resistance to first- and second-line antimicrobial agents.
CONTENT
Topics covered include recent developments in the epidemiology of bloodstream infection due to key pathogens and published information about the relevance of resistance for patient outcomes.
IMPLICATIONS
Despite the availability of population-based studies and an increasing number of large well-defined multicentre cohort studies, more surveillance and systematic data on bloodstream infection epidemiology at regional level and in resource-limited settings may be needed to better design new methods for prevention and define the need for and further develop optimized therapeutic strategies.
Topics: Anti-Bacterial Agents; Bacteremia; Bacteria; Cost of Illness; Cross Infection; Drug Resistance, Multiple, Bacterial; Global Health; Humans; Incidence; Microbial Sensitivity Tests
PubMed: 31712069
DOI: 10.1016/j.cmi.2019.10.031 -
Intensive Care Medicine Feb 2020Bloodstream infection (BSI) is defined by positive blood cultures in a patient with systemic signs of infection and may be either secondary to a documented source or...
Bloodstream infection (BSI) is defined by positive blood cultures in a patient with systemic signs of infection and may be either secondary to a documented source or primary-that is, without identified origin. Community-acquired BSIs in immunocompetent adults usually involve drug-susceptible bacteria, while healthcare-associated BSIs are frequently due to multidrug-resistant (MDR) strains. Early adequate antimicrobial therapy is a key to improve patient outcomes, especially in those with criteria for sepsis or septic shock, and should be based on guidelines and direct examination of available samples. Local epidemiology, suspected source, immune status, previous antimicrobial exposure, and documented colonization with MDR bacteria must be considered for the choice of first-line antimicrobials in healthcare-associated and hospital-acquired BSIs. Early genotypic or phenotypic tests are now available for bacterial identification and early detection of resistance mechanisms and may help, though their clinical impact warrants further investigations. Initial antimicrobial dosing should take into account the pharmacokinetic alterations commonly observed in ICU patients, with a loading dose in case of sepsis or septic shock. Initial antimicrobial combination attempting to increase the antimicrobial spectrum should be discussed when MDR bacteria are suspected and/or in the most severely ill patients. Source identification and control should be performed as soon as the hemodynamic status is stabilized. De-escalation from a broad-spectrum to a narrow-spectrum antimicrobial may reduce antibiotic selection pressure without negative impact on mortality. The duration of therapy is usually 5-8 days though longer durations may be discussed depending on the underlying illness and the source of infection. This narrative review covers the epidemiology, diagnostic workflow and therapeutic aspects of BSI in ICU patients and proposed up-to-date expert statements.
Topics: Anti-Bacterial Agents; Bacteremia; Blood Culture; Critical Illness; Drug Monitoring; Expert Testimony; Humans; Intensive Care Units; Prevalence; Time Factors
PubMed: 32047941
DOI: 10.1007/s00134-020-05950-6 -
Clinical Microbiology and Infection :... Mar 2021Enterococcal bacteraemia (EB) is common, particularly in the nosocomial setting, and its management poses a challenge for clinicians and microbiologists. (Review)
Review
BACKGROUND
Enterococcal bacteraemia (EB) is common, particularly in the nosocomial setting, and its management poses a challenge for clinicians and microbiologists.
OBJECTIVES
The aim was to summarize the more relevant features of EB and to provide a practical state-of-the-art on the topics that more directly affect its management.
SOURCES
Pubmed articles from inception to 31 May 2020.
CONTENT
The following topics are covered: epidemiological, clinical and microbiological characteristics and factors associated with prognosis of EB; diagnosis and work-up, including the use of echocardiography to rule out endocarditis; antibiotic management with special focus on antimicrobial resistance and complicated EB; and the role of infectious disease consultation and the use of bundles in EB. In addition, three clinical vignettes are presented to illustrate the practical application of the guidance provided, and major gaps in the current evidence supporting EB management are discussed.
IMPLICATIONS
EB is associated with large burdens of morbidity and mortality, particularly among fragile and immunosuppressed patients presenting complicated bacteraemia due to multidrug-resistant enterococci. Most cases of EB are caused by Enterococcus faecalis, followed by E. faecium. EB often presents as polymicrobial bacteraemia. Rapidly identifying patients at risk of EB is crucial for timely application of diagnostic techniques and empiric therapy. Early alert systems and rapid diagnostic techniques, such as matrix-assisted desorption ionization-time of flight mass spectrometry, especially if used together with infectious disease consultation within bundles, appear to improve management and prognosis of EB. Echocardiography is also key in the work-up of EB and should probably be more extensively used, although its exact indications in EB are still debated. Multidisciplinary approaches are warranted due to the complexity and severity of EB.
Topics: Bacteremia; Enterococcus; Gram-Positive Bacterial Infections; Humans
PubMed: 33152537
DOI: 10.1016/j.cmi.2020.10.029 -
Ugeskrift For Laeger Mar 2022Infective endocarditis (IE) is one of the most severe infectious diseases with an in-hospital mortality of 20-25%. Several studies have shown, that the incidence of IE... (Review)
Review
Infective endocarditis (IE) is one of the most severe infectious diseases with an in-hospital mortality of 20-25%. Several studies have shown, that the incidence of IE is increasing, and that patients now are older with a higher burden of comorbidities than previously. The diagnostic work-up is mainly based upon the presence of bacteraemia and echocardiography. The treatment is antibiotics and, in some cases, also cardiac surgery. In most cases, after clinical stabilization, it is safe to switch antibiotic treatment from intravenous to oral administration, as argued in this review.
Topics: Administration, Oral; Anti-Bacterial Agents; Bacteremia; Endocarditis; Endocarditis, Bacterial; Humans
PubMed: 35319455
DOI: No ID Found -
Pediatrics Jul 2019Previous studies examining bacteremia in hospitalized children with pneumonia are limited by incomplete culture data. We sought to determine characteristics of children...
BACKGROUND
Previous studies examining bacteremia in hospitalized children with pneumonia are limited by incomplete culture data. We sought to determine characteristics of children with bacteremic pneumonia using data from a large prospective study with systematic blood culturing.
METHODS
Children <18 years hospitalized with pneumonia and enrolled in the multicenter Etiology of Pneumonia in the Community study between January 2010 and June 2012 were eligible. Bivariate comparisons were used to identify factors associated with bacteremia. Associations between bacteremia and clinical outcomes were assessed by using Cox proportional hazards regression for length of stay and logistic regression for ICU admission and invasive mechanical ventilation or shock.
RESULTS
Blood cultures were obtained in 2143 (91%) of 2358 children; 46 (2.2%) had bacteremia. The most common pathogens were ( = 23, 50%), ( = 6, 13%), and ( = 4, 9%). Characteristics associated with bacteremia included male sex, parapneumonic effusion, lack of chest indrawing or wheezing, and no previous receipt of antibiotics. Children with bacteremia had longer lengths of stay (median: 5.8 vs 2.8 days; adjusted hazard ratio: 0.79 [0.73-0.86]) and increased odds of ICU admission (43% vs 21%; adjusted odds ratio: 5.21 [3.82-6.84]) and invasive mechanical ventilation or shock (30% vs 8%; adjusted odds ratio: 5.28 [2.41-11.57]).
CONCLUSIONS
Bacteremia was uncommonly detected in this large multicenter cohort of children hospitalized with community-acquired pneumonia but was associated with severe disease. was detected most often. Blood culture was of low yield in general but may have greater use in those with parapneumonic effusion and ICU admission.
Topics: Adolescent; Anti-Bacterial Agents; Bacteremia; Blood Culture; Child; Child, Preschool; Community-Acquired Infections; Critical Care; Female; Humans; Infant; Length of Stay; Male; Pneumonia, Bacterial; Prevalence; Proportional Hazards Models; Prospective Studies; Respiration, Artificial; Risk Factors; Treatment Outcome; United States
PubMed: 31217309
DOI: 10.1542/peds.2018-3090 -
Clinics in Laboratory Medicine Dec 2020The optimal care of septic patients depends on the successful recovery of clinically relevant microorganisms from blood cultures and the timely reporting of organism... (Review)
Review
The optimal care of septic patients depends on the successful recovery of clinically relevant microorganisms from blood cultures and the timely reporting of organism identification and antimicrobial susceptibility testing (AST) results. Many preanalytic factors play a critical role in culturing microorganisms, and advancements in blood culture instrument technology have reduced the time to positive results. Additionally, rapid organism identification and AST results directly from positive blood culture broth via new methods help to further shorten the time from empiric to targeted treatment. This article summarizes the current state of blood culture methods, including preanalytic, analytical, and postanalytic factors that are available to clinical microbiology laboratories.
Topics: Anti-Bacterial Agents; Antimicrobial Stewardship; Bacteremia; Bacteria; Blood Culture; Clinical Decision-Making; Humans; Microbial Sensitivity Tests
PubMed: 33121610
DOI: 10.1016/j.cll.2020.07.001 -
Clinical Microbiology and Infection :... Feb 2020Bloodstream infections (BSIs) are a major cause of morbidity and mortality in paediatric patients. For fast and accurate diagnosis, blood culture (BC) is the reference... (Review)
Review
BACKGROUND
Bloodstream infections (BSIs) are a major cause of morbidity and mortality in paediatric patients. For fast and accurate diagnosis, blood culture (BC) is the reference standard. However, the procedure for blood sampling in paediatric patients, particularly the optimal blood volume, is the subject of controversy stemming from a lack of knowledge of the bacterial load and because of several obstacles such as low intravascular volume and the risk of causing anaemia.
AIMS
The aim of this narrative review is to summarize current knowledge on blood sampling in paediatric patients for BC purposes, in particular blood volume and number and type of BC bottles needed for reasonable future guidelines/recommendations.
SOURCES
A comprehensive literature search of PubMed, including all publications in English, was performed in June 2019 using the search terms 'blood culture', 'blood volume', 'bloodstream infection', 'diagnostic', 'paediatric' and/or 'sepsis'.
CONTENT
The amount of inoculated blood determines the sensitivity, specificity and time to positivity of a BC, and low-level bacteraemia (≤10 cfu/mL) in paediatric patients is presumed to be more common than reported. Current approaches for 'adequate' blood volume for paediatric BC are mainly weight- or age-dependent. Of these recommendations, the scheme devised by Gaur and colleagues seems most appropriate and calls for a sample of 1-1.5 mL for children weighing <11 kg and 7.5 mL for a patient weight of 11-17 kg to be drawn into one BC bottle. Inclusion of a more detailed grading in the weight range 4-14 kg, as published by Gonsalves and colleagues, might be useful.
IMPLICATIONS
This review could be important for future guidelines on paediatric BC collection and thus could contribute to improving patient management and lowering the economic and global health burden associated with BSI. Furthermore, upcoming molecular-based approaches with low sample volumes might be an interesting alternative.
Topics: Bacteremia; Bacterial Load; Blood Culture; Blood Volume; Child; Clinical Trials as Topic; Cross-Sectional Studies; Humans; Infant, Newborn; Pediatrics; Sensitivity and Specificity; Time Factors
PubMed: 31654793
DOI: 10.1016/j.cmi.2019.10.006 -
Clinical Microbiology and Infection :... Feb 2022Staphylococcus aureus bloodstream infections are common and associated with a high mortality of 15-25%. Methicillin-resistant S. aureus (MRSA) bloodstream infection... (Review)
Review
BACKGROUND
Staphylococcus aureus bloodstream infections are common and associated with a high mortality of 15-25%. Methicillin-resistant S. aureus (MRSA) bloodstream infection accounts for 10-40% of cases, and has an even higher mortality. Despite being the 'bread and butter' of clinical infectious diseases practice, robust evidence to guide optimal management is often lacking and there is wide variation in practice.
OBJECTIVES
To provide a real-world example of a case of MRSA bacteraemia and the thought processes of the authors as key management decision points are reached.
SOURCES
The discussion is based on recent literature searches of relevant topics. In making recommendations, randomized clinical trial data have been prioritized and highlighted, and where these are not available recommendations are based on the experience and opinions of the authors.
CONTENT
For a patient with MRSA bacteraemia and a primary bone and joint infection the following points are discussed: empirical antibiotic choice for suspected S. aureus bacteraemia; directed antibiotic choice for MRSA; monitoring and dosing of vancomycin; the role of combination therapy when bacteraemia is persistent; and the duration of therapy and role of switching to oral antibiotics.
IMPLICATIONS
While broad principles of aggressive source control and appropriate choice and duration of antibiotics are important, the heterogeneity of S. aureus bacteraemia means that a tailored rather than algorithmic approach to management is often required. Further randomized controlled trials are needed to strengthen the evidence base for the management of MRSA bacteraemia.
Topics: Anti-Bacterial Agents; Bacteremia; Humans; Methicillin-Resistant Staphylococcus aureus; Randomized Controlled Trials as Topic; Staphylococcal Infections; Staphylococcus aureus; Vancomycin
PubMed: 34757117
DOI: 10.1016/j.cmi.2021.10.014