Search

BACKGROUND: Physicians tend to overestimate patients' pretest probability of having bacteremia. The low yield of blood cultures and contaminants is associated with significant financial cost, as well as increased length of stay and unnecessary antibiotic treatment.OBJECTIVE: This study examined the abilities of the National Early Warning Score (NEWS), the Quick Sequential Organ Failure Assessment (qSOFA), the Modified Sequential Organ Failure Assessment (mSOFA), and two versions of the causal probabilistic network, SepsisFinder™ (SF) to predict bacteremia in adult emergency department (ED) patients.METHODS: This cohort study included adult ED patients from a large urban, academic tertiary hospital, with blood cultures obtained within 24 h of admission between 2016 and 2017. The outcome measure was true bacteremia. NEWS, qSOFA, mSOFA, and the two versions of SF score were calculated for all patients based on the first available full set of vital signs within 2 h and laboratory values within 6 h after drawing the blood cultures. Area under the receiver operating characteristic curve (AUROC) was calculated for each scoring system.RESULTS: The study included 3106 ED patients, of which 199 (6.4%) patients had true bacteremia. The AUROCs for prediction of bacteremia were: NEWS = 0.65, qSOFA = 0.60, SF I = 0.65, mSOFA = 0.71, and SF II = 0.80.CONCLUSIONS: Scoring systems using only vital signs, NEWS, and SF I showed moderate abilities in predicting bacteremia, whereas qSOFA performed poorly. Scoring systems using both vital signs and laboratory values, mSOFA and especially SF II, showed good abilities in predicting bacteremia.

IntroductionEffective treatment of bloodstream infections (BSIs) is relying on rapid identification of the causing pathogen and its antibiotic susceptibility. Still, most commercially available antibiotic susceptibility testing (AST) methods are based on monitoring bacterial growth, thus impacting the time to results. The Resistell AST is based on a new technology measuring the nanomotion caused by physiologically active bacterial cells and detecting the changes in nanomotion caused by the exposure to a drug.Methods and analysisThis is a single-centre, prospective, cross-sectional, single-arm diagnostic accuracy study to determine the agreement of the Resistell AST on Gram-negative bacteria isolated from blood cultures among patients admitted to a tertiary-care hospital with the reference method. Up to 300 patients will be recruited. Starting with a pilot phase, enrolling 10%–20% of the subjects and limited toEscherichia coliBSI tested for ceftriaxone susceptibility, the main phase will follow, extending the study toKlebsiella pneumoniaeand ciprofloxacin.Ethics and disseminationThis study has received ethical approval from the Swiss Ethics Committees (swissethics, project 2020-01622). All the case report forms and clinical samples will be assigned a study code by the local investigators and stored anonymously at the reference centre (Lausanne University Hospital). The results will be broadly distributed through conference presentations and peer-reviewed publications.Trial registration numberClinicalTrials.gov Registry (NCT05002413).

The modified Duke criteria requires that Enterococcus faecalis bacteremia must be both community-acquired and without known focus in order to be considered a microbiological “Major” diagnostic criterion in the diagnosis of infective endocarditis. We believe that the microbiological diagnostic criteria should be updated to regard E. faecalis as a “typical” endocarditis bacterium as is currently the case, for example, viridans group streptococci and Staphylococcus aureus. Using data from a prospective study of 344 patients with E. faecalis bacteremia evaluated with echocardiography, we demonstrate that designating E. faecalis as a “typical” endocarditis pathogen, regardless the place of acquisition or the portal of entry, improved the sensitivity to correctly identify definite endocarditis from 70% (modified Duke criteria) to 96% (enterococcal adjusted Duke criteria).

Background Pseudomonas otitidis is a novel species of Pseudomonas bacteria that has been isolated from patients with otic infections. Case presentation In this report, we describe a case of a 59-year-old known with moderate chronic obstructive pulmonary disease with bronchiectasis and recurrent pneumonia where blood cultures revealed the growth of P. otitidis. Conclusions This case describes the first report of bacteraemia to P. otitidis and raises questions regarding the misdiagnosis and underestimation of the incidence of infections caused by this novel pathogen.

Background Stratification by clinical scores of patients suspected of infection can be used to support decisions on treatment and diagnostic workup. Seven clinical scores, SepsisFinder (SF), National Early Warning Score (NEWS), Sequential Orgen Failure Assessment (SOFA), Mortality in Emergency Department Sepsis (MEDS), quick SOFA (qSOFA), Shapiro Decision Rule (SDR) and Systemic Inflammatory Response Syndrome (SIRS), were evaluated for their ability to predict 30-day mortality and bacteraemia and for their ability to identify a low risk group, where blood culture may not be cost-effective and a high risk group where direct-from-blood PCR (dfbPCR) may be cost effective. Methods Retrospective data from two Danish and an Israeli hospital with a total of 1816 patients were used to calculate the seven scores. Results SF had higher Area Under the Receiver Operating curve than the clinical scores for prediction of mortality and bacteraemia, significantly so for MEDS, qSOFA and SIRS. For mortality predictions SF also had significantly higher area under the curve than SDR. In a low risk group identified by SF, consisting of 33% of the patients only 1.7% had bacteraemia and mortality was 4.2%, giving a cost of € 1976 for one positive result by blood culture. This was higher than the cost of € 502 of one positive dfbPCR from a high risk group consisting of 10% of the patients, where 25.3% had bacteraemia and mortality was 24.2%. Conclusion This may motivate a health economic study of whether resources spent on low risk blood cultures might be better spent on high risk dfbPCR.

Objectives Determination of pathogen-specific bacterial DNA load (BDL) in blood has been shown to be directly correlated with severity of infection in patients with bacteremia. In the diagnostic work-up of patients with Staphylococcus aureus bacteremia (SAB), determination of the primary focus is imperative, because of implications for treatment duration, and ultimately prognosis. Here we investigate whether measurement of BDL in patients with SAB can distinguish between intravascular and extravascular foci of infection. Methods In a consecutive cohort of 43 patients with positive blood cultures with Staphylococcus aureus, we performed a quantitative PCR on whole blood to detect the bacterial DNA load. Infections were classified into 3 categories: i) soft tissue infections and phlebitis, ii) deep-seated infections and iii) endocarditis and other intravascular infections. Bacterial DNA loads and inflammatory parameters in the three categories were analyzed and compared. Results Median BDL in patients with endocarditis and other intravascular infections was 1015 cfu/ml, significantly higher than BDL in the other two categories (28 and 31 cfu/ml respectively). In contrast, CRP and leukocytes were not significantly different between the three patient categories. BDL could be detected in all patients with intravascular causes and levels were generally 10–30 times higher than in the other infection categories. Median BDL in non-survivors was 85 cfu/ml, which was higher than in survivors with a median BDL of 29 cfu/ml, although not significant. Conclusions In Staphylococcus aureus bacteremia pathogen-specific BDL is distinctly higher in patients with intravascular infections compared to extravascular origins. As measurement of BDL by PCR can easily be implemented in routine diagnostics, it can improve the diagnostic work-up of SAB by rapidly identifying the subset of patients who need higher dosages of antibiotics and additional measures to improve outcome.

Background Staphylococcus aureus bacteremia (SAB) is frequently encountered in the hospital setting, and current guidelines recommend at least 14 days of antibiotic treatment for SAB in order to minimize risks of secondary deep infections and relapse. However, evidence to support these treatment recommendations remains scarce. Patients with uncomplicated SAB are known to have a low of risk of recurrence and death. Reducing treatment length in uncomplicated SAB would reduce the total consumption of antibiotics, duration of hospital admission, and potentially the risk of adverse events. With SAB7 we seek to determine if 7 days of antibiotic treatment in patients with uncomplicated SAB is non-inferior to 14 days of treatment. Methods/design The study is designed as a randomized, non-blinded, non-inferiority, multicenter interventional study. Primary measure of outcome will be 90-day survival without clinical or microbiological failure to treatment or relapse. Secondary outcomes include the prevalence of severe adverse effects, in particular secondary infection with Clostridium difficile, all-cause mortality, as well as public health related costs. Patients identified with uncomplicated SAB who have received 7 days of protocol-approved antibiotics will be eligible for inclusion and randomized 1:1 in two parallel arms to either (i) discontinue antibiotic treatment at day 7 or (ii) to continue antibiotic treatment for a total of 14 days. Main exclusion criteria include signs of complicated SAB, such as the presence of secondary deep infections, persistent bacteremia, and implantable devices. Patients are followed for 6 months with clinical examinations, consecutive blood tests, and registration of adverse events. A total of 284 patients are to be included at ten centers across Denmark. The primary endpoint will be tested with a statistical non-inferiority margin of 10 percentage points. Discussion SAB 7 will determine if 7 days of antibiotic treatment in patients with uncomplicated SAB is sufficient and safe. Results of the study will provide important knowledge on optimized SAB management and could potentially modify the current treatment recommendations. Trial registration ClinicalTrails.gov, H-17027414. Registered on May 2, 2018. The Danish Medicines Agency (EudraCT), 2017–003529-13. Registered on October 30, 2017. Electronic supplementary material The online version of this article (10.1186/s13063-019-3357-9) contains supplementary material, which is available to authorized users.

IntroductionMALDI-TOF MS represents a new technological era for microbiology laboratories. Improved sample processing and expanded databases have facilitated rapid and direct identification of microorganisms from some clinical samples. Automated analysis of protein spectra from different microbial populations is emerging as a potential tool for epidemiological studies and is expected to impact public health.AimTo demonstrate how implementation of MALDI-TOF MS has changed the way microorganisms are identified, how its applications keep increasing and its impact on public health and hospital hygiene.MethodsA review of the available literature in PubMED, published between 2009 and 2018, was carried out.ResultsOf 9,709 articles retrieved, 108 were included in the review. They show that rapid identification of a growing number of microorganisms using MALDI-TOF MS has allowed for optimisation of patient management through prompt initiation of directed antimicrobial treatment. The diagnosis of Gram-negative bacteraemia directly from blood culture pellets has positively impacted antibiotic streamlining, length of hospital stay and costs per patient. The flexibility of MALDI-TOF MS has encouraged new forms of use, such as detecting antibiotic resistance mechanisms (e.g. carbapenemases), which provides valuable information in a reduced turnaround time. MALDI-TOF MS has also been successfully applied to bacterial typing.ConclusionsMALDI-TOF MS is a powerful method for protein analysis. The increase in speed of pathogen detection enables improvement of antimicrobial therapy, infection prevention and control measures leading to positive impact on public health. For antibiotic susceptibility testing and bacterial typing, it represents a rapid alternative to time-consuming conventional techniques.

Objectives: Bacteria with common microbiological and clinical characteristics are often recognized as a particular group. The acronym HACEK stands for five fastidious genera associated with infective endocarditis (Haemophilus, Aggregatibacter, Cardiobacterium, Eikenella, and Kingella). Data on the epidemiology of HACEK are sparse. This article reports a 6-year nationwide study of HACEK bacteraemia in Denmark. Methods: Cases of HACEK bacteraemia occurring during the years 2010–2015 were retrieved from the national Danish microbiology database, covering an average surveillance population of 5.6 million per year. Results: A total of 147 cases of HACEK bacteraemia were identified, corresponding to an annual incidence of 0.44 per 100 000 population. The annual incidence for males was 0.56 per 100 000 and for females was 0.31 per 100 000. The median age was 56 years (range 0–97 years), with variation among the genera. One hundred and forty-three isolates were identified to the species level and six to the genus level: Haemophilus spp, n = 55; Aggregatibacter spp, n = 37; Cardiobacterium spp, n = 9; Eikenella corrodens n = 21; and Kingella spp, n = 27. Conclusions: This is the first study on the incidence of HACEK bacteraemia in a large surveillance population and may inspire further studies on the HACEK group. Haemophilus spp other than Haemophilus influenzae accounted for most cases of HACEK bacteraemia in Denmark, with Aggregatibacter spp in second place. Keywords: Epidemiology, Incidence, Age, Sex, Haemophilus, Aggregatibacter

We describe an outbreak of Burkholderia stabilis associated with contaminated washing gloves, a commercially available Class I medical device. Triggered by an increase in Burkholderia cepacia complex (BCC) bacteremias and the detection of BCC in unopened packages of washing gloves, an ad hoc national outbreak committee comprising representatives of a public health organisation, a regulatory agency, and an expert association convened and commissioned an outbreak investigation. The investigation included retrospective case finding across Switzerland and whole genome sequencing (WGS) of isolates from cases and gloves. The investigation revealed that BCC were detected in clinical samples of 46 cases aged 17 to 91 years (33% females) from nine institutions between May 2015 and August 2016. Twenty-two isolates from case patients and 16 from washing gloves underwent WGS. All available outbreak isolates clustered within a span of 1,500 alleles. This BCC outbreak was rapidly identified, communicated, investigated and halted by an ad hoc collaboration of multiple stakeholders. WGS served as useful tool for confirming the source of the outbreak. This outbreak also highlights current regulatory limitations regarding Class I medical devices and the usefulness of a nationally coordinated outbreak response.

BACKGROUND: Early identification of pathogens from blood cultures using matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) mass spectrometry may optimize the choice of empirical antibiotic therapy in the setting of bloodstream infections. We aimed to assess the impact of this new technology on the use of antibiotic treatment in patients with gram-negative bacteremia. METHODS: We conducted a prospective observational study from January to December 2010 to evaluate the sequential and separate impacts of Gram stain reporting and MALDI-TOF bacterial identification performed on blood culture pellets in patients with gram-negative bacteremia. The primary outcome was the impact of MALDI-TOF on empirical antibiotic choice. RESULTS: Among 202 episodes of gram-negative bacteremia, Gram stain reporting had an impact in 42 cases (20.8%). MALDI-TOF identification led to a modification of empirical therapy in 71 of all 202 cases (35.1%), and in 16 of 27 cases (59.3%) of monomicrobial bacteremia caused by AmpC-producing Enterobacteriaceae. The most frequently observed impact was an early appropriate broadening of the antibiotic spectrum in 31 of 71 cases (43.7%). In total, 143 of 165 episodes (86.7%) of monomicrobial bacteremia were correctly identified at genus level by MALDI-TOF. CONCLUSIONS: In a low prevalence area for extended spectrum betalactamases (ESBL) and multiresistant gram-negative bacteria, MALDI-TOF performed on blood culture pellets had an impact on the clinical management of 35.1% of all gram-negative bacteremia cases, demonstrating a greater impact than Gram stain reporting. Thus, MALDI-TOF could become a vital second step beside Gram stain in guiding the empirical treatment of patients with bloodstream infection.

BACKGROUNDIn 2015, Denmark launched an automated surveillance system for hospital-acquired infections, the Hospital-Acquired Infections Database (HAIBA).OBJECTIVETo describe the algorithm used in HAIBA, to determine its concordance with point prevalence surveys (PPSs), and to present trends for hospital-acquired bacteremiaSETTINGPrivate and public hospitals in DenmarkMETHODSA hospital-acquired bacteremia case was defined as at least 1 positive blood culture with at least 1 pathogen (bacterium or fungus) taken between 48 hours after admission and 48 hours after discharge, using the Danish Microbiology Database and the Danish National Patient Registry. PPSs performed in 2012 and 2013 were used for comparison.RESULTSNational trends showed an increase in HA bacteremia cases between 2010 and 2014. Incidence was higher for men than women (9.6 vs 5.4 per 10,000 risk days) and was highest for those aged 61–80 years (9.5 per 10,000 risk days). The median daily prevalence was 3.1% (range, 2.1%–4.7%). Regional incidence varied from 6.1 to 8.1 per 10,000 risk days. The microorganisms identified were typical for HA bacteremia. Comparison of HAIBA with PPS showed a sensitivity of 36% and a specificity of 99%. HAIBA was less sensitive for patients in hematology departments and intensive care units. Excluding these departments improved the sensitivity of HAIBA to 44%.CONCLUSIONSAlthough the estimated sensitivity of HAIBA compared with PPS is low, a PPS is not a gold standard. Given the many advantages of automated surveillance, HAIBA allows monitoring of HA bacteremia across the healthcare system, supports prioritizing preventive measures, and holds promise for evaluating interventions.Infect Control Hosp Epidemiol 2017;38:559–566

We report for the first time a case of bacteremia caused by Comamonas kerstersii in a 65-year-old patient with sign of diverticulosis. In addition, we review the isolation of Comamonas sp. and related organisms in our hospital over 25 years.

International audience; The increased incidence over the past decade of bloodstream infections (BSIs) caused by gram-positive bacteria, particularly methicillin-resistant Staphylococcus aureus, highlights the critical need for a consistent approach to therapy. However, there is currently no international consensus on the diagnosis and management of gram-positive BSIs. The Clinical Consensus Conference on Gram-Positive Bloodstream Infections was convened as a session at the 9th International Symposium on Modern Concepts in Endocarditis and Cardiovascular Infections held in 2007. Participants discussed various aspects of the practical treatment of patients who present with gram-positive BSI, including therapeutic options for patients with BSIs of undefined origin, the selection of appropriate empirical therapy, and treatment of complicated and uncomplicated BSIs. The opinions of participants about these key issues are reflected in this article.

Hospital antibiotic consumption is generally adjusted to occupancy. This study hypothesised that the number of blood culture samples could be a surrogate marker for case-mix adjustment. Antibiotic consumption was compared over 16 consecutive trimesters in one medical ward in terms of patient-days or blood culture samples. Compared with patient-days, measurement adjusted to blood culture samples detected three trimesters with an unusually high consumption, and one trimester with consumption falsely classified as high because of a high incidence of infections. Blood culture numbers enabled easy and accurate identification of periods with a drift in antibiotic consumption in a medical ward.