Management and outcome of bloodstream infections: a prospective survey in 121 French hospitals (SPA-BACT survey)

The utility of temporal trends of blood biomarkers as predictors for bloodstream infections in left ventricular assist device recipients

BACKGROUND

Temporal trends of routinely obtained parameters may provide valuable information for predicting BSIs, but this association has not yet been established in LVAD patients.

METHODS

This retrospective analysis included data from 347 consecutive recipients of three rotary LVAD types. Study endpoints included the incidence of BSI, the association of temporal trends of routinely obtained blood biomarkers with the development of BSIs, the incidence of BSIs, and survival on LVAD support.

RESULTS

During follow-up, 47.8% (n = 166) of the patients developed BSI. In multivariate analyses, the development of BSI was a significant predictor of mortality (HR 5.78, 95% CI 4.08-8.19, p < 0.0001). In univariate analyses, after adjusting for potential confounders, albumin (SHR 0.94, 95% CI 0.91-0.97, p < 0.00010), creatinine (SHR 1.49, 95% CI 1.03-2.15, p = 0.033), and C-reactive protein (SHR 1.19, 95% CI 1.08-1.32, p = 0.0007) significantly predicted the development of BSIs during LVAD support. Notably, the strength of the association of parameter changes with the prediction of BSIs demonstrated a time-dependent correlation in the cases of albumin (p = 0.045) and creatinine (p = 0.003).

CONCLUSION

Bloodstream infections are highly prevalent among LVAD recipients and are independent predictors of mortality. Temporal biomarker trends significantly predict the development of BSIs. These findings suggest opportunities for interventions aiming to reduce the incidence of BSIs.

Clinical impact and cost-consequence analysis of ePlex® blood culture identification panels for the rapid diagnosis of bloodstream infections: a single-center randomized controlled trial

To assess clinical impact and perform cost-consequence analysis of the broadest multiplex PCR panels available for the rapid diagnosis of bloodstream infections (BSI). Single-center, randomized controlled trial conducted from June 2019 to February 2021 at a French University hospital with an institutional antimicrobial stewardship program. Primary endpoint was the percentage of patients with optimized antimicrobial treatment 12 h after transmission of positivity and Gram stain results from the first positive BC. This percentage was significantly higher in the multiplex PCR (mPCR) group (90/105 = 85.7% %, CI95% [77.5 ; 91.8] vs. 68/107 = 63.6%, CI95% [53.7 ; 72.6]; p < 10- 3) at interim analysis, resulting in the early termination of the study after the inclusion of 309 patients. For patients not optimized at baseline, the median time to obtain an optimized therapy was much shorter in the mPCR group than in the control group (6.9 h, IQR [2.9; 17.8] vs. 26.4 h, IQR [3.4; 47.5]; p = 0.001). Early optimization of antibiotic therapy resulted in a non-statistically significant decrease in mortality from 12.4 to 8.8% (p = 0.306), with a trend towards a shorter median length of stay (18 vs. 20 days; p = 0.064) and a non-significant reduction in the average cost per patient of €3,065 (p = 0.15). mPCR identified all the bacteria present in 88% of the samples. Despite its higher laboratory cost, the use of multiplex PCR for BSI diagnosis leads to early-optimised therapy, seems cost-effective and could reduce mortality and length of stay. Their impact could probably be improved if implemented 24/7.

The Molecular Mouse System: A New Useful Tool for Guiding Antimicrobial Therapy in Critically Ill Septic Patients

Bloodstream infections (BSI) caused by multidrug-resistant (MDR) bacteria, pose a major threat for patients, especially for those who are immunosuppressed. Rapid pathogen detection and characterization from positive blood cultures are crucial in the management of patients with BSI to enable an adequate and timely antimicrobial therapy. This study aimed to investigate the potential role of the Molecular Mouse system, a new CE IVD molecular test designed to rapidly detect the causative agents of bacteremia and their resistance determinants, in the management of the therapy in critically ill patients. Agreement between the results of the Molecular Mouse and the conventional routine method was also considered. Overall, 100 positive blood cultures were collected from septic critically ill patients from May 2023 to January 2024 and analyzed with Molecular Mouse and routine protocols. The new instrument consistently agreed with the routine protocols in the case of monomicrobial blood cultures, while some discrepancies were obtained in the polymicrobial samples. Antimicrobial resistance genes were detected in 35 samples, with vanA and CTX-M-1/9 groups being the most frequently detected targets. Therapy was adjusted in 42 critically ill patients confirming the importance of new rapid molecular tests in the management of positive blood cultures, to adjust empirical therapy and use new antibiotics accurately.

Rapid determination of antimicrobial susceptibility of Gram-negative bacteria from clinical blood cultures using a scattered light-integrated collection device

Background. A bloodstream infection (BSI) presents a complex and serious health problem, a problem that is being exacerbated by increasing antimicrobial resistance (AMR).Gap Statement. The current turnaround times (TATs) for most antimicrobial susceptibility testing (AST) methods offer results retrospective of treatment decisions, and this limits the impact AST can have on antibiotic prescribing and patient care. Progress must be made towards rapid BSI diagnosis and AST to improve antimicrobial stewardship and reduce preventable deaths from BSIs. To support the successful implementation of rapid AST (rAST) in hospital settings, a rAST method that is affordable, is sustainable and offers comprehensive AMR detection is needed.Aim. To evaluate a scattered light-integrated collection (SLIC) device against standard of care (SOC) to determine whether SLIC could accelerate the current TATs with actionable, accurate rAST results for Gram-negative BSIs.Methods. Positive blood cultures from a tertiary referral hospital were studied prospectively. Flagged positive Gram-negative blood cultures were confirmed by Gram staining and analysed by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry, Vitek 2, disc diffusion (ceftriaxone susceptibility only) and an SLIC device. Susceptibility to a panel of five antibiotics, as defined by European Committee on Antimicrobial Susceptibility Testing breakpoints, was examined using SLIC.Results. A total of 505 bacterial-antimicrobial combinations were analysed. A categorical agreement of 95.5 % (482/505) was achieved between SLIC and SOC. The 23 discrepancies that occurred were further investigated by the broth microdilution method, with 10 AST results in agreement with SLIC and 13 in agreement with SOC. The mean time for AST was 10.53±0.46 h and 1.94±0.02 h for Vitek 2 and SLIC, respectively. SLIC saved 23.96±1.47 h from positive blood culture to AST result.Conclusion. SLIC has the capacity to provide accurate AST 1 day earlier from flagged positive blood cultures than SOC. This significant time saving could accelerate time to optimal antimicrobial therapy, improving antimicrobial stewardship and management of BSIs.

Microbiological Assessment of the FilmArray Blood Culture Identification 2 Panel: Potential Impact in Critically Ill Patients

Rapid pathogen detection and characterization from positive blood cultures are crucial in the management of patients with bloodstream infections (BSI) and in achieving their improved outcomes. In this context, the FilmArray Blood Culture Identification (BCID2) panel is an FDA approved molecular test, which can quickly identify different species and resistance determinants, thus making an impact in antimicrobial practice. In this study, we analyzed 136 positive blood cultures collected from septic critically ill patients from April 2021 to March 2023 by using the FilmArray BCID2 panel, and results obtained by fast molecular analysis were compared to those obtained by routine protocols. Overall, the BCID2 panel showed a strong concordance with conventional methods, particularly in the case of monomicrobial samples, whereas some discrepancies were found in 10/32 polymicrobial samples. Of note, this technique allowed us to identify a significant number of yeasts (37/94 samples) and to unravel the presence of several resistance markers, including both Gram-positive and Gram-negative organisms. These findings strongly support the potential use of the BCID2 panel as an adjunct to the conventional microbiology methods for the management of critically ill septic patients, thus accelerating blood pathogen and resistance genes identification, focusing antibiotic therapy, and avoiding inappropriate and excessive use of drugs.

Shortening identification times: comparative observational study of three early blood culture testing protocols

Background

While early appropriate antibiotic therapy is a proven means of limiting the progression of infections, especially bacteremia, empirical antibiotic therapy in sepsis is ineffective up to 30%. The aim of this study was to compare early blood culture testing protocols in terms of their ability to shorten the delay between blood sampling and appropriate antibiotic therapy.

Methods

In this french observational study, we compared three blood culture testing protocols. Positive blood cultures were tested using either GenMark ePlex panels (multiplex PCR period), a combination of MRSA/SA PCR, β-Lacta and oxidase tests (multitest period), or conventional identification and susceptibility tests only (reference period). Conventional identification and susceptibility tests were performed in parallel for all samples, as the gold standard.

Results

Among the 270 patients with positive blood cultures included, early and conventional results were in good agreement, especially for the multitest period. The delay between a blood culture positivity and initial results was 3.8 (2.9-6.9) h in the multiplex PCR period, 2.6 (1.3-4.5) h in the multitest period and 3.7 (1.8-8.2) h in the reference period (p<0.01). Antibiotic therapy was initiated or adjusted in 68 patients based on early analysis results. The proportion of patients receiving appropriate antibiotic therapy within 48 h of blood sampling was higher in the multiplex PCR and multitest periods, (respectively 90% and 88%) than in the reference period (71%).

Conclusion

These results suggest rapid bacterial identification and antibiotic resistance tests are feasible, efficient and can expedite appropriate antibiotic therapy.

Clinical outcome of rapid diagnosis and antibiotic stewardship in patients with bloodstream infection in Lampang Hospital

Bloodstream infection is a significant cause of morbidity and mortality. Early diagnosis and appropriate antibiotic treatment contribute to a favorable prognosis. We demonstrate a reduction of time to proper antibiotics and reduced mortality utilizing prompt diagnosis and antibiotic stewardship by infectious diseases physicians at a general hospital in Thailand.

Bloodstream infection in hospital therapeutic patients

Bloodstream infection (BI) is the cause of high mortality. Hospital bloodstream infection (HBI) complicates hemodialysis, pneumonia, oncohematological diseases. Positive hemoculture obtaining depends on the volume of blood inoculation, the number of blood samples, the incubation time. To test the principles of microbiological culturomics in the diagnosis BI of hospital patients with a therapeutic profile. 848 hospital cardiac patients with suspected BI were included. 10 ml of blood were taken intravenously with a syringe, blood was inoculated into 200 ml of the heart-brain medium (HBM) in an anaerobic bottle. It was incubated for 7 or more days in a thermostat at +37º C. The hemocultures were obtained in 64.3% of cases with paired blood sampling with an interval of 30 minutes whereas an increase in the number of blood samples reduced the effectiveness of obtaining hemocultures to 9.1%. When incubating bottles for more than 7 days there were obtained 200 additional hemocultures containing 239 strains of microorganisms. Episodes of HBI were observed more often in the cases of the circulatory system (77.8%), including infectious endocarditis (IE) (47.0%), rheumatism (22.1%), myocarditis (14.6%). Episodes of HBI occurred more often in men with IE and coronary heart disease, in women - with rheumatism and myocarditis. Patients aged 45-75 were in the group of risk with a probability of complications of HBI up to 73.7%. When examining the blood of 848 hospital patients of cardiological profile HBI was detected in 38.3% of cases. Among clinical isolates gram-positive cocci with a great number S.epidermidis prevailed. Polymicrobial hemocultures (16.3%) were characterized by two and three associates in one blood sample. Among the hematological indicators in HBI there were: leukocytosis, increased ESR, lymphocytosis, decreased hemoglobin; increased values of fibrinogen, CRP, γ-globulin, α2-globulin, low levels of total protein and A/G coefficient. The techniques of microbiological culturomics were used. HBI was diagnosed in 38.3% of the therapeutic patients of cardiological profile. The etiology of HBI was characterized by polymicrobicity in 16.3% of cases. Hematological markers of HBI were identified.

The transition between acute and chronic infections in light of energy control: a mathematical model of energy flow in response to infection

BACKGROUND

Different parts of an organism like the gut, endocrine, nervous and immune systems constantly exchange information. Understanding the pathogenesis of various systemic chronic diseases increasingly relies on understanding how these subsystems orchestrate their activities.

METHODS

We started from the working hypothesis that energy is a fundamental quantity that governs activity levels of all subsystems and that interactions between subsystems control the distribution of energy according to acute needs. Based on physiological knowledge, we constructed a mathematical model for the energy flow between subsystems and analysed the resulting organismal responses to in silico infections.

RESULTS

The model reproduces common behaviour in acute infections and suggests several host parameters that modulate infection duration and therapeutic responsiveness. Moreover, the model allows the formulation of conditions for the induction of chronic infections and predicts that alterations in energy released from fat can lead to the transition from clearance of acute infections to a chronic inflammatory state.

IMPACT

These results suggest a fundamental role for brain and fat in controlling immune response through systemic energy control. In particular, it suggests that lipolysis resistance, which is known to be involved in obesity and ageing, might be a survival programme for coping with chronic infections.

Cost-utility analysis of antimicrobial stewardship programme at a tertiary teaching hospital in Ethiopia

OBJECTIVE

Antimicrobial stewardship (AMS) significantly reduces inappropriate antibiotic use and improves patient outcomes. In low-resource settings, AMS implementation may require concurrent strengthening of clinical microbiology capacity therefore additional investments. We assessed the cost-effectiveness of implementing AMS at Tikur Anbessa Specialised Hospital (TASH), a tertiary care hospital in Ethiopia.

DESIGN

We developed a Markov cohort model to assess the cost-utility of pharmacist-led AMS with concurrent strengthening of laboratory capacity compared with usual care from a 'restricted societal' perspective. We used a lifetime time horizon and discounted health outcomes and cost at 3% annually. Data were extracted from a prospective study of bloodstream infections among patients hospitalised at TASH, supplemented by published literature. We assessed parameter uncertainty using deterministic and probabilistic sensitivity analyses.

SETTING

Tertiary care hospital in Ethiopia, with 800 beds and serves over half a million patients per year.

POPULATION

Cohort of adults and children inpatient population aged 19.8 years at baseline.

INTERVENTION

Laboratory-supported pharmacist-led AMS compared with usual care. Usual care is defined as empirical initiation of antibiotic therapy in the absence of strong laboratory and AMS.

OUTCOME MEASURES

Expected life-years, quality-adjusted life-years (QALYs), costs (US$2018) and incremental cost-effectiveness ratio.

RESULTS

Laboratory-supported AMS strategy dominated usual care, that is, AMS was associated with an expected incremental gain of 38.8 QALYs at lower expected cost (incremental cost savings:US$82 370) per 1000 patients compared with usual care. Findings were sensitive to medication cost, infection-associated mortality and AMS-associated mortality reduction. Probabilistic sensitivity analysis demonstrated that AMS programme was likely to be cost-effective at 100% of the simulation compared with usual care at 1%-51% of gross domestic product/capita.

CONCLUSION

Our study indicates that laboratory-supported pharmacist-led AMS can result in improved health outcomes and substantial healthcare cost savings, demonstrating its economic advantage in a tertiary care hospital despite greater upfront investments in a low-resource setting.

Computerized decision support system (CDSS) use for surveillance of antimicrobial resistance in urinary tract infections in primary care

BACKGROUND

Hospital-based surveillance of antimicrobial resistance may be irrelevant as a guide to antimicrobial use for urinary tract infections (UTIs) in primary care.

OBJECTIVES

To highlight the value of online computerized decision support systems (CDSS) in providing information on the surveillance of antimicrobial resistance in community-acquired UTIs.

METHODS

We collected the susceptibility profile for key antibiotics by type of UTI involving Escherichia coli from 2017 to 2020, using queries for UTI (Q-UTI) submitted to a French CDSS. We compared these results with those from the MedQual French surveillance system for community-acquired UTI and the European Antimicrobial Resistance Surveillance Network (EARS-NET) for invasive infections.

RESULTS

We collected 43 591 Q-UTI, of which 10 192 (23%) involved E. coli: 40% cystitis, 32% male-UTI, and 27% pyelonephritis. Resistance was 41.3% (95% CI, 40.3%-42.2%) for amoxicillin, 16.6% (95% CI, 15.9%-17.3%) for fluoroquinolones, 6.6% (95% CI, 6.1%-7.0%) for third-generation cephalosporins (3GC), and 5.7% (95% CI, 5.2%-6.1%) for aminoglycosides. Resistance to amoxicillin was lower than that reported in MedQual (42.7%, P value = 0.004), and in EARS-NET (55.2%, P value < 0.001). For fluoroquinolones, resistance was higher than in MedQual (12.0%, P value < 0.001) and EARS-NET (15.8%, P value = 0.041). In complicated pyelonephritis and male UTI, fluoroquinolone resistance peaked at ∼20%. For 3GC, all UTI had higher resistance than in MedQual (3.5%, P value < 0.001), but lower than in EARS-NET (9.5%, P value < 0.001). Aminoglycoside resistance was not reported by MedQual, and was lower than in EARS-NET (7.1%, P value < 0.001).

CONCLUSIONS

CDSS can inform prescribers in real-time about the ecology and surveillance of E. coli resistance in community-acquired UTI. In complicated upper UTIs, they can underline the risk of empirical use of fluoroquinolones and suggest preferential use of 3GC.

Appropriateness of empirical antibiotic prescription for bloodstream infections in an emergency department from 2006 to 2018: impact of the spread of ESBL-producing Enterobacterales

The spread of ESBL producers in the community may impact the management of patients with bloodstream infections (BSI) involving Enterobacterales in emergency departments. Thus, from 2006 to 2018, data for all BSI episodes involving Enterobacterales from the emergency department of a French teaching hospital were retrospectively included. Antimicrobial susceptibility test results and empirical antibiotic regimens were recorded. Treatment was considered as appropriate if all isolates were susceptible in vitro to at least one prescribed antibiotic. A total of 1369 BSI episodes in 1321 patients was included. Urinary tract infection was the main source of BSI (61%). The prevalence of ESBL producers increased from zero to 9.2/100 Enterobacterales BSI cases (p < 0.001), mainly Escherichia coli (6.9 cases/100 BSI in 2018); and no Klebsiella. Third-generation cephalosporins (3GC) were used most frequently (71.8%) and their use as monotherapy increased during the study period (p < 0.001). The rate of appropriate treatment decreased from 95.8 to 89.2% (p = 0.023). Appropriateness of treatment was greater using two drugs vs one (97.3% vs 89.3%, p < 0.001). Treatments with 3GC were appropriate in 92% and 98.3%, when used alone or with another antibiotic, respectively (p < 0.001). Among inappropriate treatments, 45% concerned 3GC, with 74.6% of them attributable to ESBL production. The spread of ESBL producers in the community had a direct impact on the rate of inappropriate empirical treatment. Local antimicrobial resistance monitoring is required to optimize the management of BSI in emergency departments.

Comparison of novel approaches for expedited pathogen identification and antimicrobial susceptibility testing against routine blood culture diagnostics

Blood stream infections pose a major challenge for clinicians as the immediate application of an appropriate antibiotic treatment is the vital factor to safe the patients' lives. This preliminary study compares three different systems promising fast pathogen identification and susceptibility testing in comparison to conventional blood culture (BC): (i) the rapid antimicrobial susceptibility testing protocol according to EUCAST in combination with the Sepsityper^® kit (sRAST), (ii) the direct inoculation method on the VITEK^®2 system (dVIT) and (iii) testing with the Accelerate Pheno^® system (AccPh). All methods were assessed in terms of accuracy, time to result and usability. Twenty‐three BC samples obtained from patients suffering from proven sepsis were analysed in detail. Pathogen identification was successful in 95·6, 91·3 and 91·3% in sRAST, dVIT and AccPh, respectively. Categorical agreement in antimicrobial susceptibility testing was 89·5, 96 and 96·6%, respectively. Time to result from sample entry to reporting ranged from an average of 4·6 h for sRAST and 6·9 h for AccPh to 10·6 h for dVIT. These results imply a significant shortening of reporting times at considerably high agreement rates for these new diagnostic approaches.

Bloodstream infections in older population: epidemiology, outcome, and impact of multidrug resistance

Bloodstream infections (BSIs) among older patients are frequent with high rate of mortality. Infections with multidrug-resistant organisms (MDRO) are associated with higher mortality than with susceptible microorganisms. We aimed to evaluate the prevalence of MDRO infection during BSI in older population and the factors associated with unfavorable outcome. This study is a retrospective cohort of all BSI episodes occurring among older patients (> 65yo), from April 1, 2010, to December 31, 2016, in a French university hospital for geriatric medicine. A total of 255 BSI episodes were analyzed. Mean age was 86.3±6.5 years, and sex ratio (M/F) was 0.96. Main comorbidities were orthopedic device (26.7%), active neoplasia (24.3%), and diabetes mellitus (18.4%). Main primary sites of infection were urinary tract infections (56.9%), respiratory tract infections (10.6%), intra-abdominal infections (7.1%), and skin and soft tissue infections (4.7%). Main bacteria identified were Escherichia coli (45.1%), Staphylococcus aureus (14.1%), enterococci (10.7%), coagulase-negative staphylococci (CoNS) (5.5%), and streptococci (5.1%). MDROs were involved in 17.2% of BSI (gram-negative bacilli: 9.0%; CoNS: 4.3%; and methicillin-resistant S. aureus (MRSA): 3.9%). The main factor associated with MDRO BSI was colonization with MDRO (OR=6.29; 95%CI=2.9-14.32). Total mortality was 18.4% and significantly higher in case of initial severity (OR=3.83; 95%CI=1.75-8.38), healthcare-associated infection (OR=5.29; 95%CI=1.11-25.30), and MRSA BSI (OR=9.16; 95%CI=1.67-50.16). BSI due to MDRO is frequent in older population and is strongly associated with carriage of MDRO. Healthcare-associated BSI, severe episodes, and BSI due to MRSA are associated with unfavorable outcome. In these cases, a broad-spectrum antibiotic should be promptly initiated.

Evaluation of Microbiological Performance and the Potential Clinical Impact of the ePlex® Blood Culture Identification Panels for the Rapid Diagnosis of Bacteremia and Fungemia

Molecular rapid diagnostic assays associated with antimicrobial stewardship have proven effective for the early adaptation of empiric therapy in bloodstream infections. The ePlex^® BCID (GenMark Diagnostics) Panels allow identification of 56 bacteria and fungi and 10 resistance genes in 90 min directly from positive blood cultures. We prospectively evaluated 187 sepsis episodes at Grenoble University Hospital and retrospectively analyzed the cases to measure the potential clinical impact of the ePlex BCID results. Identification of all pathogens was obtained for 164/187 (88%) bloodstream infections with 100% detection of antimicrobial resistance genes (17 bla_CTX-M , 1 vanA, and 17 mecA genes). Only 15/209 (7%) strains were not covered by the panels. Sensitivity for detection of micro-organisms targeted by the RUO BCID-GP, BCID-GN, and BCID-FP Panels was respectively 84/84 (100%), 103/107 (96%), and 14/14 (100%). Interestingly, accurate identification of all pathogens was achieved in 15/17 (88%) polymicrobial samples. Retrospective analysis of medical records showed that a modification of antimicrobial treatment would have been done in 45% of the patients. Treatment modifications would have been an optimization of empiric therapy, a de-escalation or an escalation in respectively 16, 17, and 11% of the patients. Moreover, 11% of the samples were classified as contaminants or not clinically relevant and would have led to early de-escalation or withdrawal of any antibiotic. Detection of resistance genes in addition to identification alone increased escalation rate from 4 to 11% of the patients. Absence of the ePlex result was considered a lost opportunity for therapy modification in 28% of patients.

Combination Therapy with Aminoglycoside in Bacteremiasdue to ESBL-Producing Enterobacteriaceae in ICU

Objectives: Evaluation of the efficacy of empirical aminoglycoside in critically ill patients with bloodstream infections caused by extended-spectrum β-lactamase producing Enterobacteriaceae (ESBL-E BSI). Methods: Patients treated between 2011 and 2018 for ESBL-E BSI in the ICU of six French hospitals were included in a retrospective observational cohort study. The primary endpoint was mortality on day 30. Results: Among 307 patients, 169 (55%) were treated with empirical aminoglycoside. Death rate was 40% (43% with vs. 39% without aminoglycoside, p = 0.55). Factors independently associated with death were age ≥70 years (OR: 2.67; 95% CI: 1.09–6.54, p = 0.03), history of transplantation (OR 5.2; 95% CI: 1.4–19.35, p = 0.01), hospital acquired infection (OR 8.67; 95% CI: 1.74–43.08, p = 0.008), vasoactive drugs >48 h after BSI onset (OR 3.61; 95% CI: 1.62–8.02, p = 0.001), occurrence of acute respiratory distress syndrome (OR 2.42; 95% CI: 1.14–5.16, p = 0.02), or acute renal failure (OR 2.49; 95% CI: 1.14–5.47, p = 0.02). Antibiotherapy appropriateness was more frequent in the aminoglycoside group (91.7% vs. 77%, p = 0.001). Rate of renal impairment was similar in both groups (21% vs. 24%, p = 0.59). Conclusions: In intensive care unit (ICU) patients with ESBL-E BSI, empirical treatment with aminoglycoside was frequent. It demonstrated no impact on mortality, despite increasing treatment appropriateness.

Updates on Rapid Diagnostic Tests in Infectious Diseases

In the last two decades there have been dramatic advances in development of rapid diagnostic tests. Turnaround time of the assays have significantly been shortened which led to reductions in time to appropriate antimicrobial therapy and improvement of patient clinical outcomes. Molecular-based assays generally have better sensitivity than conventional methods, but the cost is higher. The results need to be interpreted cautiously as detection of colonized organisms, pathogen detection in asymptomatic patients, and false negative/positive can occur. Indications and cost-effectiveness need to be considered for appropriate utilization of rapid diagnostic tests.

Burden of bacterial bloodstream infection-a brief update on epidemiology and significance of multidrug-resistant pathogens

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.