Catheter-related bloodstream infection caused by Enterococcus spp

Vascular Access Device Infections: Current Management Practices and the Role of Multidisciplinary Teams at a Large Hospital in Northern Italy

Introduction: Vascular access device (VAD)-associated infections, including catheter-related (CRBSI) and catheter-associated bloodstream infections (CABSI), present significant challenges in patient care. While multidisciplinary VAD teams (VATs) are equipped with protocols for managing these infections, adherence to these guidelines in real-life practice is inconsistent. This study aims to evaluate the alignment between actual VAD infection management practices and VAT-recommended protocols. Methods: We conducted a retrospective, single-center study at Luigi Sacco Hospital (May 2021-October 2023) involving non-ICU adult patients with diagnosed CRBSI or CABSI. VAT experts independently reviewed infection management choices, which were divided into eight specific procedural options. These options included variations in VAD removal, timing of repositioning, and combinations of antimicrobial lock therapy and systemic therapy. Concordance between real-life practices and VAT recommendations was evaluated using Cohen's kappa coefficient. Results: Of 2419 VAD placements, 146 (6%) developed infections (84 CABSI, 62 CRBSI). Clinicians removed VADs in 66.4% of cases compared to 62.3% per VAT recommendations, with moderate overall agreement (Cohen's kappa = 0.58). Analysis of the eight management categories revealed moderate to low alignment (unweighted kappa = 0.44, weighted kappa = 0.30) between real-life practices and VAT guidance, with slightly improved concordance in CRBSI cases. Conclusions: Our findings underscore a discrepancy between real-life VAD infection management and VAT-recommended protocols, suggesting a need for clearer, more accessible guidelines and increased multidisciplinary collaboration. Enhanced VAT consultation and simplified protocol dissemination may improve consistency in infection management and ultimately lead to better patient outcomes.

Enterococcus faecalis suppresses Staphylococcus aureus-induced NETosis and promotes bacterial survival in polymicrobial infections

Enterococcus faecalis is an opportunistic pathogen that is frequently co-isolated with other microbes in wound infections. While E. faecalis can subvert the host immune response and promote the survival of other microbes via interbacterial synergy, little is known about the impact of E. faecalis-mediated immune suppression on co-infecting microbes. We hypothesized that E. faecalis can attenuate neutrophil-mediated responses in mixed-species infection to promote survival of the co-infecting species. We found that neutrophils control E. faecalis infection via phagocytosis, ROS production, and degranulation of azurophilic granules, but it does not trigger neutrophil extracellular trap formation (NETosis). However, E. faecalis attenuates Staphylococcus aureus-induced NETosis in polymicrobial infection by interfering with citrullination of histone, suggesting E. faecalis can actively suppress NETosis in neutrophils. Residual S. aureus-induced NETs that remain during co-infection do not impact E. faecalis, further suggesting that E. faecalis possess mechanisms to evade or survive NET-associated killing mechanisms. E. faecalis-driven reduction of NETosis corresponds with higher S. aureus survival, indicating that this immunomodulating effect could be a risk factor in promoting the virulence polymicrobial infection. These findings highlight the complexity of the immune response to polymicrobial infections and suggest that attenuated pathogen-specific immune responses contribute to pathogenesis in the mammalian host.

Randomised, open-label, non-inferiority clinical trial on the efficacy and safety of a 7-day vs 14-day course of antibiotic treatment for uncomplicated enterococcal bacteraemia: the INTENSE trial protocol

INTRODUCTION

Enterococcus spp is responsible for 8%-15% of total bacteraemias with an associated global mortality around 23%-30%. Regarding the clinical management of enterococcal bacteraemia, the evidence on the duration of antibiotic treatment is scarce and the studies do not discriminate between complicated and uncomplicated bacteraemia.

METHODS

The INTENSE study is a multicentre, open-label, randomised, pragmatic, phase-IV clinical trial to demonstrate the non-inferiority of a 7-day vs 14-day course for the treatment of uncomplicated enterococcal bacteraemia and incorporating the early switching to oral antibiotics when feasible. The primary efficacy endpoint is the clinical cure at day 30±2 after the end of the treatment. Secondary endpoints will include the rate of relapse or infective endocarditis, length of stay, duration of intravenous therapy, Clostridioides difficile infection and the evaluation of the safety of both treatment arms through the recording and analysis of adverse events. For a 6% non-inferiority margin and considering a 5% withdrawal rate, 284 patients will be included.

ANALYSIS

The difference in proportions with one-sided 95% CIs will be calculated for the clinical cure rate using the control group as reference. For secondary categorical endpoints, a similar analysis will be performed and Mann-Whitney U-test will be used to compare median values of quantitative variables. A superiority analysis applying the response adjusted for days of antibiotic risk will be performed if there were incidents in recruitment; will allow obtaining results with 194 patients recruited.

ETHICS AND DISSEMINATION

The study has obtained the authorisation from the Spanish Regulatory Authority, the approval of the ethics committee and the agreement of the directors of each centre. Data will be published in peer-reviewed journals.

TRIAL REGISTRATION NUMBER

NCT05394298.

Scanning Electron Microscope Examination as an Alternative to Classical Microbiology in the Diagnostics of Catheter-Related Sepsis?

Central venous catheters are essential elements enabling the treatment of intensive care unit patients. However, these catheters are sometimes colonised by both bacteria and fungi, and thus, they may become a potential source of systemic infections-catheter-related bloodstream infections (CRBSI). The identification of the pathogen responsible for CRBSI is a time-consuming process. At the same time, the relationship between the quick identification of the pathogen and the implementation of targeted antibiotic therapy is of key importance for controlling the clinical symptoms of sepsis and septic shock in the patient. Quick diagnosis is of key importance to reduce morbidity and mortality in this group of patients. In our study, we attempted to create a catalogue of images of the most commonly cultured pathogens responsible for CRBSI. An FEI Quanta 250 FEG Scanning Electron Microscope (SEM) was used for measurements. SEM images obtained during the analysis were included in this study. Images of SEM are three-dimensional and comparable to the images seen with the human eye and are a tool used for research and measurement whenever it is necessary to analyse the state of the surface and assess its morphology. The method described in our study will not replace the current procedures recognised as the gold standard, i.e., pathogen culturing, determination of the count of microorganisms (CFU -colony forming units), and assessment of drug sensitivity. However, in some cases, the solution proposed in our study may aid the diagnosis of patients with suspected catheter-related bloodstream infections leading to sepsis and septic shock.

Treatment duration for central line-associated infection caused by Enterococcus spp.: a retrospective evaluation of a multicenter cohort

Objective of this study was to assess the appropriate treatment duration for enterococcal central line-associated bloodstream infections (CLABSIs). This observational, retrospective, multicenter study conducted between 2011 and 2019 enrolled all hospitalized patients with monomicrobial enterococcal CLABSI. Those with infective endocarditis and non-survivors at least 7 days from index blood culture (BC) were excluded. Primary endpoint was 30-day mortality. We enrolled 113 patients, of whom 59% were male, median age was 64 (SD ± 15) and median Charlson's index score 5 (IQR 3-8). Enterococcus faecalis and Enterococcus faecium were found in 51% and 44% of cases, respectively. Median treatment duration was 11 days (IQR 6-17), and 32% of patients (n = 36) received ≤ 7 days. Characteristics of patients receiving more or less than 7 days of treatment were similar. Central line was removed in 82% (n = 93) of cases within a median of 3 days (1-8). At both uni- and multivariate analysis, duration of antibiotic treatment > 7 days was not associated with 30-day mortality [HR 0.41 (95% CI, 0.13-1.24), p = 0.12] even after adjustment with propensity score [HR 0.47 (95% CI 0.17-1.26), p = 0.13]. A 7-day treatment course appears to be safe in non-complicated enterococcal CLABSIs.

Atomic force microscopy and scanning electron microscopy as alternative methods of early identification of pathogens causing catheter-related bloodstream infections of patients in ICU

Introduction

Vascular catheters are an indispensable element of the therapy of patients in intensive care. Their use is associated with the possibility of complications, including infectious. According to various sources, the incidence of catheter-related bloodstream infections (CRBSIs) ranges from 0.1 to 22.7 per 1,000 catheter days.

Materials and Methods

The central venous catheter tip culture samples were collected from 24 patients with suspected catheter-related bloodstream infection, from three intensive care units (ICUs). The results of microscopic examinations: atomic force microscope (AFM) and scanning electron microscope (SEM) were compared with the results of microbiological analysis of the central venous catheter tip and blood collected from the catheter.

Results

The microscopic examination and microbiological analysis of both the blood and central venous catheter samples confirmed the presence of microorganisms in 16 cases (double positive result). Our study was conducted in a short period of time (up to 6 hours) and it gave an initial answer to the question about the type of microorganisms colonising the central venous catheter. In one patient the infection was not caused by removal of the central venous catheter. However, not all results were fully consistent within the two diagnostic methods. The colonisation of the central venous catheter with Pseudomonas aeruginosa and Staphylococcus epidermidis was microbiologically confirmed, but it was not confirmed by the microscopic examination of the sample collected from patient No. 20. However, the examination enabled preliminary assessment of the microorganism colonising the catheter, which may have caused the blood infection. It cannot be ruled out that Pseudomonas aeruginosa bacilli were grown on the catheter that came into contact with blood from another source of infection, e.g. the respiratory, nervous or urinary systems. Information on the presence of cocci-shaped bacteria forming characteristic clusters or rods may enable initial diagnosis of catheter-related bloodstream infection if it is accompanied by typical clinical symptoms. Alternative diagnostics also provides valuable information on the presence of biofilm, which is a factor hindering the body’s response to infection and penetration of antibiotics.

Conclusions

Our pilot study presents new diagnostic possibilities of microscopic imaging with the atomic force microscope (AFM) and scanning electron microscope (SEM) to identify pathogens on routinely used disposable medical devices, such as the central venous catheter. On the other hand, this range of diagnostics reveals the potential to constantly improve medical materials which come into direct contact with patients’ tissues. It is important to create a database of microscopic images, which would be a repeatable diagnostic pattern and fully correlated with the results of microbiological analysis, because it would facilitate initial quick diagnosis of a potential CRBSI.

Catheter salvage strategies in children with central venous catheter related or associated bloodstream infections: a systematic review and meta-analysis

BACKGROUND

Optimal management of Central Venous Catheter related, or associated, bloodstream infections (CRBSI or CLABSI) in children is not established.

OBJECTIVE

To evaluate successful of catheter salvage strategies in pediatric patients.

METHODS

Studies retrieved from medical databases and article reference lists. Data were collected relating to clinical outcomes of 2 treatments: systemic antibiotics alone or in association with antimicrobial lock therapy (ALT). 95% CIs and OR were calculated from a mixed logistic effects model. Heterogeneity was summarized using I2 statistics. Publication bias was investigated by Egger's regression test and funnel plots.

RESULTS

From 345 identified publications, 19 met inclusion criteria (total of 914 attempted salvage strategies. To achieve successful catheter salvage, in CRBSI the addition of ALT was superior to systemic antibiotics alone (OR -0.40, 95%CI -1.41 - 0.62): 77% (95%CI 69-85, I2=42.5%, p=0.12) and 68% of success (95%CI 59-77, I2=0, p<0.05), respectively. CRBSI recurrence was less common in studies that used ALT compared with systemic antibiotics alone: 5% (95%CI 0-13, I2=59.7%; p=0.03) and 18% of recurrence (95%CI, 9-28, I2=0, p< 0.05), respectively. Recurrences were low with both antibiotic-locks and ethanol-lock. No clear benefits of ALT addition compared to systemic antibiotic only was found in CLABSI (OR -0.81, 95% CI -0.80 - 2.43).

CONCLUSIONS

The addition of an antimicrobial lock solution to systemic antibiotic may be beneficial for successful catheter salvage in pediatric patients with CRBSI, depending on etiology, whilst no statistically significant difference between systemic antibiotic with or without addition of an antimicrobial lock solution was found regarding CLABSI.

Management of enterococcal central line-associated bloodstream infections in patients with cancer

OBJECTIVE

Enterococcus species are the third most common organisms causing central line-associated bloodstream infections (CLABSIs). The management of enterococcal CLABSI, including the need for and timing of catheter removal, is not well defined. We therefore conducted this study to determine the optimal management of enterococcal CLABSI in cancer patients.

METHODS

We reviewed data for 542 patients diagnosed with Enterococcus bacteremia between September 2011 to December 2018. After excluding patients without an indwelling central venous catheter (CVC), polymicrobial bacteremia or with CVC placement less than 48 h from bacteremia onset we classified the remaining 397 patients into 3 groups: Group 1 (G1) consisted of patients with CLABSI with mucosal barrier injury (MBI), Group 2 (G2) included patients with either catheter-related bloodstream infection (CRBSI) as defined in 2009 Clinical Practice Guidelines for the Diagnosis and Management of Intravascular Catheter-Related Infection by the Infectious Diseases Society of America (IDSA) or CLABSI without MBI, and Group 3 (G3) consisted of patients who did not meet the CDC criteria for CLABSI. The impact of early (< 3 days after bacteremia onset) and late (3-7 days) CVC removal was compared. The composite primary outcome included absence of microbiologic recurrence, 90-day infection-related mortality, and 90-day infection-related complications.

RESULTS

Among patients in G2, CVC removal within 3 days of bacteremia onset was associated with a trend towards a better overall outcome than those whose CVCs were removed later between days 3 to 7 (success rate 88% vs 63%). However, those who had CVCs retained beyond 7 days had a similar successful outcome than those who had CVC removal < 3 days (92% vs. 88%). In G1, catheter retention (removal > 7 days) was associated with a better success rates than catheter removal between 3 and 7 days (93% vs. 67%, p = 0.003). In non-CLABSI cases (G3), CVC retention (withdrawal > 7 days) was significantly associated with a higher success rates compared to early CVC removal (< 3 days) (90% vs. 64%, p = 0.006).

CONCLUSION

Catheter management in patients with enterococcal bacteremia is challenging. When CVC removal is clinically indicated in patients with enterococcal CLABSI, earlier removal in less than 3 days may be associated with better outcomes. Based on our data, we cannot make firm conclusions about whether earlier removal (< 3 days) could be associated with better outcomes in patients with Enterococcal CLABSI whose CVC withdrawal is clinically indicated. In contrast, it seemed that catheter retention was associated to higher success outcome rates. Therefore, future studies are needed to clearly assess this aspect.

Risk of catheter-related bloodstream infection associated with midline catheters compared with peripherally inserted central catheters: A meta-analysis

Background

Both midline catheters (MCs) and peripherally inserted central catheters (PICCs) can cause catheter‐related bloodstream infection (CRBSI), but the prevalence associated with each is not clear.

Objective

To compare the risk of CRBSI between MCs and PICCs with a meta‐analysis.

Methods

The Web of Science Core Collection, PubMed, Scopus, Embase, The Cochrane Library and ProQuest were searched. All studies comparing the risk of CRBSI between MCs and PICCs were included. Selected studies were assessed for methodological quality using the Downs and Black checklist. Two authors independently assessed the literature and extracted the data. A fixed effects model was used to generate estimates of CRBSI risk in patients with MCs versus PICCs. Publication bias was evaluated, and meta‐analyses were conducted with RevMan 5.3.

Results

A total of 167 studies were identified. Ten studies were collected, involving 33,322 patients. The prevalence of CRBSI with MCs and PICCs was 0.58% (40/6,900) and 0.48% (127/26,422), respectively. Meta‐analysis showed that the prevalence of CRBSI was not significantly different between MCs and PICCs (RR = 0.77, 95% CI: 0.50–1.17, p = .22). While the result showed that the prevalence of CRBSI with MCs was lower than that with PICCs (RR = 0.55, 95% CI: 0.33–0.92, p = .02) after poor‐quality studies were removed. The sensitivity analysis shows that the results from this meta‐analysis are fair in overall studies and non‐poor‐quality studies. All studies have no significant publication bias.

Conclusions

This study provides the first systematic assessment of the risk of CRBSI between MCs and PICCs and provides evidence for the selection of appropriate vascular access devices for intravenous infusion therapy in nursing. The prevalence of CRBSI was not significantly different between them.

Predictive factors for Enterococcus faecalis in complicated community-acquired urinary tract infections in older patients

AIM

Risk factors for complicated community acquired Enterococcus faecalis urinary tract infection (UTI) in older patients are not well known.

METHODS

We identified the predictive factors for E. faecalis on a cohort of 659 older patients admitted to hospital with complicated UTI. We also examined the adequacy of empirical antimicrobial therapy and outcomes in E. faecalis UTI. Multivariable logistic regression was used to identify predictors of E. faecalis UTI.

RESULTS

A total of 87 (13.2%) patients had E. faecalis UTI; of these 63.2% were men, their mean age was 82.3 years and they had a great number of comorbidities. Severe sepsis or septic shock was present in 50.5%, and bacteremia was present in 26%. Indwelling urinary catheter and previous urinary instrumentation were risk factors for E. faecalis UTI by multivariate analysis (OR 2.05; 95% CI 1.15-3.65 and OR 2.16; 95% CI 1.08-4.34, respectively). Inadequate empirical antimicrobial therapy was higher in E. faecalis UTI than in UTI caused by Gram-negative microorganisms (66.6% vs 19%, P < 0.001). No significant differences in length of hospital stay or mortality were noted between E. faecalis and Gram-negative UTI.

CONCLUSIONS

In older patients admitted to hospital with complicated community-acquired UTI, E. faecalis should be considered for empirical treatment if the patient has a urinary catheter or previous urinary tract instrumentation in order to avoid inadequate empirical antibiotic therapy. Geriatr Gerontol Int 2019; ••: ••-••.

Diagnosis and treatment of catheter-related bloodstream infection: Clinical guidelines of the Spanish Society of Infectious Diseases and Clinical Microbiology and (SEIMC) and the Spanish Society of Spanish Society of Intensive and Critical Care Medicine and Coronary Units (SEMICYUC)

Catheter-related bloodstream infections (CRBSI) constitute an important cause of hospital-acquired infection associated with morbidity, mortality, and cost. The aim of these guidelines is to provide updated recommendations for the diagnosis and management of CRBSI in adults. Prevention of CRBSI is excluded. Experts in the field were designated by the two participating Societies (the Spanish Society of Infectious Diseases and Clinical Microbiology and [SEIMC] and the Spanish Society of Spanish Society of Intensive and Critical Care Medicine and Coronary Units [SEMICYUC]). Short-term peripheral venous catheters, non-tunneled and long-term central venous catheters, tunneled catheters and hemodialysis catheters are covered by these guidelines. The panel identified 39 key topics that were formulated in accordance with the PICO format. The strength of the recommendations and quality of the evidence were graded in accordance with ESCMID guidelines. Recommendations are made for the diagnosis of CRBSI with and without catheter removal and of tunnel infection. The document establishes the clinical situations in which a conservative diagnosis of CRBSI (diagnosis without catheter removal) is feasible. Recommendations are also made regarding empirical therapy, pathogen-specific treatment (coagulase-negative staphylococci, Staphylococcus aureus, Enterococcus spp., Gram-negative bacilli, and Candida spp.), antibiotic lock therapy, diagnosis and management of suppurative thrombophlebitis and local complications.

Catheter-related infections: does the spectrum of microbial causes change over time? A nationwide surveillance study

OBJECTIVES

To estimate the incidence and epidemiology of catheter-related bloodstream infections (CRBSIs) on a national scale by using prospective epidemiological data from the Swiss Antibiotic Resistance Surveillance System (ANRESIS).

DESIGN

Observational study.

SETTING

National surveillance from 2008 to 2015 of acute hospitals in Switzerland.

PARTICIPANTS

We included acute Swiss hospitals that sent blood cultures and catheter tip culture results on a regular basis during the entire study period to the ANRESIS database.

OUTCOME MEASURE

A catheter-related bloodstream infection (termed 'modified CRBSI', mCRBSI) was defined as isolating the same microorganism with identical antibiogram from ≥1 blood cultures (performed ±7 days around the catheter removal) as the one recovered from the catheter tip. Incidence rates of mCRBSI were calculated per 1000 admissions.

RESULTS

From 2008 to 2015, the mCRBSI incidence rate decreased from 0.83 to 0.58 episodes/1000 admissions (-6% per year, p<0.001). Coagulase-negative staphylococci, Staphylococcus aureus and fungi all exhibited decreasing trends, while rates of enterococci and Gram-negative bacteria remained stable.

CONCLUSIONS

The overall incidence of mCRBSI in Switzerland is decreasing; however, the incidence of mCRBSI due to Enterococci and Gram-negative micro-organisms did not change over time. These pathogens may grow in importance in catheter-related infections, which would have clinical implications for the choice of empirical treatment.

Bloodstream infections caused by Enterococcus spp: A 10-year retrospective analysis at a tertiary hospital in China

In order to discover the risk factors for 30-day mortality in bloodstream infections (BSI) caused by Enterococcus spp. strains, we explored the clinical and therapeutic profile of patients with Enterococcus spp. BSI and the characteristics of this condition. A total of 64 patients with BSI caused by Enterococcus spp. who were treated in our hospital between 2006 and 2015 were included in the study. The clinical features of patients, microbiology, and 30-day mortality were collected from the electronic medical records database and analyzed. The results showed that there were 38 patients infected by Enterococcus faecalis (E. faecalis), 24 by Enterococcus faecium (E. faecium), 1 by Enterococcus casseliflavus (E. casseliflavus), and 1 by Enterococcus gallinarum (E. gallinarum). A Charlson comorbidity score ≥5, corticosteroid treatment, placement of catheters or other prosthetic devices and history of antibiotic use were found more frequently in E. faecium BSI patients than in E. faecalis patients (P=0.017, P=0.027, P=0.008 and P=0.027, respectively). Furthermore, the univariate and multivariate analysis showed that corticosteroid treatment (OR=17.385, P=0.008), hospital acquisition (OR=16.328, P=0.038), and vascular catheter infection (OR=14.788, P=0.025) were all independently associated with 30-day mortality. Our results indicate that E. faecalis and E. faecium are two different pathogens with unique microbiologic characteristics, which cause different clinical features in BSI, and the empiric antimicrobial treatments are paramount for patients with enterococcal BSI.

Magnitude of enterococcal bacteremia in trauma patients admitted for intensive trauma care: a tertiary care experience from South asian country

Background:

Bloodstream infection (BSI) and bacteremias due to Enterococcus spp. are increasing worldwide with the current need to understand its causes among hospitalized trauma patients. Hence, the study was conducted.

Methodology:

A 3-year retrospective laboratory cum clinical based study was performed at a level I trauma center in India. Patients with health care associated enterococcal bacteremia were identified using the hospital database, their episodes of BSI/bacteremia calculated and their clinical records and treatment were noted.

Results:

A total of 104 nonrepetitive Enterococcus spp. was isolated of which Enterococcus faecium was the most common (52%). High-level resistance to gentamicin high-level aminoglycoside resistance was seen in all the Enterococcus spp. causing bacteremia, whereas a low resistance to vancomycin and teichoplanin was observed. Overall mortality was more in patients infected with vancomycin-resistant Enterococcus (5/11, 46%) compared to those with vancomycin sensitive Enterococcus (9/93, 10%); though no significant association of mortality with Enterococcus spp. bacteremia (P > 0.05) was seen. The rate of bacteremia due to Enterococcus spp. was 25.4 episodes/1,000 admissions (104/4,094) during the study period.

Conclusion:

Enterococcal bacteremia is much prevalent in trauma care facilities. Here, a microbiologist can act as a sentinel and help in preventing such infections.

The NOVA score: a proposal to reduce the need for transesophageal echocardiography in patients with enterococcal bacteremia

BACKGROUND

Frequency of enterococcal bloodstream infection (E-BSI) is increasing, and the number of episodes complicated by infective endocarditis (IE) varies. Performing transesophageal echocardiography (TEE) in all patients with E-BSI is costly and time-consuming. Our objectives were to identify patients with E-BSI who are at very low risk of enterococcal IE (and therefore do not require TEE) and to compare the outcome of E-BSI in patients with/without IE.

METHODS

Between September 2003 and October 2012, we performed a prospective cohort study (all patients with E-BSI) and a case-control study (patients with/without enterococcal IE) in our center.

RESULTS

We detected 1515 patients with E-BSI and 65 with enterococcal IE (4.29% of all episodes of E-BSI, 16.7% of patients with E-BSI who underwent transthoracic echocardiography, and 35.5% of all patients with E-BSI who underwent TEE). We developed a bedside predictive score for enterococcal IE-Number of positive blood cultures, Origin of the bacteremia, previous Valve disease, Auscultation of heart murmur (NOVA) score-based on the following variables: Number of positive blood cultures (3/3 blood cultures or the majority if more than 3), 5 points; unknown Origin of bacteremia, 4 points; prior heart Valve disease, 2 points; Auscultation of a heart murmur, 1 point (receiver operating characteristic = 0.83). The best cutoff corresponded to a score ≥4 (sensitivity, 100%; specificity, 29%). A score <4 points suggested a very low risk for enterococcal IE and that TEE could be obviated.

CONCLUSIONS

Enterococcal IE may be more frequent than generally thought. Depending on local prevalence of endocarditis, application of the NOVA score may safely obviate echocardiography in 14%-27% of patients with E-BSI.

Uncommon aetiological agents of catheter-related bloodstream infections

The clinical and microbiological characteristics of catheter-related bloodstream infection (CR-BSI) due to uncommon microorganisms was assessed in a retrospective case-control study over a 9-year period in a tertiary teaching hospital. Uncommon microorganisms were defined as those representing <0·5% of all CR-BSI. Diagnosis of CR-BSI required that the same microorganism was grown from at least one peripheral venous blood culture and a catheter tip culture. Thirty-one episodes of CR-BSI were identified due to 13 different genera and these accounted for 2·3% of all CR-BSI in the hospital. Although these infections were not associated with increased mortality, they occurred in patients with more severe underlying conditions who were receiving prolonged antibiotic therapy.

Catheter removal versus retention in the management of catheter-associated enterococcal bloodstream infections

BACKGROUND

Enterococci are an important cause of central venous catheter (CVC)-associated bloodstream infections (CA-BSI). It is unclear whether CVC removal is necessary to successfully manage enterococcal CA-BSI.

METHODS

A 12-month retrospective cohort study of adults with enterococcal CA-BSI was conducted at a tertiary care hospital; clinical, microbiological and outcome data were collected.

RESULTS

A total of 111 patients had an enterococcal CA-BSI. The median age was 58.2 years (range 21 to 94 years). There were 45 (40.5%) infections caused by Entercoccus faecalis (among which 10 [22%] were vancomycin resistant), 61 (55%) by Enterococcus faecium (57 [93%] vancomycin resistant) and five (4.5%) by other Enterococcus species. Patients were treated with linezolid (n=51 [46%]), vancomycin (n=37 [33%]), daptomycin (n=11 [10%]), ampicillin (n=2 [2%]) or quinupristin/dalfopristin (n=2 [2%]); seven (n=6%) patients did not receive adequate enterococcal treatment. Additionally, 24 (22%) patients received adjunctive gentamicin treatment. The CVC was retained in 29 (26.1%) patients. Patients with removed CVCs showed lower rates of in-hospital mortality (15 [18.3%] versus 11 [37.9]; P=0.03), but similar rates of recurrent bacteremia (nine [11.0%] versus two (7.0%); P=0.7) and a similar post-BSI length of hospital stay (median days [range]) (11.1 [1.7 to 63.1 days] versus 9.3 [1.9 to 31.8 days]; P=0.3). Catheter retention was an independent predictor of mortality (OR 3.34 [95% CI 1.21 to 9.26]).

CONCLUSIONS

To the authors' knowledge, the present article describes the largest enterococcal CA-BSI series to date. Mortality was increased among patients who had their catheter retained. Additional prospective studies are necessary to determine the optimal management of enterococcal CA-BSI.