Predicting Risk of Endocarditis Using a Clinical Tool (PREDICT): Scoring System to Guide Use of Echocardiography in the Management of Staphylococcus aureus Bacteremia.
ABSTRACT: Infective endocarditis (IE) is a serious complication of Staphylococcus aureus bacteremia (SAB). There is limited clinical evidence to guide use of echocardiography in the management of SAB cases.Baseline and 12-week follow-up data of all adults hospitalized at our institution with SAB from 2006 to 2011 were reviewed. Clinical predictors of IE were identified using multivariable logistic regression analysis.Of the 757 patients screened, 678 individuals with SAB (24% community acquired, 56% healthcare associated, and 20% nosocomial) met study criteria. Eighty-five patients (13%) were diagnosed with definite IE within the 12 weeks of initial presentation based on modified Duke criteria. The proportion of patients with IE was 22% (36/166) in community-acquired SAB, 11% (40/378) in community-onset healthcare-associated SAB, and 7% (9/136) in nosocomial SAB. Community-acquired SAB, presence of cardiac device, and prolonged bacteremia (? 72 hours) were identified as independent predictors of IE in multivariable analysis. Two scoring systems, day 1 (SAB diagnosis day) and day 5 (when day 3 culture results are known), were derived based on the presence of these risk factors, weighted in magnitude by the corresponding regression coefficients. A score of ? 4 for day 1 model had a specificity of 96% and sensitivity of 21%, whereas a score of <2 for day 5 model had a sensitivity of 98.8% and negative predictive value of 98.5%.We propose 2 novel scoring systems to guide use of echocardiography in SAB cases. Larger prospective studies are needed to validate the classification performance of these scoring systems.
Project description:To update the epidemiology of S. aureus bloodstream infection (SAB) in a high-income country and its link with infective endocarditis (IE).All consecutive adult patients with incident SAB (n = 2008) were prospectively enrolled between 2009 and 2011 in 8 university hospitals in France.SAB was nosocomial in 54%, non-nosocomial healthcare related in 18% and community-acquired in 26%. Methicillin resistance was present in 19% of isolates. SAB Incidence of nosocomial SAB was 0.159/1000 patients-days of hospitalization (95% confidence interval [CI] 0.111-0.219). A deep focus of infection was detected in 37%, the two most frequent were IE (11%) and pneumonia (8%). The higher rates of IE were observed in injecting drug users (IE: 38%) and patients with prosthetic (IE: 33%) or native valve disease (IE: 20%) but 40% of IE occurred in patients without heart disease nor injecting drug use. IE was more frequent in case of community-acquired (IE: 21%, adjusted odds-ratio (aOR) = 2.9, CI = 2.0-4.3) or non-nosocomial healthcare-related SAB (IE: 12%, aOR = 2.3, CI = 1.4-3.5). S. aureus meningitis (IE: 59%), persistent bacteremia at 48 hours (IE: 25%) and C-reactive protein > 190 mg/L (IE: 15%) were also independently associated with IE. Criteria for severe sepsis or septic shock were met in 30% of SAB without IE (overall in hospital mortality rate 24%) and in 51% of IE (overall in hospital mortality rate 35%).SAB is still a severe disease, mostly related to healthcare in a high-income country. IE is the most frequent complication and occurs frequently in patients without known predisposing conditions.
Project description:Staphylococcus aureus is an important cause of community-associated bacteremia (SAB) and infective endocarditis (IE). No significant differences in distribution or frequency of genes encoding virulence factors, including genes encoding adhesins, were found between isolates from the IE and SAB groups (12 IE and 10 SAB patients).
Project description:Echocardiography is fundamental for diagnosing infective endocarditis (IE) in patients with Staphylococcus aureus bacteremia (SAB), but whether all such patients require transesophageal echocardiography (TEE) is controversial.We identified SAB cases between February 2008 and April 2012. We compared sensitivity and specificity of transthoracic echocardiography (TTE) and TEE for evidence of IE, and we determined impacts of IE risk factors and TTE image quality on comparative sensitivities of TTE and TEE and their impact on clinical decision making.Of 215 evaluable SAB cases, 193 (90%) had TTE and 130 (60%) had TEE. In 119 cases with both tests, IE was diagnosed in 29 (24%), for whom endocardial involvement was evident in 25 (86%) by TEE, vs only 6 (21%) by TTE (P < .001). Transesophageal echocardiography was more sensitive than TTE regardless of risk factors. Even among the 66 cases with adequate or better quality TTE images, sensitivity was only 4 of 17 (24%) for TTE, vs 16 of 17 (94%) for TEE (P < .001). Among 130 patients with TEE, the TEE results, alone or with TTE results, influenced treatment duration in 56 (43%) cases and led to valve surgery in at least 4 (6%). It is notable that, despite vigorous efforts to obtain both tests routinely, TEE was not done in 86 cases (40%) for various reasons, including pathophysiological contraindications (14%), patient refusal or other patient-related factors (16%), and provider declination or system issues (10%).Patients with SAB should undergo TEE when possible to detect evidence for IE, especially if the results might affect management.
Project description:Background:Many genera and species of Streptococcus-like bacteria (SLB) can cause infective endocarditis (IE), but little is known about the epidemiology of and the risk factors for IE in SLB-bacteremia. The aim of the study was to analyze this in a cohort of patients with SLB-bacteremia, focusing on Abiotrophia, Aerococcus, Gemella, and Granulicatella. We also evaluated whether published scoring systems generated for other Gram-positive bacteria known to cause IE (HANDOC for streptococci and NOVA and DENOVA for enterococci) could be used in SLB bacteremia to decide whether transesophageal echocardiography (TEE) could be omitted. Methods:Positive blood cultures with SLB were retrieved from population-based registries in Sweden (3.2 million inhabitants), from January 2012 to December 2017. Clinical data were collected from medical records. Risk factors for IE were analyzed and the performances of the scoring systems were calculated. Results:The incidence of bacteremia with the 4 SLB genera was 30 episodes/1 000 000 population per year, of which Aerococcus contributed with 18. Among 568 episodes of bacteremia, 32 cases of IE were identified (5.6%). Infective endocarditis was most common in bacteremia with Abiotrophia (4 of 19) followed by Granulicatella (9 of 124), Gemella (6 of 87), and Aerococcus (13 of 338). NOVA had 100% sensitivity to identify IE but a low specificity (15%). For HANDOC and DENOVA, the sensitivities were 97% and 91%, respectively, whereas specificities were 85% and 90%, respectively, and numbers needed to screen were 3.6 and 2.8, respectively. Conclusions:Bacteremia with these SLB is relatively rare, and the decision whether TEE should be performed or not could be based on either HANDOC or DENOVA.
Project description:Background:The risk of endocarditis among patients with Staphylococcus aureus bacteremia is not uniform, and a number of different scores have been developed to identify patients whose risk is less than 5%. The optimal echocardiography strategy for these patients is uncertain. Methods:We used decision analysis and Monte Carlo simulation using input parameters taken from the existing literature. The model examined patients with S aureus bacteremia whose risk of endocarditis is less than 5%, generally those with nosocomial or healthcare-acquired bacteremia, no intracardiac prosthetic devices, and a brief duration of bacteremia. We examined 6 echocardiography strategies, including the use of transesophageal echocardiography, transthoracic echocardiography, both modalities, and neither. The outcome of the model was 90-day survival. Results:The optimal echocardiography strategy varied with the risk of endocarditis and the procedural mortality associated with transesophageal echocardiography. No echocardiography strategy offered an absolute benefit in 90-day survival of more than 0.5% compared with the strategy of not performing echocardiography and treating with short-course therapy. Strategies using transesophageal echocardiography were never preferred if the mortality of this procedure was greater than 0.5%. Conclusions:In patients identified to be at low risk of endocarditis, the choice of echocardiography strategy appears to exert a very small influence on 90-day survival. This finding may render test-treatment trials unfeasible and should prompt clinicians to focus on other, more important, management considerations in these patients.
Project description:The complement system is a vital component of the innate immune system, though its role in bacteremia is poorly understood. We present complement levels in Staphylococcus aureus bacteremia (SAB) and Gram-negative bacteremia (GNB) and describe observed associations of complement levels with clinical outcomes. Complement and cytokine levels were measured in serum samples from 20 hospitalized patients with SAB, 20 hospitalized patients with GNB, 10 non-infected hospitalized patients, and 10 community controls. C5a levels were significantly higher in patients with SAB as compared to patients with GNB. Low C4 and C3 levels were associated with septic shock and 30-day mortality in patients with GNB, and elevated C3 was associated with a desirable outcome defined as absence of (1) septic shock, (2) acute renal failure, and (3) death within 30 days of bacteremia. Low levels of C9 were associated with septic shock in patients with GNB but not SAB. Elevated IL-10 was associated with increased 30-day mortality in patients with SAB. Complement profiles differ in patients with SAB and those with GNB. Measurement of IL-10 in patients with SAB and of C4, C3, and C9 in patients with GNB may help to identify those at higher risk for poor outcomes.
Project description:Background:Antimicrobial stewardship programs (ASPs) improve Staphylococcus aureus bacteremia (SAB) management. The objective of the current study was to evaluate the effect of unsolicited prospective audit and feedback (PAF) using a standardized SAB bundle form on the management of SAB. Methods:Multicenter, pre-post quasi-experimental study of inpatients with SAB. The ASP developed an evidence-based SAB management bundle that included recommendations for infectious diseases consultation, blood culture clearance, appropriate empiric and definitive therapy, echocardiography, adequate treatment duration, and source control where applicable. ASP pharmacists performed PAF using a standardized form outlining bundle components. The primary outcome was bundle component adherence. Secondary outcomes were length of stay, 30-day readmission rate, and in-hospital and 30-day mortality rates. Results:A total of 199 patients were included (preintervention group, 62; intervention group, 137). Bundle implementation with PAF resulted in significant improvements in infectious diseases consultation (56.5% in preintervention vs 93.4% in intervention group), appropriate definitive antibiotic therapy (83.9% vs 99.3%), ordering echocardiography (72.6% vs 95.6%), and adequate treatment duration (87.0% vs 100%) (all P < .001). Overall bundle adherence increased by 43.8% (P < .001). Readmission and 30-day mortality rates decreased, but this difference did not reach statistical significance. Conclusions:Unsolicited PAF using a standardized SAB management bundle significantly improved adherence to evidence-based recommendations. This simple yet effective ASP-driven intervention can ensure consistent management of a highly morbid infection.
Project description:BACKGROUND:Cirrhosis always goes with profound immunity compromise, and makes those patients easily be the target of pneumonia. Cirrhotic patients with pneumonia have a dramatically increased mortality. To recognize the risk factors of mortality and to optimize stratification are critical for improving survival rate. METHODS:Two hundred and three cirrhotic patients with pneumonia at a tertiary care hospital were included in this retrospective study. Demographical, clinical and laboratory parameters, severity models and prognosis were recorded. Multivariate Cox regression analysis was used to identify independent predictors of 30-day and 90-day mortality. Area under receiver operating characteristics curves (AUROC) was used to compare the predictive value of different prognostic scoring systems. RESULTS:Patients with nosocomial acquired or community acquired pneumonia indicated similar prognosis after 30- and 90-day follow-up. However, patients triggered acute-on-chronic liver failure (ACLF) highly increased mortality (46.4% vs 4.5% for 30-day, 69.6% vs 11.2% for 90-day). Age, inappropriate empirical antibiotic therapy (HR: 2.326 p?=?0.018 for 30-day and HR: 3.126 p?<?0.001 for 90-day), bacteremia (HR: 3.037 p?=?0.002 for 30-day and HR: 2.651 p?=?0.001 for 90-day), white blood cell count (WBC) (HR: 1.452 p?<?0.001 for 30-day and HR: 1.551 p?<?0.001 for 90-day) and total bilirubin (HR: 1.059 p?=?0.002 for 90-day) were independent factors for mortality in current study. Chronic liver failure-sequential organ failure assessment (CLIF-SOFA) displayed highest AUROC (0.89 and 0.90, 95% CI: 0.83-0.95 and 0.85-0.95 for 30-day and 90-day respectively) in current study. CONCLUSIONS:This study found age, bacteremia, WBC, total bilirubin and inappropriate empirical antibiotic therapy were independently associated with increased mortality. Pneumonia triggered ACLF remarkably increased mortality. CLIF-SOFA was more accurate in predicting mortality than other five prognostic models (model for end-stage liver disease (MELD), MELD-Na, quick sequential organ failure assessment (qSOFA), pneumonia severity index (PSI), Child-Turcotte-Pugh (CTP) score).
Project description:Several studies have shown that patients with bacteremia caused by methicillin-resistant Staphylococcus aureus (MRSA) have worse outcomes than those with bacteremia caused by methicillin-susceptible S. aureus (MSSA). However, only a limited number of studies have stratified the MRSA isolates into healthcare-associated (HA-) and community-associated (CA-) MRSA strains in such a comparison. This three-year retrospective cohort study, enrolling adult patients with nosocomial S. aureus bacteremia (SAB), was designed to investigate whether CA-MRSA and/or HA-MRSA strains were associated with different outcomes in comparison to MSSA in such a setting. The drug susceptibilities and staphylococcal cassette chromosome mec (SCCmec) types were determined for all of the causative isolates available. The MRSA bacteremia was further categorized into those caused by CA-MRSA strains (CA-MRSA-S bacteremia) when the causative isolates carried the type IV or V SCCmec element, those caused by HA-MRSA strains (HA-MRSA-S bacteremia) when the isolates carried the type I, II, or III SCCmec element, or unclassified MRSA bacteremia when the isolates were not available. The relevant demographic, clinical, and laboratory data were collected by reviewing the patients' charts. The primary outcome was all-cause in-hospital mortality. A total of 353 patients were studied. The overall in-hospital mortality rate was 32.6%, with 23.3% in MSSA, 30.5% in CA-MRSA-S, 47.5% in HA-MRSA-S, and 35.3% in unclassified MRSA bacteremia, respectively. The multivariate analysis showed that HA-MRSA-S, but not CA-MRSA-S, bacteremia was associated with a significantly worse outcome compared with MSSA. The other risk factors independently associated with all-cause in-hospital mortality included the Charlson co-morbidity index, septic shock, thrombocytopenia, and persistent bacteremia. Resistance to linezolid and daptomycin was found among the MRSA isolates. The present study showed that bacteremia caused by HA-MRSA-S, but not CA-MRSA-S, was an independent risk factor for all-cause in-hospital mortality in patients with nosocomial SAB. Continuous monitoring regarding the susceptibilities of MRSA to linezolid and daptomycin is necessary.
Project description:Cell wall peptidoglycan stimulates interleukin 10 (IL-10) production in Staphylococcus aureus bacteremia (SaB) animal models, but clinical data are not available. This study evaluates the impact of intravascular bacterial cell numbers (ie, the level of bacteremia), in patients at the time of clinical presentation on IL-10 production and its association with S. aureus bacteremia (SaB) mortality.Blood and isolates were collected in 133 consecutive SaB patients. Serum IL-10 was quantified by an electrochemoluminescence assay. Bacterial inoculum was measured in patient sera with elevated (n = 8) or low (n = 8) IL-10 using a magnetic bacterial capture assay. Staphylococcus aureus from these 2 groups were introduced into whole blood ex vivo to determine IL-10 production with variable inocula.IL-10 serum concentration was higher in SaB patient mortality (n = 27) vs survival (n = 106) (median, 36.0 pg/mL vs 10.4 pg/mL, respectively, P < .001). Patients with elevated IL-10 more often had endovascular SaB sources. The inoculum level of SaB was higher in patients with elevated serum IL-10 vs patients with low IL-10 (35.5 vs 0.5 median CFU/mL; P = .044). Ex vivo studies showed that 108 CFU/mL yielded greater IL-10 than did 103 CFU/mL (4.4 ± 1.8 vs 1.0 ± 0.6 pg/mL; P < .01).Elevated IL-10 serum concentrations at clinical presentation of SaB were highly associated with mortality. High intravascular peptidoglycan concentration, driven by a higher level of bacteremia, is a key mediator of IL-10 anti-inflammatory response that portends poor clinical outcome. Using IL-10 as an initial biomarker, clinicians may consider more aggressive antimicrobials for rapid bacterial load reduction in high-risk SaB patients.