New diagnostic criteria for infective endocarditis. A study of sensitivity and specificity

Evaluation of the 2023 Duke-International Society of Cardiovascular Infectious Diseases Criteria in a Multicenter Cohort of Patients With Suspected Infective Endocarditis

BACKGROUND

Since publication of Duke criteria for infective endocarditis (IE) diagnosis, several modifications have been proposed. We aimed to evaluate the diagnostic performance of the Duke-ISCVID (International Society of Cardiovascular Infectious Diseases) 2023 criteria compared to prior versions from 2000 (Duke-Li 2000) and 2015 (Duke-ESC [European Society for Cardiology] 2015).

METHODS

This study was conducted at 2 university hospitals between 2014 and 2022 among patients with suspected IE. A case was classified as IE (final IE diagnosis) by the Endocarditis Team. Sensitivity for each version of the Duke criteria was calculated among patients with confirmed IE based on pathological, surgical, and microbiological data. Specificity for each version of the Duke criteria was calculated among patients with suspected IE for whom IE diagnosis was ruled out.

RESULTS

In total, 2132 episodes with suspected IE were included, of which 1101 (52%) had final IE diagnosis. Definite IE by pathologic criteria was found in 285 (13%), 285 (13%), and 345 (16%) patients using the Duke-Li 2000, Duke-ESC 2015, or the Duke-ISCVID 2023 criteria, respectively. IE was excluded by histopathology in 25 (1%) patients. The Duke-ISCVID 2023 clinical criteria showed a higher sensitivity (84%) compared to previous versions (70%). However, specificity of the new clinical criteria was lower (60%) compared to previous versions (74%).

CONCLUSIONS

The Duke-ISCVID 2023 criteria led to an increase in sensitivity compared to previous versions. Further studies are needed to evaluate items that could increase sensitivity by reducing the number of IE patients misclassified as possible, but without having detrimental effect on specificity of Duke criteria.

External Validation of the 2023 Duke-International Society for Cardiovascular Infectious Diseases Diagnostic Criteria for Infective Endocarditis

BACKGROUND

The 2023 Duke-International Society of Cardiovascular Infectious Diseases (ISCVID) criteria for infective endocarditis (IE) were introduced to improve classification of IE for research and clinical purposes. External validation studies are required.

METHODS

We studied consecutive patients with suspected IE referred to the IE team of Amsterdam University Medical Center (from October 2016 to March 2021). An international expert panel independently reviewed case summaries and assigned a final diagnosis of "IE" or "not IE," which served as the reference standard, to which the "definite" Duke-ISCVID classifications were compared. We also evaluated accuracy when excluding cardiac surgical and pathologic data ("clinical" criteria). Finally, we compared the 2023 Duke-ISCVID with the 2000 modified Duke criteria and the 2015 and 2023 European Society of Cardiology (ESC) criteria.

RESULTS

A total of 595 consecutive patients with suspected IE were included: 399 (67%) were adjudicated as having IE; 111 (19%) had prosthetic valve IE, and 48 (8%) had a cardiac implantable electronic device IE. The 2023 Duke-ISCVID criteria were more sensitive than either the modified Duke or 2015 ESC criteria (84.2% vs 74.9% and 80%, respectively; P < .001) without significant loss of specificity. The 2023 Duke-ISCVID criteria were similarly sensitive but more specific than the 2023 ESC criteria (94% vs 82%; P < .001). The same pattern was seen for the clinical criteria (excluding surgical/pathologic results). New modifications in the 2023 Duke-ISCVID criteria related to "major microbiological" and "imaging" criteria had the most impact.

CONCLUSIONS

The 2023 Duke-ISCVID criteria represent a significant advance in the diagnostic classification of patients with suspected IE.

Candida endocarditis: Update on management considerations

The rise in incidence rates of invasive candidiasis warrants an increase in attention and efforts toward preventing and treating this virulent infection. Cardiac involvement is one of the most feared sequelae and has a poor prognosis. Despite the introduction of several novel antifungal agents over the past quarter century, complications and mortality rates due to Candida endocarditis have remained high. Although fungal endocarditis has a mechanism similar to bacterial endocarditis, no specific diagnostic criteria or algorithm exists to help guide its management. Furthermore, recent data has questioned the current guidelines recommending a combined approach of antifungal agents with surgical valve or indwelling prostheses removal. With the emergence of multidrug-resistant Candida auris, a focus on improved prophylactic measures and management strategies is necessary.

18F-FDG-Based Radiomics and Machine Learning: Useful Help for Aortic Prosthetic Valve Infective Endocarditis Diagnosis?

BACKGROUND

Fluorine-18 fluorodeoxyglucose (¹⁸F-FDG)-positron emission tomography (PET)/computed tomography (CT) results in better sensitivity for prosthetic valve endocarditis (PVE) diagnosis, but visual image analysis results in relatively weak specificity and significant interobserver variability.

OBJECTIVES

The primary objective of this study was to evaluate the performance of a radiomics and machine learning-based analysis of ¹⁸F-FDG PET/CT (PET-ML) as a major criterion for the European Society of Cardiology score using machine learning as a major imaging criterion (ESC-ML) in PVE diagnosis. The secondary objective was to assess performance of PET-ML as a standalone examination.

METHODS

All ¹⁸F-FDG-PET/CT scans performed for suspected aortic PVE at a single center from 2015 to 2021 were retrospectively included. The gold standard was expert consensus after at least 3 months' follow-up. The machine learning (ML) method consisted of manually segmenting each prosthetic valve, extracting 31 radiomics features from the segmented region, and training a ridge logistic regressor to predict PVE. Training and hyperparameter tuning were done with a cross-validation approach, followed by an evaluation on an independent test database.

RESULTS

A total of 108 patients were included, regardless of myocardial uptake, and were divided into training (n = 68) and test (n = 40) cohorts. Considering the latter, PET-ML findings were positive for 13 of 22 definite PVE cases and 3 of 18 rejected PVE cases (59% sensitivity, 83% specificity), thus leading to an ESC-ML sensitivity of 72% and a specificity of 83%.

CONCLUSIONS

The use of ML for analyzing ¹⁸F-FDG-PET/CT images in PVE diagnosis was feasible and beneficial, particularly when ML was included in the ESC 2015 criteria. Despite some limitations and the need for future developments, this approach seems promising to optimize the role of ¹⁸F-FDG PET/CT in PVE diagnosis.

Epidemiology of infective endocarditis: novel aspects in the twenty-first century

INTRODUCTION

The epidemiology of infective endocarditis (IE) in this millennium has changed with emergence of new risk factors and reemergence of others. This, coupled with modifications in national guidelines in the setting of a pandemic, prompted an address of the topic.

AREAS COVERED

Our goal is to provide a contemporary review of IE epidemiology considering changing incidence of rheumatic heart disease (RHD), cardiac device implantation, and injection drug use (IDU), with SARS-CoV-2 pandemic as the backdrop.

METHODS

PubMed and Google Scholar were used to identify studies of interest.

EXPERT OPINION

Our experience over the past two decades verifies the notion that there is not one 'textbook' profile of IE. Multiple factors have dramatically impacted IE epidemiology, and these factors differ, based, in part on geography. RHD has declined in many areas of the world, whereas implanted cardiovascular devices-related IE has grown exponentially. Perhaps the most influential, at least in areas of the United States, is injection drug use complicating the opioid epidemic. Healthy younger individuals contracting a potentially life-threatening infection has been tragic. In the past year, epidemiological changes due to the COVID-19 pandemic have also occurred. No doubt, changes will characterize IE in the future and serial review of the topic is warranted.

Infective Endocarditis: A Focus on Oral Microbiota

Infective endocarditis (IE) is an inflammatory disease usually caused by bacteria entering the bloodstream and settling in the heart lining valves or blood vessels. Despite modern antimicrobial and surgical treatments, IE continues to cause substantial morbidity and mortality. Thus, primary prevention and enhanced diagnosis remain the most important strategies to fight this disease. In this regard, it is worth noting that for over 50 years, oral microbiota has been considered one of the significant risk factors for IE. Indeed, among the disparate recommendations from the American heart association and the European Society of Cardiology, there are good oral hygiene and prophylaxis for high-risk patients undergoing dental procedures. Thus, significant interest has grown in the role of oral microbiota and it continues to be a subject of research interest, especially if we consider that antimicrobial treatments can generate drug-resistant mutant bacteria, becoming a severe social problem. This review will describe the current knowledge about the relationship between oral microbiota, dental procedures, and IE. Further, it will discuss current methods used to prevent IE cases that originate from oral pathogens and how these should be focused on improving oral hygiene, which remains the significant persuasible way to prevent bacteremia and systemic disorders.

Differentiating Takotsubo cardiomyopathy from ST-segment elevation myocardial infarction

Background:

Takotsubo cardiomyopathy affects between 1.7% and 2.2% of patients hospitalized with suspected acute coronary syndromes. Characterized by chest pain, electrocardiogram changes, and transient left ventricular apical wall motion abnormality, it is under-recognized and often misdiagnosed.

Objectives:

In order to better differentiate between St-segment myocardial infarction and Takotsubo cardiomyopathy, we developed a scoring system.

Methods:

Of the 82 patients enrolled with Takotsubo cardiomyopathy, 67 had ST-segment elevation on electrocardiogram and were compared with 79 ST-elevation myocardial infarction patients. A multi-variant logistic regression model was used to find factors independently associated with Takotsubo cardiomyopathy. The Platelets and Thrombosis in Sheba (PLATIS)-Takotsubo cardiomyopathy is based on a 10-point scoring system: stressful events (3), females (2), no history of diabetes mellitus (2), estimated left ventricular ejection fraction ≤ 40% on admission echo (1), positive troponin on admission (1), and no smoking (1). Patients with Takotsubo cardiomyopathy were older (66 ± 11 vs 60 ± 11 years, p < 0.001), predominantly female (90% vs 15%, p < 0.001), with a lower incidence of diabetes mellitus, dyslipidemia, and smoking. Nevertheless, in-hospital mortality was similar in both groups.

Results:

In a multivariate logistic regression analysis, the average Platelets and Thrombosis in Sheba-Takotsubo cardiomyopathy scoring was significantly higher in Takotsubo cardiomyopathy compared with ST-elevation myocardial infarction patients (8.35 ± 1.7 vs 3.42 ± 1.6, p < 0.001). With an overall score of ≥7, the receiver-operating characteristic curve was 0.82 with a sensitivity of 75% and a specificity of 89% (positive predictive value = 85% and negative predictive value = 80%).

Conclusion:

The Takotsubo cardiomyopathy scoring system is a simple, reliable tool that can assist in diagnosing and differentiating between patients with Takotsubo cardiomyopathy and those with ST-elevation myocardial infarction.

Successful treatment of acute renal failure secondary to complicated infective endocarditis by peritoneal dialysis: a case report

BACKGROUND

Infective endocarditis is one of the most common infections among intravenous drug addicts. Its complications can affect many systems, and these can include acute renal failure. There is a scarcity of cases in the literature related to acute renal failure secondary to infective endocarditis treated with peritoneal dialysis. In this paper, the case of a 48-year-old Saudi male is reported, who presented with features suggestive of infective endocarditis and who developed acute kidney injury that was treated successfully with high tidal volume automated peritoneal dialysis. To our knowledge, this is the second report of such an association in the literature.

CASE PRESENTATION

A 48-year-old Saudi gentleman diagnosed to have a glucose-6-phosphate dehydrogenase deficiency and hepatitis C infection for the last 9 years, presented to the emergency department with a history of fever of 2 days' duration. On examination: his temperature = 41 °C, there was clubbing of the fingers bilaterally and a pansystolic murmur in the left parasternal area. The results of the blood cultures and echocardiogram were supportive of the diagnosis of infective endocarditis, and the patient subsequently developed acute kidney injury, and his creatinine reached 5.2 mg/dl, a level for which dialysis is essential for the patient to survive.

CONCLUSION

High tidal volume automated peritoneal dialysis is highly effective as a renal replacement therapy in acute renal failure secondary to infective endocarditis if no contraindication is present.

Assesment of the Duke criteria for the diagnosis of infective endocarditis after twenty-years. An analysis of 241 cases

BACKGROUND AND AIMS

In the absence of classical features (fever, cardiac murmur, and peripheral vascular stigmata) the diagnosis of infective endocarditis (IE) may be difficult. Current clinical guidelines for the diagnosis and management of IE recommend the use of modified Duke criteria. Correct and prompt diagnosis of IE is crucial for the treatment and outcome of the patients. The aim of this study was to evaluate the presence and the individual value of each criterion of the modified Duke criteria in our patients with infective endocarditis.

METHODS

We performed a prospective observational study between January 2008 - June 2014, in which we enrolled consecutive adult patients admitted for suspicion of IE to the Hospital of Infectious Diseases and at the Heart Institute . We used and extensive database in order to collect demographic data, laboratory and echocardiography results, evolution and outcome of the patients. Using the modified Duke criteria we identified 3 categories of IE: definite, possible and rejected. In order to evaluate the importance of each criterion in the diagnosis of IE we tested two hypotheses. First, we excluded each criterion from the final diagnosis and we counted how many cases felt into a lower category. Second, after adding each major and minor criterion, we tested how many cases would have been classifiable as definite IE.

RESULTS

The study included 241 adult patients with a mean age 58.16 years and sex ratio male/female 1.94. According to the modified Duke criteria 137 patients had definite IE, 79 patients had possible IE and 25 cases had rejected IE We had blood cultures positive IE in 109 cases and blood culture negative IE (BCNE) in 132 (71.21%) cases. Antibiotic treatment prior to blood culture was recorded in 152 (63.07%) patients. In the absence of the echocardiography major criterion, 43% of cases would become possible. After extraction of major microbiological criterion, only one third of definite cases would become possible. Minor criteria such as fever and predisposition contributed to the diagnosis only in 10% of cases. In the presence of vascular or immunological phenomena, or in the presence of minor microbiological criterion, half of the possible IE cases could become possible.

CONCLUSION

Twenty-years after their launch, the Duke criteria for the diagnosis of IE continue to be important tools. Low index of suspicion of IE and inappropriate use of antibiotics may have a great negative impact on the diagnosis of IE. Nowadays, the scarcity of classical Osler manifestations - bacteremia, fever and peripheral stigmata - makes the diagnosis of IE a challenge.

Clinical epidemiology in Italian Registry of Infective Endocarditis (RIEI): Focus on age, intravascular devices and enterococci

INTRODUCTION

The epidemiology of infective endocarditis (IE) is changing due to a number of factors, including aging and health related comorbidities and medical procedures. The aim of this study is to describe the main clinical, epidemiologic and etiologic changes of IE from a large database in Italy.

METHODS

We prospectively collected episodes of IE in 17 Italian centers from July 2007 to December 2010.

RESULTS

We enrolled 677 patients with definite IE, of which 24% health-care associated. Patients were male (73%) with a median age of 62 years (IQR: 49-74) and 61% had several comorbidities. One hundred and twenty-eight (19%) patients had prosthetic left side IE, 391 (58%) native left side IE, 94 (14%) device-related IE and 54 (8%) right side IE. A predisposing cardiopathy was present in 50%, while odontoiatric and non odontoiatric procedures were reported in 5% and 21% of patients respectively. Symptoms were usually atypical and precocious. The prevalent etiology was represented by Staphylococcus aureus (27%) followed by coagulase-negative staphylococci (CNS, 21%), Streptococcus viridans (15%) and enterococci (14%). CNS and enterococci were relatively more frequent in patients with intravascular devices and prosthesis and S. viridans in left native valve. Diagnosis was made by transthoracic and transesophageal echocardiography in 62% and 94% of cases, respectively. The in-hospital mortality was 14% and 1-year mortality was 21%.

CONCLUSION

The epidemiology is changing in Italy, where IE more often affects older patients with comorbidities and intravascular devices, with an acute onset and including a high frequency of enterococci. There were few preceding odontoiatric procedures.

Infective Endocarditis

Infective endocarditis (IE) is a noncontagious infection of the endocardium and heart valves. The epidemiology of IE has shifted recently with an increase in health care-associated IE. Infective endocarditis requiring intensive care unit stay is increasing, and nosocomial IE is frequently responsible. Diagnosis of IE requires multiple clinical data points encompassing history and physical examination, microbiology, and cardiac imaging as no one test is sufficiently sensitive or specific. The modified Duke criteria algorithm is the standard of care in the clinical diagnosis of IE. Complications from IE are common, particularly so in the critical care setting, and include congestive heart failure, embolism, septic shock, invasive infection, prosthetic valve dehiscence, heart block, and mycotic aneurysm. A multidisciplinary care team of infectious disease, cardiology, and cardiac surgery physicians is recommended to reduce complications. Intravenous antibiotics are first-line therapy with cardiac surgery being reserved for certain complications of IE and/or for clinical situations in which there is a high risk of complications. Timing of surgery for IE remains controversial and depends on a variety of clinical factors.

Reassessment of blood culture-negative endocarditis: its profile is similar to that of blood culture-positive endocarditis

INTRODUCTION AND OBJECTIVES

Left-sided infective endocarditis with blood culture-negative has been associated with delayed diagnosis, a greater number of in-hospital complications and need for surgery, and consequently worse prognosis. The aim of our study was to review the current situation of culture-negative infective endocarditis.

METHODS

We analyzed 749 consecutive cases of left-sided infective endocarditis, in 3 tertiary hospitals from June 1996 to 2011 and divided them into 2 groups: group I (n=106), blood culture-negative episodes, and group II (n=643) blood culture-positive episodes. We used Duke criteria for diagnosis until 2002, and its modified version by Li et al. thereafter.

RESULTS

Age, sex, and comorbidity were similar in both groups. No differences were found in the proportion of patients who received antibiotic treatment before blood culture extraction between the 2 groups. The interval from symptom onset to diagnosis was similar in the 2 groups. The clinical course of both groups during hospitalization was similar. There were no differences in the development of heart failure, renal failure, or septic shock. The need for surgery (57.5% vs 55.5%; P=.697) and mortality (25.5% vs 30.6%; P=.282) were similar in the 2 groups.

CONCLUSIONS

Currently, previous antibiotic therapy is no longer more prevalent in patients with blood culture-negative endocarditis. This entity does not imply a delayed diagnosis and worse prognosis compared with blood culture-positive endocarditis. In-hospital clinical course, the need for surgery and mortality are similar to those in patients with blood culture-positive endocarditis. Full English text available from:www.revespcardiol.org.

Impact of prior antibiotic use in culture-negative endocarditis: review of 86 cases from southern Pakistan

BACKGROUND

A large number of patients treated at our hospital for endocarditis have negative cultures. Taking into consideration the fact that many of these patients receive antibiotics prior to referral, we decided to study culture-negative endocarditis in Pakistan.

METHODS

The medical records of all patients admitted to the Aga Khan University Hospital, Pakistan, for the period from 1988 to 2001, with an underlying diagnosis of infective endocarditis (IE) and negative cultures, were reviewed.

RESULTS

Of the 159 patients diagnosed with IE by revised Duke criteria, 86 (54.1%) had persistent negative cultures. More than half of these patients (52%) had received antibiotics before being referred to our center. Patients with culture-negative endocarditis were less likely to be classified as definite endocarditis by revised Duke criteria (p<0.001, 95% CI 0.07-0.3) or to have large vegetations (p=0.021, 95% CI 0.05-0.5), and more likely to have a mitral valve prolapse (p=0.003, 95% CI 1.6-2.3). Definite endocarditis (p=0.042, 95% CI 1.02-7.4), heart failure (p=0.008, 95% CI 1.4-12.7), renal failure (p=0.017, 95% CI 1.16-40.7), embolism (p=0.019, 95% CI 1.2-38.8), and neurological complications (p=0.02, 95% CI 1.16-9.2) were associated with an increased mortality.

CONCLUSION

Culture-negative endocarditis is very common among patients with IE in Pakistan. The presentation, laboratory findings, and complications are similar to those for culture-positive endocarditis. It is postulated that previous antibiotic treatment is the most common cause of culture-negative endocarditis in our hospital.

Infective endocarditis in drug addicts: role of HIV infection and the diagnostic accuracy of Duke criteria

BACKGROUND

Intravenous drug users (IVDUs) are at increased risk of infective endocarditis. Moreover, HIV infection is common in IVDUs, with a reported prevalence of 40-90%. The clinical features of IVDUs with infective endocarditis and HIV infection may be peculiar. Few data have been reported on the diagnostic accuracy of Duke criteria in IVDUs with or without HIV infection, and a comparison of these two populations is lacking.

METHODS

The present study aimed to compare prospectively the clinical features of patients with infective endocarditis with or without HIV infection and to evaluate the diagnostic accuracy of Duke criteria in these patients. The study population consisted of 201 consecutive adult IVDUs with a suspected infective endocarditis (102 patients with HIV infection and 99 patients without HIV infection).

RESULTS

Infective endocarditis was the final diagnosis in 40 of 102 patients (38.2%) with HIV infection and in 55 of 99 HIV-negative patients (55.6%). Despite similar baseline features, longer vegetations were recorded in infective endocarditis without HIV infection (23.7 +/- 7.1 mm versus 13.6 +/- 6.8 mm; P = 0.001). Patients with infective endocarditis and HIV infection had a higher total mortality at 2 months (respectively 12.5% versus 1.8%; P = 0.09); almost all the deaths were recorded in patients with AIDS or a CD4 cell count below 200 per microl, and no deaths were recorded in patients with HIV infection and a CD4 cell count > 500 per microl.

CONCLUSIONS

Despite no identical clinical features, Duke criteria had a similar sensitivity, specificity and diagnostic accuracy in IVDUs with and without HIV infection.

Infective endocarditis in Europe: lessons from the Euro heart survey

OBJECTIVES

To describe the characteristics, treatment, and outcomes of active infective endocarditis (IE) in Europe.

DESIGN

Prospective survey of medical practices in Europe.

SETTING

92 centres from 25 countries.

PATIENTS

The EHS (Euro heart survey) on valvar heart disease (VHD) enrolled 5001 adult patients between April and July 2001. Of those, 159 had active IE.

RESULTS

118 patients (74%) had native IE and 41 (26%) had prosthetic IE. Mean (SD) age was 57 (16) years. Blood cultures were obtained for 113 patients (71%) before antibiotic treatment was started. Surgery was performed in 52% of patients. Reasons for surgery were heart failure in 60%, persistent sepsis in 40%, vegetation size in 48%, or embolism in 18%. Surgery was for implantation of mechanical prosthesis in 63%, bioprosthesis in 21%, aortic homograft in 5%, and valve repair in 11%. In-hospital mortality was 12.6%, being 10.4% in the medical group and 15.6% in the surgical group. Among the total population of 5001 patients, only 50% of those with native VHD had been educated on endocarditis prophylaxis and only 33% regularly attended dental follow up. Of patients with IE who had had a procedure at risk during the preceding year only 50% had received adequate prophylaxis.

CONCLUSIONS

The EHS on VHD shows that patients with active IE have a high risk profile and often undergo surgery. However, there are deficiencies in obtaining blood cultures and applying prophylaxis. Mortality remains high, which is a justification for the improvement of patient management through education and the implementation of guidelines.

Progress toward a global understanding of infective endocarditis. Lessons from the International Collaboration on Endocarditis

In the century and a quarter since William Osler delivered his famed Gulstonian lectures on endocarditis, continual advancements have been made in understanding and treating this disease. Here we have reviewed some key aspects of current knowledge in the areas of population epidemiology, host factors, microorganisms, and diagnosis. The advent of the ICE investigation provides the opportunity to further expand our understanding of IE by developing a very large, global database of IE patients whose clinical, echocardiographic, and microbiologic findings have been characterized with standard methodology. Further, ICE may serve as a rich source of material for investigators seeking to perform specific studies. Finally, the ICE infrastructure creates the opportunity for performing randomized trials to test therapeutic strategies. Although many obstacles remain to be overcome, ICE has created the opportunity for a quantum leap in our knowledge of IE over the next 25 years.

Does assessment of pretest probability of disease improve the utility of echocardiography in suspected endocarditis in children?

OBJECTIVE

To compare the yield rate (YR) of echocardiography when evaluating children with suspected infectious endocarditis (IE) in both the actual clinical setting and in the hypothetic setting where strict clinical criteria are applied. Study design Medical records of 101 children undergoing echocardiography for suspected IE were reviewed. Echocardiograms with positive findings were identified and the actual diagnostic YR was calculated. With the use of clinical criteria proposed by von Reyn (VR), the probability of IE was retrospectively classified as (1) rejected, (2) possible, or (3) probable. Theoretic YR of echocardiography was calculated for each classification.

RESULTS

The actual YR of echocardiography was 12% (12/101). The YR of echocardiography by VR class was 0% in rejected, 20% in possible, and 80% in probable cases (chi(2) = 55.1, P <.0001). Echocardiography did not change the probability of IE in any patient classified as rejected, but allowed reassignment of disease probability in a significant proportion of patients with possible or probable IE.

CONCLUSIONS

The YR of echocardiography was significant when clinical probability of IE was intermediate-to-high, and low, with marginal clinical utility, when clinical probability was low. Strict pretest assessment of disease probability may lead to more effective utilization of echocardiography in this population.

Infective endocarditis in the injection drug user

Although infective endocarditis is certainly not the most common infection seen in injecting drug users, it is the infection that clinicians most commonly think of when they consider infectious complications of injected drug use. The microbiology of infective endocarditis in injection drug users has remained relatively stable over the last several decades. Tricuspid valve endocarditis has been associated most frequently with injection drug use, but recent reports have suggested that involvement of left-sided valves is seen more often now than in the past. The use of transesophageal echocardiography has greatly advanced the ability to diagnose infective endocarditis and the cardiac complications of valvular infection.

Better prognosis of elderly patients with infectious endocarditis in the era of routine echocardiography and nonrestrictive indications for valve surgery

OBJECTIVE

It has been reported that endocarditis in the elderly may have a poor outcome. Our aim was to assess the different features and prognosis, if any, in the present time.

METHODS

Of 103 patients with proven endocarditis, 31 were 65 years or older and 72 were younger than 65 years. Degenerative heart disease was seen more frequently in the elderly (22.5% vs 2.7%, P =.003). Drug abuse and immunodeficiency virus infection were more common in the younger group, as was tricuspid endocarditis (26.3% vs 0%, P <.001). At clinical presentation cardiac failure (41.9 vs 19.4%, P =.02) and leukocytosis (61.2% vs 40.2%, P =.049) were seen more frequently in the elderly.

RESULTS

Despite other similar clinical features, it took longer to diagnose older patients (7.2 +/- 6.2 vs 3.2 +/- 3.5 days, P <.001). Enterococcus infected the aged more often (32.2% vs 13.1%, P =.001). During hospitalization, heart failure and embolization tended to be more common in the elderly and the younger group, respectively. There were no significant differences in the incidence of anatomic complications, the need for operation, and overall mortality.

CONCLUSION

Although a worse prognosis has been reported in elderly patients with infective endocarditis, the early use of transesophageal echocardiographic examinations and equal therapeutic options provides a similar outcome when compared with younger subjects.

Progress toward a global understanding of infective endocarditis. Early lessons from the International Collaboration on Endocarditis investigation

In the century and a quarter since William Osler delivered his framed lectures on endocarditis substantial advancements have occurred in the understanding and treatment of this disease. This article summarizes current understanding of endocarditis in the areas of population epidemiology, host factors, microorganisms, diagnosis, and therapy. In addition, the authors discuss possible directions for investigation in the future, including a new multinational consortium, the International Collaboration on Endocarditis (ICE). This collaboration aims to provide a mechanism to advance the understanding of endocarditis in areas difficult to study without an established network. The multinational nature of the collaboration may also permit a more global view of IE and provide opportunities for studies such as randomized trials of therapeutic treatment strategies.

A retrospective review of 228 episodes of infective endocarditis where rheumatic valvular disease is still common

Two hundred and twenty-eight episodes of infective endocarditis in adult patients (mean age 36 years) were reviewed retrospectively. There were 183 episodes (80%) of native valve, 15 (7%) early prosthetic valve and 30 (13%) late prosthetic valve endocarditis. The most common predisposing factor was rheumatic valvular disease (65%). None of the patients were intravenous drug users. According to the Duke criteria, the number of definite, probable and rejected episodes were 121 (53%), 94 (41%) and 13 (6%), respectively. Additional minor criteria increased the number of definite endocarditis to 82%. The Duke criteria are not primarily intended to influence treatment decisions but are helpful in standardising research activities. The choice of the level of sensitivity or specificity of the criteria may be adjusted according to the aim of the study and prevalence of disease in a particular area. More sensitive criteria may be valuable in those countries where the prevalence of rheumatic valvular disease is still high.

Diagnosis of culture-negative endocarditis: the role of the Duke criteria and the impact of transesophageal echocardiography

BACKGROUND

The Duke criteria have been shown to be more sensitive than the von Reyn criteria in the diagnosis of culture-positive endocarditis but to date have not been fully validated for culture-negative endocarditis (CNE). The aim of this study was (1) to compare the diagnostic accuracy of the Duke criteria versus clinical judgment and the von Reyn criteria in CNE and (2) to assess the diagnostic impact of transesophageal echocardiography (TEE) on the Duke criteria in CNE.

METHODS

The study group consisted of 49 patients with suspected CNE in whom the presence (n = 32) or absence (n = 17) of endocarditis was confirmed by surgery, autopsy, or both. All patients underwent transthoracic echocardiography (TTE) and TEE. They were classified into a Duke category initially with TTE data only, and then the Duke categories were reevaluated with the additional TEE data.

RESULTS

The Duke criteria demonstrated a significantly higher sensitivity (72%) than the von Reyn criteria (28%; P =.0008) and a higher specificity (100%) than clinical judgment (76%; P =.02). No major differences were noted between sensitivities of the Duke criteria and clinical judgement. TEE significantly augmented the capacity to diagnose CNE by Duke criteria versus TTE (P <.05).

CONCLUSIONS

The Duke criteria are of high diagnostic validity for the conduction of clinical studies on CNE. They have the potential to affect clinical decision-making, based on the higher specificity versus clinical judgment. TEE appears to be crucial for the diagnosis of CNE when the Duke criteria are applied. The diagnostic differentiation between CNE, sclerotic valve degeneration, and nonbacterial thrombotic endocarditis remains a challenge.

Transesophageal echocardiography (TEE) in the evaluation of infective endocarditis

Echocardiography is an essential tool for the modern diagnosis and management of infective endocarditis and its complications. The negative predictive value of surface imaging is inadequate to rule out endocarditis in most instances; diagnostic sensitivity is improved by way of the transesophageal approach. The clinical scenario and pretest probability of disease should guide the use of transesophageal versus transthoracic imaging. Those at high risk for endocarditis or its complications in particular should undergo early TEE. Serial studies may be required to guide management. In the setting of an initially negative echocardiographic study, a repeat examination is indicated if the clinical suspicion of endocarditis persists or if the clinical picture changes. Combined transthoracic echocardiography and TEE may supply complementary information useful in management and follow-up. As most published research predates recent advances in imaging, the impact of changing technology, such as harmonic and three-dimensional imaging, in the management of endocarditis is yet to be determined.

Proposed modifications to the Duke criteria for the diagnosis of infective endocarditis

Although the sensitivity and specificity of the Duke criteria for the diagnosis of infective endocarditis (IE) have been validated by investigators from Europe and the United States, several shortcomings of this schema remain. The Duke IE database contains records collected prospectively on >800 cases of definite and possible IE since 1984. Databases on echocardiograms and on patients with Staphylococcus aureus bacteremia at Duke University Medical Center are also maintained. Analyses of these databases, our experience with the Duke criteria in clinical practice, and analysis of the work of others have led us to propose the following modifications of the Duke schema. The category "possible IE" should be defined as having at least 1 major criterion and 1 minor criterion or 3 minor criteria. The minor criterion "echocardiogram consistent with IE but not meeting major criterion" should be eliminated, given the widespread use of transesophageal echocardiography (TEE). Bacteremia due to S. aureus should be considered a major criterion, regardless of whether the infection is nosocomially acquired or whether a removable source of infection is present. Positive Q-fever serology should be changed to a major criterion.

Echocardiography for the Diagnosis of Staphylococcus aureus Infective Endocarditis

Staphylococcus aureus bacteremia (SAB) is a serious and growing problem. A longstanding controversy in infectious diseases has centered around the duration of therapy for patients with SAB. Fortunately, the refinement of echocardiography and the creation of new diagnostic criteria have aided in the diagnosis of infective endocarditis in patients with SAB. These advancements have resulted in the development of an algorithm that combines clinical, microbiologic, and echocardiographic findings to stratify patients with SAB into different treatment regimens.

Value and limitations of the Duke criteria for the diagnosis of infective endocarditis

OBJECTIVES

The purpose of this study was to assess the value and limitations of Duke criteria for the diagnosis of infective endocarditis (IE).

BACKGROUND

Duke criteria have been shown to be more sensitive in diagnosing IE than the von Reyn criteria, but the diagnosis of IE remains difficult in some patients.

METHODS

Both classifications were applied in 93 consecutive patients with pathologically proven IE. Blood cultures, and transthoracic and transesophageal echocardiography were performed in all patients.

RESULTS

Sensitivities for the diagnosis of IE were 56% and 76% for von Reyn and Duke criteria, respectively. Fifty-two patients were correctly classified as "probable IE" by von Reyn and "definite IE" by Duke criteria (group 1). However, discrepancies were observed in 41 patients. Eleven patients (group 2) were misclassified as "rejected" by von Reyn, but were "definite IE" by Duke criteria; this difference could be explained by negative blood cultures and positive echocardiogram in all patients. In eight patients (group 3), the diagnosis of IE was "possible" by von Reyn but "definite" by Duke criteria. This difference was essentially explained by the failure of the von Reyn classification to consider echocardiographic abnormalities as major criteria. Twenty-two patients (group 4) were misclassified as possible IE using Duke criteria, being false negative of this classification. Echocardiographic major criteria were present in 19 patients, but blood cultures were negative in 21 patients. The cause of negative blood cultures was prior antibiotic therapy in 11 patients and Q-fever endocarditis diagnosed by positive serology in three cases.

CONCLUSIONS

Twenty-four percent of patients with proved IE remain misclassified as "possible IE" despite the use of Duke criteria, especially in cases of culture-negative and Q-fever IE. Increasing the diagnostic value of echographic criteria in patients with prior antibiotic therapy and typical echocardiographic findings and considering the serologic diagnosis of Q fever as a major criterion would further improve the clinical diagnosis of IE.

Eustachian Valve Endocarditis in an Elderly Woman

We describe the transesophageal echocardiographic findings in Eustachian valve endocarditis for a 73-year-old woman with a previous history of mitral valve disease. After a 4-week treatment with antibiotics, follow-up echocardiographic examination showed a smaller vegetation.