Diagnostic value of the modified Duke criteria in suspected infective endocarditis -The PRO-ENDOCARDITIS study

Tip of the iceberg: extracardiac CT findings in infective endocarditis

Infective endocarditis (IE) is a disease with high morbidity and mortality rate, but diagnosis is confounded by diverse clinical presentations, which mimic other pathologies. A history of illicit intravenous drug use, previous cardiac valve surgery, and indwelling intracardiac devices increases the risk for developing infective endocarditis. The modified Duke criteria serve as the standard diagnostic tool, though its accuracy is reduced in certain cases. Radiologists in the Emergency Room setting reading body CT may be the first to identify the secondary extra-cardiac complications and facilitate expeditious management by considering otherwise unsuspected infective endocarditis. This review highlights common extracardiac complications of IE and their corresponding CT findings in the chest, abdomen, pelvis, and brain. If IE is suspected radiologists should suggest further investigation with echocardiography.

Impact of Hemoglobin Level, White Blood Cell Count, Renal Dysfunction, and Staphylococcus as the Causative Organism on Prediction of In-Hospital Mortality from Infective Endocarditis

Infective endocarditis (IE) is a highly fatal disease in cases of delayed diagnosis and treatment, although its incidence is low. However, there have been few single-center studies in which the risk of in-hospital death from IE was stratified according to laboratory findings on admission and the organism responsible for IE. In this study, a total of 162 patients who were admitted to our hospital during the period from 2009 to 2021, who were suspected of having IE according to the modified Duke classification, and for whom IE was confirmed by transesophageal echocardiography were retrospectively analyzed. Patients were observed for a mean-period of 43.7 days with the primary endpoint being in-hospital death. The in-hospital death group had a lower level of hemoglobin (Hb), higher white blood cell (WBC) count, lower level of estimated glomerular filtration rate (eGFR), and higher frequency of Staphylococcus being the causative agent than those in the non-in-hospital death group. In overall multivariate analysis, Hb, WBC count, eGFR, and Staphylococcus as the causative agent were identified to be significant prognostic determinants. IE patients with Hb < 10.6 g/dL, WBC count > 1.4 × 104/μL, eGFR < 28.1 mL/minute/1.7 m2, and Staphylococcus as the causative agent had significantly and synergistically increased in-hospital death rates compared to those in other IE patients. Low level of Hb, high WBC count, low eGFR, and Staphylococcus as the causative agent of IE were independent predictors of in-hospital mortality, suggesting that these 4 parameters may be combined to additively stratify the risk of in-hospital mortality.

The Role of Multimodality Imaging in Patients with Congenital Heart Disease and Infective Endocarditis

Infective endocarditis (IE) represents an important medical challenge, particularly in patients with congenital heart diseases (CHD). Its early and accurate diagnosis is crucial for effective management to improve patient outcomes. Multimodality imaging is emerging as a powerful tool in the diagnosis and management of IE in CHD patients, offering a comprehensive and integrated approach that enhances diagnostic accuracy and guides therapeutic strategies. This review illustrates the utilities of each single multimodality imaging, including transthoracic and transoesophageal echocardiography, cardiac computed tomography (CCT), cardiovascular magnetic resonance imaging (CMR), and nuclear imaging modalities, in the diagnosis of IE in CHD patients. These imaging techniques provide crucial information about valvular and intracardiac structures, vegetation size and location, abscess formation, and associated complications, helping clinicians make timely and informed decisions. However, each one does have limitations that influence its applicability.

Native Tricuspid Valve Infective Endocarditis After Breast Skin Abscess

Tricuspid valve infective endocarditis is a rare disease in non-intravenous drug users. It can occur with congenital heart disease, foreign bodies such as central venous catheters and intracardiac devices, and in immunocompromised patients. In the present case, there was a left-sided breast abscess associated with tricuspid valve endocarditis in a patient without any apparent underlying causative factors. We present a case of a young female in her early 20s who arrived at the emergency department with complaints of fever, epistaxis, and vomiting. On clinical examination, she was found to have a fading 2 cm pinkish left breast skin lesion, which had formed on her breast 10 days ago. Blood cultures identified methicillin-resistant Staphylococcus aureus in the blood. A CT scan of the chest, abdomen, and pelvis revealed splenomegaly and an infective focus in the spleen. Subsequent echocardiography confirmed the diagnosis of infective endocarditis of the native tricuspid valve, which was treated with intravenous vancomycin. There was no history of intravenous drug abuse, congenital heart disease, placement of an intracardiac device, central venous catheter, or an immunocompromised state in this patient. Therefore, the diagnosis of infective endocarditis, characterized by a native tricuspid valve vegetation identified as a consequence of a left breast skin abscess, was made. A high index of suspicion is required for a non-specific presentation of tricuspid valve infective endocarditis and in the absence of any prior history of risk factors for right-sided infective endocarditis. Timely initiation of antibiotics depends on a preliminary clinical diagnosis.

Increasing numbers and complexity of Staphylococcus aureus bloodstream infection-14 years of prospective evaluation at a German tertiary care centre with multi-centre validation of findings

OBJECTIVES

Staphylococcus aureus bloodstream infection (SAB) is a common and severe infection. This study aims to describe temporal trends in numbers, epidemiological characteristics, clinical manifestations, and outcomes of SAB.

METHODS

We performed a post-hoc analysis of three prospective SAB cohorts at the University Medical Centre Freiburg between 2006 and 2019. We validated our findings in a large German multi-centre cohort of five tertiary care centres (R-Net consortium, 2017-2019). Time-dependent trends were estimated using Poisson or beta regression models.

RESULTS

We included 1797 patients in the mono-centric and 2336 patients in the multi-centric analysis. Overall, we observed an increasing number of SAB cases over 14 years (6.4%/year and 1000 patient days, 95% CI: 5.1% to 7.7%), paralleled by an increase in the proportion of community-acquired SAB (4.9%/year [95% CI: 2.1% to 7.8%]) and a decrease in the rate of methicillin-resistant-SAB (-8.5%/year [95% CI: -11.2% to -5.6%]). All of these findings were confirmed in the multi-centre validation cohort (6.2% cases per 1000 patient cases/year [95% CI: -0.6% to 12.6%], community-acquired-SAB 8.7% [95% CI: -1.2% to 19.6%], methicillin-resistant S. aureus-SAB -18.6% [95% CI: -30.6 to -5.8%]). Moreover, we found an increasing proportion of patients with multiple risk factors for complicated/difficult-to-treat SAB (8.5%/year, 95% CI: 3.6% to 13.5%, p < 0.001), alongside an overall higher level of comorbidities (Charlson comorbidity score 0.23 points/year, 95% CI: 0.09 to 0.37, p 0.005). At the same time, the rate of deep-seated foci such as osteomyelitis or deep-seated abscesses significantly increased (6.7%, 95% CI: 3.9% to 9.6%, p < 0.001). A reduction of in-hospital mortality by 0.6% per year (95% CI: 0.08% to 1%) was observed in the subgroup of patients with infectious diseases consultations.

DISCUSSION

We found an increasing number of SAB combined with a significant increase in comorbidities and complicating factors in tertiary care centres. The resulting challenges in securing adequate SAB management in the face of high patient turnover will become an important task for physicians.

Fungal Endocarditis: A Rare Case of Multiple Arterial Embolization

Fungal endocarditis is a rare and fatal condition, with a mortality of up to 75%, affecting immunocompromised hosts with a predisposing condition, namely, a history of previous cardiac or noncardiac surgery. Embolization is frequent, accounting for 44% of cases, and as the most common site is the brain, it can cause leptomeningitis, parenchymal granulomas, or abscesses. This case report describes a man with aortic valve replacement one year ago and a recent carotid endarterectomy who was admitted with fever and neurological deficits. The workup permitted a diagnosis of fungal endocarditis, and the patient underwent a combined and aggressive treatment approach with antifungal therapy and surgery, with a successful replacement of the aortic valve. During hospitalization, the patient's neurological status deteriorated, and a cerebral abscess was discovered on the left frontal lobe. Despite the poor prognosis, the patient recovered slowly and was discharged from the hospital three months later. The present case highlights the high index of suspicion needed for the diagnosis and the need for a multidisciplinary team to approach these patients to achieve a positive outcome.

Infective Endocarditis: Predictive Factors for Diagnosis and Mortality in Surgically Treated Patients

Background: Diagnosis of infective endocarditis (IE) often is challenging, and mortality is high in such patients. Our goal was to characterize common diagnostic tools to enable a rapid and accurate diagnosis and to correlate these tools with mortality outcomes. Methods: Because of the possibility of including perioperative diagnostics, only surgically treated patients with suspected left-sided IE were included in this retrospective, monocentric study. A clinical committee confirmed the diagnosis of IE. Results: 201 consecutive patients (age 64 ± 13 years, 74% male) were finally diagnosed with IE, and 14 patients turned out IE-negative. Preoperative tests with the highest sensitivity for IE were positive blood cultures (89.0%) and transesophageal echocardiography (87.5%). In receiver operating characteristics, vegetation size revealed high predictive power for IE (AUC 0.800, p < 0.001) with an optimal cut-off value of 11.5 mm. Systemic embolism was associated with mortality, and N-terminal prohormone of B-type natriuretic peptide (NT-proBNP) had predictive power for mortality. Conclusion: If diagnostic standard tools remain inconclusive, we suggest employing novel cut-off values to increase diagnostic accuracy and accelerate diagnosis. Patients with embolism or elevated NT-proBNP deserve a closer follow-up.

Infective Endocarditis in High-Income Countries

Infective endocarditis remains an illness that carries a significant burden to healthcare resources. In recent times, there has been a shift from Streptococcus sp. to Staphylococcus sp. as the primary organism of interest. This has significant consequences, given the virulence of Staphylococcus and its propensity to form a biofilm, rendering non-surgical therapy ineffective. In addition, antibiotic resistance has affected treatment of this organism. The cohorts at most risk for Staphylococcal endocarditis are elderly patients with multiple comorbidities. The innovation of transcatheter technologies alongside other cardiac interventions such as implantable devices has contributed to the increased risk attributable to this cohort. We examined the pathophysiology of infective endocarditis carefully. Inter alia, the determinants of Staphylococcus aureus virulence, interaction with host immunity, as well as the discovery and emergence of a potential vaccine, were investigated. Furthermore, the potential role of prophylactic antibiotics during dental procedures was also evaluated. As rates of transcatheter device implantation increase, endocarditis is expected to increase, especially in this high-risk group. A high level of suspicion is needed alongside early initiation of therapy and referral to the heart team to improve outcomes.

Infective Endocarditis With Secondary Headache: A Case Report

Secondary headache is a symptom of an underlying disease. Infective endocarditis (IE) is a serious infection of the heart tissue. Herein, we present a rare case of IE, with a secondary headache. The patient presented with persistent headache, fever of 39°C, myalgia, and painful erythema of the plantar surface of the foot. The headache progressively worsened over a few weeks. She was diagnosed with secondary headache, and sepsis was suspected. Blood culture revealed the presence of Streptococcus viridans, leading to a diagnosis of IE. Postoperatively, the patient recuperated without any complications. Headaches can be secondary to other conditions. Therefore, comprehensive assessment and accurate diagnosis are essential. Dentists must be aware that headache is a concomitant symptom of IE.

Modified Duke/European Society of Cardiology 2015 clinical criteria for infective endocarditis: time for an update?

Background

The diagnosis of infective endocarditis (IE) is based on the modified Duke/European Society of Cardiology (ESC) 2015 clinical criteria. The sensitivity of the criteria is unknown in South Africa, but high rates of blood culture negative endocarditis (BCNIE), coupled with a change in the clinical features of IE, may limit the sensitivity.

Methods

The Tygerberg Endocarditis Cohort study prospectively enrolled patients with IE between November 2019 and June 2021. A standardised protocol for organism detection, with management of patients by an Endocarditis Team, was employed. Patients with definite IE by pathological criteria were analysed to determine the sensitivity of the current clinical criteria.

Results

Eighty consecutive patients with IE were included of which 45 (56.3%) had definite IE by pathological criteria. In patients with definite IE by pathological criteria, 26/45 (57.8%) of patients were classified as definite IE by clinical criteria. BCNIE was present in 25/45 (55.6%) of patients and less than three minor clinical criteria were present in 32/45 (75.6%) of patients. The elevation of Bartonella serology to a major microbiological criterion of the modified Duke/ESC 2015 clinical criteria would increase the sensitivity (57.8% vs 77.8%; p=0.07).

Conclusion

The sensitivity of the modified Duke/ESC 2015 clinical criteria is lower than expected in patients with IE in South Africa, primarily due to the high rates of Bartonella-associated BCNIE. The elevation of Bartonella serology to a major microbiological criterion, similar to the status of Coxiella burnetii in the current criteria, would increase the sensitivity. The majority of patients with definite IE by pathological criteria had less than three minor criteria present.

Clinical prediction scores and the utility of time to blood culture positivity in stratifying the risk of infective endocarditis in Staphylococcus aureus bacteraemia

Background

Infective endocarditis (IE) complicates up to a quarter of Staphylococcus aureus bacteraemia (SAB) cases. Risk scores predict IE complicating SAB but have undergone limited external validation, especially in community-acquired infections and those who use IV drugs. Addition of the time to positive culture (TTP) may provide incremental risk prognostication.

Objectives

To externally validate risk scores for predicting IE in SAB and assess the incremental value of TTP.

Methods

The modified Duke score was calculated for adults hospitalized with SAB at a major tertiary institution. All patients underwent echocardiography. Sensitivity and specificity of the risk scores for predicting IE were calculated, and the incremental value of TTP was assessed.

Results

One hundred and six cases were analysed and 18 (17%) met definite IE criteria. The optimal TTP to predict IE was 11.5 h (sensitivity 88.9%; specificity 71.6%). The sensitivity of VIRSTA and PREDICT (Predicting risk of endocarditis using a clinical tool) were similar (94.4% for both) and higher than POSITIVE (Prediction Of Staphylococcus aureus Infective endocarditis Time to positivity, IV drug use, Vascular phenomena, pre-Existing heart condition; 77.8%). The receiver-operator characteristic AUCs were VIRSTA 0.83, PREDICT 0.75, POSITIVE 0.89 and TTP 0.85. Adding TTP to VIRSTA (i.e. VIRSTA+) resulted in the highest AUC (0.90), sensitivity (100%) and negative predictive value (100%), albeit with a low specificity (33%).

Conclusions

The VIRSTA and POSITIVE scores were the strongest predictors for IE complicating SAB. The addition of TTP to VIRSTA (VIRSTA+) significantly improved discriminatory value and may be safely used to rationalize echocardiography strategies.

Clinical, Microbiological, and Imaging Characteristics of Infective Endocarditis in Latin America: A Systematic Review

OBJECTIVES

We aimed to describe the clinical, microbiological, and imaging characteristics of patients with infective endocarditis (IE) in studies from Latin America (LATAM).

METHODS

A systematic search through PubMed, EMBASE, LILACS, and SciELO from inception until February 2021 was conducted. We included observational studies that assessed adults with IE from LATAM and reported data on clinical, microbiological, or imaging characteristics. Data were independently extracted by 2 authors and the risk of bias was evaluated by study design with its respective tool. Findings were summarized using descriptive statistics.

RESULTS

Forty-four studies were included. Most cases were male (68.5%), had a predisposing condition including valve disease (24.3%), or had a prosthetic valve (23.4%). Clinical manifestations included fever (83.9%), malaise (63.2%), or heart murmur (57.7%). A total of 36.4% and 27.1% developed heart failure or embolism, respectively. Blood cultures were negative in 23.9% and S. aureus (18.6%) and the viridans group streptococci (17.8%) were the most common isolates. Most cases were native valve IE (67.3%) affecting mainly left-sided valves. Echocardiographic findings included vegetations (84.3%) and regurgitation (75.9%). In-hospital mortality was 25.1%.

CONCLUSIONS

This is the first systematic review that evaluated the characteristics of IE in LATAM patients. A lack of multicenter studies reflects the need for these studies in LATAM.