Epidemiologic aspects of infective endocarditis in an urban population. A 5-year prospective study

Structural vaccinology-based design of multi-epitopes vaccine against Streptococcus gordonii and validation using molecular modeling and immune simulation approaches

Streptococcus gordonii is an oral bacterium colonizing the dental cavity and leading to plaque formation. This pervasive colonizer is also the etiologic agent of bacterial endocarditis and has a major role in infective endocarditis. The bacteria reach the heart through oral bleeding, leading to inflammation of cardiovascular valves. Over the past 50 years, it has shown a significant pathogenic role in immunocompromised and neutropenic patients. Since antibiotic resistance has created prophylaxis failure towards infective endocarditis, a potent therapeutic candidate is needed. Therefore, multi-epitopes vaccine offers advantages over the other approaches. Thus, herein, numerous molecular-omics tools were exploited to mine immunogenic peptides, i.e., T-cell and B-cell epitopes, and construct a vaccine sequence. Our findings revealed a total of 24 epitopes, including CTL, HTL, and B-cell are responsible for imparting immune responses, which were combined with the help of different linkers, and MEVC was constructed. Multifactorial validation of the candidate vaccine was performed to minimize the risk factors. The final sequence was docked with TLR2 to validate its conformation compatibility with receptor and long-term interactions stability. Our analysis revealed that the vaccine construct is immunogenic and non-allergenic. The construct also established various contacts with the immune receptor. Finally, the vaccine sequence was reverse-translated, optimized for codon usage, and analyzed for expression in the Escherichia coli K12 strain. Maximum expression was noted with a CAI score of 0.95. In silico immune simulation revealed that the antigen was neutralized on the 3rd day after injection. In conclusion, the current study warrants validation of the vaccine construct both in in vitro and in vivo models for accurate therapeutic intervention.

Getting to the heart of the opioid crisis: Infective endocarditis

ABSTRACT

Infective endocarditis is a potentially fatal infection of the endocardium or valves that can result from IV drug abuse. This article describes a patient with infective endocarditis masked by opioid abuse withdrawal symptoms. This challenging presentation brings to the forefront the need for clinicians to be aware of and understand the changing risk factors and demographics of patients with nonspecific infective endocarditis.

The Epidemiology of Endocarditis in Manitoba: A Retrospective Study

Background

Recently, anecdotal evidence suggested an increase in infective endocarditis (IE) in Manitoba driven by an increasing proportion of patients with intravenous drug use (IVDU)-associated endocarditis. This study aimed to characterize the observed changing incidence and epidemiology of IE.

Methods

This retrospective study evaluated consecutive patients >18 years old with an International Classification of Disease–10 diagnosis of IE who presented to a tertiary referral center in Winnipeg, Manitoba between January 1, 2004 and December 31, 2018. Data were obtained by individual review of paper and electronic medical records and entered into the Research Electronic Data Capture database. Mortality and hospital readmission data were acquired by linking Research Electronic Data Capture data to the Manitoba Centre for Health Policy, which prospectively maintains a comprehensive population-based health database.

Results

A total of 612 cases of IE were identified. The incidence of IE increased from 2.03 per 100,000 in 2004 to 5.16 per 100,000 in 2018, with IVDU-associated cases increasing from 0.11 to 2.87 per 100,000. Left heart vegetations were most common in the non-IVDU group, whereas right-sided vegetations dominated in the IVDU group. All-cause mortality did not differ between IVDU and non-IVDU IE, despite a significantly younger age in patients with IVDU. The IVDU group showed a higher rate of endocarditis recurrence.

Conclusions

In this first study to examine the longitudinal incidence of IE in Manitoba, we showed that the incidence of IE has significantly increased over the last 15 years, with a contribution of IVDU-associated IE that has a high rate of mortality and disease recurrence.

Changing microbiological profile and antimicrobial susceptibility of the isolates obtained from patients with infective endocarditis - The time to relook into the therapeutic guidelines

The microbiological profile, associated risk factors and demographic characteristics of patients with IE has changed in the recent times. In the present study, the antibiotic susceptibility profile of 66 isolates (40 from IDU and 26 from non IDU) recovered over a period of three years from the patients with definitive diagnosis of IE along with their absolute minimum inhibitory concentrations (MIC-μg/ml) was determined as per CLSI, 2017 guidelines. Staphylococcus aureus was found to be the predominant pathogen associated with IE out of which 90.2% isolates were MRSA, although none of the isolates were found resistant to vancomycin, teicoplanin, daptomycin and linezolid. Pseudomonas aeruginosa isolates were 100% susceptible to carbapenams, however variable resistance was observed against other antimicrobials. All Enterococci were found to be 100% susceptible to linezolid and daptomycin, whereas vancomycin resistant enterococci phenotype was observed in 25% of the Enterococcal isolates. A noticeable difference in the antimicrobial susceptibility profile and their MICs were observed in the present study, as compared to published literature across the globe and within the country. However, no statistically significant difference (λ ² test, p > 0.01)in the AST pattern of isolates from IDU vs. Non IDU was observed. After reviewing the local antibiogram it seems that we need to have our own regional guidelines, which may partially replace the currently prevailing AHA/ESC guidelines.

Transcatheter aortic valve implantation in patients with unruptured aortic root pseudoaneurysm: an observational study

AIMS

Unruptured aortic root pseudoaneurysm (UARP) is a rare complication of aortic valve endocarditis. Infectious spread to the valvular annulus or myocardium can cause septic complications that manifest as wall thickening, and spontaneous abscess drainage leads to pseudoaneurysm formation. We report the first patient series in which transcatheter aortic valve implantation (TAVI) using a single valve-resolved aortic valvulopathy associated with UARP was performed.

METHODS

At our center, from December 2017 to October 2019, 138 patients underwent TAVI for aortic valve stenosis and/or regurgitation, 20 of whom (12 female patients, 8 male patients) had associated incidental UARP and were considered as our study population. The average age of these patients was 76.9 ± 5.2 years. All patients were assessed using preprocedural and postprocedural multimodality imaging, including transthoracic echocardiography, transesophageal echocardiography, and cardiac computed tomography angiography (CCTA).

RESULTS

In all cases, the final angiographic examination showed correct valve positioning with complete coverage of the false aneurysm. Post-TAVI CCTA showed presence of total or subtotal UARP thrombosis. The mean follow-up period was 17.5 months (12-23 months). During follow-up, imaging showed normal prosthetic valve function, no significant leakage (trace or mild), and complete UARP exclusion in all patients, without any complications.

CONCLUSION

In conclusion, percutaneous valve positioning can simultaneously solve pseudoaneurysm complications by excluding the sac and promoting thrombosis.

Cumulative incidence of infective endocarditis in patients with congenital heart disease: a nationwide, case-control study over nine decades

BACKGROUND

Congenital heart disease (CHD) is a lifelong predisposing condition for infective endocarditis (IE). As a consequence of advances in pediatric care, the number of adults with CHD is now exceeding the number of children. The goal of the present study was to determine the cumulative incidence of IE in patients with CHD and detect temporal changes compared with controls.

METHODS

Nationwide registry-based case-control study of patients with CHD born 1930-2017 matched with 10 random controls. Infective endocarditis episodes were linked using the Swedish 10-digit personal identification number.

RESULTS

In total, 89,541 patients with CHD and 890,470 matched controls were included. In patients with CHD, 1477 IE episodes were registered and 447 episodes in controls. Patients with CHD had 8.5% cumulative incidence of IE at age 87 years, compared with 0.7% in matched controls. Incidence rate of IE per 100,000 person-years was 65.5 (95% confidence interval [CI] 62.2-68.9) and 1.8 (95% CI 1.7-2.0) in CHD patients and controls, respectively. By age 18 years, patients with CHD had an IE incidence similar to that of 81-year-old controls. Incidence of IE differed by age but not by birth year. Bacterial etiology was registered from 1997 in half of the IE episodes; among CHD IE cases, 43.3% were caused by streptococci, 29.8% by Staphylococcus aureus.

CONCLUSIONS

Infective endocarditis remains an important complication in patients with CHD. Incidence correlate with age and the number of IE episodes are expected to increase as the CHD population grow older.

Long-term Outcomes Are Poor in Intravenous Drug Users Following Infective Endocarditis, Even After Surgery

BACKGROUND

Previous studies of outcomes in people who inject drugs (PWID) with infective endocarditis (IE) have often been retrospective, have had small sample sizes, and the duration of follow-up has been short and limited to patients who were operated on.

METHODS

PWID treated for IE between 1 January 2006 and 31 December 2016 were identified from a prospectively collected database. PWID hospitalized with other infections acted as a novel comparison group. Outcomes were all-cause mortality, cause of death, relapse, recurrence, and reoperation.

RESULTS

There were 105 episodes of IE in 92 PWID and 112 episodes of other infections in 107 PWID in whom IE was suspected but rejected. Survival at 30 days for the IE group was 85%, and 30-day survival following surgery was 96%. The most common pathogens were Staphylococcus species (60%) and Streptococcus species (30%). The surgical intervention rate was 47%. Survival for the IE group at 1, 3, 5, and 10 years was 74%, 63%, 58%, and 44%, respectively. This was significantly lower compared with the comparator group of other infections in PWID (P = .0002). Mortality was higher in patients who required surgery compared with those who did not (hazard ratio, 1.8 [95% confidence interval, .95-3.3]). The commonest cause of death was infection (66%), usually a further episode of IE (55%).

CONCLUSIONS

Although early survival was good, long-term life expectancy was low. This was attributable to ongoing infection risk, rather than other factors known to affect prognosis in PWID. Surgery conferred no long-term survival advantage. More efforts are needed to reduce reinfection risk following an episode of IE in PWID.While early survival for people who inject drugs (PWID) with infective endocarditis is good, long-term survival is poor due to ongoing infection risk. Surgery conferred no long-term survival advantage, so more efforts are needed to reduce reinfection risks for PWID.

A case of infective endocarditis caused by Arthrobacter woluwensis

Corynebacteria are rare causative agents of infective endocarditis. This is a reported case of a destructive aorto-mitral infective endocarditis caused by Arthrobacter woluwensis. Microbial identification was achieved by 16S rRNA polymerase chain reaction on valve tissue samples. Outcome was favorable after surgical valve replacement and 4-week antibiotic treatment.

[Surgical treatment of infective endocarditis: Surgical indications, complications, intrahospital and long-term mortality]

BACKGROUND

In addition to medical treatment, half of the patients with infective endocarditis (IE) receive surgical treatment. Despite clear recommendations on the indications and the operating delays, the decision remains difficult and must take into consideration several factors.

METHODS

A retrospective study was performed at Foch Hospital. All patients operated for IE between 2005 and 2018 were included. Patient characteristics, indications and operating delays, as well as intrahospital mortality, were noted. Patient follow-up was provided by phone calls.

RESULTS

Fifty-two patients were operated on for IE between 2005 and 2018. The most frequent surgical indications were the presence of a massive symptomatic regurgitation, an uncontrolled infection and large vegetations with embolism. The average operative delay was 13.2 days with 56.5% of patients operated within the first 10 days. The most common postoperative complications were acute kidney injury (AKI) in 57.7% of cases, with 9.6% of dialysis, shock in 50% of cases, rhythm disorders in 40.4% of cases, infectious complications in 19.2% of cases, conductive disorders in 25% of cases, of which 17.3% require a definitive pacemaker implementation. The intrahospital mortality was 7.7% and the average length of hospital stay was 35 days. Survival at one year and 5 years was 95% and 85%, respectively.

CONCLUSION

The indications and the operating delays were conformed to international recommendations. Intrahospital and long-term mortality rate was low.

Incidence of infective endocarditis caused by viridans group streptococci in Sweden - effect of cessation of antibiotic prophylaxis in dentistry for risk individuals

Introduction

In October 2012, the Swedish Medical Products Agency published new recommendations for the cessation of prophylactic antibiotics in dentistry for the prevention of infective endocarditis (IE). Previously, 2 g of amoxicillin per os would be administered 1 h before invasive dental procedures to patients with valve prosthesis, complicated heart valve disease, and to those with previous endocarditis.

Objectives

The aim of this study was to evaluate whether the total incidence of IE caused by oral viridans group streptococci (VGS) or IE caused by staphylococci, increased in Sweden after the introduction of the new recommendations.

Methods

The incidence of IE in Sweden before and after October 2012 was calculated and compared using an interrupted time series analysis. Separate analyses were conducted for the total incidence of IE, and IE caused by VGS or Staphylococcus aureus. Cases of IE were identified using the Swedish national registry of IE, which has existed since 1995 and contains data from all Swedish hospital clinics specialising in infectious disease. All cases with hospital admission date from the 1^st of Jan 2008, to the 31^st of Dec 2017 were included. The incidence calculations were corrected for annual changes in population size using data from the Swedish government agency Statistics Sweden.

Results

The results show no statistically significant increase in the slope of the trend line of the total incidence of IE, IE caused by VGS or S. aureus in the Swedish general population after October 2012, compared to before.

Conclusion

The results suggest that the recommended cessation of prophylactic antibiotics for the prevention of IE in dentistry has not led to an increased incidence of IE caused by oral streptococci among the Swedish population.

The epidemiology of infective endocarditis with focus on non-device related right-sided infective endocarditis: A retrospective register-based study in the region of Southern Denmark

AIMS

Non-device related right-sided infective endocarditis (ND-RSIE) is not well characterized. We aimed to characterize patients with infective endocarditis (IE) with emphasis on the epidemiology, clinical characteristics and complications of ND-RSIE.

METHODS

In this population-based cohort study, we identified patients with IE using ICD-10 codes from the Danish National Hospital Register in the Region of Southern Denmark between January 2007 and May 2017. Hospital records were reviewed, and characteristics and outcomes recorded.

RESULTS

We included 1243 confirmed IE episodes of which 82% were left-sided IE, 11% were cardiac device right sided infective endocarditis (RSIE) and 7% were ND-RSIE. Patients with ND-RSIE were considerably younger, had less comorbidity and had a lower 30-day mortality (6%) compared with patients with device RSIE (24%) and left-sided IE (26%) (p<0.01). ND-RSIE was associated with underlying heart disease, involvement of the tricuspid valve (57%), Staphylococcus species (53%) and complications (61%). Forty percent of ND-RSIE occurred among people who inject drugs (PWID) for whom significant differences were observed compared with non-PWID with regards to tricuspid valve involvement (96% vs. 32%), causative microorganisms (Staphylococcus aureus 79% vs. 27%), complications (86% vs. 45%), recurrence (29% vs. 11%) and 30-day mortality (0% vs. 7%).

CONCLUSION

ND-RSIE is relatively rare and differs with regards to epidemiology, clinical characteristics and complications compared with left-sided IE and cardiac device RSIE, but has a favourable prognosis. Forty percent of ND-RSIE occurs among PWID, which is associated with frequent complications but a very low mortality.

The value of an "Endocarditis Team"

Establishment of the Heart Team concept in the field of cardiovascular medicine has resulted in quality improvement in the management of heart valve disease and heart failure. Similarly, the concept of an Endocarditis Team would be important in improving outcomes in patients with infective endocarditis (IE), given it is an uncommon clinical entity with general practitioners and low-volume centers lacking sufficient experience in its management. A multidisciplinary approach can substantially reduce the still unacceptably high morbidity and mortality in patients with IE, as it allows early diagnosis and appropriate comprehensive management. Decision-making within the Endocarditis Team must follow a standard protocol that is based on current clinical guidelines for the management of IE. If surgery is indicated, it is best performed sooner than later in most instances. Communication between referring hospitals and reference centers with an established Endocarditis Team must be smooth and definite protocols for transfer to experienced endocarditis centers with surgical facilities is essential. Follow-up and outpatient care following hospital discharge is crucial due to the possibility of residual infection and risk of development of recurrent endocarditis or heart failure, particularly within the first 2 years. Patient and health-care provider education is the mainstay for the accurate implementation of the Endocarditis Team concept. The following Keynote Lecture offers an overview of the current literature supporting the multidisciplinary management of IE and addresses multiple aspects related to the Endocarditis Team, highlighting its importance and necessity for the comprehensive treatment of this complex disease.

Mitral valve repair in infective endocarditis is not inferior to valve replacement: results from a Spanish nationwide prospective registry

INTRODUCTION

Infective endocarditis (IE) still carries high morbidity and mortality and frequently requires surgery. The benefit of mitral valve repair (MVr) in the setting of IE is yet to be proven. The goal of this study was to assess the results of MVr in patients with IE after a minimum follow-up of 1 year.

METHODS

This study is based on a Spanish nationwide prospective registry that included patients operated on for native mitral valve IE. The collaborating Institutions pooled their pre-, peri-, and postoperative data into the database of the GAMES group [Grupo de Apoyo al Manejo de la EndocarditiS (Group for support and management of infective endocarditis)].

RESULTS

Data from 27 hospitals were recorded and 3524 cases of active IE identified between 2008 and 2016. There were 1513 cases of mitral IE, of which 898 involved native valves. Of these, 437 patients underwent surgical treatment, and 369 completed the 1-year follow-up. The valve was repaired in 68 cases (18.4%). Preoperative groups were comparable (EuroSCORE MVr 7.7 vs MVR 8.0; p = ns). Mortality in the repair group was inferior to that in the replacement group (16.2% vs 27.2%, p = 0.058). At 1 year, mortality remained higher in the replacement group: 3.7% vs 2.9%. Relapse of the infection was slightly more frequent in the repair group (7.1% vs 3.7%; p = ns), although this did not lead to higher rates of reintervention (MVr/MVR: 2.9% vs 4.9%).

CONCLUSION

MVr is an attractive option for specific patients with IE and does not seem to negatively impact on relapses.

High Morbidity and Mortality Among Patients With Sentinel Admission for Injection Drug Use-Related Infective Endocarditis

Background

Hospitalizations for individuals with injection drug use-related infective endocarditis (IDU-IE) represent an increasing portion of all patients with endocarditis. This study describes the evolving trends in demographics, clinical characteristics, rates of surgical intervention, and mortality among patients hospitalized with IE, comparing those with and without injection drug use.

Methods

This is a retrospective cohort study of patients admitted between January 1, 2007 to June 30, 2015 at a tertiary care center in Boston, Massachusetts. Endocarditis was defined by International Classification of Diseases, Ninth Revision code and verified by the modified Duke Criteria for IE. The clinical characteristics, microbiology, site of infection, complications of IE, and outcome were all abstracted by chart review. Rates of surgical consultation and surgical intervention within 90 days of admission were obtained, and assessment of surgical risk calculated was by EuroSCORE II (euroscore.org/calc). Subsequent hospitalizations for all causes were also reviewed.

Results

Injection drug use-related infective endocarditis occurred in younger patients with lower rates of diabetes, renal dysfunction, and prior cardiothoracic (CT) surgery than those without IDU. Injection drug use-related infective endocarditis was associated with higher rates of complications, CT surgery consultation, and surgery within 90 days for absolute surgical indication. Readmissions for endocarditis occurred in 20% of IDU-IE patients and 9% of those with non-IDU IE. All-cause 1-year mortality rates were similar (IDU-IE 16%, non-IDU IE 13%; P = .58).

Conclusions

Despite younger age, fewer medical comorbidities, and fewer prior cardiac surgeries, all-cause 1-year mortality was similar for patients after sentinel admission for IDU-IE compared with non-IDU IE. Interventions in the acute hospital setting and after discharge are needed to support patients with IDU-IE, focusing on harm reduction and treatment of addiction to reduce the unexpectedly high mortality of this young population.

Early results for active infective endocarditis

Introduction

Cardiac surgery is frequently needed during active phase of infective endocarditis (IE). The purpose of this study was to analyze the immediate and late results and determine the risk factors for death.

Methods

We retrospectively reviewed 101 patients with IE operated in the active phase. The mean age was 40.5 ± 12.5 years. 16 patients (15.8%) were diagnosed with prosthetic valve endocarditis (PVE). 81 (80.9%) were in NYHA functional class III-IV. Blood cultures were positive in only 24 cases (23.9%).

Results

in-hospital mortality rate was 17.9% (18 cases). Multivariate analysis indentified five determinant predictor factors: congestive heart failure (CHF), renal insufficiency, high Euroscore, prolonged cardiopulmonary bypass time (> 120 min) and long ICU stay. The median follow-up period was 4.2 (2-6.5) years. Overall survival rate for all patients who survived surgery was 97% at 5 years and 91% at 10 years.

Conclusion

Despite high in-hospital mortality rate, when patients receive operation early in the active phase of their illness, late outcome may be good.

Aortic root replacement with cryopreserved homograft for infective endocarditis in the modern North American opioid epidemic

OBJECTIVE

To study mid-term survival in patients with infective endocarditis as a result of IV drug use undergoing aortic root replacement with cryopreserved aortic homograft.

METHODS

Patients undergoing aortic root homograft replacement from 2011-2017 were studied retrospectively. Aortic root replacement was performed using a modified Bentall technique. Primary outcomes included both short-term and mid-term survival. Secondary outcomes included immediate postoperative complications.

RESULTS

A total of 138 patients underwent cryopreserved homograft replacement of the aortic root for aortic root abscesses. Eighty-five patients (61.6%) underwent reoperative sternotomy, and 12 patients (8.7%) underwent second or third reoperative sternotomy. Sixty-seven (48.5%) patients had severe aortic insufficiency preoperatively. Operative mortality was 12.3% (17 patients). Five patients (3.6%) sustained a permanent stroke. Twenty-one patients (15.2%) required dialysis for renal failure, and 21 patients (15.2%) had complete heart block necessitating a permanent pacemaker. Estimated 5-year mortality for the cohort was 43%.

CONCLUSIONS

Cryopreserved homograft replacement is a safe and desirable option for high-risk patients with infective endocarditis and aortic root abscess. Homograft accommodation for a widely debrided aortic annular bed provides a reasonable surgical strategy for patients needing aortic root replacement with annular abscess.

A rare cause of healthcare-associated infective endocarditis: Enterobacter cloacae

We report a case of infective endocarditis secondary to healthcare-associated bloodstream infection caused by an uncommon etiologic agent, multidrug-resistant Enterobacter cloacae. The patient was treated with a combination of antimicrobial therapy and surgery, but could not be saved. With this case, we discuss the prevalence, risk factors, treatment options, and outcomes of the rarely encountered Enterobacter cloacae-associated infective endocarditis.

Staphylococcal versus Streptococcal infective endocarditis in a tertiary hospital in Belgium: epidemiology, clinical characteristics and outcome

Infective endocarditis (IE) is a rare but serious illness associated with a high mortality. Staphylococcus spp and Streptococcus spp are the most frequent causative pathogens. In this study, we compared the epidemiology, clinical characteristics and outcomes of patients with Staphylococcal and Streptococcal IE in a tertiary hospital. Using our institutional database 'Medical Explorer', we collected all cases of IE retrospectively between January 2005 and December 2010 at the Cliniques Universitaires Saint Luc and then focused on Staphylococcal and Streptococcal IE. Of the 212 patients with IE included in our study, Staphylococcus spp accounted for 35.9% (76/212) of the cases, Streptococcus spp for 35.4% (75/212) and the remainder 18% (61/212) of cases were caused by other pathogens. Negative blood culture IE accounted for 10.4% of all cases. Demographic and clinical characteristics such as age, gender, fever, presence of a heart murmur, heart failure, nature of the affected valve, location of the endocarditis, duration of antibiotics, length of stay and complication were not different when comparing Staphylococcal and Streptococcal IE; only mortality differed. The mortality rate was 21.4 and 6.6% (p = 0.02) for Staphylococcal and Streptococcal IE, respectively. In the multivariate analysis, age >60 years, Staphylococcal IE, presence of complications and absence of surgery were independent risk factors for mortality.

Staphylococcus aureus bacteraemia and endocarditis - epidemiology and outcome: a review

PURPOSE

To review the epidemiology of Staphylococcus aureus bacteraemia (SAB) and endocarditis (SAE), and discuss the short- and long-term outcome.  Materials and methods: A literature review of the epidemiology of SAB and SAE.

RESULTS

The reported incidence of SAB in Western countries is 16-41/100,000 person-years. Increasing incidence has been observed in many regions, in Iceland by 27% during 1995-2008. The increase is believed to depend on changes in population risk factors and possibly better and more frequent utilization of diagnostic procedures. S. aureus is now the leading causes of infective endocarditis (IE) in many regions of the world. It accounts for 15-40% of all IE cases, and the majority of cases in people who inject drugs (PWID). Recently, the incidence of SAE in PWID in Stockholm, Sweden, was found to be 2.5/1000 person-years, with an in-hospital mortality of 2.5% in PWID as compared to 15% in non-drug users. The 30-day mortality associated with SAB amounts to 15-25% among adults in Western countries, but is lower in children (0-9%). Mortality associated with SAE is high (generally 20-30% in-hospital mortality), and symptomatic cerebral embolizations are common (12-35%). The 1-year mortality reported after SAB and SAE is 19-62% and reflects deaths from underlying diseases and complications caused by the infection. In a subset of SAE cases, valvular heart surgery is needed (15-45%), but active intravenous drug use seems to be a reason to refrain from surgery. Despite its importance, there are insufficient data on the optimal management of SAB and SAE, especially on the required duration of antibiotic therapy.  Conclusions: The epidemiology of SAB and SAE has been changing in the past decades. They still carry a substantial morbidity and mortality. Intensified studies on treatment are warranted for improving patient outcome.

The Changing Epidemiology of Infective Endocarditis in the Twenty-First Century

PURPOSE OF THE REVIEW

Infective endocarditis (IE) is a relatively infrequent infectious disease. It does, however, causes serious morbidity, and its mortality rate has remained unchanged at approximately 25%. Changes in IE risk factors have deeply impacted its epidemiology during recent decades but literature from low-income countries is very scarce. Moreover, prophylaxis guidelines have recently changed and the impact on IE incidence is still unknown.

RECENT FINDINGS

In high-income countries, the proportion of IE related to prior rheumatic disease has decreased significantly and has been replaced proportionally by cases related to degenerative valvulopathies, prosthetic valves, and cardiovascular implantable electronic devices. Nosocomial and non-nosocomial-acquired cases have risen, as has the proportion caused by staphylococci, and the median age of patients. In low-income countries, in contrast, rheumatic disease remains the main risk factor, and streptococci the most frequent causative agents. Studies performed to evaluate impact of guidelines changes' have shown contradictory results. The increased complexity of cases in high-income countries has led to the creation of IE teams, involving several specialties. New imaging and microbiological techniques may increase sensitivity for diagnosis and detection of IE cases. In low-income countries, IE remained related to classic risk factors. The consequences of prophylaxis guidelines changes are still undetermined.

Antibiotic Resistance of Non-pneumococcal Streptococci and Its Clinical Impact

The taxonomy of streptococci has undergone major changes during the last two decades. The present classification is based on both phenotypic and genotypic data. Phylogenetic classification of streptococci is based on 16S rRNA sequences [1], and it forms the backbone of the overall classification system of streptococci. Phenotypic properties are also important, especially for clinical microbiologists. The type of hemolysis on blood agar, reaction with Lancefield grouping antisera, resistance to optochin, and bile solubility remain important for grouping of clinical Streptococcus isolates and therefore treatment options [2]. In the following chapter, two phenotypic classification groups, viridans group streptococci (VGS) and beta-hemolytic streptococci, will be discussed.

Low mortality but increasing incidence of Staphylococcus aureus endocarditis in people who inject drugs: Experience from a Swedish referral hospital

Staphylococcus aureus is a leading cause of infective endocarditis in people who inject drugs (PWID). The management of S aureus endocarditis (SAE) in PWID can be problematic. The objective of this retrospective observational study was to assess the epidemiology, clinical characteristics, and mortality of S aureus endocarditis (SAE) in PWID in Stockholm, Sweden.The Department of Infectious Diseases at the Karolinska University Hospital serves as a regional referral center for drug users with severe infections. Patients with active intravenous drug use treated for SAE at the department between January 2004 and December 2013 were retrospectively identified. Clinical and microbiological data were obtained from medical records and the diagnosis verified according to the modified Duke criteria.In total, 120 SAE episodes related to intravenous drug use were identified. Its incidence in Stockholm was 0.76/100,000 adult person-years for the entire period, increasing from 0.52/100,000 person-years in 2004 to 2008 to 0.99 in 2009 to 2013 (P = 0.02). The SAE incidence among PWID specifically was 249 (range 153-649) /100,000 person-years. Forty-two (35%) episodes were left-sided, and multiple valves were involved in 26 (22%). Cardiac valve surgery was performed in 10 (8%) episodes, all left-sided. The in-hospital and 1-year mortality rates were 2.5% (3 deaths) and 8.0% (9 deaths), respectively.We noted a high and increasing incidence over time of SAE related to intravenous drug use in Stockholm. The increased incidence partly reflects a rising number of PWID during the study period. The low mortality noted, despite a substantial proportion with left-sided endocarditis, probably in part reflects the quality of care obtained at a large and specialized referral center for drug users with severe infections.

The increasing incidence of infective endocarditis in Denmark, 1994-2011

BACKGROUND

Little updated population-based evidence exists of temporal trends in infective endocarditis (IE).

METHODS

For the 1994-2011 period, we used Danish nationwide registries to identify cases with first-time IE and to estimate the population size. We calculated the incidence rate of IE in 3-year intervals. To evaluate time trends in incidence, we used the 1994-1996 period as reference and computed incidence ratios and 95% confidence intervals (CI) as the incidence in each of the subsequent 3-year intervals divided by the incidence in the reference period.

RESULTS

We identified 5486 incident IE patients (65% men) and the mean age at diagnosis was 63years. Men tended to be younger at diagnosis than women; 62years vs. 65years. Mean age at IE diagnosis steadily increased from 57years in 1994-1996 to 65years in 2009-2011. The IE incidence rate increased from 3.93 per 100,000 person-years in 1994-1996 to 7.55 per 100,000 person-years in 2009-2011, corresponding to an incidence ratio of 1.92 (95% CI: 1.74-2.12). The increase in incidence over time was more pronounced in men (2.28, 95% CI: 2.02-2.59) than in women (1.39, 95% CI: 1.18-1.64). We observed no increase in incidence over time for subjects younger than 50years, whereas the incidence increased substantially over time for elderly patients, with the highest incidence ratio of 3.38 (95% CI: 2.55-4.52) for patients more than 80years at IE onset.

CONCLUSION

The incidence of IE increased over time particularly among men and for the older age groups.

Endocarditis as a Marker for New Epidemics of Injection Drug Use

BACKGROUND

We examined discharges for infective endocarditis (IE) at an academic teaching hospital for over 10 years to evaluate if an increase in hospitalizations for IE and increase in hepatitis C virus (HCV) in patients with IE could predict a new epidemic of injection drug use (IDU).

MATERIALS AND METHODS

Retrospective medical record review of discharged patients with the diagnosis of IE as defined by the modified Duke criteria. Student's t test, chi-squared test and Fisher's exact test were used to calculate P values.

RESULTS

There were 542 discharges among 392 unique patients with IE and 104 patients were readmitted 2-7 times. Of the total discharges, 367 (67.7%) were not screened for HCV, and of those tested, 86 (49.1%) were HCV+; 404 (74.5%) were not screened for HIV and of those tested, 28 (20.3%) were HIV+. Patients who self-identify as a person who injects drugs were more likely to be tested for HCV, 75 (69.4%) versus 12 (31.5%, P < 0.0001), and for HIV, 72 (66.6%) versus 13 (34.2%, P < 0.0001) compared with those who self-report no IDU. Those with a positive result for opiate or heroin toxicology test were more likely to be screened for HCV, 70 (66%) versus 22 (44.8%, P < 0.0001), and for HIV, 66 (62.2%) versus 25 (51%, P < 0.0001) than those with negative result for toxicology test. Over this period, there was a 2-fold increase in IE cases, a 3-fold increase in HCV antibody prevalence and a 6-fold increase in opiate toxicology screens showing positive result, but no increase in HIV.

CONCLUSIONS

Although IDU is a known risk factor for IE, the observation of a sharp increase in IE cases may signal a new epidemic of IDU and HCV.

Surgical outcomes of infective endocarditis among intravenous drug users

BACKGROUND

With increasing prevalence of injected drug use in the United States, a growing number of intravenous drug users (IVDUs) are at risk for infective endocarditis (IE) that may require surgical intervention; however, few data exist about clinical outcomes of these individuals.

METHODS

We evaluated consecutive adult patients undergoing surgery for active IE between 2002 and 2014 pooled from 2 prospective institutional databases. Death and valve-related events, including reinfection or heart valve reoperation, thromboembolism, and anticoagulation-related hemorrhage were evaluated.

RESULTS

Of the 436 patients identified, 78 (17.9%) were current IVDUs. The proportion of IVDUs increased from 14.8% in 2002 to 2004 to 26.1% in 2012 to 2014. IVDUs were younger (aged 35.9 ± 9.9 years vs 59.3 ± 14.1 years) and had fewer cardiovascular risk factors than non-IVDUs. During follow-up (median, 29.4 months; quartile 1-3, 4.7-72.6 months), adverse events among all patients included death in 92, reinfection in 42, valve-reoperation in 35, thromboembolism in 17, and hemorrhage in 16. Operative mortality was lower among IVDUs (odds ratio, 0.25; 95% confidence interval [CI], 0.06-0.71), but overall mortality was not significantly different (hazard ratio [HR], 0.78; 95% CI, 0.44-1.37). When baseline profiles were adjusted by propensity score, IVDUs had higher risk of valve-related complications (HR, 3.82; 95% CI, 1.95-7.49; P < .001) principally attributable to higher rates of reinfection (HR, 6.20; 95% CI, 2.56-15.00; P < .001).

CONCLUSIONS

The proportion of IVDUs among surgically treated IE patients is increasing. Although IVDUs have lower operative risk, long-term outcomes are compromised by reinfection.

Incidence and Predictors of Infective Endocarditis in Mitral Valve Prolapse: A Population-Based Study

OBJECTIVE

To determine the incidence and predictors of infective endocarditis (IE) in a population-based cohort of patients with mitral valve prolapse (MVP).

PATIENTS AND METHODS

We identified all adult Olmsted County residents with MVP diagnosed by echocardiography from January 1989 to December 1998 and cross-matched them with the Rochester Epidemiology Project-identified Olmsted County cases of IE from January 1, 1986, through December 31, 2006. We retrospectively analyzed and de novo confirmed each IE case using the modified Duke criteria.

RESULTS

There were 896 Olmsted County residents with echocardiographically diagnosed MVP (mean age, 53±21 years; 565 women [63%]). The mean follow-up period was 11±5 years. The 15-year cohort risk of IE after MVP diagnosis was 1.1%±0.4% (incidence, 86.6 cases per 100,000 person-years; 95% CI, 43.3-173.2 cases per 100,000 person-years); thus, the age- and sex-adjusted relative risk of IE in patients with MVP was 8.1 (95% CI, 3.6-18.0) in comparison to the general population of Olmsted County (P<.001). There were no IE cases in patients without previously diagnosed mitral regurgitation (MR). Conversely, IE incidence was higher in patients with MVP with moderate, moderate-severe, or severe MR (289.5 cases per 100,000 person-years; 95% CI, 108.7-771.2 cases per 100,000 person-years; P=.02 compared with trivial, mild, or mild-moderate MR) and in patients with a flail mitral leaflet (715.5 cases per 100,000 person-years; 95% CI, 178.9-2861.0 cases per 100,000 person-years; P=.02 compared with no flail mitral leaflet).

CONCLUSION

The population-based incidence of IE in adults with MVP is higher than those previously reported in case-control, tertiary care center studies. Patients with MVP and moderate, moderate-severe, or severe MR or a flail mitral leaflet are at a notable risk of developing IE in comparison with those without MR.

Clinical manifestations of infective endocarditis in relation to infectious agents: An 8-year retrospective study

AIM

To compare clinical complications and outcomes of infective endocarditis (IE) episodes caused by Staphylococcus aureus (S. aureus) and other most frequent aetiological agents (streptococci, enterococci, coagulase-negative staphylococci, and culture-negative IE).

METHODS

A total of 117 IE episodes assessed by all internal medicine services of a major teaching institution in the Czech Republic over an eight-year period were identified.

RESULTS

We found that S. aureus IE episodes (n = 36) were significantly more associated with systemic embolism (41.7% vs 18.5%, P = 0.01), severe sepsis/septic shock (33.3% vs 3.7%, P < 0.0001), and in-hospital mortality (33% vs 12.3%, P = 0.01). No differences in local, structural, and/or functional complications (cardiac abscess formation, impaired integrity of the valvular apparatus, conduction disturbances, or incidence of heart failure) were observed between studied groups. Long-term survival estimates were significantly improved in patients with IE caused by agents other than S. aureus (13.78 median years vs 5.48 median years, P=0.03).

CONCLUSIONS

IE episodes caused by S. aureus are associated with both increased short-term and long-term mortality. Of all the studied parameters, only systemic embolism and severe sepsis/septic shock predicted in-hospital mortality.

Infective endocarditis in the military patient

Infective endocarditis (IE) is a potentially fatal cardiac infection associated with an inhospital mortality rate of up to 22%. Fifty per cent of IE cases develop in patients with no known history of valve disease. It is therefore important to remain vigilant to the possibility of the diagnosis in patients with a febrile illness and unknown source. From a military perspective, our patients are unique due to the breadth of pathogens they are exposed to, and blood-culture-negative IE is a risk. In particular, there should be awareness of Coxiella burnetii as a possible causative pathogen. In this review we incorporate the latest consensus from systematic reviews and publications identified by a literature search through Medline. We describe the diagnosis and management of IE with particular reference to the military population.

Global and regional burden of infective endocarditis, 1990-2010: a systematic review of the literature

Infective endocarditis (IE) is a life-threatening disease associated with serious complications. The GBD 2010 (Global Burden of Disease, Injuries, and Risk Factors) study IE expert group conducted a systematic review of IE epidemiology literature to inform estimates of the burden on IE in 21 world regions in 1990 and 2010. The disease model of IE for the GBD 2010 study included IE death and 2 sequelae: stroke and valve surgery. Several medical and science databases were searched for IE epidemiology studies in GBD high-, low-, and middle-income regions published between 1980 and 2008. The epidemiologic parameters of interest were IE incidence, proportions of IE patients who developed stroke or underwent valve surgery, and case fatality. Literature searches yielded 1,975 unique papers, of which 115 published in 10 languages were included in the systematic review. Eligible studies were population-based (17%), multicenter hospital-based (11%), and single-center hospital-based studies (71%). Population-based studies were reported from only 6 world regions. Data were missing or sparse in many low- and middle-income regions. The crude incidence of IE ranged between 1.5 and 11.6 cases per 100,000 people and was reported from 10 countries. The overall mean proportion of IE patients that developed stroke was 0.158 ± 0.091, and the mean proportion of patients that underwent valve surgery was 0.324 ± 0.188. The mean case fatality risk was 0.211 ± 0.104. A systematic review for the GBD 2010 study provided IE epidemiology estimates for many world regions, but highlighted the lack of information about IE in low- and middle-income regions. More complete knowledge of the global burden of IE will require improved IE surveillance in all world regions.

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.

[Aortic infective endocarditis: Value of surgery. About 48 cases]

INTRODUCTION

Infective endocarditis (IE) is a serious disease whose prognosis depends on early management. Aortic location is characterized by its evolution toward myocardial failure and the high number of complications reasons for early surgery.

AIM

To compare the short- and mid-terms results of surgery for aortic infective endocarditis (IE) in the active phase and the healed phase.

PATIENTS AND METHODS

We analyzed retrospectively the data of 48 consecutive patients operated for aortic infective endocarditis between January 2000 and January 2012. The data on operative mortality, morbidity and major cardiovascular events (mortality, recurrent endocarditis, reintervention, and stroke) were analyzed.

RESULTS

Twenty-three patients (48%) underwent surgery during the active phase (group I), 19 on native and 4 on prosthetic valves, and 25 patients (52%) were operated during healed endocarditis (group II) only on native valve. Mean age was 39 years (12-81) with a male predominance (83%). Rheumatic valvular disease was the main etiology of underlying valvular disease in both groups (85%). The clinical feature was dominated by signs of cardiogenic shock in group I and dyspnea exertion stage III-IV NYHA in group II. Streptococcus and Staphylococcus germs were most frequently encountered. Indication for surgery was heart failure in group I, it was related to the symptoms, the severity of valvular disease and its impact on the left ventricle in group II. An aortic valve replacement with a mechanical prosthesis was performed in the majority of cases (83%). Postoperative mortality concerned only one patient in group I. Twenty-one patients (44%) were followed for a mean of 30 months (1-72). One patient in group II died following cerebral hemorrhagic stroke related to accident with vitamin K antagonist. In both groups, there was an improvement in the functional class. No recurrence of endocarditis was noted in both groups during follow-up.

CONCLUSION

The prognosis of infective endocarditis of the aortic valve is severe due to the fast progression to heart failure. Early medical and surgical approach provides good results on morbidity and mortality in the short- and mid-terms.

Biodegradable materials for surgical management of infective endocarditis: new solution or a dead end street?

Background

One third of patients with infective endocarditis will require operative intervention. Given the superiority of valve repair over valve replacement in many indications other than endocarditis, there has been increasing interest and an increasing number of reports of excellent results of valve repair in acute infective endocarditis. The theoretically ideal material for valve repair in this setting is non-permanent, “vanishing” material, not at risk of seeding or colonization. The goal of this contribution is to review currently available data on biodegradable materials for valve repair in infective endocarditis.

Discussion

Rigorous electronic and manual literature searches were conducted to identify reports of biodegradable materials for valve repair in infective endocarditis. Articles were identified in electronic database searches of Medline, Embase and the Cochrane Library, using a predetermined search strategy. 49 manuscripts were included in the review. Prosthetic materials needed for valve repair can be summarized into annuloplasty rings to remodel the mitral or tricuspid annulus, and patch materials to replace resected valvar tissue. The commercially available biodegradable annuloplasty ring has shown interesting clinical results in a single-center experience; however further data is required for validation and longer follow-up. Unmodified extra-cellular matrix patches, such as small intestinal submucosa, have had promising initial experimental and clinical results in non-infected valve repair, although in valve repair for endocarditis has been reported in only one patient, and concerns have been raised regarding their mechanical stability in an infected field.

Summary

These evolving biodegradable devices offer the potential for valve repair with degradable materials replaced with autologous tissue, which could further improve the results of valve repair for infective endocarditis. This is an evolving field with promising experimental or initial clinical results, however long-term outcomes are lacking and further data is necessary to validate this theoretically interesting approach to infective endocarditis.

Epidemiology of infective endocarditis in a large Belgian non-referral hospital

OBJECTIVES

Guidelines for diagnosis of infective endocarditis are largely based upon epidemiological studies in referral hospitals. Referral bias, however, might impair the validity of guidelines in non-referral hospitals. Recent studies in non-referral care centres on infective endocarditis are sparse. We conducted a retrospective epidemiological study on infective endocarditis in a large non-referral hospital in a Belgian city (Kortrijk).

METHODS

The medical record system was searched for all cases tagged with a putative diagnosis of infective endocarditis in the period 2003-2010. The cases that fulfilled the modified Duke criteria for probable or definite infective endocarditis were included.

RESULTS

Compared to referral centres, an older population with infective endocarditis, and fewer predisposing cardiac factors and catheter-related infective endocarditis is seen in our population. Our patients have fewer prosthetic valve endocarditis as well as fewer staphylococcal endocarditis. Our patients undergo less surgery, although mortality rate seems to be highly comparable with referral centres, with nosocomial infective endocarditis as an independent predictor of mortality.

CONCLUSION

The present study suggests that characteristics of infective endocarditis as well as associative factors might differ among non-referral hospitals and referral hospitals.

Infective endocarditis: prevention, diagnosis, and management

Infective endocarditis (IE) is among the most severe infectious disease, the prevention of which has not decreased its incidence. The age of patients and the rate of health care-associated IE have increased as a consequence of medical progress. The prevention strategies have been subjected to an important debate and nonspecific hygiene measures are now placed above the use of antibiotic prophylaxis. Indeed, the level of evidence of antibiotic prophylaxis efficiency is low and the indications of its prescription have been restricted in the recent international guidelines. In cases carrying a high suspicion of IE, efforts should be made to rapidly identify patients with a definite or highly probable diagnosis of IE and to find the causative pathogen to ensure that appropriate treatment, including urgent valvular surgery, begins promptly. Although echocardiography remains the main accurate imaging modality to identify endocardial lesions associated with IE, it can be negative or inconclusive especially in cases of prosthetic valve or other intracardiac devices. Recent studies demonstrated the diagnostic value of other imaging strategies including cardiac computed tomography (CT), positron emission tomography/CT, radiolabelled leukocyte single-photon emission CT/CT, and cerebral magnetic resonance imaging. Novel perspectives on the management of endocarditis are emerging and offer a hope for decreasing the rate of residual deaths by accelerating the processes of diagnosis, risk stratification, and instauration of antimicrobial therapy. Moreover, the rapid transfer of high-risk patients to specialized mediosurgical centres (IE team), the development of new surgical modalities, and close long-term follow-up are of crucial importance.

Changing pattern of infective endocarditis in Iran: A 16 years survey

OBJECTIVES

To investigate the changes in characteristics of patients with infective endocarditis in Iran and comparing the results with the changing profiles of Infection Endocarditis (IE) in other countries.

METHODOLOGY

We studied all patients with definite or possible IE seen at four referral teaching hospitals in Iran from Jan. 1995 to Dec. 2010. The data was analyzed both collectively and separately in two consecutive eight-year periods, i.e. 1995-2003 and 2004-2010.

RESULTS

A total of 286 episodes of IE, 172 males and 114 females, were reviewed from which 162 ones were in the first eight-year time period and 124 episodes in the second one. Mean age of the patients was significantly increased in the second eight-year period (24.2±11 vs 39.4±15 years old, p value = 0.01). Increase in the episodes caused by Staphylococcus aureus was significant (40.7% vs 22.8%, p value = 0.01). The mean size of the vegetation was noticeably higher among IDUs than non-IDUs (1.53±0.1cm vs 0.76±0.2cm, p value < 0.001). As well as extra cardiac complications, mortality rate was noticeably higher among the patients with vegetation size ≥ 1cm (34.4% vs 16.3%, p value = 0.003). There was not a significant difference regarding the mortality rate between the conservatively and surgically treated patients (20.7% vs 22.9%, p value = 0.07).

CONCLUSION

The most important changing characteristic of IE which influences the outcome of the disease seems to be vegetation size which can account for as the outcome predictor.

Infective endocarditis epidemiology over five decades: a systematic review

AIMS

To Assess changes in infective endocarditis (IE) epidemiology over the last 5 decades.

METHODS AND RESULTS

We searched the published literature using PubMed, MEDLINE, and EMBASE from inception until December 2011.

DATA FROM

Einstein Medical Center, Philadelphia, PA were also included. Criteria for inclusion in this systematic review included studies with reported IE microbiology, IE definition, description of population studied, and time frame. Two authors independently extracted data and assessed manuscript quality. One hundred sixty studies (27,083 patients) met inclusion criteria. Among hospital-based studies (n=142; 23,606 patients) staphylococcal IE percentage increased over time, with coagulase-negative staphylococcus (CNS) increasing over each of the last 5 decades (p<0.001) and Staphylococcus aureus (SA) in the last decade (21% to 30%; p<0.05). Streptococcus viridans (SV) and culture negative (CN) IE frequency decreased over time (p<0.001), while enterococcal IE increased in the last decade (p<0.01). Patient age and male predominance increased over time as well. In subgroup analysis, SA frequency increased in North America, but not the rest of the world. This was due, in part, to an increase in intravenous drug abuse IE in North America (p<0.001). Among population-based studies (n=18; 3,477 patients) no significant changes were found.

CONCLUSION

Important changes occurred in IE epidemiology over the last half-century, especially in the last decade. Staphylococcal and enterococcal IE percentage increased while SV and CN IE decreased. Moreover, mean age at diagnosis increased together with male:female ratio. These changes should be considered at the time of decision-making in treatment of and prophylaxis for IE.

Management of patients with infective endocarditis by a multidisciplinary team approach: an operative protocol

Even in the modern era of advanced diagnostic imaging, improved antibiotic therapy and potentially curative surgery, infective endocarditis remains a serious disease with high rates of morbidity and mortality. Reasons for such a persistently poor outcome may be represented by the changing epidemiology and microbiology, with new groups of patients at risk and new and more aggressive microorganisms. However, the inadequate use of both diagnostic (blood cultures and echocardiography) and therapeutic (antibiotics and surgery) means can influence the generally delayed diagnosis and poor prognosis seen in patients with infective endocarditis. We tried to identify the critical points in the management of patients with infective endocarditis and to elaborate a formal multidisciplinary approach based on the strict collaboration of specialists in infectious diseases, microbiology, cardiology and cardiac surgery. We hypothesized that this approach could increase the adherence to the published guidelines, and could represent a means to improve the outcome of patients with infective endocarditis.

A nationwide cohort study of mortality risk and long-term prognosis in infective endocarditis in Sweden

OBJECTIVES

Infective endocarditis (IE) remains a serious disease with substantial mortality. In this study we investigated the incidence of IE, as well as its associated short and long term mortality rates.

METHODS

The IE cases were identified in the Swedish national inpatient register using ICD-10 codes, and then linked to the population register in order to identify deaths in the cohort. Crude mortality rates among IE patients were obtained for different time intervals. These rates were directly standardized using sex- and age-matched mortality in the general population.

RESULTS

The cohort consisted of 7603 individuals and 7817 episodes of IE during 1997-2007. The 30 days all-cause crude mortality rate was 10.4% and the standardized mortality ratio (SMR) was 33.7 (95% confidence interval [CI]: 31.0-36.6). Excluding the first year of follow-up, the long term mortality (1-5 years) showed an increased SMR of 2.2 (95% CI: 2.0-2.3) compared to the general population. Significantly higher SMR was found for cases of IE younger than 65 years of age with a 1-5 year SMR of 6.3, and intravenous drug-users with a SMR of 19.1. Native valve IE cases, in which surgery was performed had lower crude mortality rates and Mantel-Haenzel odds ratios of less than one compared to those with medical therapy alone during 30-day and 5-years follow-up.

CONCLUSIONS

The 30-days crude mortality rate for IE was 10.4% and long-term relative mortality risk remains increased even up to 5 years of follow-up, therefore a close monitoring of these patients would be of value.

The risk for bacterial endocarditis in cirrhotic patients: a population-based 3-year follow-up study

BACKGROUND

We noted only rare reports of cirrhotic patients with bacterial endocarditis (BE). There is insufficient data on the risk of BE in liver cirrhosis. This is the first national population-based study evaluating the risk of BE in cirrhotic patients.

METHODS

We used the National Health Insurance Database, which is derived from the Taiwan National Health Insurance Program. The study cohort comprised 40803 patients with cirrhosis and the comparison cohort consisted of 40841 randomly selected subjects with a similar age and sex distribution.

RESULTS

Of the total 81644 patients, 192 (0.24%) experienced BE during the 3-year follow-up period, 121 patients from the study cohort (0.30% of the cirrhotic patients) and 71 patients from the comparison group (0.17% of non-cirrhotic patients) (p<0.001). After adjusting for patient age, sex, and comorbid disorders, the Cox regression analysis showed that cirrhotic patients had a high risk of BE compared to non-cirrhotic patients during the 3-year follow-up period (hazard ratio 2.04, 95% confidence interval 1.61-2.44, p<0.001).

CONCLUSION

We conclude that liver cirrhosis is a risk factor for the occurrence of BE.

Evaluating treatment options for patients with infective endocarditis: when is it the right time for surgery?

Infective endocarditis remains a life-threatening condition with an unchanging incidence and mortality of nearly 30% at 1 year. Surgery is required in 25–50% of acute infections and 20–40% of patients during convalescence. Operative procedures are often technically challenging and high-risk, often due to coexistent multisystem disease. However, international guidelines provide clear indications for surgical intervention, which are applicable for the majority of patients. These are not, however, supported by particularly robust clinical evidence and decision-making often needs to be tailored to the advancing age of the overall patient cohort, the presence of multisystem disease, comorbidities, prior antibiotic therapy of varying duration and the availability of surgical expertise. Native valve endocarditis will be the initial focus of this article, along with subgroups including prosthetic valve endocarditis. We present the treatment options for patients with infective endocarditis, evaluate the evidence-base that supports current clinical practice and attempt to provide an insight and subsequent recommendations for the timing of surgery.

NDV-3, a recombinant alum-adjuvanted vaccine for Candida and Staphylococcus aureus, is safe and immunogenic in healthy adults

The investigational vaccine, NDV-3, contains the N-terminal portion of the Candida albicans agglutinin-like sequence 3 protein (Als3p) formulated with an aluminum hydroxide adjuvant in phosphate-buffered saline. Preclinical studies demonstrated that the Als3p vaccine antigen protects mice from oropharyngeal, vaginal and intravenous challenge with C. albicans and other selected species of Candida as well as both intravenous challenge and skin and soft tissue infection with Staphylococcus aureus. The objectives of this first-in-human Phase I clinical trial were to evaluate the safety, tolerability and immunogenicity of NDV-3 at two different antigen levels compared to a saline placebo. Forty healthy, adult subjects were randomized to receive one dose of NDV-3 containing either 30 or 300 μg of Als3p, or placebo. NDV-3 at both dose levels was safe and generally well-tolerated. Anti-Als3p total IgG and IgA1 levels for both doses reached peak levels by day 14 post vaccination, with 100% seroconversion of all vaccinated subjects. On average, NDV-3 stimulated peripheral blood mononuclear cell (PBMC) production of both IFN-γ and IL-17A, which peaked at day 7 for subjects receiving the 300 μg dose and at day 28 for those receiving the 30 μg dose. Six months after receiving the first dose of NDV-3, nineteen subjects received a second dose of NDV-3 identical to their first dose to evaluate memory B- and T-cell immune responses. The second dose resulted in a significant boost of IgG and IgA1 titers in >70% of subjects, with the biggest impact in those receiving the 30 μg dose. A memory T-cell response was also noted for IFN-γ in almost all subjects and for IL-17A in the majority of subjects. These data support the continued investigation of NDV-3 as a vaccine candidate against Candida and S. aureus infections.