Determinants of prognosis in 300 episodes of infective endocarditis

Clinical Profile and Outcome of Patients with Cardiac Implantable Electronic Device-Related Infection

Fundamento

Houve aumento expressivo na incidência de infecções relacionadas a dispositivos cardíacos eletrônicos implantáveis (DCEI) nos últimos anos, com impacto na mortalidade.

Objetivos

Verificar a proporção de pacientes com infecção de DCEI e analisar seu perfil clínico, as variáveis relacionadas com a infecção e sua evolução.

Método

Estudo retrospectivo, observacional e longitudinal com 123 pacientes com infecção de DCEI entre 6.406 procedimentos. Foram usados os testes paramétricos, e o nível de significância adotado na análise estatística foi de 5%.

Resultados

A idade média dos pacientes foi de 60,1 anos, e 71 eram homens. A média de internação foi de 35,3 dias, e houve remoção total do sistema em 105 pacientes. Identificaram-se endocardite infecciosa (EI) e sepse em 71 e 23 pacientes, respectivamente. A mortalidade intra-hospitalar foi 19,5%. Houve associação entre EI e extrusão do gerador (17,0% vs. 19,5% nos grupos com e sem EI, respectivamente, p = 0,04; associação inversa) e sepse (15,4% vs. 3,2%, p = 0,01). Houve associação entre morte intra-hospitalar e EI (83,3% vs. 52,0% com e sem morte, respectivamente, p = 0,005) e sepse (62,5% vs. 8,1%, p < 0,0001). Foi dada alta hospitalar a 99 pacientes. Durante a média de seguimento clínico de 43,8 meses, a taxa de mortalidade foi de 43%, e 65,2% dos pacientes com sepse faleceram (p < 0,0001). A curva de sobrevida de Kaplan-Meier não indicou associação significante com sexo, agente etiológico, fração de ejeção, EI e modalidade de tratamento. A taxa de mortalidade foi de 32,8% entre os pacientes submetidos a reimplante de eletrodos por via endocárdica e 52,2% entre aqueles por via epicárdica (p = 0,04). Não houve influência da etiologia chagásica, a qual correspondeu a 44,7% das cardiopatias de base, quanto às variáveis clínicas e laboratoriais ou à evolução.

Conclusões

A taxa de infecção foi de 1,9%, com predomínio em homens. Houve associação entre mortalidade intra-hospitalar e EI e sepse. Após a alta hospitalar, a taxa de mortalidade anual foi de 11,8%, com influência de sepse durante a internação e o implante epicárdico. (Arq Bras Cardiol. 2021; [online].ahead print, PP.0-0)

Iranian Registry of Infective Endocarditis (IRIE): Time to relook at the guideline, regarding to regional differences

Aims

Infective endocarditis (IE) remained a potentially fatal disease with high rate of mortality and morbidity. The epidemiology and global burden of IE are largely different between the countries. We aimed to address the epidemiological aspects of IE in a tertiary hospital in Tehran, Iran.

Methods and Results

Between 2006–2018, all adults patients with diagnosis of IE were enrolled in the Iranian Registry of Infective Endocarditis (IRIE). The data were analyzed using the χ², Kolmogorov–Smirnov, and Mann–Whitney U tests. Overall, 602 patients, 407 (67.6%) men, mean age 46 ± 16 years were recruited. Positive blood culture found in 49%.The most common underlying heart diseases were: Congenital heart diseases (CHD) particularly bicuspid aortic valves (BAV) and ventricular septal defects (VSD) in 37%, followed by degenerative heart diseases :flail and mitral valve prolapse (16.3%), intravenous drug user in 12.6%, prosthetic valves in 11.1%, previous IE (8.9%), rheumatic heart diseases (RHD) in 8.4%. The most causative microorganisms were Staphylococcus aureus, Enterococci, coagulase-negative staphylococci and Streptococcus viridans. Cardiac or extra cardiac complications occurred in 56.6% of the patients.

Conclusions

Based on IRIE, IE occurs in the younger population in Iran with high rates of blood culture-negative IE. RHD are not the main cause of IE in Iran, CHD including BAV and VSDs, followed by prolaptic or flail mitral valve were the most common. These 2 groups can be considered a high-risk group for IE. More than half of the patients with IE had cardiac or extra cardiac complications.

Baseline C-reactive protein levels and prognosis in patients with infective endocarditis: A prospective cohort study

Background

Early diagnosis and risk-stratification among infective endocarditis (IE) patients are limited by poor microbiological yield and inadequate characterization of vegetations. A simple tool that can predict adverse outcomes in the early phase of management is required.

Aim

To study the prognostic value of C-reactive protein (CRP) levels at admission and its role in predicting various clinical outcomes.

Methods

In a prospective study of consecutive IE patients diagnosed by modified Duke’s criteria, we measured the peak levels of CRP and erythrocyte sedimentation rate (ESR) in the first 3 days of admission and correlated it with in-hospital mortality, six-month mortality, embolic phenomena and the need for urgent surgery. Predefined laboratory-microbiological sampling protocols and antibiotic-initiation protocols were followed. Receiver-operating-characteristics curves were generated to identify a reliable cut-off for CRP in predicting various outcomes.

Results

Out of 101 patients who were treated, 85 patients had ‘definite’ IE. Blood cultures were positive in 55% (n = 39); and Staphylococcus species was the most common organism. Major complications occurred in 74.1% (n = 63) and in-hospital mortality was 32.9% (n = 28). Mean ESR and CRP levels were 102 ± 31 mm/h and 51 ± 20 mg/l, respectively. In multivariable analysis, high CRP levels were independently predictive of mortality, major complications, embolic events and need for urgent surgery. A CRP >40 mg/l predicted adverse outcomes with a sensitivity of 73% and specificity of 99%.

Conclusion

The study shows that baseline CRP level in the first 3 days of admission is a strong predictor of short term adverse outcomes in IE patients, and a useful marker for early risk stratification.

Infective endocarditis

Infective endocarditis is a serious disease of the endocardium of the heart and cardiac valves, caused by a variety of infectious agents, ranging from streptococci to rickettsia. The proportion of cases associated with rheumatic valvulopathy and dental surgery has decreased in recent years, while endocarditis associated with intravenous drug abuse, prosthetic valves, degenerative valve disease, implanted cardiac devices, and iatrogenic or nosocomial infections has emerged. Endocarditis causes constitutional, cardiac and multiorgan symptoms and signs. The central nervous system can be affected in the form of meningitis, cerebritis, encephalopathy, seizures, brain abscess, ischemic embolic stroke, mycotic aneurysm, and subarachnoid or intracerebral hemorrhage. Stroke in endocarditis is an ominous prognostic sign. Treatment of endocarditis includes prolonged appropriate antimicrobial therapy and in selected cases, cardiac surgery. In ischemic stroke associated with infective endocarditis there is no indication to start antithrombotic drugs. In previously anticoagulated patients with an ischemic stroke, oral anticoagulants should be replaced by unfractionated heparin, while in intracranial hemorrhage, all anticoagulation should be interrupted. The majority of unruptured mycotic aneurysms can be treated by antibiotics, but for ruptured aneurysms, endovascular or neurosurgical therapy is indicated.

Mild renal dysfunction on admission is an important prognostic predictor in patients with infective endocarditis: a retrospective single-center study

OBJECTIVE

Infective endocarditis (IE) continues to be associated with high mortality. The aim of the present study was to identify prognostic predictors for short-term mortality in patients with IE.

METHODS

We conducted a retrospective study of 119 consecutive patients with IE (mean age 58±17). Prognostic predictors for mortality at the early phase of admission were determined using a multivariate regression analysis, and a receiver operating characteristic (ROC) analysis was carried out to evaluate the predictive ability.

RESULTS

Eleven of 119 patients died during hospital admission. In this non-survivor group, the clinical parameters at the time of admission, including serum creatinine (Cr), the estimated glomerular filtration rate (eGFR), the red blood cell count, the white blood cell count, the serum CRP level and heart rate, differed significantly from those observed in the survivors (all; p<0.05). According to a logistic regression analysis, an increase in log-serum Cr per one standard deviation (odds ratio=2.18, 95%CI=1.08-4.41) and a decrease in log-eGFR per one standard deviation (odds ratio=0.51, 95%CI=0.26-0.98) were significantly associated with in-hospital death. The area under the ROC curve for serum Cr to predict the outcome was 0.80, the sensitivity was 64% and the specificity was 85% at a cut-off value of 1.16 mg/dL. For eGFR, the area under the ROC curve was 0.77, the sensitivity was 64% and the specificity was 86% at a cut-off value of 47.5 mL/min./1.73 m(2).

CONCLUSION

Mild renal dysfunction at the time of admission is an important predictor of early phase mortality in patients with IE.

Contemporary epidemiology and prognosis of septic shock in infective endocarditis

AIMS

The prognosis of patients with infective endocarditis (IE) remains poor despite the great advances in the last decades. One of the factors closely related to mortality is the development of septic shock (SS). The aim of our study was to describe the profile of patients with IE complicated with SS, and to identify prognostic factors of new-onset SS during hospitalization.

METHODS AND RESULTS

We conducted a prospective study including 894 episodes of IE diagnosed at three tertiary centres. A backward logistic regression analysis was undertaken to determine prognostic factors associated with SS development. Multivariable analysis identified the following as predictive of SS development: diabetes mellitus [odds ratio (OR) 2.06; confidence interval (CI) 1.16-3.68], Staphylococcus aureus infection (OR: 2.97; CI: 1.72-5.15), acute renal insufficiency (OR: 3.22; CI: 1.28-8.07), supraventricular tachycardia (OR: 3.29; CI: 1.14-9.44), vegetation size ≥15 mm (OR: 1.21; CI: 0.65-2.25), and signs of persistent infection (OR: 9.8; CI: 5.48-17.52). Risk of SS development could be stratified when combining the first five variables: one variable present: 3.8% (CI: 2-7%); two variables present: 6.3% (CI: 3.2-12.1%); three variables present: 14.6% (CI: 6.8-27.6%); four variables present: 29.1% (CI: 11.7-56.1%); and five variables present: 45.4% (95% CI: 17.5-76.6%). When adding signs of persistent infection, the risk dramatically increased, reaching 85.7% (95% CI: 61.2-95.9%) of risk.

CONCLUSIONS

In patients with IE, the presence of diabetes, acute renal insufficiency, Staphylococcus aureus infection, supraventricular tachycardia, vegetation size ≥15 mm, and signs of persistent infection are associated with the development of SS.

Surgical management and mid-term outcomes of 108 patients with infective endocarditis

This study evaluates the early and mid-term outcomes, predictors of mortality and morbidity and quality of life of patients operated for infective endocarditis. Data on 108 patients undergoing 113 surgical procedures during October 1998 to January 2010 was prospectively collected. NYHA Class was >III in 49 (43.4%) cases. Thirty-seven (33%) patients had isolated mitral valve procedures, 58 (51%) had aortic valve, two had tricuspid valve and 16 had multivalvular procedures. Active endocarditis was noted in 86 (76%) procedures, native valve endocarditis in 105 (93%) and prosthetic valve endocarditis in eight procedures. Logistic EuroSCORE at presentation was >14 in 18 (17%) patients. Staphylococcus aureus was the most common organism isolated. Follow-up was carried out in 76/85 (88.37%) of surviving patients, and the mean follow-up time was 37.2 months. Functional class and quality of life (using EQ-5D Health Questionnaire) were assessed by telephone interviews. NYHA Class on follow-up was I-II in 62/76 (83%). Multivariate predictor of 30-day mortality was peripheral vascular disease (p = 0.025) whilst multivariate predictors of long-term survival were male sex (p = 0.01), peripheral vascular disease (p = 0.02) and bypass time (p = 0.006). The overall survival was 87% at one year and 80% at five years. Thirty-three percent (25/76) patients reported a score reflecting full health. Optimal antibiotic therapy and timely surgical intervention were associated with improved functional class, quality of life and mid-term survival.

In-hospital prognosis of prosthetic valve endocarditis after urgent surgery

INTRODUCTION AND OBJECTIVES

Prosthetic valve endocarditis is associated with high morbidity and mortality, particularly when urgent surgery is needed. The identification of factors that predict a poor prognosis is the first step in improving outcomes. The study objectives were to characterize patients with prosthetic valve endocarditis who need urgent surgery and to identify factors that predict in-hospital mortality in this high-risk group.

METHODS

From a database of 648 consecutive patients with infective endocarditis diagnosed between 1996 and 2006 at four tertiary-care centers with cardiac surgery facilities, 46 patients with left-sided prosthetic valve endocarditis who needed urgent surgery were identified. A retrospective study was carried out to determine these patients' main characteristics and to identify predictors of in-hospital mortality.

RESULTS

The main indications for urgent surgery were heart failure (57%) and persistent infection (33%). In-hospital mortality was 41%. Factors significantly associated with a poor prognosis were fever at admission, persistent infection, positive blood cultures, persistently positive cultures, and echocardiographic evidence of vegetations (P< .05). No specific microorganism was associated with a poor prognosis.

CONCLUSIONS

Prosthetic valve endocarditis was associated with high mortality when urgent surgery was needed. Although heart failure was the principle reason for urgent surgery, it did not lead to a worse in-hospital prognosis. The presence of vegetations and uncontrolled infection were the main factors associated with higher in-hospital mortality in patients with left-sided infective endocarditis who needed urgent surgery.

In-hospital mortality of infective endocarditis: prognostic factors and evolution over an 8-year period

Infective endocarditis (IE) remains severe. Few predictors of prognosis have been identified. It is not known whether mortality of IE has decreased during recent decades. 559 definite cases of IE were collected in a prospective population-based survey in 1999 in France. In-hospital death rate was 17%. It was lower in operated patients (14.4% vs 19.3%), although not significantly so. In multivariate analysis, the following variables were independent and significant predictors of mortality: history of heart failure (odds ratio: 2.65), history of immunosuppression (OR: 3.34), insulin-requiring diabetes mellitus (OR: 7.82), left-sided IE (OR: 1.97), heart failure (OR: 2.19), septic shock (OR: 4.33), lower Glasgow coma scale score (OR: 4.09), cerebral haemorrhage (OR: 9.46), and higher C-reactive protein level (OR: 2.60). Adjusted mortality was significantly lower in 1999 than in 1991 (22%): OR: 0.64 (p = 0.03). Thus, in a large and unselected cohort of patients hospitalized for IE in 1999, in-hospital mortality rate was lower than in 1991. Multivariate analysis identified factors classically known as having an impact on mortality. However, other factors, such as age and responsibility of Staphylococcus aureus, were not retained in the model.

Prognostic stratification of patients with left-sided endocarditis determined at admission

BACKGROUND

The prognosis of patients with left-sided endocarditis remains poor despite the progress of surgical techniques. Identification of high-risk patients within the first days after admission to the hospital would permit a more aggressive therapeutic approach.

METHODS

We designed a prospective multicenter study to find out the clinical, microbiologic, and echocardiographic characteristics available within 72 hours of admission that might define the profile of high-risk patients. Of 444 episodes, 317 left-sided endocarditis cases were included and 76 variables were assessed. Events were surgery in the active phase of the disease and in-hospital death. A stepwise logistic regression analysis was undertaken to determine variables predictive of events.

RESULTS

Multivariate analysis of the clinical variables found to have statistical significance in the univariate analysis identified the following as predictive: patient referred from another hospital (odds ratio [OR]: 1.8; confidence interval [CI], 1.1-2.9), atrioventricular block (OR: 2.5; CI, 1.1-5.9), acute onset (OR: 1.7; CI, 1.1-2.9), and heart failure at admission (OR: 2.3; CI, 1.4-3.8). When the echocardiographic and microbiological variables statistically significant in the univariate analysis were introduced, the presence of heart failure at admission (OR: 2.9; CI, 1.8-4.8), periannular complications (OR: 1.8; CI, 1.1-3.1), and Staphylococcus aureus infection (OR: 2.0; CI, 1.1-3.8) retained prognostic power. Risk could be accurately stratified when combining the 3 variables with predictive power: 0 variables present: 25% of risk; 1 variable present: 38% to 49% of risk; 2 variables present: 56% to 66% of risk; and 3 variables present: 79% of risk.

CONCLUSIONS

The risk of patients with left-sided endocarditis can be accurately stratified with the assessment of variables easily available within 72 hours of admission to the hospital.

Clinical features and predictors for mortality in patients with infective endocarditis at a university hospital in Taiwan from 1995 to 2003

The clinical features and microbiological characteristics of 315 patients with definite or possible infective endocarditis (IE) from January 1995 to December 2003 were evaluated. There were 187 males and 128 females with a mean age of 51 years (range, 1 month to 92 years). Ninety-three patients (30%) had a diagnosis of valvular heart disease and 24 (8%) had received prosthetic valve replacement. Blood culture was negative in 62 patients (20%). Staphylococci (91 patients, 32%), including methicillin-susceptible Staphylococcus aureus (15%), methicillin-resistant S. aureus (11%), and coagulase-negative staphylococci (6%), were the most commonly encountered pathogens followed by viridans group streptococci (77 patients, 24%). Eight patients (25%) had various neurological, renal, embolic, and cardiac complications. Patients with neurological complications [odds ratio (OR) 8.175, P<0.001], nosocomial IE (OR 6.661, P<0.001), underlying malignancy (OR 4.993, P<0.001), elevated serum creatinine level (OR 3.132, P=0.001), or elevated WBC count (>15000/mm3) (OR 2.537, P=0.007) were at significantly increased risk of mortality. This study found mortality from IE was associated with several factors, among which neurological complications were the most hazardous. Patients with more than one risk factor had poorer prognosis. These results suggest the need for more aggressive management in patients with IE when multiple risk factors for mortality are identified.

Clinicopathologic findings and outcome in dogs with infective endocarditis: 71 cases (1992–2005)

OBJECTIVES

To evaluate clinical, laboratory, and necropsy findings in dogs with infective endocarditis (IE).

DESIGN

Retrospective case series.

ANIMALS

71 dogs with possible or definite IE.

PROCEDURES

Medical records were reviewed for signalment, clinical features, and results of clinicopathologic testing and diagnostic imaging. Yearly incidence and the effect of variables on survival were determined by use of survival curve analysis.

RESULTS

The overall incidence of IE was 0.05%. Most affected dogs were of large breeds, and > 75% were older than 5 years. The aortic valve was affected in 36 of the 71 (51%) dogs, and the mitral valve was affected in 59%. Lameness caused by immune-mediated polyarthritis, septic arthritis, or peripheral arterial thromboembolism was observed in 53% of the dogs. Neurologic complications were diagnosed in 17 of 71 (24%) dogs. Thromboembolic disease was suspected in 31 of 71 (44%) of dogs. The mortality rate associated with IE was 56%, and median survival time was 54 days. Factors negatively associated with survival included thrombocytopenia, high serum creatinine concentration, renal complications, and thromboembolic complications.

CONCLUSIONS AND CLINICAL RELEVANCE

A diagnosis of IE should be suspected in dogs with fever, systolic or diastolic murmur, and locomotor problems. Dogs with thrombocytopenia, high serum creatinine concentration, thromboembolism, or renal complications may have a shorter survival time.

Clinical features remain important for the diagnosis of infective endocarditis in the modern era

BACKGROUND

Infective endocarditis (IE) can be difficult to diagnose, due to multiple (often non-specific) presenting features.

AIM

To assess the predictive accuracy of classical clinical features and blood investigations readily available at the time of presentation.

DESIGN

Cross-sectional analysis.

METHODS

We studied 29 IE cases and 79 controls (clinically suspicious contemporaneous cases where IE was subsequently excluded) from a hospital-based group of patients referred to a cardiac department with possible infective endocarditis. Patients were identified from the echocardiography database. Cases were defined by final diagnosis. Symptoms, signs, risk factors for IE and blood investigations were recorded from case notes and examined by univariate and multivariate analyses.

RESULTS

The sensitivity, specificity, and positive and negative predictive values of transthoracic echocardiography (TTE) for detection of IE in clinically suspected cases were 71%, 98%, 57% and 99%, respectively. Univariate analyses revealed a significant association between IE and several clinical features. Under multivariate analysis, previous heart valve surgery (OR 13.3, 90%CI 3.2-55.6), positive blood cultures (OR 17.2, 90%CI 4.9-58.8), signs of embolism (OR 11.4, 90%CI 3.0-43.5), a new, altered or changing murmur (OR 10.3, 90%CI 2.8-38.5) and splenomegaly (OR 18.2, 90%CI 3.6-90.9) were independent predictors for IE.

DISCUSSION

Clinical features at presentation continue to be important for the diagnosis of IE. Features such as positive blood cultures, signs of embolism and a changing heart murmur should be used to guide investigation and treatment of IE prior to echocardiography, or when TTE is negative.

Influence of diabetes mellitus on the clinical manifestations and prognosis of infective endocarditis: a report from the International Collaboration on Endocarditis-Merged Database

The purpose of this investigation was to study the influence of diabetes mellitus (DM) on outcomes of infective endocarditis (IE). Outcomes were compared between 150 diabetic and 905 non-diabetic patients with IE from the International Collaboration on Endocarditis Merged Database. Compared to non-diabetic patients, diabetic patients were older (median age 63 vs 57 y, p<0.001), were more often female (42.0% vs 31.9%, p=0.01), more often had comorbidities (41.5% vs 26.7%, p<0.001), and were more likely to be dialysis dependent (12.7% vs 4.0%, p<0.001). S. aureus was isolated more often (30.7% vs 21.7%, p=0.02), and microorganisms from the viridans Streptococcus group less often (16.7% vs 28.2%, p = 0.001) in the diabetic group. There was no difference with respect to the presence of congestive heart failure, embolism, intra-cardiac abscess, new valvular regurgitation, or valvular vegetation. Diabetic patients underwent surgical intervention less frequently (32.0% vs 44.9%, p = 0.003), and had higher overall in-hospital mortality (30.3% vs 18.6%, p = 0.001). On multivariable analysis, DM was an independent predictor of mortality (odds ratio (OR) = 1.71, 95% confidence interval (CI) 1.08-2.70), especially in male patients, as diabetic males had higher mortality than non-diabetic males (OR 2.18, CI 1.08-4.35). DM is an independent predictor of in-hospital mortality among patients hospitalized with IE.

Mortality from infective endocarditis: clinical predictors of outcome

OBJECTIVE

To identify clinical markers available within the first 48 hours of admission that are associated with poor outcome in infective endocarditis.

DESIGNS

Retrospective cohort study.

SETTING

Teaching hospital.

PATIENTS

208 of 220 patients with infective endocarditis.

METHODS

Consecutive patients with infective endocarditis presenting between 1981 and 1999 to a tertiary centre were studied. Clinical, echocardiographic, and haematological data recorded within 48 hours of admission were obtained. Data were analysed using logistic regression models.

MAIN OUTCOMES MEASURES

Mortality at discharge and at six months.

RESULTS

Data were obtained for 93% of patients who were eligible for inclusion. 194 (93%) were positive for Duke criteria. Mean age was 52 (1.2) years, and 138 (66%) were men. 82 (39%) were transferred from other hospitals. 181 (87%) were blood culture positive, and 47 (23%) infections were Staphylococcus aureus. The infection was located on aortic (n = 85, 41%), mitral (n = 77, 37%), tricuspid (n = 18, 9%), and multiple valves (n = 20, 10%). 67 (32%) had prosthetic valve endocarditis. 48% of the cohort were managed with antibiotics alone. Mortality at discharge was 18% and at six months 27%. Duration of illness before admission, age, sex, valve infected, infecting organism, and left ventricular function were not predictors of adverse mortality. However, abnormal white cell count, serum albumin concentration, serum creatinine concentration, or cardiac rhythm, the presence of two major Duke criteria, or visible vegetation conferred a poor prognosis.

CONCLUSIONS

Conventional prognostic factors in this study did not appear to predict outcome early during hospital admission. However, simple clinical indices, which are readily available, are reliable, cheap, and potentially powerful predictors of poor outcome.

Staphylococcus aureus, Platelets, and the Heart

Infective endocarditis (IE) caused by Staphylococcus aureus is serious, burgeoning frequency, and growing increasingly resistant to antibiotics. S. aureus IE is associated with high morbidity and mortality rates in nosocomial and community-acquired settings. S. aureus is the most common, most virulent IE etiologic pathogen. S. aureus IE pathogenesis depends upon complex interaction among the pathogen, platelets, plasma proteins, and vascular endothelial cells. S. aureus coordinates the expression of key virulence factors required for the specific pathogenic phases of IE. Platelets, now appear to play an important role in antimicrobial host defense against S. aureus IE and other endovascular infections. Platelet microbicidal proteins are believed to significantly contribute to the antimicrobial properties of platelets; however, abnormal disposition of native or prosthetic cardiac valves is an important risk factor in S. aureus IE establishment and severity. Thus, the need to define the molecular mechanisms of S. aureus pathogenesis and host defense against IE is urgent. Understanding these mechanisms will yield new approaches for the prevention and treatment of such life-threatening cardiovascular infections due to S. aureus.

Infective endocarditis in renal transplant recipients

Because of the increasing number of renal transplantations performed and the rarity of reported cases of infective endocarditis in these patients, we studied the clinical characteristics of this infection in this population. We report on two cases from our experience and review reported cases of infective endocarditis in renal transplant recipients retrieved from the MEDLINE system. In addition, we reviewed a large series of infective endocarditis looking for patients with renal transplants. In addition to our 2 cases, 12 previously reported cases were found. The mean time from transplantation to diagnosis of infective endocarditis was 3.5 years (range 2 months to 15 years). Causative organisms included fungi, Staphylococcus aureus (3 cases each), Corynebacterium sp. (2 cases), Streptococcus viridans, VRE, Brucella sp., Clostridium sp., Nocardia sp. and Erysipelothrix sp. (one case each). Skin manifestations of endocarditis and/or splenomegaly were not reported in these patients. Septic emboli and mycotic aneurysms were relatively common. The overall mortality rate was 50% (7 of 14 patients died). Infective endocarditis seems to be rare in renal transplant recipients. The few reported cases are characterized by unusual causative micro-organisms and atypical clinical presentation. Further studies are needed to delineate the magnitude and scope of this association.

Endocarditis due to Acinetobacter lwoffi on native mitral valve

Endocarditis due to Acinetobacter is a rare pathology with high mortality, reported mainly in hospitalized patients with predisposing risk factors. This is the second case of endocarditis due to Acinetobacter reported in our country in the last 10 years.

The clinical efficacy of continuous-infusion flucloxacillin in serious staphylococcal sepsis

Since the efficacy of beta-lactams against pathogens such as methicillin-susceptible Staphylococcus aureus (MSSA) is related to the time for which serum drug concentrations exceed the MIC for the pathogen, administration of anti-staphylococcal beta-lactams by continuous infusion may provide a more suitable means of drug delivery than intermittent dosing. To assess the clinical efficacy of continuous-infusion therapy, we reviewed the outcomes for 20 consecutive patients with proven serious MSSA sepsis (three with endocarditis, ten osteomyelitis, one endocarditis plus osteomyelitis and six deep abscess) treated with continuous-infusion flucloxacillin (8-12 g/day). Patients initially receiving routine intermittent-dose flucloxacillin therapy were changed to continuous-infusion flucloxacillin (mean duration 29 days; range 4-60 days) for completion of their treatment course. In the majority of cases this was given at home. Serum flucloxacillin concentrations during continuous-infusion flucloxacillin 12 g/day were 11.5->40 mg/L (ten patients) and those during continuous-infusion flucloxacillin 8 g/day were 8->40 mg/L (five patients), these concentrations being well above the expected MIC of flucloxacillin for MSSA. Continuous-infusion flucloxacillin was well tolerated by most patients, and 14/17 patients (82%) who completed their course of continuous-infusion flucloxacillin were judged clinically and microbiologically cured at long-term follow-up (mean 67 weeks; range 4-152 weeks). These preliminary data suggest that, following initial intermittent-dose flucloxacillin therapy, continuous-infusion flucloxacillin is an effective treatment option for serious MSSA sepsis, and forms a feasible and possibly preferable alternative to glycopeptides when considering home-based parenteral therapy for these infections. Further studies are needed to identify whether continuous-infusion flucloxacillin can entirely replace intermittent-dose therapy for such infections.

Cardiac infections: medical and surgical therapies

Infections of the heart can be acute or subacute, depending on host susceptibility, the cause and associated virulence, early diagnosis, and effective therapy. The following review will discuss the causes, clinical manifestations, diagnosis, and medical or surgical management of infective endocarditis, prosthetic valve endocarditis, myocarditis, and pericarditis. Nursing considerations emphasize understanding the pathogenesis, early recognition of signs and symptoms, and appropriate prevention and intervention.