Relation of level of B-type natriuretic peptide with outcomes in patients with infective endocarditis

Elevated B-type natriuretic peptide (BNP) is a marker of poor outcomes in heart failure, acute coronary syndromes, and sepsis. Elevated cardiac troponin I (cTnI) is associated with adverse outcomes in infective endocarditis. It was hypothesized that elevated BNP would be associated with increased rates of morbidity and mortality in patients with infective endocarditis, particularly when combined with elevated cTnI. Consecutively enrolled patients in the International Collaboration on Endocarditis Prospective Cohort Study (ICE-PCS) were evaluated at a single center. The association between elevated BNP and a composite outcome of death, intracardiac abscess, and central nervous system event and the individual components of the composite was determined. Similar analyses were performed in patients who had BNP and cTnI measured. Of 103 patients, 45 had BNP measured for clinical indications. The median BNP level was higher in patients with the composite outcome (1,498 vs 433 pg/ml, p = 0.03) and in those who died (2,150 vs 628 pg/ml, p = 0.04). Elevated BNP was significantly associated with the composite outcome (p <0.01) and intracardiac abscess (p = 0.02). Patients with elevation of BNP and cTnI had a significantly higher probability of the composite outcome (69%) than patients with either BNP or cTnI elevated (29%) or neither BNP nor troponin elevated (0%) (p for trend <0.01). In conclusion, these data demonstrate a significant association between elevated BNP alone and in combination with cTnI for serious outcomes in infective endocarditis and warrant prospective evaluation.

[Hybrisep, a new method for the diagnosis of blood culture-negative infective endocarditis: a case report]

Blood cultures were considered as the gold standard for the diagnosis of infective endocarditis (IE) but were frequently negative. This report describes an IE patient who successfully underwent aortic valve replacement; it discusses a new diagnostic method of blood culture-negative IE. Recently, Hybrisep (FUSO Pharmaceutical Industries, Japan), a rapid diagnostic method for bacteremia was developed using in situ hybridization, which is superior in sensitivity to conventional blood cultures. In this case, echocardiography confirmed severe aortic regurgitation and aortic valve vegetations, while serial blood cultures could not reveal any pathogenic organisms. A preoperative serum sample was found to be positive for Enterococcus faecalis by Hybrisep. Gram stain examination of the excised valves showed gram-positive cocci and therefore correlated with the finding by Hybrisep. After surgery, the patient was successfully treated with appropriate antibiotics according to these results. In summary, Hybrisep will have a promising positive impact on IE patient care.

Nonbacterial thrombotic endocarditis complicated with stage Ia ovarian cancer

Nonbacterial thrombotic endocarditis (NBTE) commonly occurs in advanced malignancies associated with a cancer-related hypercoagulable state, but the prevalence of NBTE in patients with less advanced malignancies is unknown. A 46-year-old woman had multiple thromboembolic events and disseminated intravascular coagulation on admission. Transthoracic echocardiography showed several growths on the mitral valve. Pelvic magnetic resonance imaging revealed a rapidly enlarging large tumor. In spite of anticoagulation therapy, she died 1.5 months after admission. At autopsy, NBTE with stage Ia ovarian cancer was diagnosed. In cases of higher-growth rate tumors with abundant necrosis, NBTE may occur in early-stage (even in stage Ia) ovarian cancer. In the majority of stage Ia ovarian cancers, curative surgical resection can be done. Prognostic improvement may be gained by such positive intervention, although this depends on the patient's general condition when NBTE occurs. With tumor resection, there is a possibility that the patient will recover from the hypercoagulable state and a poor outcome will be avoided.

[Morphological changes in blood plasma of patients with infectious endocarditis]

The aim of the study was to examine the morphological picture of sera obtained from 34 patients with infectious endocarditis (IE) pre-, intra- and postoperatively after their cuneiform dehydration. The method allowed integral homeostasis to be assessed including detection of markers of various pathological processes (onset of generalization of Candida infection and development of polyorgan dysfunction). Results of surgical treatment of IE for the period of 2002-2007 are presented.

[Prognostic useful of the new risk index for infective endocarditis]

The aim of study was the separation of the group of patients with the high risk of death based on the risk index (I(R)) calculated with use of C-reactive protein and hemoglobin concentrations measured on the admission.

MATERIAL AND METHODS

The initial group consisted 41 patients (16 women and 25 men) hospitalized between 1999 and 2005 with the recognition of the infective endocarditis based on the Duke University criteria. The IR was calculated according to the formula: I(R) = [(CRP[mg/l])/(Hgb[g/dl]-beta)] x 10, and the coefficient beta = 6 g/dl.

RESULTS

The I(R) was significantly higher among deceased patients than among patients with good early prognosis (376,6 vs 79,9; p < 0,001). The risk index exceeding 100 is strongly associated with high death risk among patients with infective endocarditis.

CONCLUSION

This index may also be very useful in reaching the diagnosis and the efficacy prognosing of treatment.

Clinical significance of high-density lipoprotein cholesterol in left-sided infective endocarditis

Decreased serum levels of high-density lipoprotein (HDL) cholesterol have been shown to be of prognostic significance in patients with severe infectious diseases. Serum HDL cholesterol levels were therefore investigated as a possible parameter for the prediction of clinical outcomes in patients with left-sided infective endocarditis (IE). Fifty-four patients with IE with available admission serum HDL cholesterol levels were included in the study. A clinical outcome was defined as a complicated course during hospitalization. Forty-two patients had complicated courses during their in-hospital stays. The median serum HDL cholesterol level was significantly lower in patients with IE (n = 54) than healthy controls (n = 26) (26 vs 47 mg/dl, p <0.0001). In the 42 patients with complicated courses, the median serum HDL cholesterol level was lower compared with that in 12 patients with uneventful courses (24 vs 36 mg/dl, p = 0.011). A cut point of serum HDL cholesterol level of 25 mg/dl had sensitivity of 62%, specificity of 75%, and a positive predictive value of 90% for predicting clinical outcomes. In conclusion, serum HDL cholesterol levels measured at admission were markedly reduced in patients with left-sided IE. Furthermore, low serum HDL cholesterol levels predicted complicated clinical courses in these patients.

[The significance of investigation of the endothelium function in diagnosis and assessment of effectiveness of treatment of infective endocarditis]

The complex state of the endothelium function was studied in 25 patients with infective endocarditis in the preoperative and early terms after surgery. A reliable elevation of all indices of endothelium dysfunction independent of the localization of the formed heart disease was detected. Against the background of operative treatment reliable changes demonstrating an improved functional state of the endothelium were noted in the early postoperative period.

[Pseudoinfectious endocarditis in antiphospholipid syndrome]

The antiphospholipid syndrome (APhS) is autoimmune non-inflammatory trombotic vasculopathy, associated with damage of vessels of any caliber and localization that determines the diversity of clinical manifestations of this syndrome. One of possible localizations of thrombosis in AphS is pseudoinfective endocarditis (PsIE). We have performed analysis of clinical and laboratory features of APhS, associated with PsIE. 28 APhS patients with PsIE, average age--44+/-13 years, were included in the study. Among them 21 patients had primary form of APhS, 7 cases had secondary form of APhS. For statistical treatment of the results the logistic regression (SPSS for Windows. Release 11.5.0.) was used, the confidence level of differences between groups was determined with the use of Student's test. Heart valve abnormalities occurred in 100% of patients and included valvular thickening, induration and sclerosis, the presence of valve vegetations, focip of calcinosis and different grade of valve dysfunction. Mitral and aortal valve vegetations occurred with the same incidence (64%), both valves were been involved in 29% of cases. Positive associations with presence/development of PsIE in APhS from multivariant model data included mitral valve lesion (OR: 0.029), focal cardiofibrosis (OR: 0.084), prior valve lesion (OR: 0.087), negative associations--hemicrania (OR: 8.627) and secondary form of APhS (OR: 6.425). Moderately high titer of lupous anticoagulant (multivariant model) (OR: 3.753) seemed to be prognostic marker of PsIE. In half of patients with APhS and PsIE systemic embolisms appeared, embolic cerebrovascular complications were the most frequent (32%). The possibility of development of hemodynamically significant valve dysfunction that needs valve replacement and nececcity of making of differential diagnosis with infective endocarditis are related to other aspects, important for clinical practice.

Endocarditis por Aspergillus fumigatus en válvula nativa con hemocultivo positivo y galactomanano negativo. Descripción de un caso y revisión de la literatura

Native valve endocarditis caused by Aspergillus spp. is an uncommon disease with a high mortality rate. Generally, Aspergillus is isolated from affected valve in post-mortem or biopsy specimens. However, its isolation from blood cultures is exceedingly rare. We report a case of fungal endocarditis in a native mitral valve with the isolation of Aspergillus fumigatus both in valve vegetation and in blood culture bottles. The patient underwent valve replacement and antifungal treatment with voriconazole and caspofungin, but he died on post-operative day 45 with disseminated aspergillosis confirmed by necropsy. Paradoxically, galactomannan antigen detection in serum was negative. This is the third case of Aspergillus endocarditis with positive blood culture reported in the literature.

Plasma antioxidant capacity in dogs with naturally occurring heart diseases

The aim of the study was to compare the plasma levels of antioxidants by measuring total antioxidant activity (TAS) and ferric reducing ability of the plasma (FRAP) in healthy dogs and in those that are suffering from dilated cardiomyopathy (DCM) or from mitral endocardiosis (ME). Dogs with echocardiographically diagnosed ME (10 dogs) as well as DCM (23 dogs) were sampled. Of dogs with DCM, eight having DCM with sinus rhythm (SR) were included in the DCM-SR group and 15 having DCM with atrial fibrillation (AF) in the DCM-AF group. Total antioxidant levels measured by TAS assay differed neither significantly between the cardiac patients and the control group nor between the heart disease groups. Ferric reducing ability of the plasma in animals with cardiac disease was significantly higher than in the control animals, and the difference was also significant in between the two DCM groups. However, the differences between the antioxidant levels of the DCM and ME groups did not reach significance in none of the antioxidant (TAS and FRAP) tests. Summarizing the results of this study it can be concluded that there is an increased antioxidant reactivity detected by the FRAP, but not by the TAS assay in the blood of dogs with naturally occurring cardiac disorders. The magnitude of this increase seems to be more affected rather by the severity of the cardiac insufficiency and/or by the heart rate or rhythm disorder than by the underlying heart disease itself.

Epidemiology of infective endocarditis in Tunisia: a 10-year multicenter retrospective study

BACKGROUND

Since the first description of infective endocarditis, the profile of the disease has evolved continuously with stable incidence. However, epidemiological features are different in developing countries compared with western countries.

OBJECTIVE

To describe epidemiological, microbiological and outcome characteristics of infective endocarditis in Tunisia.

PATIENTS AND METHODS

This was a descriptive multicenter retrospective study of inpatients treated for infective endocarditis from 1991 to 2000. Charts of patients with possible or definite infective endocarditis according to the Duke criteria were included in the study.

RESULTS

Four hundred and forty episodes of infective endocarditis among 435 patients (242 males, 193 females; mean (SD) age=32.4 (16.8) years, range 1-78 years) were reviewed. The most common predisposing heart disease was rheumatic valvular disease (45.2%). Infective endocarditis occurred on prosthetic valves in 17.3% of cases. Causative microorganisms were identified in 50.2% of cases: streptococci (17.3%), enterococci (3.9%), staphylococci (17.9%), and other pathogens (11.1%). Blood cultures were negative in 53.6% and no microorganism was identified in 49.8%. Early valve surgery was performed in 51.2% of patients. The in-hospital mortality was 20.6%.

CONCLUSION

Infective endocarditis is still frequently associated with rheumatic disease among young adults in Tunisia, with a high frequency of negative blood cultures and high in-hospital mortality, given that the population affected is relatively young.

[Blood culture negative endocarditis: a diagnostic challenge]

Blood culture negative endocarditis (BCNE) account for about 5% of all cases of endocarditis. Diagnosis and initiation of antimicrobial therapy may be delayed, with a negative impact on clinical outcome. The most common cause of BCNE is antimicrobial drug therapy before blood sampling. Other common causes include slow growing and non cultivable organisms. Identification of the etiologic agent is critical in the management of BCNE and molecular tools such as broad range 16SrRNA PCR technique followed by direct automated sequencing and microorganism-specific PCR are promising. Some authors have proposed to include these techniques among major Duke's criteria for the diagnosis of BCNE.

[Infectious endocarditis with negative blood cultures]

Blood culture is a key investigation for the diagnosis of infectious endocarditis (IE). When negative, there are diagnostic and therapeutic problems. The aim of this study was to determine the frequency, the clinical features and the aetiological factors of IE with negative blood cultures compared with IE with positive blood cultures compared with IE with positive blood cultures. The authors undertook a retrospective review of 98 cases of patients admitted for IE from 1991 to 2000 to the Department of Infectious Diseases and Cardiology of Sousse (Tunisia). Of the 98 patients, 48 (48.9%), 29 men and 19 women with an average age of 34.3 years, had negative blood cultures. An infectious agent was identified in 7 cases (14.5%) by serology, valve culture or cerebrospinal fluid including Brucella (2), Coxiella (1) and Candida (1). Therefore, in 41 cases (42%), the cause of IE was not determined. Transthoracic echocardiography was of diagnostic value in 96% of cases and transoesophageal echocardiography showed disease not observed on transthoracic echocardiography in 5 cases. The main complication was cardiac failure (27 cases). The mortality was 14.5%. Comparison of the two groups showed that negative blood cultures were associated with a higher incidence of previous antibiotic therapy, extracardiac signs of IE and cardiac failure. Early surgical indications and mortality were the same in both groups. This report confirmed the high frequency of IE with negative blood cultures. Previous antibiotic therapy seems to be an important aetiological factor but cannot explain this high frequency. Methodological problems of blood cultures and the absence of systematic investigation for rare infectious agents are other possible factors.

[Attempt of estimation of Q fever endocarditis frequency in Poland]

Up to now no Q fever endocarditis (caused by rickettsia Coxiella burnetii) has been diagnosed in Poland. Potential endocarditis caused by Coxiella burnetii strains can be related to a group of strains present in Poland or sensitivity of Polish Population. The aim of the study was to estimate frequency of Q fever endocarditis is patients of National Institute of Cardiology and to characterize Coxiella burnetii strains and correlation between frequency of Q fever endocarditis and the group of strains. In all patients infective endocarditis and valvular heart disease were diagnosed. In all cases vegetations on TTE or TEE and negative blood cultures were confirmed. No fungal antigens or elevated anti-Candida and anti-Aspergillus antibodies were found. Serological investigations as far as it concerns C. burnetii antibodies were negative in all cases. No Coxiella burnetii infection were found in patients with infective endocarditis and negative blood cultures in the National Institute of Cardiology. However due to high probability of occurrence of such an infection in Poland further investigations in other centers would be useful.

Increased levels of soluble adhesion molecules, E-selectin and P-selectin, in patients with infective endocarditis and embolic events

AIMS

Inflammation-induced procoagulant changes and endothelial cell activation appear to play an important role in thromboembolic complications of infective endocarditis. Hence, the aim of this study was to compare the plasma levels of soluble adhesion molecules E- and P-selectin in infective endocarditis patients with and without embolic events, and healthy subjects.

METHODS AND RESULTS

The study group consisted of 76 consecutive patients (mean age=26 years old, range from 8 to 64 years) with definite infective endocarditis according to the Duke criteria. Thirteen of the patients (17.1%) had embolic events. Transoesophageal echocardiographic examinations were performed on all patients within 3 days of initiation of antimicrobial therapy. Although there was a trend towards a higher rate of vegetations detected in those with embolic events than in those without, this did not reach statistical significance (84.6% vs 80.9%, P>0.05). Significantly larger vegetations were observed in patients with embolic events as compared to those without embolic events (1.4 cm vs 1.0 cm, P=0.03). The mean plasma concentrations of P-selectin were elevated in patients with embolic events as compared to both patients without embolic events and control subjects (58.69+/-7.49 ng x ml(-1)vs 29.65+/-5.69 ng x ml(-1), P=<0.001 and 58.69+/- 7.49 ng x ml(-1) vs 25.82+/-5.38 ng x ml(-1), P<0.001). Similarly, the patients with embolic events had increased plasma levels of E-selectin compared to those without embolic events and the control group (73.15+/-11.47 ng x ml(-1) vs 42.84+/-8.77 ng x ml(-1), P<0.001 and 73.15+/- 11.47 ng x ml(-1) vs 34.23+/-5.92 ng x ml(-1), P<0.001).

CONCLUSION

Determination of these membrane activation molecules may provide useful markers with which to identify patients at high thromboembolic risk from infective endocarditis.

Sulbactam efficacy in experimental models caused by susceptible and intermediate Acinetobacter baumannii strains

Sulbactam and imipenem were compared in an experimental pneumonia model in immunocompetent mice, using a susceptible strain of Acinetobacter baumannii, and in an experimental endocarditis model in rabbits, using an intermediately susceptible strain. In the former, sulbactam was as efficacious as imipenem in terms of survival, sterility of lungs and in the bacterial clearance from lungs and blood, provided that the t > MIC for sulbactam (1.84 h) was similar to that for imipenem (2.01 h). In the endocarditis model, imipenem (t > MIC, 2.12 h) was more efficacious than sulbactam (t > MIC, 1.17 h) in bacterial clearance from vegetations. These results show the efficacy of sulbactam in infections caused by susceptible strains of A. baumannii, with an MIC up to 4 mg/L, provided that doses reach a t > MIC similar to that of imipenem. The activity of sulbactam was time dependent.

Antiendothelial antibodies in sera of patients with infective endocarditis

Infective endocarditis is characterized by the colonization of endocardium by microorganisms. Except for Staphylococcus aureus, microorganisms are not able to adhere to and grow on endocardial cells; prior damage, e.g., by shear stress or other mechanical factors, is necessary. But other causes may well have a share. This study was, therefore, designed to identify immunological factors, especially antibodies against endothelial cells, which could contribute to the initiation of endocardial injury. Sera of patients with infective endocarditis and healthy controls were investigated for the presence of antibodies against endothelial antigen. As the antigen source human umbilical vein endothelial cells were used. Antibodies against endothelial cells were detected by indirect immunofluorescence, ELISA, immunoblotting, antibody dependent cellular cytotoxicity, and antibody mediated cytotoxicity. Antibodies against endothelial cells were found in seven out of fifteen patients. These antibodies were directed against cytoplasmic structures and only appeared in the course of the disease. A correlation between the presence of these antibodies and disease activity or the outcome of disease was not observed. These antibodies may develop as a consequence of damage to endocardial cells (thereby exposing intracellular antigen to the immune system) and do not seem to play a role in the pathogenesis of infective endocarditis.

Adhesion molecules (E-selectin, intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1)) in sera from patients with Staphylococcus aureus bacteraemia with or without endocarditis

The aim of this prospective study was to evaluate if patients with endocarditis display a more extensive endothelial activation than those with bacteraemia but without endocarditis. Sixty-five patients with blood culture-verified Staphylococcus aureus bacteraemia were included and serum samples collected on admission were analysed by enzyme immunoassays. Elevated serum concentrations of adhesion molecules were found in most of the patients with S. aureus bacteraemia. Patients with endocarditis (n = 15) showed significantly higher serum E-selectin (median 156 ng/ml) and VCAM-1 (median 1745 ng/ml) concentrations compared with those with S. aureus bacteraemia but without endocarditis (80 ng/ml and 1172 ng/ml, respectively; P = 0.01 and P = 0.003). No significant difference was found between the groups concerning ICAM-1 (median 451 ng/ml versus 522 ng/ml). In addition, serum tumour necrosis factor-alpha (TNF-alpha) concentrations were significantly correlated (P < 0.002) to serum levels of E-selectin, ICAM-1 and VCAM-1.

[The level of erythropoietin in serum of patients with anemia during infective endocarditis]

The infective endocarditis is a septic syndrome caused by an infection in endocardium or in heart valves. The majority of patients with infective endocarditis develop normocytic anemia. The metabolic studies in septic shock syndromes documented an intensive proteolysis of muscles, visceral organs and blood proteins, and probably of erythropoietin as a glycoprotein as well. The aim of the study was to assess the erythropoietin level in patients with infective endocarditis severe anemia and preserved renal function. Erythropoietin concentration was measured in blood serum in 12 patients (11 men and 1 woman), mean age 48 +/- 8 years, with infective endocarditis. The patients had clinical symptoms of endocarditis, positive blood bacteriological cultures and echocardiography features. All patients had serious normocytic anemia with mean hemoglobin concentration 5.40 +/- 0.48 mmol/L. The control group consisted of 7 healthy persons (5 men and 2 women), mean age 50 +/- 7 years, with hemoglobin concentration 8.70 +/- 0.60 mmol/L. The concentration of erythropoietin at the patients with bacterial endocarditis was 144.04 +/- 17.80 mIU/mL versus 67.28 +/- 6.29 mIU/mL in the control group (p = 0.0002). We conclude that in patients with infective endocarditis and serious normocytic anemia without renal insufficiency the concentration of erythropoietin is increased.

Moraxella catarrhalis endocarditis: report of a case and literature review

A 53-year-old man developed severe acute systemic illness three weeks after an upper respiratory tract infection. Serial blood cultures grew Moraxella catarrhalis. During antibiotic treatment, fever and infectious parameters disappeared, but severe aortic regurgitation developed. Aortic valve replacement was performed, during which extensive destruction of the aortic valve was noted. Endocarditis due to M. catarrhalis is very rare with, to our knowledge, only six cases having been reported to date. M. catarrhalis is a normal commensal of the upper respiratory tract, but in unpredictable circumstances can become an important pathogen. Bacteremia due to this organism therefore requires prompt treatment, as serious organ complications, including endocarditis, can occur.