Infective endocarditis due to Atopobium vaginae: a rare association between genital infection and endocarditis of the tricuspid valve

Atopobium vaginae is an anaerobic gram-positive organism associated with genitourinary infections. Bacteraemia is rare, with only two cases reported in the literature. This case describes an 18-year-old type 1 diabetic, presenting with sepsis and haemoptysis, on a background of poor dental hygiene and recurrent hospital admissions. Blood cultures grew A. vaginae and echocardiogram revealed a large tricuspid valve lesion. Despite medical therapy, symptoms of pulmonary emboli continued and she therefore underwent surgical resection of the lesion. Histopathological findings were of a vegetation; culture of the lesion was negative but 16S ribosomal PCR was positive, detecting 16S rRNA of A. vaginae The patient was treated with 4 weeks of vancomycin and made a good recovery. To our knowledge, this represents the first report of infective endocarditis due to this organism. We also provide a review of the literature, including comparing published drug susceptibility data with consensus breakpoints for antimicrobial agents.

Rare cause for a common presentation: isolated pulmonary valve endocarditis yet another mimicker

Isolated pulmonary valve endocarditis (PVE) is a rare condition. Known risk factors in previous case reports were intravenous drug abuse and congenital heart disease. Epidemiology of PVE has been changing. It is now being reported specially following invasive healthcare-related procedures even in patients with structurally normal heart. Vast majority of patients present with respiratory symptoms and diagnosis of endocarditis may be challenging unless there is high index of suspicion. Various microorganisms had been isolated as aetiological agents; however, Enterococcus faecalis is being increasingly isolated. PVE mostly managed conservatively with intravenous antibiotics with option for surgical intervention in specific situations. We present a patient with isolated PVE due to E. faecalis following colonoscopy and polypectomy with predisposing risk factor of alcohol excess, mimicking clinically as pneumonia and radiologically as a neoplastic lesion.

Endocarditis sustained by Streptococcus viridans with normal levels of procalcitonin: an unexpected finding

OBJECTIVE

Procalcytonin is a useful marker of bacterial infections. Several studies have reported elevated serum levels of PCT in patients with infective endocarditis (IE) and/or other infections sustained by cocci. We report a rare case of IE attributed to Streptococcus viridans in whom levels of PCT were normal.

CASE REPORT

A 67 years-old male was admitted to the Emergency Department for a 25-day history of recurring night fever. Upon admission, patient underwent blood test, including PCT, showing normal levels, except for a slight increased creatinine concentration (1.6 mg/dl). CBC showed WBC levels of 10.24 x 10^9/l with neutrophil concentration of 8.64 x 10^9/l. Three blood culture were performed, and all of them were positive for Streptococcus viridans (S. oralis). Dosage of PCT was then repeated two times within the next 2 days after the admission, with negative results. An echocardiogram was performed, showing a lesion of the left anterior aortic leaflet. This finding was confirmed by a transoesophageal echocardiogram. The patient was then treated with G penicillin (6 million of Units quid) for 3 weeks; during the course of antibiotic therapy fever disappeared and blood cultures become negative.

CONCLUSIONS

In the literature, there are just few data about the association between PCT levels and endocarditis and sepsis but there are not etiological differentiations particularly for those sustained by Streptococcus viridans. Only one study suggests that a Streptococcus viridans' infection could reduce PCT accuracy in diagnosis oh endocarditis. So, our observation although come from a single case, could merits, further investigation.

Seroprevalence of Q Fever in Patients Undergoing Heart Valve Replacement Surgery

BACKGROUND AND AIM OF THE STUDY

Q fever, caused by the rickettsia Coxiella burnetii, is a worldwide zoonotic disease with both acute and chronic manifestations. Endocarditis is the principal chronic manifestation. Q fever can easily be mistaken for degenerative valve disease due to its indolent presentation, the fastidious nature of the organism (routine cultures are negative), and the absence of a typical echocardiographic and macroscopic appearance for endocarditis. Prosthetic valve failure, with associated morbidity and mortality, have been described following unrecognized infections.

METHODS

Previous studies have documented the value of screening strategies in areas of high prevalence. Hence, a pilot study was conducted in a low-prevalence setting, in which 139 patients at two tertiary cardiac centers attending for elective valve replacement for degenerative valvular disease underwent testing for chronic Q fever infection by serological and molecular methods on blood and valve tissue.

RESULTS

Five patients (3.7%) had serological evidence of past exposure to Q fever (consistent with rates in the literature). None had evidence of chronic Q fever endocarditis. The cost of adopting a universal screening strategy is around £40,000 per case (if serology is used to screen patients prior to surgery).

CONCLUSIONS

Alternative and more cost-effective methods for identifying clinically quiet cases of chronic Q fever endocarditis are required.

[Infective Endocarditis--Blood Culture and Echocardiography]

Infective endocarditis (IE) is a systemic septic disease that is a microbial infection of the endothelial surface of the heart. Despite advances in medical, surgical, and critical care interventions, IE remains a life-threatening illness. Therefore, it is important to promptly diagnose it using the modified Duke criteria. These criteria integrate factors predisposing patients to the development of IE, the blood-culture isolates and persistence of bacteremia, and echocardiographic findings, along with other clinical and laboratory information. Positive blood culture and a positive echocardiogram are the cornerstones of IE diagnosis. Identification of the infecting organisms is of primary importance because this knowledge guides antibiotic therapy. For the detection of vegetation, transesophageal echocardiography has a sensitivity of 76-100%, whereas that of transthoracic echocardiography ranges from 50 to 60%. Transesophageal echocardiography is particularly useful in patients with prosthetic valves and sparse vegetation. Recent studies reported that causative microorganisms of IE are changing. Staphylococcus aureus is now the most common cause of IE in Western countries. This shift is due in part to a higher rate of Staphylococcus aureus infection in patients with cardiac devices (for example, prosthetic valve, pacemaker, and implantable cardioverter defibrillator [ICD]).

Incremental value of B-type natriuretic peptide for early risk prediction of infective endocarditis

BACKGROUND

Early and accurate risk prediction is an unmet clinical need in patients with infective endocarditis (IE). The aim of this study was to determine the value of B-type natriuretic peptide (BNP) levels obtained on admission for the prediction of in-hospital death in IE patients.

METHODS

Between 2009 and 2011, consecutive patients with IE diagnosed using the revised Duke criteria and admitted to the emergency department were evaluated prospectively. BNP levels were measured on admission. Death during hospitalization was the primary endpoint.

RESULTS

Among 104 consecutive patients with IE and with available BNP levels, 34 (32.7%) died in hospital. BNP levels were significantly higher in patients who died as compared to survivors (709.0 pg/ml vs. 177.5 pg/ml, p<0.001). The accuracy of BNP to predict death as quantified by the area under the receiver operating characteristics curve was 0.826 (95% confidence interval (CI) 0.747-0.905). The value of BNP was additive to that provided by clinical, microbiological, and echocardiography assessment. On multivariate analysis, new heart failure (hazard ratio (HR) 2.02, 95% CI 1.15-3.57, p=0.015), sepsis (HR 2.10, 95% CI 1.25-3.55, p=0.005), Staphylococcus aureus endocarditis (HR 2.67, 95% CI 1.60-4.45, p<0.001), left ventricular ejection fraction ≤55% (HR 1.63, 95% CI 1.00-2.65, p=0.047), and BNP (HR 1.04, 95% CI 1.02-1.06, p<0.001) were independent predictors of in-hospital mortality.

CONCLUSION

Among patients with IE, BNP levels obtained on admission provide incremental value for early and accurate risk prediction.

Latent Q fever endocarditis in patients undergoing routine valve surgery

BACKGROUND AND AIM OF THE STUDY

Q fever is a worldwide zoonosis caused by a fastidious bacterium, Coxiella burnetii. A recent major outbreak of which in the Netherlands will most likely lead to the emergence of hundreds of cases of C. burnetii endocarditis during the next decade. Patients undergoing cardiac valve surgery may carry undiagnosed Q fever endocarditis with possible disastrous outcomes, and hence may benefit from a screening strategy. The study aim was to evaluate the frequency of unsuspected latent Q fever endocarditis in patients undergoing routine valve surgery.

METHODS

At the present authors' institution, all resected cardiac valves/prostheses are examined routinely histologically, microbiologically and on a molecular biological basis, in addition to serological testing for fastidious microorganisms. A retrospective review was conducted of data relating to all patients who had unsuspected Q fever endocarditis that had been diagnosed after routine valve/prosthesis replacement/repair between 2000 and 2013 at the authors' institution.

RESULTS

Among 6,401 patients undergoing valve surgery, postoperative examinations of the explanted valves/prostheses led to an unexpected diagnosis of Q fever endocarditis in 14 cases (0.2%), who subsequently underwent appropriate medical treatments. Only two of the patients (14%) had intraoperative findings suggestive of endocarditis. On serological analysis of the blood samples, 11 patients (79%) presented an evocative Phase I IgG antibody titer > or =800. Valvular tissue-sample analyses yielded positive cultures and PCR in the same 13 patients (93%), whereas pathological and immunohistochemical examinations alone were suggestive of endocarditis in only seven Cases (50%).

CONCLUSION

This screening strategy led to an unexpected diagnosis of Q fever endocarditis in 0.2% of patients undergoing routine valve surgery, who received subsequent appropriate antibiotic therapy. Systematic serological analysis should be mandatory before performing heart valve surgery in countries where C. burnetii is endemic. A positive serology should lead to appropriate valve-specimen analyses, including microbiological, molecular biological and histological evaluations.

Infective endocarditis caused by Enterococcus faecalis treated with continuous infusion of ampicillin without adjunctive aminoglycosides

Aminoglycosides are useful antimicrobial agents for treating infective endocarditis; however, they occasionally cause troublesome side effects, such as nephrotoxicity and ototoxicity. We herein report a case of infective endocarditis caused by Enterococcus faecalis that was treated successfully with continuous infusion of ampicillin without adjunctive aminoglycosides. The serum ampicillin concentrations were higher than the minimal inhibitory concentration for the target strain. Although the use of ampicillin monotherapy is currently avoided because double β-lactam therapy is reportedly more effective, continuous penicillin administration remains an effective therapeutic choice for treating infective endocarditis.

Diagnostic approaches in infective endocarditis

Infective endocarditis is a true systemic infection and a life-threatening disease associated with high mortality.

AIM

To evaluate the problems that occur during making the diagnosis of infective endocarditis, in order to highlight the need of other diagnostic prospects.

MATERIAL AND METHODS

Retrospective study using clinical, microbiological, and echocardiographic findings from 45 patients admitted to the Iasi Infectious Diseases Hospital in the interval January 2007 - January 2011.

RESULTS

A positive diagnosis of infective endocarditis was made based on Duke Criteria. Inflammatory syndrome revealed leukocytosis with neutrophilia in 42% of the patients. In 91% of the cases fever syndrome was present. Blood cultures were positive in almost 45% of the cases, and the identified etiologic agents were Staphylococcus spp., Streptococcus spp., Achromobacter spp., Klebsiella spp., Enterococcus spp., E. coli. In 95% of the patients, the echocardiographic appearance was a major criterion for diagnosis. Associated diseases were most often present with rebound on the course. Cardiac complications occurred despite treatment and re-evaluations. Ten percent of our cases required transfer to cardiology and cardiac surgery units.

CONCLUSIONS

Microbiologic diagnosis was mainly based on cultured-dependent methods that often fail because of previous antibiotic therapy or the involvement of fastidious microorganism. In this case, advances in molecular diagnostics have yielded new tools (polymerase chain reaction - PCR techniques) to diagnose this disease.

Association of troponin T, detected with highly sensitive assay, and outcomes in infective endocarditis

Troponin levels have been correlated with adverse outcomes in multiple disease processes, including congestive heart failure, acute coronary syndromes, sepsis, and, in a few small series, infective endocarditis. We hypothesized that a novel measurement of troponin using a highly sensitive assay would correlate with adverse outcomes when prospectively studied in patients with infective endocarditis. At a single center in the International Collaboration on Endocarditis, 42 patients met the inclusion criteria and underwent testing for cardiac troponin T (cTnT) using both a standard and a highly sensitive precommercial assay. The cTnT levels were associated with the prespecified primary composite outcome of death, central nervous system event, and cardiac abscess. Secondary outcomes included the individual components of the composite outcome and the need for cardiac surgery. A receiver operating characteristic curve was derived and used to identify the optimal cutpoint for cTnT using the highly sensitive assay. cTnT was detectable with the highly sensitive assay in 39 (93%) of 42 patients with infective endocarditis and with the standard assay in 25 (56%) of 42 (p <0.05). Of the 42 patients, 15 experienced the composite outcome, 4 died, 9 had a central nervous system event, and 5 had a cardiac abscess. With the hs-cTnT assay, the median cTnT was greater in the patients who experienced the primary outcome (0.12 vs 0.02 ng/ml, p <0.05). According to the receiver operating characteristic curve analysis (area under the curve of 0.74), cTnT levels of ≥0.08 ng/ml produced optimal specificity (78%) for the primary outcome. The patients with a cTnT level of ≥0.08 ng/ml were more likely to experience the primary outcome (odds ratio 7.0, 95% confidence interval 1.7 to 28.6, p <0.01) and a central nervous system event (odds ratio 9.3, 95% confidence interval 1.3 to 24.1, p = 0.02). In conclusion, cTnT is detectable in 93% of patients with infective endocarditis using a novel highly sensitive assay, with higher levels correlating with poor clinical outcomes.

[Endocarditis with negative blood cultures and immunological alterations: a grand challenge]

Subacute Infectious endocarditis can present immunological phenomena and extracardiac manifestations such as anemia and musculoskeletal pain which can mimic rheumatological disease. It is related a case on infectious endocarditis presenting symptomatology similar to Polymyalgia Rheumatica despite acute nephritis after antibiotic. The differential diagnostic features of Libman-Sacks endocarditis versus infective endocarditis are discussed.

Procalcitonin in 759 patients clinically suspected of infective endocarditis

BACKGROUND

diagnostic delay contributes to high morbidity and mortality in infective endocarditis. A readily available diagnostic marker of infective endocarditis is desirable. S-procalcitonin has been proposed as a candidate, but data on its yield are conflicting. We tested its diagnostic value in a large population of patients seen in a tertiary center.

METHODS

this prospective study included 759 consecutive patients referred for echocardiographic examination on clinical suspicion of infective endocarditis. Transthoracic echocardiography was followed by immediate transesophageal examination, and a blood sample was obtained for procalcitonin analysis. Infective endocarditis was diagnosed by an interdisciplinary team and confirmed according to the Duke criteria. The team was unaware of the results of procalcitonin analyses.

RESULTS

infective endocarditis was present in 147 patients (19%). Procalcitonin was higher in these patients than in those in whom infective endocarditis was rejected (median, 0.21 ng/mL vs. 0.13 ng/mL; P <.0005). Multivariate analysis identified significant independent determinants of high procalcitonin: blood culture with endocarditis-typical microorganisms (odds ratio [OR], 2.81), temperature ≥ 38°C (OR, 2.61), symptoms ≤ 5 days (OR, 2.39), immunocompromised status (OR, 1.74), and male gender (OR, 1.61). Tests at various procalcitonin thresholds yielded an acceptable sensitivity of 95% at 0.04 ng/mL, but specificity was only 14%. Only 12% had procalcitonin below this threshold, which might justify postponement of further examinations for infective endocarditis.

CONCLUSIONS

procalcitonin was significantly higher in patients with infective endocarditis than in patients without infective endocarditis and bacteremia with endocarditis-typical organisms was the strongest independent determinant of high procalcitonin. The clinical importance of this is questionable, because a suitable procalcitonin threshold for diagnosing or excluding infective endocarditis was not established.

Mechanism of outside-in {alpha}IIb{beta}3-mediated activation of human platelets by the colonizing Bacterium, Streptococcus gordonii

OBJECTIVE

To better understand the mechanism of platelet recruitment and activation by Streptococcus gordonii. The oral bacterium Streptococcus gordonii, is amongst the most common pathogens isolated from infective endocarditis patients, and has the property of being able to activate platelets, leading to thrombotic complications. The mechanism of platelet recruitment and activation by S. gordonii is poorly understood.

METHODS AND RESULTS

Infective endocarditis is a bacterial infection of the heart valves that carries a high risk of morbidity and mortality. The oral bacterium, S gordonii, is among the most common pathogens isolated from patients with infective endocarditis and is able to activate platelets, leading to thrombotic complications. Platelets interact with S gordonii via glycoprotein Ibα- and α(IIb)β(3)-recognizing S gordonii surface proteins haemaglutitin salivary antigen (Hsa) and platelet adherence protein A, respectively. The inhibition of glycoprotein Ibα or α(IIb)β(3) using blocking antibodies or deletion of S gordonii Hsa or platelet adherence protein A significantly reduces platelet adhesion. Immunoreceptor tyrosine-based activation motif (ITAM)-containing proteins have recently played a role in transmitting activating signals into platelets. Platelet adhesion to immobilized S gordonii resulted in tyrosine phosphorylation of the ITAM-bearing receptor, FcγRIIa, and phosphorylation of downstream effectors (ie, spleen tyrosine kinase [Syk] and phospholipase C [PLC]-γ2). Tyrosine phosphorylation of FcγRIIa resulted in platelet-dense granule secretion, filopodial and lamellipodial extension, and platelet spreading. Inhibition of FcγRIIa ablated both dense granule release and platelet spreading.

CONCLUSIONS

Streptococcus gordonii binding to the α(IIb)β(3)/FcγRIIa integrin/ITAM signaling complex results in platelet activation that likely contributes to the thrombotic complications of infective endocarditis.

Bovine tricuspid endocarditis as a cause of increased serum concentration of cardiac troponins

A Holstein cow presented for weight loss and anorexia had tachycardia, heart murmur, and a chronic inflammatory process. Serum cardiac troponin I was increased at 3.52 ng/mL. Transthoracic echocardiography revealed a thickened tricuspid valve and comet-tail artifacts compatible with gas in the affected area. This report suggests that serum cardiac troponin I may be increased in bacterial endocarditis in cattle.

[Diagnostics of inflammation activity in infectious endocarditis]

This work was designed to analyse dynamics of inflammation markers (C-reactive protein, TNF-alpha) and procalcitonin in 66 patients with infectious endocarditis (IE) followed up during 6 months. Comparison of clinical observations and laboratory data revealed specific trends in these parameters in patients with different clinical course of IE and at its different stages. Some of the changes are shown to be responsible for the unfavourable prognosis of IE. TNF-alpha levels are considered to be a sensitive and informative index of the patients" clinical conditions throughout the entire period of IE evolvement.

[PCR rDNA 16S used for the etiological diagnosis of blood culture negative endocarditis]

We report the case of a 55 year-old man presenting with a double aortic and mitral endocarditis for which resected valve culture was repeatedly negative. Specific PCR made on valves because of highly positive blood tests for Bartonella henselae remained negative. A molecular approach was made with 16S rDNA PCR, followed by sequencing. Bartonella quintana was identified as the etiology of endocarditis. B. quintana, "fastidious" bacteria, even if hard to identify in a laboratory, is often reported as a blood culture negative endocarditis (BCNE) agent. Molecular biology methods have strongly improved the diagnosis of BCNE. We propose a review of the literature focusing on the interest of broad-spectrum PCR on valve for the etiological diagnosis of BCNE.

Isolated angiitis of the CNS and bacterial endocarditis: similarities and differences

Both isolated angiitis of the central nervous system (IAN) and bacterial endocarditis (BE) may present with similar clinical and auxiliary findings. The differentiation is extremely important because of the different treatment regimens. We compared the findings of six patients with biopsy-proven IAN with the data of six patients with BE. Patients with IAN were younger (27-62 years) and presented with multiple strokes (n = 4), intracerebral hemorrhage (n = 1), epileptic seizures (n = 2), or encephalopathy (n = 1). All IAN patients had pathologic cerebrospinal fluid (CSF) findings (pleocytosis n = 5; protein elevation n = 4), and angiography revealed multilocular stenoses in two cases while digital subtraction angiography was normal in four. BE patients (32-77 years) presented multiple (n = 3) or single ischemic strokes (n = 2) or encephalopathy and headache (n = 2). While all patients showed inflammatory serum findings (C-reactive protein n = 6, leucocytosis n = 4), CSF-pleocytosis was present in two cases only. Angiography revealed a vasculitic pattern in two patients. The diagnosis of BE was established based on transesophageal echocardiography and blood cultures. Leptomeningeal and brain biopsies performed in two cases were normal. Both IAN and BE may present multiple strokes and encephalopathy. The frequency of a vasculitic pattern in angiography is similar in both conditions. While inflammatory serum findings are the rule in BE, pathologic CSF findings were present in all IAN patients. Transesophageal echocardiography and blood cultures should be performed in order to diagnose or exclude BE. Without brain biopsy, immunosuppressive therapy may be dangerous in suspected IAN.

Patients with infective endocarditis and increased cardiac troponin I levels have a higher incidence of in-hospital mortality and valve replacement than those with normal cardiac troponin I levels

OBJECTIVES

To investigate the association of increased cardiac troponin I levels with in-hospital mortality and valve replacement in patients with infective endocarditis (IE).

METHODS

The 62 patients included 36 men and 26 women, with a mean age of 60 +/- 9 years, with IE diagnosed by the Duke criteria. All 62 patients had blood drawn for measurement of cardiac troponin I levels. A cardiac troponin I level >0.4 ng/ml was considered increased. All 62 patients underwent transesophageal echocardiography. Student's t tests were used to analyze continuous variables. chi(2) tests were used to analyze dichotomous variables.

RESULTS

Transesophageal echocardiography diagnosed valvular vegetations in 56 of the 62 patients (90%). Cardiac troponin I levels were increased in 35 of the 62 patients (57%). In-hospital mortality or valve replacement occurred in 18 of 35 patients (51%) with increased cardiac troponin I levels versus 4 of 27 patients (15%) with normal cardiac troponin I levels (p < 0.005).

CONCLUSIONS

Patients with IE and increased cardiac troponin I levels have a higher incidence of in-hospital mortality or valve replacement than those with normal cardiac troponin I levels.

Extension of antimicrobial treatment in patients with left-sided native valve endocarditis based on elevated C-reactive protein values

The aim of this non-randomized study was to investigate whether there is any benefit in the extension of antimicrobial treatment in patients with left-sided native valve endocarditis in whom C-reactive protein levels are still elevated after a standard course of therapy. There was no statistically significant difference in outcome between the group of patients in which treatment was extended in comparison to the group in which treatment was ended at the recommended time. It is unlikely that there is much to gain from extending treatment based on elevated C-reactive protein levels alone.

An unusual case of infective endocarditis presenting as acute myocardial infarction

A 39-year-old Zimbabwean man presented with a 1 week history of fever, general malaise and acute-onset chest pain. He had a urethral stricture, which had been managed with an indwelling supra-pubic catheter. The electrocardiography on admission showed inferior ST-T segments elevation. His chest pain and electrocardiography changes resolved subsequent to thrombolysis, and he remained haemodynamically stable. The 12-h troponin I was increased at 10.5 microg/l (NR <0.04 microg/l). Echocardiography confirmed severe mitral regurgitation and a flail anterior mitral valve leaflet with an independently oscillating mobile vegetation. Enterococci faecalis were grown on blood cultures. A diagnosis of enterococci infective endocarditis with concomitant acute myocardial infarction due to possible septic emboli was made. Despite the successful outcome from thrombolysis in the setting of acute myocardial infarction with infective endocarditis, the case highlights the current lack of definitive data on the optimal acute management of such an unusual clinical scenario. Although there is serious concern that thrombolytic treatment for myocardial infarction in the setting of infective endocarditis may be associated with higher risk of cerebral haemorrhage, there is little documented evidence supporting the safety of primary percutaneous coronary intervention with these patients.

Mannan-binding lectin is a determinant of survival in infective endocarditis

Mannan-binding lectin (MBL) is a collectin plasma protein activating the lectin pathway of the complement system, enhancing opsonophagocytosis and modulating the cytokine response to inflammation. Deficiency of MBL, caused by structural mutations or promoter polymorphisms in the MBL2 gene, has been associated with increased susceptibility to infection and autoimmune disease. Thus, as infective endocarditis remains a severe disease requiring intensive and long-term treatment with antibiotics, we examined whether there was an association between MBL and clinical outcome in 39 well-characterized patients with infective endocarditis. Five patients (13%) had MBL concentrations < 100 microg/l and were considered MBL-deficient. This proportion was similar to that in a healthy control group of blood donors. Mortality 3 months after diagnosis was 20% in patients with MBL-deficiency and 9% in patients with normal MBL. The 5-year mortality was 80% and 25%, respectively. MBL-deficiency was on univariate survival statistics associated with significantly higher mortality on follow-up (P=0 x 03). In conclusion, this is the first report of an association between MBL-deficiency and survival in infective endocarditis. The present observation is important, as replacement therapy in MBL-deficient patients is possible. For certain high-risk subgroups, it opens new perspectives for improvement of treatment and outcome in infective endocarditis.

Prognostic value of N-terminal pro-B-type natriuretic peptide in patients with active infective endocarditis

Our aim was to determine whether N-terminal pro-B-type natriuretic peptide (NT-pro-BNP) and cardiac troponin I (cTnI) levels are valuable for predicting prognosis in patients with infective endocarditis (IE). We analyzed measured plasma NT-pro-BNP levels at admission in 45 patients with definite IE. The primary end point was early surgery or in-hospital death. The other data recorded were baseline clinical, echocardiographic, and laboratory parameters. Thirty patients underwent early surgery, and 9 died in hospital. Univariate analysis revealed that log NT-pro-BNP, cTnI > or =0.03 ng/ml, New York Heart Association functional class III to IV symptoms, left atrial diameter, left ventricular end-diastolic diameter, left ventricular end-systolic diameter, and severe valvular regurgitation were associated with increased risk of reaching the primary end point. Cox proportional hazard regression analysis identified log NT-pro-BNP (hazard ratio 1.5; 95% confidence interval 1.2 to 1.9, p <0.001) as the only independent predictor of the primary end point. The log NT-pro-BNP cut-off value with the highest sensitivity (97%) and specificity (92%) for predicting primary end point was 7.2 (1,500 pg/ml). Patients with NT-pro-BNP level > or =1,500 pg/ml had significantly lower event-free survival than others. In conclusion, admission NT-pro-BNP is of prognostic value in patients with IE. The combination of admission NT-pro-BNP and cTnI levels appears to have even greater value for risk stratification in this patient group.

From acute Q fever to endocarditis: serological follow-up strategy

The serological evolution from acute Q fever to endocarditis is reported for 22 patients, with a median lag time of 3 months. From this data, we propose a follow-up strategy of serological testing at the third and sixth months after acute Q fever to obtain an early diagnosis of chronic infection.

Cytoplasmic antineutrophil cytoplasmic antibody positive pauci-immune glomerulonephritis associated with infectious endocarditis

Renal deterioration often occurs in cases of infectious endocarditis (IE), but, IE- associated nephritis with rapidly progressive glomerulonephritis (RPGN) is rare. Patients with severe infection (e.g., IE) sometimes show positivity for cytoplasmic antineutrophil cytoplasmic antibodies (C-ANCA). Therefore, diagnosis and treatment are very difficult in cases of RPGN with IE and positivity for C-ANCA. Such cases are rare, only 12 have been reported in the English literature. Herein, we describe the case of a 50-year-old man who presented with RPGN with IE and tested positively for C-ANCA. He was referred to our hospital because of leg edema, purpura and renal dysfunction. Laboratory tests revealed serum creatinine elevation and positivity for C-ANCA and proteinase 3-specific (PR3)-ANCA. RPGN and acute renal failure were diagnosed. Hemodialysis and steroid therapy were started. Streptococcus oralis was isolated by blood culture. Transthoracic echocardiography revealed grade III mitral valve insufficiency with two vegetations. Therefore, IE was diagnosed. The steroid therapy was stopped, and antibiotic therapy was begun. Because there was no improvement, surgical therapy was performed. The operation was successful, but the patient died of brain hemorrhage. Our experience in this case indicates C/PR3-ANCA positive RPGN must be ruled out in patients with infectious disease, particularly IE, together with renal symptoms, and renal biopsy should be performed.

[Difficulties in the differential diagnosis of splenic infarction and splenic abscess in a patient with active infective endocarditis -- case report and current review]

Systemic embolization is the most common extracardiac complication of active infective endocarditis (IE). The assessment of individual patient risk for embolic events in active IE is very difficult. Staphylococcal or fungal endocarditis, infections caused by HACEK and Abiotrophia spp. microorganisms, anterior mitral leaflet vegetations and vegetations with size >10 mm in TTE are associated with higher rate of arterial embolization. In this report we present a 66-year-old patient with active enterococcal aortic native valve endocarditis, with a history of gastric ulcers and with acute abdominal pain due to splenic infarction. We conclude that abdominal pain, particularly in the left-upper-quadrant, may be a sign of splenic infarction. Confirmation of this complication by ultrasonography provides important information about increased risk of future systemic embolic events.

Negative Blood Culture Infective Endocarditis in the Elderly: Long-Term Follow-Up

<i>Background and Aim:</i> Since the appearance of transesophageal echocardiography, the long-term prognosis of patients with negative blood culture infective endocarditis (NBCIE) has been found to be similar to that of patients with positive blood culture infective endocarditis (PBCIE). Nevertheless, the prognostic implications of NBCIE in the elderly (>65 years) has not, to date, been well documented. Our aim was to study the long-term prognosis of elderly patients with NBCIE and compare it with that of elderly patients with PBCIE. <i>Methods:</i> Our study group was composed of 60 consecutive patients >65 years old with a diagnosis of IE (confirmed by vegetation analysis or following Duke’s criteria). Every patient underwent transthoracic and transesophageal echocardiography. Fifty patients (83.3%) had PBCIE and 10 (16.7%) had NBCIE. All patients were followed up long-term, and the study end point was a composite one of death or need for valvular heart surgery. <i>Results:</i> Mean age was 72.9 ± 5 years (56.7% male). Similar clinical and echocardiographic characteristics were found in both groups. Global mortality, need for surgery, predisposing factors and infection location were also similar in both groups. In addition, no differences were found in the long-term prognosis (log rank p = 0.29). <i>Conclusions:</i> In our series, the long-term prognosis in elderly patients with IE is independent of the presence of a negative or positive blood culture. Thus, age cannot be considered an independent risk factor of negative outcome in elderly patients with NBCIE.

[Modern aspects of diagnostics of bacterial endocarditis]

Modern approaches to diagnostics of infective endocarditis (IE) are considered in the article. Possibilities for detection of the disease provided by various diagnostic criteria are analyzed. The authors demonstrate the advantages of improved criteria and present the diagnostic signs of subacute endocarditis in congenital heart diseases, artificial valve IE, and IE in drug addicts. Differential diagnostics issues are covered as well.

Corpuscular Antigenic Microarray for the Serodiagnosis of Blood Culture-Negative Endocarditis

Blood culture-negative endocarditis is due to fastidious bacteria, including Coxiella burnetii and Bartonella spp. Diagnosis of such infection relies on serology and microimmunofluorescence is therefore the reference method. We developed a multiplex serology test featuring automatic incubation and reading and incorporating internal controls. Preliminary results indicate that this new serologic test is valuable for the rapid, automated serological diagnosis of blood culture-negative endocarditis.

[Endocarditis due to Bartonella spp. Three new clinical cases and Spanish literature review]

INTRODUCTION

Infections by Bartonella spp. include a wide spectrum of emerging and re-emerging infectious diseases, such as culture-negative endocarditis.

METHODS

Description of 3 cases of endocarditis due to Bartonella spp. and review of those previously reported in Spain.

RESULTS

Including these 3 new cases of endocarditis due to Bartonella spp., a total of 6 cases have been reported in Spain. The median age of the patients was 51.6 years and 83.3% were men. There was history of contact with cats in 66.7%, and 50% were alcoholic. Only one patient had prior valvular disease. There were no clinical manifestations typical to any of the Bartonella species. The aortic valve was the one most commonly affected. In all cases, B. henselae was the agent implicated. The diagnosis was made by serology in 5 cases (83.3%). The outcome was favorable in all patients, although 4 of them (66.7%) required valve replacement.

CONCLUSION

Endocarditis due to Bartonella spp. is present in Spain and is likely to be underestimated. We should suspect this pathogen in patients with negative blood cultures and a history of chronic alcoholism, homeless patients, and those who have had contact with cats or who have been bitten by fleas or lice, as well as patients with endocarditis and positive serology against Chlamydia spp.

New insight into the diagnosis of fastidious bacterial endocarditis

Sterile blood cultures are noted in one third of patients with infectious endocarditis. Although in half of cases this is due to previous antibiotic therapy, in the other half, the aetiology of culture-negative endocarditis is intracellular bacteria such as Coxiella burnetii or fastidious growing bacteria. Although it was previously considered that the prevalence of such organisms was identical throughout the world, recent investigations on Bartonella endocarditis clearly showed that the aetiology of culture-negative endocarditis is likely to be strongly related to epidemiology of the agent in each country. During the past decade the use of molecular techniques such as PCR with subsequent sequencing to detect or to identify bacteria in valves from patients with infectious endocarditis have considerably improved the aetiological diagnosis. This is especially true in the case of culture-negative endocarditis following earlier antibiotic therapy. However, the fact that DNA remnants of past endocarditis can be detected some time after the acute episode, when the patient has been cured, suggests that the predictive value of these techniques along with the traditional histology and culture need to be evaluated closely.

[Fulminant pneumococcal pancarditis and acute myocardial infarction with cardiac failure]

Streptococcus pneumoniae is an infrequent cause of endocarditis in adults. Typically occurs in individuals with debilitating illnesses as alcoholism. Frequently the course is aggressive, with rapid destruction of valves. It is associated with high mortality. We describe a young patient without underlying illnesses with pneumococcal endocarditis and meningitis of fulminant course diagnosed in postmorten examination.

The serological diagnosis of staphylococcal infective endocarditis

OBJECTIVES

Establishing the diagnosis of infective endocarditis (IE) can be difficult when blood cultures remain sterile or echocardiography is inconclusive. Staphylococcus aureus is a common aetiological microorganism in IE and is associated with severe valvular destruction and increased mortality. Early diagnosis using culture and antibiotic independent tests would be preferable to allow prompt antibiotic administration. We have developed and evaluated 2 serological assays for the rapid identification of a staphylococcal aetiology in infective endocarditis. The assays measure IgG against whole cells of S. aureus and IgG against lipid S, a novel extracellular antigen released by Gram-positive microorganisms.

METHODS

Serum was collected from 130 patients with IE and 94 control patients. IgG against whole cells of S. aureus and against lipid S was measured by enzyme linked immunosorbent assay (ELISA).

RESULTS

Anti-lipid S IgG titres were higher in IE caused by Gram-positive microorganisms than in controls (p<0.0001) and higher in staphylococcal IE than in both controls and IE caused by other microorganisms (p=0.0003). Anti-whole cell staphylococcal IgG was significantly higher in serum from patients with staphylococcal IE than in IE caused by other microorganisms and control samples (p<0.0001).

CONCLUSION

High anti-whole cell IgG titres are predictive of a staphylococcal aetiology in IE. Elevated serum anti-lipid S IgG titres are predictive of Gram-positive infection compared to controls, very high titres being associated with staphylococcal IE.

[Results of observation of infective endocarditis patients during 1965-2005]

AIM

To clarify the trends in infective endocarditis by our experience for 40 years.

MATERIAL AND METHODS

During the last 40 years (1965-2005) we observed 620 patients with infective endocarditis (IE). There were 615 patients with subacute IE (99.2%) and only 5 patients with acute IE (0.8%). There were 402 males (66.8%) and 218 females (35.2%). The age was 16-84 years (mean age 53 +/- 17). We studied the finding of hemoculture, echocardiography, immunological investigations, the levels of C-reactive protein.

RESULTS

Streptococcal endocarditis runs a standard course, but more often we encountered staphylococcal, enterococcal endocarditis with a severe course. Predisposing cardiac disorders in 264 IE patients were rheumatic heart disease, congenital heart disease, mitral prolapse, involutive valve disease, hypertrophic cardiomyopathy, prosthetic valve.

CONCLUSION

Conventional and unconventional IE cases, recurrent IE, current criteria of IE are described.

[Parallels in clinical, laboratory and instrumental data between systemic lupus erythematosus and infectious endocarditis in children]

The aim of the study was the comparison of clinical, laboratory end instrumental data between systemic lupus erythematosus (SLE) end infectious endocarditis (IE) for analysis of similar and different features. Clinical, laboratory and instrumental data were analysed and compared for 96 SLE and 23 IE patients. SLE and IE have the following common features: fever, pleurisy, pericarditis, myocarditis hemorrhagic vasculitis, renal disorders, anaemia, concentrations of circulating immune complex (CIC), IgM. Characteristic of SLE were skin erythema, alopecia, cerebrovasculitis, lymhadenopathy, pneumonitis, frequent articular lesions, pancytopenia, high IgG levels, and antibodies to DNA. After echocardiographic investigations a rare revelation of the damage of endocardium, and the lack of destruction of the valve were detected. IE was characterized by thromboembolic complications, splenomegaly, pneumonia, high IgM levels, high incidence rate of RF, positive hemoculture. By echocardiographic studies bacterial vegetations end valvular pathology were detected. These data gives us the possibility for early differential diagnostics of these two diseases.

[Significance of C-reactive protein detection in patients with primary infective myocarditis]

The importance of the problem of primary infective endocarditis (PIE) has become much greater during the last years due to an increase in its incidence, serious early diagnostic difficulties, and high lethality, which makes study of its new diagnostic criteria necessary. The paper presents data on the role of C-reactive protein (CRP) in PIE diagnosis. The authors show that high CRP levels evidence prominent infective-and-toxic manifestations of the disease and that dynamic measurement of CRP levels in patients with infective myocarditis allows monitoring the effectiveness of the therapy and may be applied to the prognosis of the disease.

Decreased virulence of a gls24 mutant of Enterococcus faecalis OG1RF in an experimental endocarditis model

In the current study, the gls24 disruption mutant TX10100, previously shown to be more sensitive to bile salts and attenuated in a mouse peritonitis model, showed an approximately fivefold higher 50% infective dose than wild-type OG1RF in a rat endocarditis model. When administered as a mixture, TX10100, unlike a downstream glsB mutant, was significantly outnumbered by OG1RF in vegetations, organs, and blood, despite being inoculated in greater numbers. These results indicate that gls24 is important in the pathogenesis of enterococcal endocarditis.

Streptococcus viridans endocarditis from tongue piercing

Body piercing and tattooing have undergone a revival in popularity. We present the case of a 27-year-old man with a recent tongue piercing and infective endocarditis of the aortic valve. He was treated with a 6-week course of intravenous antibiotics, but eventually required a Ross procedure for progressive aortic insufficiency.