Clinical presentation, etiology, and outcome of infective endocarditis in the 21st century: the International Collaboration on Endocarditis-Prospective Cohort Study.

We sought to provide a contemporary picture of the presentation, etiology, and outcome of infective endocarditis (IE) in a large patient cohort from multiple locations worldwide. Prospective cohort study of 2781 adults with definite IE who were admitted to 58 hospitals in 25 countries from June 1, 2000, through September 1, 2005. The median age of the cohort was 57.9 (interquartile range, 43.2-71.8) years, and 72.1% had native valve IE. Most patients (77.0%) presented early in the disease (<30 days) with few of the classic clinical hallmarks of IE. Recent health care exposure was found in one-quarter of patients. Staphylococcus aureus was the most common pathogen (31.2%). The mitral (41.1%) and aortic (37.6%) valves were infected most commonly. The following complications were common: stroke (16.9%), embolization other than stroke (22.6%), heart failure (32.3%), and intracardiac abscess (14.4%). Surgical therapy was common (48.2%), and in-hospital mortality remained high (17.7%). Prosthetic valve involvement (odds ratio, 1.47; 95% confidence interval, 1.13-1.90), increasing age (1.30; 1.17-1.46 per 10-year interval), pulmonary edema (1.79; 1.39-2.30), S aureus infection (1.54; 1.14-2.08), coagulase-negative staphylococcal infection (1.50; 1.07-2.10), mitral valve vegetation (1.34; 1.06-1.68), and paravalvular complications (2.25; 1.64-3.09) were associated with an increased risk of in-hospital death, whereas viridans streptococcal infection (0.52; 0.33-0.81) and surgery (0.61; 0.44-0.83) were associated with a decreased risk. In the early 21st century, IE is more often an acute disease, characterized by a high rate of S aureus infection. Mortality remains relatively high.

Importance of ENaC-mediated sodium transport in alveolar fluid clearance using genetically-engineered mice.

The lung possesses specific transport systems that intra- and extracellularly maintain salt and fluid balance necessary for its function. At birth, the lungs rapidly transform into a fluid (Na(+))-absorbing organ to enable efficient gas exchange. Alveolar fluid clearance, which mainly depends on sodium transport in alveolar epithelial cells, is an important mechanism by which excess water in the alveoli is reabsorbed during the resolution of pulmonary edema. In this review, we will focus and summarize on the role of ENaC in alveolar lung liquid clearance and discuss recent data from mouse models with altered activity of epithelial sodium channel function in the lung, and more specifically in alveolar fluid clearance. Recent data studying mice with hyperactivity of ENaC or mice with reduced ENaC activity clearly illustrate the impaired lung fluid clearance in these adult mice. Further understanding of the physiological role of ENaC and its regulatory proteins implicated in salt and water balance in the alveolar cells may therefore help to develop new therapeutic strategies to improve gas exchange in pulmonary edema.

ENaC-mediated alveolar fluid clearance and lung fluid balance depend on the channel-activating protease 1.

Sodium transport via epithelial sodium channels (ENaC) expressed in alveolar epithelial cells (AEC) provides the driving force for removal of fluid from the alveolar space. The membrane-bound channel-activating protease 1 (CAP1/Prss8) activates ENaC in vitro in various expression systems. To study the role of CAP1/Prss8 in alveolar sodium transport and lung fluid balance in vivo, we generated mice lacking CAP1/Prss8 in the alveolar epithelium using conditional Cre-loxP-mediated recombination. Deficiency of CAP1/Prss8 in AEC induced in vitro a 40% decrease in ENaC-mediated sodium currents. Sodium-driven alveolar fluid clearance (AFC) was reduced in CAP1/Prss8-deficient mice, due to a 48% decrease in amiloride-sensitive clearance, and was less sensitive to beta(2)-agonist treatment. Intra-alveolar treatment with neutrophil elastase, a soluble serine protease activating ENaC at the cell surface, fully restored basal AFC and the stimulation by beta(2)-agonists. Finally, acute volume-overload increased alveolar lining fluid volume in CAP1/Prss8-deficient mice. This study reveals that CAP1 plays a crucial role in the regulation of ENaC-mediated alveolar sodium and water transport and in mouse lung fluid balance.

Diagnosing pulmonary embolism in outpatients with clinical assessment, D-dimer measurement, venous ultrasound, and helical computed tomography: a multicenter management study.

PURPOSE: To evaluate a diagnostic strategy for pulmonary embolism that combined clinical assessment, plasma D-dimer measurement, lower limb venous ultrasonography, and helical computed tomography (CT). METHODS: A cohort of 965 consecutive patients presenting to the emergency departments of three general and teaching hospitals with clinically suspected pulmonary embolism underwent sequential noninvasive testing. Clinical probability was assessed by a prediction rule combined with implicit judgment. All patients were followed for 3 months. RESULTS: A normal D-dimer level (&lt;500 microg/L by a rapid enzyme-linked immunosorbent assay) ruled out venous thromboembolism in 280 patients (29%), and finding a deep vein thrombosis by ultrasonography established the diagnosis in 92 patients (9.5%). Helical CT was required in only 593 patients (61%) and showed pulmonary embolism in 124 patients (12.8%). Pulmonary embolism was considered ruled out in the 450 patients (46.6%) with a negative ultrasound and CT scan and a low-to-intermediate clinical probability. The 8 patients with a negative ultrasound and CT scan despite a high clinical probability proceeded to pulmonary angiography (positive: 2; negative: 6). Helical CT was inconclusive in 11 patients (pulmonary embolism: 4; no pulmonary embolism: 7). The overall prevalence of pulmonary embolism was 23%. Patients classified as not having pulmonary embolism were not anticoagulated during follow-up and had a 3-month thromboembolic risk of 1.0% (95% confidence interval: 0.5% to 2.1%). CONCLUSION: A noninvasive diagnostic strategy combining clinical assessment, D-dimer measurement, ultrasonography, and helical CT yielded a diagnosis in 99% of outpatients suspected of pulmonary embolism, and appeared to be safe, provided that CT was combined with ultrasonography to rule out the disease.

Diagnostic d'embolie pulmonaire: problématique résiduelle des D-dimères faussement positifs [The unresolved issue of false-positive D-dimer results in the diagnostic workup of pulmonary embolism].

The unresolved issue of false-positive D-dimer results in the diagnostic workup of pulmonary embolism Pulmonary embolism (PE) remains a difficult diagnosis as it lacks specific symptoms and clinical signs. After the determination of the pretest PE probability by a validated clinical score, D-dimers (DD) is the initial blood test in the majority of patients whose probability is low or intermediate. The low specificity of DD results in a high number of false-positives that then require thoracic angio-CT. A new clinical decision rule, called the Pulmonary Embolism Rule-out criteria (PERC), identifies patients at such low risk that PE can be safely ruled-out without a DD test. Its safety has been confirmed in US emergency departments, but retrospective European studies showed that it would lead to 5-7% of undiagnosed PE. Alternative strategies are needed to reduce the proportion of false-positive DD results.

Bradykinin in blood and cerebrospinal fluid after acute cerebral lesions: correlations with cerebral edema and intracranial pressure.

Abstract Bradykinin (BK) was shown to stimulate the production of physiologically active metabolites, blood-brain barrier disruption, and brain edema. The aim of this prospective study was to measure BK concentrations in blood and cerebrospinal fluid (CSF) of patients with traumatic brain injury (TBI), subarachnoid hemorrhage (SAH), intracerebral hemorrhage (ICH), and ischemic stroke and to correlate BK levels with the extent of cerebral edema and intracranial pressure (ICP). Blood and CSF samples of 29 patients suffering from acute cerebral lesions (TBI, 7; SAH,: 10; ICH, 8; ischemic stroke, 4) were collected for up to 8 days after insult. Seven patients with lumbar drainage were used as controls. Edema (5-point scale), ICP, and the GCS (Glasgow Coma Score) at the time of sample withdrawal were correlated with BK concentrations. Though all plasma-BK samples were not significantly elevated, CSF-BK levels of all patients were significantly elevated in overall (n=73) and early (≤72 h) measurements (n=55; 4.3±6.9 and 5.6±8.9 fmol/mL), compared to 1.2±0.7 fmol/mL of controls (p=0.05 and 0.006). Within 72 h after ictus, patients suffering from TBI (p=0.01), ICH (p=0.001), and ischemic stroke (p=0.02) showed significant increases. CSF-BK concentrations correlated with extent of edema formation (r=0.53; p<0.001) and with ICP (r=0.49; p<0.001). Our results demonstrate that acute cerebral lesions are associated with increased CSF-BK levels. Especially after TBI, subarachnoid and intracerebral hemorrhage CSF-BK levels correlate with extent of edema evolution and ICP. BK-blocking agents may turn out to be effective remedies in brain injuries.

Transcatheter stent-valve implantation in a stenotic pulmonary conduit via a sub-xyphoidian access

Patients who develop a severe stenosis in biological pulmonary conduits previously implanted for pulmonary outflow trunk reconstructions are treated either by surgical re-replacement, or by transcatheter stent-valve implantation through a femoral vein access. A catheter-based sub-xyphoidian access through the right ventricle for stent-valve positioning in a pulmonary conduit has rarely been proposed. We describe the case of a 20-year-old man who underwent a pulmonary trunk reconstruction for a congenital pulmonary valve dysplasia and a few years later developed a stenosis in the pulmonary conduit. He was successfully treated with a 23 mm Edwards Sapien stent-valve implantation in pulmonary position, through an unusual right ventricular, sub-xyphoidian access and without contrast medium injections and pleura opening.

Le nodule pulmonaire solitaire [The solitary pulmonary nodule]

The incidental discovery of a solitary pulmonary nodule while performing a CT scan of the chest is a very common clinical problem. The differential diagnosis is large but the main clinical challenge is to exclude or ascertain a neoplasia. The evaluation of preexisting risk factors and the analysis of morphological characteristics of the nodule allow the clinician to solve this challenge in a significant number of cases. When the nature of the lesion remains indeterminate a careful follow-up with volumetric determination is necessary for decision making.

Recurrent uveitis, cystoid macular edema and pericarditis in Lyme disease.

Lyme disease has been associated with many systemic and ocular complications. The authors' patient, a 26-year-old man, developed recurrent pars planitis with two episodes of acute pericarditis. Extensive medical investigations were negative except for a highly positive western blot for Borrelia burgdorferi. Specific antibiotic treatment for Lyme disease was followed by a long lasting period without any relapse.

Outpatient treatment of pulmonary embolism.

Pulmonary embolism (PE) is traditionally treated in hospital. Growing evidence from non randomized prospective studies suggests that a substantial proportion of patients with non-massive PE might be safely treated in the outpatient setting using low molecular weight heparins. Based on this evidence, professional societies started to recommend outpatient care for selected patients with non-massive PE. Despite these recommendations, outpatient treatment of non-massive PE appears to be uncommon in clinical practice. The major barriers to PE outpatient care are, firstly, the uncertainty as how to identify low risk patients with PE who are candidates for outpatient care and secondly the lack of high quality evidence from randomized trials demonstrating the safety of PE outpatient care compared to traditional inpatient management. Also, although clinical prognostic models, echocardiography and cardiac biomarkers accurately identify low risk patients with PE in prospective studies, the benefit of risk stratification strategies based on these instruments should be demonstrated in prospective management studies and clinical trials before they can be implemented as decision aids to guide PE outpatient treatment. Before high quality evidence documenting the safety of an outpatient treatment approach is published, outpatient management of non-massive PE cannot be generally recommended.

Therapy of acute massive pulmonary embolism associated with Klippel-Trenaunay syndrome.

Acute massive pulmonary embolism (PE) is a life-threatening event. Before the era of cardiopulmonary bypass, acute pulmonary embolectomy had been historically attempted in patients with severe hemodynamic compromise. The Klippel-Trenaunay syndrome (KTS) represents a significant life-long risk for major thromboembolic events. We present two young patients with Klippel-Trenaunay syndrome who survived surgical embolectomy after massive PE and cardiopulmonary resuscitation, with good postoperative recovery. Even though the role of surgical embolectomy in massive PE is not clearly defined, with current technology it can be life saving and can lead to a complete recovery, especially in young patients as described in this study.

Weekend versus weekday admission and mortality after acute pulmonary embolism.

BACKGROUND: Optimal management of acute pulmonary embolism (PE) requires medical expertise, diagnostic testing, and therapies that may not be available consistently throughout the entire week. We sought to assess whether associations exist between weekday or weekend admission and mortality and length of hospital stay for patients hospitalized with PE. METHODS AND RESULTS: We evaluated patients discharged with a primary diagnosis of PE from 186 acute care hospitals in Pennsylvania (January 2000 to November 2002). We used random-effect logistic models to study the association between weekend admission and 30-day mortality and used discrete survival models to study the association between weekend admission and time to hospital discharge, adjusting for hospital (region, size, and teaching status) and patient factors (race, insurance, severity of illness, and use of thrombolytic therapy). Among 15 531 patient discharges with PE, 3286 patients (21.2%) had been admitted on a weekend. Patients admitted on weekends had a higher unadjusted 30-day mortality rate (11.1% versus 8.8%) than patients admitted on weekdays, with no difference in length of stay. Patients admitted on weekends had significantly greater adjusted odds of dying (odds ratio 1.17, 95% confidence interval 1.03 to 1.34) than patients admitted on weekdays. The higher mortality among patients hospitalized on weekends was driven by the increased mortality rate among the most severely ill patients. CONCLUSIONS: Patients with PE who are admitted on weekends have a significantly higher short-term mortality than patients admitted on weekdays. Quality-improvement efforts should aim to ensure a consistent approach to the management of PE 7 days a week.

Pulmonary hypertension in Switzerland: treatment and clinical course.

The prognosis of pulmonary hypertension (PH), especially idiopathic pulmonary arterial hypertension (IPAH), has improved during the recent years. The Swiss Registry for PH represents the collaboration of the various centres in Switzerland dealing with PH and serves as an important tool in quality control. The objective of the study was to describe the treatment and clinical course of this orphan disease in Switzerland. We analyzed data from 222 of 252 adult patients, who were included in the registry between January 1999 and December 2004 and suffered from either PAH, PH associated with lung diseases or chronic thromboembolic PH (CTEPH) with respect to the following data: NYHA class, six-minute walking distance (6-MWD), haemodynamics, treatments and survival. If compared with the calculated expected figures the one, two and three year mean survivals in IPAH increased from 67% to 89%, from 55% to 78% and from 46% to 73%, respectively. Most patients (90%) were on oral or inhaled therapy and only 10 patients necessitated lung transplantation. Even though pulmonary endarterectomy (PEA) was performed in only 7 patients during this time, the survival in our CTEPH cohort improved compared with literature data and seems to approach outcomes usually seen after PEA. The 6-MWD increased maximally by 52 m and 59 m in IPAH and CTEPH, respectively, but in the long term returned to or below baseline values, despite the increasing use of multiple specific drugs (overall in 51% of IPAH and 29% of CTEPH). Our national registry data indicate that the overall survival of IPAH and presumably CTEPH seems to have improved in Switzerland. Although the 6-MWD improved transiently, it decreased in the long term despite specific and increasingly combined drug treatment. Our findings herewith underscore the progressive nature of the diseases and the need for further intense research in the field.

Adverse effects of industrial multiwalled carbon nanotubes on human pulmonary cells

The aim of this study was to evaluate adverse effects of multiwalled carbon nanotubes (MWCNT), produced for industrial purposes, on the human epithelial cell line A549. MWCNT were dispersed in dipalmitoyl lecithin (DPL), a component of pulmonary surfactant, and the effects of dispersion in DPL were compared to those in two other media: ethanol (EtOH) and phosphate-buffered saline (PBS). Effects of MWCNT were also compared to those of two asbestos fibers (chrysotile and crocidolite) and carbon black (CB) nanoparticles, not only in A549 cells but also in mesothelial cells (MeT5A human cell line), used as an asbestos-sensitive cell type. MWCNT formed agglomerates on top of both cell lines (surface area 15-35 μm2) that were significantly larger and more numerous in PBS than in EtOH and DPL. Whatever the dispersion media, incubation with 100 μg/ml MWCNT induced a similar decrease in metabolic activity without changing cell membrane permeability or apoptosis. Neither MWCNT cellular internalization nor oxidative stress was observed. In contrast, asbestos fibers penetrated into the cells, decreased metabolic activity but not cell membrane permeability, and increased apoptosis, without decreasing cell number. CB was internalized without any adverse effects. In conclusion, this study demonstrates that MWCNT produced for industrial purposes exert adverse effects without being internalized by human epithelial and mesothelial pulmonary cell lines. [Authors]

The Swiss registry for pulmonary arterial hypertension: the paediatric experience.

Pulmonary arterial hypertension is a rare disease with a poor prognosis. Epidemiological data are scarce, particularly in the paediatric population. A registry was recently developed in order to collect epidemiological data on patients with pulmonary arterial hypertension (PAH) in Switzerland. This is the first description of the paediatric data. Paediatric patients aged 0-18 years with the diagnosis of PAH were enrolled in the registry from 1999 to 2005 with informed consent from their parents. Patient characteristics, PAH aetiology, functional capacity, exercise capacity, treatments and outcome were among the most important data collected. A total of 23 patients (12 male, 11 female) have been thus far included in the registry. Median age at time of diagnosis was 3 years (range 1 month-18 years) and median follow-up was 3.47 years (range 1 day-12.6 years). PAH aetiologies are diagnosed as idiopathic in 8/23 patients (34.8%) and associated with congenital heart diseases in 12/23 (52.2%) or with pulmonary diseases in 3/23 patients (13.0%). Death occurred in 1 patient before treatment was initiated. Single treatments include medications with a calcium channel blocker in 2/23 patients, with bosentan in 10/23, and with inhaled iloprost in 1/23. Combined therapies include bosentan and inhaled iloprost in 7/23 patients, bosentan and sildenafil in 2/23 patients, and bosentan, sildenafil and inhaled iloprost in 2/23 patients. Additional oral anticoagulation is given to 14/23 patients and 8/23 patients are on oxygen therapy. NYHA class at baseline visit was obtained in 22/23 patients (4 NYHA 2, 17 NYHA 3 and 1 NYHA 4). Changes in NYHA class were observed over a 2-year period in 3/22 patients who improved from NYHA 3 to NYHA 2. Initial improvement of 6-minute walk distance was observed in 6/13 patients with a sustained improvement in 4. These preliminary results provide information on the epidemiology of PAH in children in Switzerland and demonstrate that most paediatric patients show stabilisation of the disease under new treatments. This underscores the utility of registries for rare diseases in providing crucial information in the era of new therapies. It may also help to improve the future medical approach.