Fatal Serratia marcescens meningitis and myocarditis in a patient with an indwelling urinary catheter.
(1/1509)
Serratia marcescens is commonly isolated from the urine of patients with an indwelling urinary catheter and in the absence of symptoms is often regarded as a contaminant. A case of fatal Serratia marcescens septicaemia with meningitis, brain abscesses, and myocarditis discovered at necropsy is described. The patient was an 83 year old man with an indwelling urinary catheter who suffered from several chronic medical conditions and from whose urine Serratia marcescens was isolated at the time of catheterisation. Serratia marcescens can be a virulent pathogen in particular groups of patients and when assessing its significance in catheter urine specimens, consideration should be given to recognised risk factors such as old age, previous antibiotic treatment, and underlying chronic or debilitating disease, even in the absence of clinical symptoms. (+info)
Enteroviral RNA replication in the myocardium of patients with left ventricular dysfunction and clinically suspected myocarditis.
(2/1509)
BACKGROUND: Previous studies dealing with the detection of enteroviral RNA in human endomyocardial biopsies have not differentiated between latent persistence of the enteroviral genome and active viral replication. Enteroviruses that are considered important factors for the development of myocarditis have a single-strand RNA genome of positive polarity that is transcribed by a virus-encoded RNA polymerase into a minus-strand mRNA during active viral replication. The synthesis of multiple copies of minus-strand enteroviral RNA therefore occurs only at sites of active viral replication but not in tissues with mere persistence of the viral genome. METHODS AND RESULTS: We investigated enteroviral RNA replication versus enteroviral RNA persistence in endomyocardial biopsies of 45 patients with left ventricular dysfunction and clinically suspected myocarditis. Using reverse-transcriptase polymerase chain reaction in conjunction with Southern blot hybridization, we established a highly sensitive assay to specifically detect plus-strand versus minus-strand enteroviral RNA in the biopsies. Plus-strand enteroviral RNA was detected in endomyocardial biopsies of 18 (40%) of 45 patients, whereas minus-strand RNA as an indication of active enteroviral RNA replication was detected in only 10 (56%) of these 18 plus-strand-positive patients. Enteroviral RNA was not found in biopsies of the control group (n=26). CONCLUSIONS: These data demonstrate that a significant fraction of patients with left ventricular dysfunction and clinically suspected myocarditis had active enteroviral RNA replication in their myocardium (22%). Differentiation between patients with active viral replication and latent viral persistence should be particularly important in future studies evaluating different therapeutic strategies. In addition, molecular genetic detection of enteroviral genome and differentiation between replicating versus persistent viruses is possible in a single endomyocardial biopsy. (+info)
Chlamydia infections and heart disease linked through antigenic mimicry.
(3/1509)
Chlamydia infections are epidemiologically linked to human heart disease. A peptide from the murine heart muscle-specific alpha myosin heavy chain that has sequence homology to the 60-kilodalton cysteine-rich outer membrane proteins of Chlamydia pneumoniae, C. psittaci, and C. trachomatis was shown to induce autoimmune inflammatory heart disease in mice. Injection of the homologous Chlamydia peptides into mice also induced perivascular inflammation, fibrotic changes, and blood vessel occlusion in the heart, as well as triggering T and B cell reactivity to the homologous endogenous heart muscle-specific peptide. Chlamydia DNA functioned as an adjuvant in the triggering of peptide-induced inflammatory heart disease. Infection with C. trachomatis led to the production of autoantibodies to heart muscle-specific epitopes. Thus, Chlamydia-mediated heart disease is induced by antigenic mimicry of a heart muscle-specific protein. (+info)
From myocarditis to cardiomyopathy: mechanisms of inflammation and cell death: learning from the past for the future.
(4/1509)
A progression from viral myocarditis to dilated cardiomyopathy has long been hypothesized, but the actual extent of this progression has been uncertain. However, a causal link between viral myocarditis and dilated cardiomyopathy has become more evident than before with the tremendous developments in the molecular analyses of autopsy and endomyocardial biopsy specimens, new techniques of viral gene amplification, and modern immunology. The persistence of viral RNA in the myocardium beyond 90 days after inoculation, confirmed by the method of polymerase chain reaction, has given us new insights into the pathogenesis of dilated cardiomyopathy. Moreover, new knowledge of T-cell-mediated immune responses in murine viral myocarditis has contributed a great deal to the understanding of the mechanisms of ongoing disease processes. Apoptotic cell death may provide the third concept to explain the pathogenesis of dilated cardiomyopathy, in addition to persistent viral RNA in the heart tissue and an immune system-mediated mechanism. Beneficial effects of alpha1-adrenergic blocking agents, carteolol, verapamil, and ACE inhibitors have been shown clinically and experimentally in the treatment of viral myocarditis and dilated cardiomyopathy. Antiviral agents should be more extensively investigated for clinical use. The rather discouraging results obtained to date with immunosuppressive agents in the treatment of viral myocarditis indicated the importance of sparing neutralizing antibody production, which may be controlled by B cells, and raised the possibility of promising developments in immunomodulating therapy. (+info)
Global biventricular dysfunction in patients with asymptomatic coronary artery disease may be caused by myocarditis.
(5/1509)
BACKGROUND: The causal role of asymptomatic critical coronary artery obstruction in patients presenting with severe global biventricular dysfunction but no evidence of myocardial infarction is uncertain. METHODS AND RESULTS: Among 291 patients aged >40 years undergoing a noninvasive (2-dimensional echocardiography) and invasive (catheterization, coronary angiography, and biventricular endomyocardial biopsy, 6 to 8 samples/patient) cardiac study because of progressive heart failure (New York Heart Association functional class III or IV) with global biventricular dysfunction and no history of myocardial ischemic events, 7 patients (2.4%; 7 men; mean age, 49+/-6.9 years) had severe coronary artery disease (3 vessels in 4 patients; 2 vessels in 1 patient, proximal occlusion of left anterior descending coronary artery in 2 patients). Left ventricular end-diastolic diameter and ejection fraction by 2-dimensional echocardiography were 73+/-10.5 mm and 23+/-6.5%, respectively, and right ventricular end-diastolic diameter and ejection fraction were 39+/-7 mm and 29+/-7.2%, respectively. Biopsy specimens showed extensive lymphocytic infiltrates with focal myocytolysis meeting the Dallas criteria for myocarditis in all patients (in 5 patients with and 2 patients without fibrosis). Cardiac autoantibodies were detected with indirect immunofluorescence in the serum of 2 patients with active myocarditis. The 2 patients with active inflammation received prednisone (1 mg. kg-1. d-1 for 4 weeks followed by 0.33 mg. kg-1. d-1 for 5 months) and azathioprine (2 mg. kg-1. d-1 for 5 months) in addition to conventional drug therapy for heart failure. At 8-month overall follow-up, cardiac volume and function improved considerably in immunosuppressed patients but remained unchanged in conventionally treated patients, of whom 1 died. CONCLUSIONS: Global biventricular dysfunction in patients with severe asymptomatic coronary artery disease and no evidence of previous myocardial infarction may be caused by myocarditis. Histologic findings may influence the treatment. (+info)
Detection of adenoviral genome in the myocardium of adult patients with idiopathic left ventricular dysfunction.
(6/1509)
BACKGROUND: The use of molecular biological techniques has demonstrated the importance of enteroviral infection of the myocardium in the pathogenesis of myocarditis and dilated cardiomyopathy in adults and adenovirus and enterovirus infection in children. The aim of this study was to determine the frequency of adenoviral infection of the myocardium of adults with impaired left ventricular function of unknown origin. METHODS AND RESULTS: Nested polymerase chain reaction (nPCR) was used to determine the frequency of detection of adenoviral DNA and enteroviral RNA in myocardial tissue samples from 94 adult patients with idiopathic left ventricular dysfunction and 14 control patients. Histological and immunohistological analyses were performed to detect myocardial inflammation. Adenoviral genomic DNA was detected by nPCR in 12 of the 94 patients with left ventricular dysfunction (in each case, adenovirus type 2), whereas enteroviral RNA was detected in another 12 patients. All control samples were negative for both viruses. In all patients, active myocarditis was excluded according to the Dallas criteria. However, there was significantly decreased CD2, CD3, and CD45RO T lymphocyte counts in the adenovirus-positive group compared with the adenovirus-negative group (P<0.05), whereas no differences were associated with enterovirus infection. CONCLUSIONS: Although enteroviruses are an important causative agent in the pathogenesis of myocarditis and dilated cardiomyopathy, this study shows that adenovirus infection is also important in the pathogenesis of left ventricular failure in adults. However, the pathogenetic basis of disease associated with adenovirus infection may be different than that after infection with other agents, particularly with respect to activation of the host immune response. (+info)
A case of eosinophilic myocarditis complicated by Kimura's disease (eosinophilic hyperplastic lymphogranuloma) and erythroderma.
(7/1509)
This report describes a patient with eosinophilic myocarditis complicated by Kimura's disease (eosinophilic hyperplastic lymphogranuloma) and erythroderma. A 50-year-old man presented with a complaint of precordial pain. However, the only abnormal finding on examinatioin was eosinophilia (1617 eosinophils/microl). Three years later, the patient developed chronic eczema, and was diagnosed with erythroderma posteczematosa. One year later, a tumor was detected in the right auricule, and a diagnosis of Kimura's disease was made, based on the biopsy findings. The patient developed progressive dyspnea 6 months later and was found to have cardiomegaly and a depressed left ventricular ejection fraction (17%). A diagnosis of eosinophilic myocarditis was made based on the results of a right ventricular endomyocardial biopsy. The eosinophilic myocarditis and erythrodrema were treated with steroids with improvement of both the eosinophilia and left ventricular function. (+info)
Rheumatic chorea in northern Australia: a clinical and epidemiological study.
(8/1509)
To describe the epidemiology and clinical features of Sydenham's chorea in the Aboriginal population of northern Australia a review was conducted of 158 episodes in 108 people: 106 were Aborigines, 79 were female, and the mean age was 10.9 years at first episode. Chorea occurred in 28% of cases of acute rheumatic fever, carditis occurred in 25% of episodes of chorea, and arthritis in 8%. Patients with carditis or arthritis tended to have raised acute phase reactants and streptococcal serology. Two episodes lasted at least 30 months. Mean time to first recurrence of chorea was 2.1 years compared with 1.2 years to second recurrence. Established rheumatic heart disease developed in 58% of cases and was more likely in those presenting with acute carditis, although most people who developed rheumatic heart disease did not have evidence of acute carditis with chorea. Differences in the patterns of chorea and other manifestations of acute rheumatic fever in different populations may hold clues to its pathogenesis. Long term adherence to secondary prophylaxis is crucial following all episodes of acute rheumatic fever, including chorea, to prevent recurrence. (+info)