Fatal Epstein-Barr virus myocarditis in a child with repetitive myocarditis

The knowns and unknowns of cardiac autoimmunity in viral myocarditis

Myocarditis can result from various infectious and non-infectious causes that can lead to dilated cardiomyopathy (DCM) and heart failure. Among the infectious causes, viruses are commonly suspected. But the challenge is our inability to demonstrate infectious viral particles during clinical presentations, partly because by that point, the viruses would have damaged the tissues and be cleared by the immune system. Therefore, viral signatures such as viral nucleic acids and virus-reactive antibodies may be the only readouts pointing to viruses as potential primary triggers of DCM. Thus, it becomes hard to explain persistent inflammatory infiltrates that might occur in individuals affected with chronic myocarditis/DCM manifesting myocardial dysfunctions. In these circumstances, autoimmunity is suspected, and antibodies to various autoantigens have been demonstrated, suggesting that immune therapies to suppress the autoimmune responses may be necessary. From this perspective, we endeavoured to determine whether or not the known viral causes are associated with development of autoimmune responses to cardiac antigens that include both cardiotropic and non-cardiotropic viruses. If so, what their nature and significance are in developing chronic myocarditis resulting from viruses as primary triggers.

Viruses in the Heart: Direct and Indirect Routes to Myocarditis and Heart Failure

Viruses are an underappreciated cause of heart failure. Indeed, several types of viral infections carry cardiovascular risks. Understanding shared and unique mechanisms by which each virus compromises heart function is critical to inform on therapeutic interventions. This review describes how the key viruses known to lead to cardiac dysfunction operate. Both direct host-damaging mechanisms and indirect actions on the immune systems are discussed. As viral myocarditis is a key pathologic driver of heart failure in infected individuals, this review also highlights the role of cytokine storms and inflammation in virus-induced cardiomyopathy.

Coxsackievirus B heart infections and their putative contribution to sudden unexpected death: An 8-year review of patients and victims in the coastal region of Tunisia

Coxsackieviruses B (CV B) are known as the most common viral cause of human heart infections. Cardiac inflammations contribute to sudden unexpected death (SUD) significantly. The diagnosis remains difficult with the traditional diagnostic tests and must be substantially improved. This has prompted health professionals to seek new diagnostic procedures which may provide important clues regarding underlying etiology. The present study is based on patients with infectious heart diseases and SUD victims with no relevant pathologies. They were investigated for possible CV-B infection. Patients with coronary artery diseases and unnatural road and domestic accident victims served as controls. The samples were studied for CV-B applying PCR. Histopathology for inflammatory markers, immunohistochemistry (IHC) for immune inflammatory cells and the enteroviral VP1-capsid protein were performed. Overall, 102 patients and 87 SUD victims were studied. As controls, 100 patients and 54 SUD unnatural accident victims were enrolled. CV-B were detected in 28 patients and 15 SUD victims. The control group samples were completely virus negative. Compared to controls, IHC revealed a significant presence of T and B lymphocytes within the myocardium. Furthermore, enteroviral VP1-capsid protein were detected from samples by IHC. Applying a comprehensive combination of methods, our results demonstrate the involvement of CV-B in cases of heart infection suggesting they play a significant role in SUD. Our results emphasize the importance of opting for a combination of methods.

Postmortem diagnosis of infectious heart diseases: A mystifying cause of Sudden Infant Death

Sudden infant death (SID) is an unresolved problem of high relevance and previous studies have indicated a role of viral heart infections. The diagnosis remains difficult in clinical practice using routine diagnostic tests and must be substantially improved. A prospective study based on post-mortem samples from SID victims whose heart disease was not clinically recognized was conducted for 4 years in a Tunisian University Hospital. Pediatric cases of unnatural death served as controls. Both SID victims and controls were investigated for possible coxsackievirus-B (CV-B) infection in heart tissue. During the study period, 39 cases with a male predominance (77%) were reported. There was no positive family history of coronary artery disease among the victims. In 35 cases (90%), low birth weight and/or critical development period were reported. All SID victims had complained of mild fever and insomnia for a few days preceding death, which required infectious laboratory investigations marked with an elevated white blood cell count (WBC) and C-reactive protein (CRP). The cardiac biomarkers were also elevated. The histopathological investigations of the heart tissue samples revealed signs of myocardial and pericardial inflammation. Enterovirus was detected by immunohistochemistry (IHC) and PCR from myocardial samples from 6 cases (15.3%) having myocarditis and 3 cases (7.7%) having perimyocarditis. The current study is of great interest and is aimed at urging health professionals to adopt systematically long intensive heart care in infants with underlying vulnerability as well as new diagnostic approaches including histopathology complemented with IHC and molecular pathology.

Management of fulminant myocarditis: a diagnosis in search of its etiology but with therapeutic options

Fulminant myocarditis is a clinical syndrome with signs of acute heart failure, cardiogenic shock, or life-threating rhythm disturbances in the context of suspected myocarditis. It is not an etiological diagnosis, but may have different underlying causes and pathogenetic processes - viral, bacterial, toxic, and autoreactive. Clinical management of the disease entity at the acute stage involves hemodynamic monitoring in an intensive care unit or similar setting. Rapid routine work-up is mandatory with serial EKGs, echocardiography, cardiac MRI, heart catheterization with endomyocardial biopsy for histology, immunohistology, and molecular analysis for the underlying infection and pathogenesis. Heart failure therapy is warranted in all cases according to current guidelines. For fulminant autoreactive myocarditis, immunosuppressive treatment is beneficial; for viral myocarditis, IVIg can resolve the inflammation, reduce the viral load, and even eradicate the microbial agent. ECMO, IABP, ventricular assist devices, LifeVest, or ICD implantation can bridge to recovery or to heart transplantation.

Mortality in schizophrenia: clinical and serological predictors

Persons with schizophrenia have a reduced life expectancy largely due to death from natural causes. Factors that have been previously associated with excess mortality include cigarette smoking and antipsychotic medication. The role of other environmental factors such as exposure to infectious agents has been the subject of only limited investigation. We prospectively assessed a cohort of persons with schizophrenia with a clinical evaluation and a blood sample from which antibodies to human herpes viruses and Toxoplasma gondii were measured. Mortality was determined with data from the National Death Index following a period of up to 11 years. We examined the role of demographic, serological, and clinical factors on mortality. A total of 25 (5%) of 517 persons died of natural causes. The standardized mortality ratio was 2.80 (95% CI 0.89, 6.38). After adjusting for age and gender, mortality from natural causes was predicted in separate models by cigarette smoking (relative risk [RR] = 4.66, P = .0029); lower cognitive score (RR = 0.96, P = .013); level of antibodies to Epstein-Barr virus (RR = 1.22, P = .0041) and to Herpes Simplex virus type 1 (RR = 1.19, P = .030); immunologic disease (RR = 3.14, P = .044); and genitourinary disease (RR = 2.70; P = .035). Because cigarette smoking confers an almost 5-fold risk of mortality, smoking cessation is an urgent priority. Having an elevated level of antibodies to Epstein-Barr virus and to Herpes Simplex virus type 1 are also significant predictors of death from natural causes.

Repetitive fulminant influenza myocarditis requiring the use of circulatory assist devices

A 52-year-old man was admitted to our hospital due to shortness of breath that developed one week after the diagnosis of influenza infection. He had a past history of myocarditis associated with influenza B infection 16 years before the current admission. The patient's left ventricular function showed diffuse hypokinesis with a left ventricular ejection fraction of 28%. Due to the progression of heart failure, the infusion of catecholamines and insertion of an intra-aortic balloon pump were required. The patient was discharged uneventfully on the 23rd hospital day. A significant increase in the serum antibody titer against influenza A virus subtype H3N2 led to a diagnosis of recurrent fulminant influenza myocarditis.

Cardiac complications and immunophenotypic profile of infectious mononucleosis syndrome in children

OBJECTIVE

To investigate cardiac complications in infectious mononucleosis patients and to associate them with biochemical and immunological parameters, as well as with spleen ultrasound findings.

DESIGN

Cross-sectional study with follow-up.

SETTING

Tertiary care pediatric unit, in the city of Thessaloniki, Greece.

PARTICIPANTS AND INTERVENTIONS

Twenty-five children (15 boys, aged 1-11.6 years) suffering from infectious mononucleosis were studied during the acute phase and after 3-6 months. Cardiac evaluation comprised of electrocardiogram, echocardiogram, and measurement of creatine phosphokinase, creatine phosphokinase cardiac isoenzyme, and troponin levels. Biochemical and immunological tests included serum transaminases, serum amylase, CD3+/CD8+ T-lymphocytes subpopulation and CD4+/CD8+ T-lymphocytes ratio.

RESULTS

During acute phase, all children had splenomegaly and normal serum amylase values. 17 patients had elevated serum transaminases. Percentages of CD3+/CD8+ T-lymphocytes subpopulation were elevated and CD4+/CD8+ ratio was decreased in all patients. Echocardiography revealed mild pericardial effusion in 13 patients (10/21 with Epstein-Barr infection, 3/4 with cytomegalovirus infection), but none presented with myocarditis. Four out of these 13 patients also had markedly elevated liver enzymes, 10/13 had significant splenomegaly and 12/13 presented very low CD4+/CD8+ T-lymphocytes ratio. Pericardial effusion demonstrated a statistically significant association solely with very low CD4+/CD8+ T-lymphocytes ratio (<0.5). Repetition of laboratory tests 3-6 months post-discharge detected persistent mild pericardial effusion in five patients, along with decreased CD4+/CD8+ ratio in 1/5.

CONCLUSIONS

In infectious mononucleosis syndrome, asymptomatic pericardial effusion could be associated with very low CD4+/CD8+ ratio (<0.5). Further studies would extend and confirm such an association.

Epstein-Barr virus infection in pregnancy--a prospective controlled study

BACKGROUND

Epstein-Barr virus (EBV) is one of the most common human viruses. To date, there is limited information regarding the influence of maternal EBV infection on pregnancy outcome.

OBJECTIVE

Our aim was to examine the fetal safety of EBV infection in pregnancy.

STUDY DESIGN

We prospectively evaluated the rate of major anomalies and pregnancy outcome of women with serologic evidence of primary, recurrent or undefined infection (27, 56, and 43 women, respectively) compared to 1434 women who called the Israeli TIS for non-teratogenic exposure.

RESULTS

Women's characteristics and pregnancy outcome were comparable between the EBV exposed and control groups. Similarly, the gestational age at delivery and birth weight were not significantly different. The rate of major congenital anomalies did not significantly differ between the EBV exposed compared to the control group.

CONCLUSION

This study suggests that EBV infection during pregnancy does not represent a major teratogenic risk to the fetus.

Lymphocytic Myocarditis After Lung Transplantation

This study reports the development of lymphocytic myocarditis in a bilateral lung allograft recipient. A 23-year-old woman developed congestive heart failure and severe left ventricular dysfunction 32 months after a bilateral lung allograft for cystic fibrosis. She had taken oral acyclovir for infectious mononucleosis that was diagnosed 11 months previously. Her viral load for Epstein-Barr virus (EBV) increased, and an echocardiogram revealed a left ventricular ejection fraction of 25% and endomyocardial biopsy revealed lymphocytic myocarditis. She received valacyclovir (1 g x 3 times daily) and made a full recovery 6 months later.

Epstein–Barr virus myocarditis as a cause of sudden death: two autopsy cases

Although the Epstein-Barr virus (EBV) causes acute infection accompanied by a high fever in young people, there appears to be few reports of a fatal outcome involving myocarditis. We report two cases of unexpected sudden death due to acute myocarditis possibly caused by the EBV. They each visited a hospital due to common cold-like symptoms and unexpectedly died several days later. In both cases, autopsy revealed myocardial necrosis with marked lymphocytic infiltration. Polymerase chain reaction (PCR) screening was positive for the EBV, whereas immunohistochemistry and in situ hybridization for the EBV were negative. Serological investigations showed a mild elevation in antiviral capsid antigen IgG and anti-EBV nuclear antigen IgG in both cases. Immunohistochemical study of lymphocytic infiltrates showed strong positivity for a T-cell marker (CD45R0) in the myocardium and pharyngeal mucosa. These cases suggest the potential risk of mortality from acute EBV infection in young people, even without severe clinical manifestations, and the importance of microbiological investigations, including PCR procedures, in postmortem diagnosis of infectious diseases.

Role of virus-induced myocardial affections in sudden infant death syndrome: a prospective postmortem study

The cause of sudden infant death syndrome (SIDS) is an unresolved problem of high relevance. Previous studies indicate a role of infections. In our prospective study, we investigated the frequency of virus-induced myocardial affections in SIDS. Postmortem samples from SIDS victims and control subjects were investigated prospectively. Pediatric cases of unnatural death served as controls. Samples were studied for enteroviruses, adenoviruses, parvovirus B19, and Epstein-Barr virus applying PCR. Immunohistochemical investigations for inflammatory cells, the necrosis marker C5b-9((m)) complement complex, and the enteroviral capsid protein VP1 were performed. Overall, 62 SIDS victims were studied. As controls, 11 infants were enrolled. Enteroviruses were detected in 14 (22.5%), adenoviruses in 2 (3.2%), Epstein-Barr viruses in 3 (4.8%), and parvovirus B19 in 7 (11.2%) cases of SIDS. Control group samples were completely virus negative. Compared with controls, immunohistochemical investigations partially revealed a significant increase in the number of T lymphocytes in SIDS myocardial samples (p < 0.05). Furthermore, cases with elevated numbers of leukocytes and macrophages, microfocal C5b-9((m))(+) necroses, and enteroviral VP1 capsid protein within the myocardium were detected. Applying a comprehensive combination of molecular and immunohistochemical techniques, our results demonstrate a clearly higher prevalence of viral myocardial affections in SIDS. Our results emphasize the importance of PCR-based diagnosis of viral myocardial affections. We suggest preliminary criteria for cellular immunohistochemical diagnosis of viral myocardial affections derived from our findings. For future investigations in SIDS, we suggest a comprehensive approach that includes PCR and immunohistochemistry. Our results offer novel strategies for diagnosis of pediatric myocardial viral affections.

Molecular pathology of inflammatory cardiomyopathy

Endomyocardial biopsy (EMB) is often performed in patients presenting with sudden onset of heart failure to identify myocarditis. The introduction of immunohistochemical techniques for the detection and differentiation of infiltrating immune cells, specific adhesion molecules and MHC class I and II molecules increased the prognostic value of EMB in the diagnosis of myocarditis considerably. A major breakthrough in the understanding of pathogenetic mechanisms in myocarditis was achieved by diagnostic use of molecular biological methods. By application of in situ hybridization and PCR, enteroviruses, and more recently, parvovirus B19 (PVB19) have been identified as relevant agents of myocarditis. The different cell tropism of these viruses implicates distinct pathogenic principles, which, at present, are not completely understood. Whereas enteroviruses damage the heart primarily via direct lysis of infected myocytes, PVB19 does not infect myocytes, but endothelial cells of small intracardiac arterioles and venules, resulting in impairment of myocardial microcirculation with secondary myocyte necrosis during acute infection. Histological and immunohistological stainings combined with molecular biological approaches in EMB will help us to resolve the question of whether patients with myocarditis should be treated by specific antiviral agents or by immunosuppressive therapies.

Molecular diagnosis of myocarditis and dilated cardiomyopathy in children: clinicopathologic features and prognostic implications

Myocarditis is the most common cause of heart failure in children. We investigated viral etiology of myocarditis/dilated cardiomyopathy (DCM) in children and correlated molecular findings with pathologic and clinical data. Polymerase chain reaction (PCR) or reverse transcription (RT)-PCR were used to analyze 59 endomyocardial biopsies from 48 consecutive young (<18 yrs) patients (pts) with clinical and histologic diagnosis of myocarditis and DCM, employing primers designed to amplify specific sequences of various DNA and RNA viruses. Nucleic acids were successfully extracted in 41 pts and viral genomes were found in 20 (49%): 12 out of 26 pts (46%) with myocarditis, 6 out of 13 (46%) pts with DCM, and both patients with endocardial fibroelastosis. Enteroviruses were more common in DCM (72%), whereas adenoviruses and enteroviruses shared the same rate (36%) in myocarditis. The mumps virus genome was detected in the two pts with endocardial fibroelastosis. More diffuse inflammatory infiltrates and myocyte damage as well as more impaired left ventricular end diastolic volume and shortening fraction were noted in viral positive cases. PCR positive pts had a worse outcome, resulting in transplantation or death. Three out of 8 pts with viral myocarditis who underwent cardiac transplantation had recurrent PCR-proven graft viral infection. Viral myocarditis/DCM appeared to be a more severe disease than nonviral forms. Enteroviruses were more common in DCM, whereas adenoviruses were as frequent as enteroviruses in myocarditis. Persistence of viral infection was associated with disease deterioration. Viral myocarditis relapsed after transplantation.

A rare presentation of childhood pompe disease: cardiac involvement provoked by Epstein-Barr virus infection

Myocarditis attributed to Epstein-Barr virus (EBV) as the sole cause is a rare manifestation. Myocarditis ascribed to EBV infection in combination with other factors has been reported in a few more cases. We report a child who experienced active EBV infection and later, at 19 months of age, received a diagnosis of Pompe disease (acid alpha-glucosidase deficiency) with predominant cardiac involvement. The cardiac symptoms resolved at the end of the EBV infection. When the patient was recently seen, at 8 years of age, she had an increased left ventricular wall thickness but normal cardiac function. DNA analysis identified this patient as compound heterozygote for a mutant Tyr292Cys and a null allele. In light of genotype-phenotype correlation, it is notable that a Spanish patient with a functionally similar genotype (Tyr292Cys/Arg854Stop) also had childhood Pompe disease with peripheral muscular involvement.

Active versus borderline myocarditis: clinicopathological correlates and prognostic implications

OBJECTIVE

To compare active (AM) with borderline (BM) myocarditis to verify whether the pathological distinction between the two forms may help to identify patients with different clinical and haemodynamic characteristics and to aid prognosis.

MATERIALS

Myocarditis was diagnosed in 56 patients on endomyocardial biopsy (EMB) within one year from clinical onset of the disease between 1991 and 1998. Fourteen patients were excluded because of a lack of adequate and complete information. EMBs and clinical records of the 42 remaining patients were reviewed. Immunohistochemistry on bioptic samples was regularly performed. Polymerase chain reaction (PCR) for a panel of viruses was performed in 23 patients (55%). Clinicopathological correlations were calculated.

RESULTS

The histological diagnosis was AM in 26 patients (62%) and BM in 16 (38%). Significant differences were found in the following parameters: presence of left bundle branch block on ECG (AM 2 (8%) v BM 5 (31%), p = 0.05); left ventricular volume on echocardiogram (mean (SD) AM 90 (42) ml/m(2) v BM 128 (50) ml/m(2), p = 0.002); mass to volume ratio (AM 1.0 (0) v BM 0.8 (0.1), p = 0.03); time interval between clinical onset of the disease and EMB (AM 40 (55) v BM 90 (93) days, p = 0.04); and degree of inflammatory infiltrates, scored on a scale of 0 to 3 (AM 1.65 (0.8) v BM 0.85 (0.3), p = 0.004). In 6 of 15 patients (40%) with AM and in 2 of 8 (25%) with BM, a viral genome was detected by PCR (NS). At follow up, no differences in death or heart transplantation were detected between the two forms (AM 4 patients (15%) v BM 2 patients (12.5%)). Three of eight PCR positive patients (37.5%) and 1 of 15 virus negative patients (7%) died or underwent heart transplantation.

CONCLUSIONS

BM seems to encompass inflammatory forms with a less aggressive inflammatory infiltrate evolving towards left ventricular dilatation. The term "chronic myocarditis" seems to be more appropriate. The absence of myocyte necrosis does not predict a more favourable prognosis, whereas the absence of a viral genome seems to predict it.

Inflammatory left ventricular microaneurysms as a cause of apparently idiopathic ventricular tachyarrhythmias

BACKGROUND

We sought to investigate the arrhythmogenic role, incidence, treatment, and prognosis of inflammatory left ventricular (LV) microaneurysms in patients with apparently idiopathic ventricular tachyarrhythmias. Methods and Results-- We studied 156 consecutive patients (71 men, 85 women; mean age, 44.1+/-11.8 years) with severe ventricular arrhythmias and normal 2D echo cardiac parameters by coronary and ventricular angiography, biventricular endomyocardial biopsy, and electrophysiological study. Polymerase chain reaction was used to detect genomic sequences of enterovirus, adenovirus, Epstein Barr virus, cytomegalovirus, herpes simplex viruses, influenza A and B viruses, and hepatitis C virus in frozen endomyocardial samples. Of these patients, 15 (9.6%) showed angiographic evidence of single or multiple LV microaneurysms. All 15 patients had recurrent episodes of ventricular tachycardia with right bundle-branch block morphology, and the arrhythmias originated within or close to the aneurysms in those patients (n=6) undergoing ventricular mapping. A lymphocytic myocarditis was observed in LV biopsies of all patients and in the right ventricles of 3 patients. Polymerase chain reaction analysis was performed in 12 and viral genomes were found in 5 (42%): hepatitis C virus in 2, enterovirus in 2, and influenza virus A in 1. The patients were treated with antiarrhythmics, and cardiac function was preserved for the next 47+/-39.5 months of follow-up. No major clinical event was registered, and arrhythmias were successfully treated by antiarrhythmics.

CONCLUSIONS

Inflammatory LV microaneurysms, often of viral origin, are a consistent cause of apparently idiopathic ventricular arrhythmias. Their prognosis so far has been benign, and aggressive therapeutic strategies have been unnecessary.

Fatal atypical T-cell proliferation associated with Epstein-Barr virus infection

We report the case of a young Caucasian man who presented with polyneuropathy and severe, ultimately fatal, congestive heart failure in the context of a chronic active Epstein-Barr virus (EBV) infection. Post-mortem examination revealed both monoclonal and polyclonal proliferation of EBV-positive atypical T lymphocytes within different organs. Predominant infiltration of the nervous system and heart with extensive myocardial scarring accounted for the clinical symptoms. The remarkable features of this case are (i) the occurrence in a Caucasian patient, (ii) the absence of detectable immunodeficiency, and (iii) the myocardial destruction by EBV-infected monoclonal T cells.

Myocarditis mimicking acute myocardial infarction: role of endomyocardial biopsy in the differential diagnosis

OBJECTIVE

To test the hypothesis, using endomyocardial biopsies, that unexplained cases of apparent acute myocardial infarction were caused by myocarditis.

MATERIAL

Between 1992 and 1998, 12 patients were admitted to the coronary care unit with severe chest pain, ST segment elevation, increased serum creatine kinase and MB isoenzyme, and with wall motion abnormalities on echocardiogram highly suggestive of acute myocardial infarction. These patients were further investigated by endomyocardial biopsy, as their coronary angiograms were normal. A diagnosis of myocarditis was made according to the Dallas criteria. A panel of antibodies was used for immunohistochemical characterisation of inflammatory cell infiltrate. Polymerase chain reaction (PCR) was used to detect viral genomes in seven cases.

RESULTS

Haematoxylin and eosin staining of the endomyocardial biopsy showed active myocarditis in six patients and borderline myocarditis in one. Immunohistochemistry was positive for inflammatory cell infiltrates in 11 patients, including all the seven who were positive on haematoxylin and eosin staining according to the Dallas criteria. Only one patient had no evidence of inflammation. PCR was positive in two patients, both for Epstein-Barr virus. Follow up showed complete resolution of echocardiographic abnormalities in all patients except one.

CONCLUSIONS

Myocarditis can mimic acute myocardial infarction in patients with angiographically normal coronary arteries, leading to errors of treatment. In patients with apparent myocardial infarction and a normal coronary angiogram, endomyocardial biopsy may help in the diagnosis of myocarditis. The sensitivity of endomyocardial biopsy was enhanced by using immunohistochemical and molecular biological techniques.