Sudden cardiac death in a 5-year-old girl associated with parvovirus B19 infection

Metagenomic analysis of viral genes integrated in whole genome sequencing data of Thai patients with Brugada syndrome

Brugada syndrome (BS) is an autosomal dominant inheritance cardiac arrhythmia disorder associated with sudden death in young adults. Thailand has the highest prevalence of BS worldwide, and over 60% of patients with BS still have unclear disease etiology. Here, we performeda new viral metagenome analysis pipeline called VIRIN and validated it with whole genome sequencing (WGS) data of HeLa cell lines and hepatocellular carcinoma. Then the VIRIN pipelinewas applied to identify viral integration positions from unmapped WGS data of Thai males, including 100 BS patients (case) and 100 controls. Even though the sample preparation had noviral enrichment step, we can identify several virus genes from our analysis pipeline. The predominance of human endogenous retrovirus K (HERV-K) viruses was found in both cases andcontrols by blastn and blastx analysis. This study is the first report on the full-length HERV-Kassembled genomes in the Thai population. Furthermore, the HERV-K integration breakpointpositions were validated and compared between the case and control datasets. Interestingly,Brugada cases contained HERV-K integration breakpoints at promoters five times more oftenthan controls. Overall, the highlight of this study is the BS-specific HERV-K breakpoint positionsthat were found at the gene coding region "NBPF11" (n = 9), "NBPF12" (n = 8) and longnon-coding RNA (lncRNA) "PCAT14" (n = 4) region. The genes and the lncRNA have been reported to be associated with congenital heart and arterial diseases. These findings provide another aspect of the BS etiology associated with viral genome integrations within the humangenome.

Parvovirus B19-Associated Myocarditis: A Literature Review of Pediatric Cases

Parvovirus B19 (B19V) infection may lead to myocarditis, a life-threatening condition in pediatric patients. In this review, we aim to present published pediatric cases of B19V-associated myocarditis in order to understand the deep complex connections and draw useful conclusions. We performed a comprehensive search of MEDLINE, Science Direct, and Google Scholar electronic databases. A total of 32 cases were included in our study. The most common presenting symptom was tachycardia in 22/32 patients (68.7%), followed by tachypnoea (21/32, 65.6%), fever, and rash (12/32, 37.5% for both of them). Cardiac arrest, loss of consciousness, and systemic infection were associated with the worst prognosis, with statistically significant differences (p-value 0.001, 0.02, 0.001. respectively). A percentage as high as 90.4% of patients with left ventricular (LV) dysfunction and reduced ejection fraction (EF) were discharged. Twelve patients required ventilatory support, five required extracorporeal membrane oxygenation (ECMO), and three underwent heart surgery. Treatment with immunosuppressive agents and immunoglobulin was found to be beneficial for patients (p-value 0.006 and 0.004, respectively). In conclusion, B19V myocarditis has high mortality rates in children. There is no specific antiviral treatment for B19V infection and therapeutic strategies for myocarditis aim to delay the worsening of heart failure and to preserve the LV function. Inotropic drugs, diuresis, ventilatory support, Intravenous immunoglobulin (IVIG), and immunosuppressive therapy seem to help the recovery of the myocardium in children with LV dilation, dysfunction, and reduced EF. Children with cardiac arrest, arrhythmias, and loss of consciousness have the worst prognosis.

A systematic review exploring the relationship between infection and sudden unexpected death between 2000 and 2016: A forensic perspective

Death due to infectious diseases is a major health concern worldwide. This is of particular concern in developing countries where poor-socio economic status and a lack of healthcare resources contribute to the high burden of disease. In some cases death due to infection can be acute and aggressive, and death may occur without a diagnosis whilst the person is still alive. These deaths may ultimately lead to a medico-legal autopsy being performed. There are various mechanisms by which sudden death due to infection may occur. In addition, there are many risk factors associated with sudden death due to infection, which differ between infants and older individuals. However, it is unclear which pathogens and risk factors are most frequently associated with sudden death due to infection. Therefore a systematic review of articles and case reports published between 1 January 2000 and 30 June 2016 was undertaken in order to (1) explore the relationship between pathogens and their causative role and (2) identify the relationship between predisposing and/or risk factors associated with sudden death due to infection. Major databases were searched and after critical appraisal 143 articles were identified. It was found that respiratory infections and deaths involving bacterial pathogens were most commonly associated with these deaths. In addition the most common risk factors in infants were exposure to tobacco smoke and co-sleeping. In adults the most common risk factors were co-morbid conditions and illnesses. This information aids in a better understanding of these deaths and highlights the need for more research in this field, particularly in developing countries.

Successful immunotherapy in life-threatening parvovirus B19 infection in a child

We report a case of an immunocompetent child who developed parvovirus B19 infection complicated by autoinflammatory disease with myocarditis, tamponade and macrophage activation syndrome. He recovered with immunotherapy including prednisone, immunoglobulins, cyclosporin and anakinra (anti-interleukin-1). The report shows that parvovirus can provoke severe systemic inflammation with acute heart injury and that anti-interleukin-1 might be considered in such parvovirus-related inflammation.

Parvovirus B19 Achievements and Challenges

Parvovirus B19 is a widespread human pathogenic virus, member of the Erythrovirus genus in the Parvoviridae family. Infection can be associated with an ample range of pathologies and clinical manifestations, whose characteristics and outcomes depend on the interplay between the pathogenetic potential of the virus, its adaptation to different cellular environments, and the physiological and immune status of the infected individuals. The scope of this review is the advances in knowledge on the biological characteristics of the virus and of virus-host relationships; in particular, the interactions of the virus with different cellular environments in terms of tropism and ability to achieve a productive replicative cycle, or, on the contrary, to establish persistence; the consequences of infection in terms of interference with the cell physiology; the process of recognition of the virus by the innate or adaptive immune system, hence the role of the immune system in controlling the infection or in the development of clinical manifestations. Linked to these issues is the continuous effort to develop better diagnostic algorithms and methods and the need for development of prophylactic and therapeutic options for B19V infections.

Sudden unexpected death related to enterovirus myocarditis: histopathology, immunohistochemistry and molecular pathology diagnosis at post-mortem

BACKGROUND

Viral myocarditis is a major cause of sudden unexpected death in children and young adults. Until recently, coxsackievirus B3 (CVB3) has been the most commonly implicated virus in myocarditis. At present, no standard diagnosis is generally accepted due to the insensitivity of traditional diagnostic tests. This has prompted health professionals to seek new diagnostic approaches, which resulted in the emergence of new molecular pathological tests and a more detailed immunohistochemical and histopathological analysis. When supplemented with immunohistochemistry and molecular pathology, conventional histopathology may provide important clues regarding myocarditis underlying etiology.

METHODS

This study is based on post-mortem samples from sudden unexpected death victims and controls who were investigated prospectively. Immunohistochemical investigations for the detection of the enteroviral capsid protein VP1 and the characterization and quantification of myocardial inflammatory reactions as well as molecular pathological methods for enteroviral genome detection were performed.

RESULTS

Overall, 48 sudden unexpected death victims were enrolled. As for controls, 37 cases of unnatural traffic accident victims were studied. Enterovirus was detected in 6 sudden unexpected death cases (12.5 %). The control samples were completely enterovirus negative. Furthermore, the enteroviral capsid protein VP1 in the myocardium was detected in enterovirus-positive cases revealed by means of reverse transcriptase-polymerase chain reaction (RT-PCR). Unlike control samples, immunohistochemical investigations showed a significant presence of T and B lymphocytes in sudden unexpected death victims.

CONCLUSIONS

Our findings demonstrate clearly a higher prevalence of viral myocarditis in cases of sudden unexpected death compared to control subjects, suggesting that coxsackie B enterovirus may contribute to myocarditis pathogenesis significantly.

Fatal parvovirus B19 myocarditis in children and possible dysimmune mechanism

We report 2 cases of previously healthy children, who developed, after a common parvovirus B19 infection, a sudden inflammatory response, involving predominantly T cell, directed against myocardium and leading to fatal outcome. These cases and several published case reports further our understanding of fulminating parvovirus myocarditis in children.

Childhood myocarditis and parvovirus B19 genotypes

BACKGROUND

Human parvovirus B19 (PVB19) infection is occasionally associated with acute myocarditis. Three cases of children with PVB19 virus-associated myocarditis occurred in a very short period and the same geographical region.

OBJECTIVE

To elucidate if virological factors could be responsible for determining the course of infection, a molecular epidemiologic investigation was performed.

STUDY DESIGN

The diagnosis of myocarditis was established by histology or echocardiography. In the three cases, the PVB19 DNA was detected in different samples. Eight different regions were amplified by PCR using a high fidelity Taq polymerase and sequenced on both strands. Phylogenetic analyses were performed. First, the genotypes of the PVB19 strains were determined, then the intra-patient viral variability was analysed by sequencing PVB19 detected in different specimens sampled from the same patient at the same moment.

RESULTS

Nearly complete sequences of the PVB19 virus (4265nt) were obtained from different samples in the three patients. The phylogenetic analyses showed that PVB19 strains identified clustered with genotype 1a PVB19 strains referenced in GenBank. When compared to the referenced strain NC_000883, the number of substitutions (transitions and transversions) were as follows: 58 for Caen.FRA/19.09, 74 for Caen.FRA/21.09 and 60 for Caen.FRA/24.09. The strains isolated from the same patient showed 100% of similarity.

CONCLUSIONS

Viral myocarditis is a frequently unrecognized cause of post-inflammatory cardiomyopathy. The detailed molecular analyses do not give rise to virological markers associated with myocarditis in these children.

First report of sudden death due to myocarditis caused by adenovirus serotype 3

Myocarditis is a rare cause of sudden death in childhood. We describe the sudden death of a child from viral myocarditis, which we demonstrate was likely caused by an uncontrolled inflammatory response to a disseminated adenovirus serotype 3 infection originating in the tonsil.

Fulminant parvovirus B19-associated pancarditis with haemophagocytic lympho-histiocytosis in an immunocompetent adult

Myocarditis is a common cardiac disease that is identified on routine postmortem examinations. Initially, coxsackie viruses, other enteroviruses and adenoviruses were thought to be more common causes of myocarditis; however, recently, parvovirus B19 (PVB19) as well as human herpesvirus 6 (HHV6) have entered the arena. We describe autopsy findings of a patient who had a lethal myocarditis with haemophagocytic lympho-histiocytosis in a course of systemic PVB19 infection. The present case illustrates the unusually severe and rapid course of PVB19 myocarditis with associated haemophagocytic lympho-histiocytosis leading to death.