Parvovirus B19: the causative agent of dilated cardiomyopathy or a harmless passenger of the human myocard?

Association of parvovirus B19 and myocarditis/dilated cardiomyopathy: A systematic review and meta-analysis

BACKGROUND

The potential association between Parvovirus B19 and heart disease has been controversial. The aim of the present study was to report the prevalence of B19 in myocarditis and dilated cardiomyopathy (DCM) as well as measure the statistical association between them.

METHODS

Our systematic search was carried out to retrieve published articles between January 2000 and March 2021 using three major databases: PubMed, Scopus, and Web of Science, as well as the Google Scholar search engine. The overall prevalence of HAV, pooled odds ratio, and heterogeneity were estimated by comprehensive meta-analysis (V2.2, Biostat) software.

RESULTS

The overall prevalence results in myocarditis and DCM were 23.7% (95% CI: 18.7%-29.5%) and 34.1% (95% CI: 23.8%-46.1%) respectively; in addition, the overall OR for B19 and myocarditis was 4.317 (95% CI, 1.831-10.180) versus 1.163 (95% CI: 0.706-1.916) for B19 and DCM.

CONCLUSION

Our findings have shown a significant association between Parvovirus B19 and myocarditis with a high prevalence. In the case of DCM, no significant association was found while the prevalence of the virus was relatively high.

Systematic Review of PCR Proof of Parvovirus B19 Genomes in Endomyocardial Biopsies of Patients Presenting with Myocarditis or Dilated Cardiomyopathy

Background: Diverse viral infections have been associated with myocarditis (MC) and dilated cardiomyopathy (DCM). In this meta-analysis, we summarize the published results on the association of parvovirus B19 (B19V) genomes with human MC/DCM versus controls. Methods: n = 197 publications referring to B19V and MC or DCM were retrieved using multiple PubMed search modes. Out of these, n = 29 publications met the inclusion criteria with data from prospective analyses on >10 unselected patients presenting with MC or DCM (dataset: MA01). Data retrieved simultaneously from both controls and MC/DCM patients were available from n = 8 from these publications (dataset: MA02). Results: In the dataset MA01 B19V genomes were detected in 42.6% of the endomyocardial biopsies (EMB) in this cohort by PCR. In the dataset MA02 comprising n = 638 subjects, there was no statistically significant different rate of B19V positivity in myocardial tissues comparing controls (mean: 38.8 + 24.1%) versus the MC/DCM-patients (45.5 + 24.3%; p = 0.58). There was also no statistical difference between the positivity rate of B19V genomes in myocardial tissues of MA01 (46.0 + 19.5%) and the two patient groups of MA02 (p > 0.05). Conclusions: This systematic review reveals that the mean rate of PCR detected B19V genomes in patients presenting with MC/DCM does not differ significantly from the findings in control myocardial tissues. These data imply pathogenetically insignificant latency of B19V genomes in a proportion of myocardial tissues, both in MC-/DCM-patients and in controls. More information (i.e., replicative status, viral protein expression) is pertinent to achieve a comprehensive workup of myocardial B19V infection.

Evolutionary aspects of Parvovirus B-19V associated diseases and their pathogenesis patterns with an emphasis on vaccine development

Parvovirus B-19, a single human pathogenic member of the Parvoviridae family with it's small ssDNA and non-enveloped structure, is known to cause diseases in erythroid progenitor cells. But a wide range of clinical association of this virus with cells of non-erythroid origins has recently been discovered and many of those are being investigated for such association. Higher substitution rates in due course of evolution has been suggested for this cellular tropism and persistence. In this report, we have summarized the different disease manifestations of B-19 virus and have tried to find out a pattern of pathogenesis. Finally, we have focused on the vaccination strategies available against B-19 virus to correlate these with the mechanisms involved in various diseases caused by this virus.

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.

Persistent adeno-associated virus 2 and parvovirus B19 sequences in post-mortem human cerebellum

We previously reported in a large cohort (N = 104) of post-mortem tissues the detection of both the non-pathogenic adeno-associated virus (AAV2) in approximately 13% and the pathogenic human parvovirus B19 (B19) in approximately 42% of human brains, particularly the dorsolateral prefrontal cortex. Multiple animal parvoviruses target the developing cerebellum (CBLM) resulting in hypoplasia and ataxia, but very little is known about the human parvoviruses and their ability to infect or cause disease in the CBLM. We have now confirmed in the above cohort the presence of AAV2 and B19 sequences in the CBLM. Our results show that approximately 27% and approximately 70% of human CBLM are positive by nested polymerase chain reaction for AAV2 and B19 sequences, respectively. We also document in a second cohort (N = 10) the presence of AAV2 (50%) and B19 (100%) sequences in the CBLM and correlate our results for B19 with studies from matched sera. Eighty percent (80%) of this cohort was positive for anti-B19 IgG, while none were IgM+, suggesting that most individuals had been previously infected with B19 but none acutely. To our knowledge, this study is the first to demonstrate that both AAV2 and B19 sequences are present at relatively high frequencies in the CBLM and are likely due to persistent rather than acute infection. Further studies will lead to insights into AAV2- and/or B19-CBLM interactions including mechanisms of infection, persistence, and possibly neuropathology, including cerebellar hypoplasia and ataxia.

Blood donor screening for parvovirus B19 in Germany and Austria

BACKGROUND

Although the main transmission pathway of parvovirus B19 (B19) is typically via the respiratory route, several transfusion-transmitted infections have been reported. To increase blood safety, all blood donations to our blood donor service have been screened by a B19 minipool real-time nucleic acid testing (NAT) since April 2000. Additional customers have been screened since the summer of 2003.

STUDY DESIGN AND METHODS

In total, 2.8 million donations from Germany and Austria were screened for B19 by real-time minipool NAT. A subgroup of 50 B19 DNA-positive donors was screened for B19 immunoglobulin G (IgG) and IgM antibodies and B19 DNA over a 6-month period. Results were compared to those of 100 B19 DNA-negative donors.

RESULTS

Data accumulated over the past 6 years indicate a high incidence period from May 2004 to January 2006. In total, the incidence was 12.7 and 261.5 per 100,000 donations with high virus loads equal to or above 10(5) and below 10(5) IU per mL, respectively. Median virus concentration in the case group was 4.85 x 10(7) IU per mL at Time Point T0 and was reduced to 4 x 10(2) IU per mL at the time of the next donation (3 months later). Neutralizing antibodies (VP2) were detected in all donations if virus load was reduced to less than 10(5) IU per mL.

CONCLUSION

The release of B19 DNA-positive blood products with a concentration of less than 105 IU per mL is thought to be safe due to the high level of neutralizing VP2 antibodies and is currently examined in a donor recipient infectivity study. In contrast, blood products with a high B19 DNA concentration (> or =10(5) IU/mL), some of which did not contain neutralizing antibodies, were discarded to protect at risk individuals.