Parvovirus B19 profiles in patients presenting with acute myocarditis and chronic dilated cardiomyopathy

Background: Parvovirus B19 (B19V) is the most prevalent cardiotropic virus in endomyocardial biopsies (EMBs) from patients presenting with acute myocarditis (AMC) and chronic dilated cardiomyopathy (DCM). We elucidated the role of B19V specific IgG and IgM antibodies against native VP2-capsids and denatured VP1-, VP2- and NS1-proteins, which discriminate disease acuity in other B19V related diseases, in patients presenting with clinically suspected AMC and DCM for the determination of the viral infection stage.
Material and Method: n=62 prospectively enrolled AMC (n=33) and DCM (n=29) patients were investigated. B19V genomes were amplified in EMBs by nested PCR (nPCR). B19V-specific IgG and IgM were investigated by recomLine blots in the sera.
Results: B19V genomes were detectable by nPCR with comparable frequencies in AMC (63.6%) and DCM patients (51.7%), respectively. IgM antibodies were detectable in 18.1% of the AMC, but not in DCM patients. In patients with myocardial B19V infection, antibody profiles indicating recent infections were more frequent in AMC (47.6%) compared with DCM patients (6.7%), while persistent/reactivating profiles were significantly more prevalent in DCM (20.0%) compared with AMC (0%) patients (p<0.05).
Conclusions: IgM B19V antibodies can be detected primarily in AMC, but not in DCM patients. The discrimination of the B19V specific IgG antibodies using recomLine blots may be suitable to distinguish acute versus chronic, and persistent/reactivating infection status in patients with myocardial B19V infection.

Keywords: Parvovirus B19, Human - isolation & purification, Prospective Studies, Polymerase Chain Reaction, Parvoviridae Infections - virology, Myocarditis - virology, DNA, Viral - blood, Chronic Disease, Case-Control Studies, Cardiomyopathy, Dilated - virology, Antibodies, Viral - blood, Adult, Acute Disease