Detection of human herpesvirus 6 by reverse transcription-PCR

The role of human herpesvirus 6 (HHV-6) in disease beyond primary infection remains unclear, We have developed and validated a new reverse transcripti on-PCR (RT-PCR) assay for HHV-6 that can determine the presence of HHV-6 in clinical specimens and differentiate between latent and replicating virus. Peripheral blood mononuclear cells from 109 children were evaluated for HH V-6 by RT-PCR, DNA PCR, and viral culture, Of these samples, 106 were suita ble for analysis, A total of 20 samples were positive for HHV-6 by culture and DNA PCR, of which 19 were positive by RT-PCR (sensitivity, 95%). All 28 samples from children that were negative by viral culture, but positive by DNA PCR, were negative for viral transcripts by our RT-PCR assay. One posi tive RT-PCR result was observed in 56 samples that were negative by tissue culture and DNA PCR This indicates a low rate of false-positive results (1. 2%) and a specificity of 98.8%, This RT-PCR assay can reliably differentiat e between latent and actively replicating HHV-6 and should allow insight in to the pathogenesis of this ubiquitous virus.