Detection of Human Herpesvirus 6 DNA in Clinical Samples of Patients by Polymerase Chain Reaction Amplification

Abstract

SummaryThe detection of human herpesvirus 6 (HHV-6) DNA in peripheral blood mononuclear cells (PBMC), throat swabs, and cerebrospinal fluid (CSF) was determined using the polymerase chain reaction (PCR). The clinical samples were collected from patients with exanthem subitum (ES) during the acute and convalescent phases of infection, and from healthy children and adults. HHV-6 DNA was detected in mononuclear cells which were collected from ES patients during both acute and convalescent phases, and even from healthy adults. Mononuclear cells of peripheral blood were then separated into adherent and nonadherent cells. While DNA could be detected in nonadherent and adherent mononuclear cells during the acute phase, it was detected predominantly in adherent cells during convalescent phase. Furthermore, viral DNA was found in adherent cells of healthy adults. HHV-6 DNA could also be detected in throat swabs from children and adults having antibody to HHV-6. HHV-6 DNA was detected in CSF of ES patients who had some neurological symptoms at a high frequency. However, there was no detection of HHV-6 DNA in samples from neonates.Finally, we have developed nested double PCR, which could detect HHV-6 DNA more sensitively. A few copies of HHV-6 DNA could be detected by this method, even in clinical samples.