26433 Human Herpesvirus-6, Molecular Detection, PCR, Plasma (HHV6)

Exanthem Subitum

Herpes Virus-6

HHV-6 (Human Herpes Virus-6)

Human Herpes Virus-6 (HHV-6)

Roseola Infantum

​As an adjunct in the rapid diagnosis of human herpesvirus-6 infection in plasma specimens

​Spin down promptly.

Gross hemolysis

​The sensitivity of the assay is very dependent upon the quality of the specimen submitted.

A negative test does not exclude infection with human herpesvirus-6 (HHV-6) virus. Therefore, the results obtained should be used in conjunction with clinical findings to make an accurate diagnosis.

This assay detects nucleic acid, and therefore, cannot distinguish between viable and nonviable virus. Test performance depends on viral load in the specimen and may not correlate with cell culture performed on the same specimen.

Herpesvirus-6 (HHV-6) is a member of the Herpesviridae family. These viruses contain DNA surrounded by a lipid envelope. Among members of this group, this virus is most closely related to cytomegalovirus (CMV) and HHV-7. As with other members of the herpesvirus group (herpes simplex virus [HSV] 1, HSV 2, varicella zoster virus [VZV], CMV, Epstein-Barr virus [EBV], HHV-7, HHV-8), HHV-6 may cause primary and reactivated infections subsequent to latent association with cells. Infection with HHV-6 occurs early in childhood. Most adults (80%-90%) have been infected with this virus.

HHV-6 was first linked with exanthem subitum (roseola infantum) in 1998; since then, the virus has been associated with central nervous system disease almost exclusively in immunocompromised patients.(1) HHV-6 is commonly detected in patients posttransplantation. Clinical symptoms associated with this viral infection include febrile illness, pneumonitis, hepatitis, encephalitis, and bone marrow suppression. However, the majority of HHV-6 infections are asymptomatic. The incidence of HHV-7 infection and its clinical manifestations posttransplantation are less well characterized.

HHV-6 is designated as variant A (HHV-6A) or variant B (HH6-B) depending on restriction enzyme digestion patterns and on its reaction with monoclonal antibodies. Generally, variant B has been associated with exanthem subitum, whereas variant A has been found in many immunosuppressed patients.

A positive result indicates the presence of specific DNA from human herpesvirus-6 (HHV-6) and supports the diagnosis of infection with this virus.

A negative result indicates the absence of detectable DNA from HHV-6 in the specimen, but it does not negate the presence of the virus or active or recent disease.