The mechanism, diagnosis and treatment of HHV-6B encephalitis

Human herpesvirus 6B (HHV-6B) is causative agent for exanthem subitum, which is common febrile illness in infant. This disease is generally benign and self-limited disease, however rarely causes several central nervous system complications. As various types of HHV-6B encephalitis has been demonstrated, pathophysiology of the disease would be complicate. Thus, different therapeutic strategies should be established for each type of HHV-6B encephalitis at the time of primary viral infection. Meanwhile, this virus can reactivate in transplant recipients and cause post-trasplant limbic encephalitis. It has been demonstrated that neuroimaging analysis particularly MRI image is useful for diagnosis of post-transplant HHV-6B encephalitis. As high copies of viral DNA are detected in patient's CSF, direct invasion of HHV-6B might play important role in causing the disease. Ganciclovir or foscarnet could be effective against HHV-6B based on in vitro analysis.