Tomoyuki Noguchi, Presenter: Nothing to Disclose

Futoshi Mihara MD, PhD, Abstract Co-Author: Nothing to Disclose

Takashi Yoshiura MD,PhD, Abstract Co-Author: Nothing to Disclose

Osamu Togao MD, Abstract Co-Author: Nothing to Disclose

Kazushige Atsumi, Abstract Co-Author: Nothing to Disclose

Takashi Matsuura MD, PhD, Abstract Co-Author: Nothing to Disclose

Toshiro Kuroiwa, Abstract Co-Author: Nothing to Disclose

Hiroshi Honda MD, Abstract Co-Author: Nothing to Disclose

et al, Abstract Co-Author: Nothing to Disclose

Human herpesvirus-6 (HHV-6) associated encepalopathy in adults is one of causes of central nervous system problems in immunocompromised patients. Only a few reports have described the imaging characteristics of this disease. We retrospectively reviewed clinical and imaging findings of six adult cases of HHV-6 associated encephalopathy.

From 2003 to 2005, we encountered six cases of HHV-6 associated encephalopathy (4 men and 2 woman, age range: 36-55 years old, median age: 49 years old) in three hospitals. The diagnosis was established by detection of HHV-6 DNA in the cerebrospinal fluid or the peripheral blood by polymerase chain reaction.

Primary disorders included acute leukemia in three patients and non-Hodgkin lymphoma in the other three. Cord blood stem cell transplant was performed in one, peripheral blood stem cell transplant in one, and bone marrow transplant in four. The neurological symptoms were amnesia (67%), disorientation (67%), hypopnea (50%), coma (50%) and seizure (33%). In three patients, head CT was obtained within one days from onset, which resulted in no remarkable abnormal findings. On initial or follow-up MR obtained on the day to 71st days, all six patients showed abnormal findings at unilateral or bilateral mesial temporal lobe (hippocampus and surrounding structures): hyperintensity on FLAIR in five of six patients (83%); hyperintensity on diffusion-weighted images (DWI) in three of five patients (60%); focal atrophic change at the affected lobe in later phase in five of six patients (83%).

In our series, HHV-6 associated encephalopathy in adults tended to affect the mesial temporal lobe. MR is sensitive tool for HHV-6 associated encephalopathy in immunocompromised patients. Especially, FLAIR and DWI may be useful for detection and follow-up of this disease.

Noguchi, T, Mihara, F, Yoshiura, T, Togao, O, Atsumi, K, Matsuura, T, Kuroiwa, T, Honda, H, et al, , Human Herpes Virus 6 (HHV-6) Associated Encephalopathy in Adults.  Radiological Society of North America 2005 Scientific Assembly and Annual Meeting, November 27 - December 2, 2005 ,Chicago IL. http://archive.rsna.org/2005/4415881.html