title: Antiviral therapy of two patients with chromosomally-integrated human herpesvirus-6A presenting with cognitive dysfunction.
abstract: BACKGROUND
  Human herpesvirus 6 (HHV-6) is a neurotropic virus implicated in central nervous system (CNS) dysfunction, multiple sclerosis, seizures and encephalitis. Inherited or "chromosomally integrated" HHV-6 (CIHHV-6) is a condition characterized by high DNA loads and germ line transmission of HHV-6 genomes, which are integrated into the telomere.
  
  
  OBJECTIVE
  We previously reported that integrated HHV-6 can be reactivated by trichostatin A in vitro. Therefore, we hypothesized that a broad array of neurological symptoms of CIHHV-6 patients may respond to antiviral drug treatment.
  
  
  METHODS
  The patients have been treated with antiviral drugs and monitored for viral load, late mRNA, and clinical improvement.
  
  
  RESULTS
  Antiviral therapy of two CIHHV patients resulted in successful clinical resolution. However, both patients relapsed on multiple occasions within 4-6 months of cessation of antiviral therapy.
  
  
  CONCLUSIONS
  Successful antiviral drug treatment suggests that clinical symptoms of these patients were due to symptomatic reactivation of CIHHV-6. Alternatively, some CIHHV-6 patients may have a reduced resistance to community-acquired HHV-6 strains due to tolerance leading to persistent infections.
authors: Division of Infectious Diseases and Geographic Medicine, Department of Medicine, Stanford University Medical Center, Stanford, CA 94305, USA.
authors: José G
authors: JG
authors: Montoya
authors: Michael N
authors: MN
authors: Neely
authors: Sudhir
authors: S
authors: Gupta
authors: Mitchell R
authors: MR
authors: Lunn
authors: Kristin S
authors: KS
authors: Loomis
authors: Joshua C
authors: JC
authors: Pritchett
authors: Bruce
authors: B
authors: Polsky
authors: Peter G
authors: PG
authors: Medveczky
mesh_terms: D000998:Antiviral Agents / Q000627:therapeutic use*; D002648:Child; D003072:Cognition Disorders / Q000821:virology*; D004279:DNA, Viral / Q000097:blood; D004569:Electroencephalography; D005260:Female; D015654:Herpesvirus 6, Human / Q000235:genetics*; D006801:Humans; D007958:Leukocyte Count; D008297:Male; D012333:RNA, Messenger / Q000097:blood; D019349:Roseolovirus Infections / Q000188:drug therapy* / Q000235:genetics / Q000523:psychology / Q000821:virology; D035781:Siblings; D019562:Viral Load; D016662:Virus Integration; D055815:Young Adult
chemical_list: D000998:Antiviral Agents; D004279:DNA, Viral; D012333:RNA, Messenger