title: Human herpesvirus-6B active infection associated with relapsing bilateral anterior optic neuritis.
abstract: OBJECTIVE
  Human herpesvirus-6 (HHV-6) is the causative agent of exanthem subitum. Both HHV-6 variants, A and B, have been associated with central nervous system (CNS) diseases, suggesting a wide neuropathogenic potential. We describe a case of recurrent bilateral anterior optic neuritis with HHV-6 active infection associated with clinical relapses.
  
  
  METHODS
  A 23-year old woman presented with progressive visual impairment, bilateral papillitis and painful ocular movements. Nested polymerase chain reaction (PCR) for DNA viruses, HHV-6 variant specific real time quantitative PCR, serological analysis and retrotranscription PCR (RT-PCR) for HHV-6 mRNA transcripts were performed. Nested PCR in PBMC and CSF samples was negative for all viruses but positive for HHV-6 DNA, subtyped as HHV-6B. The disease had a relapsing/remitting course. During relapses PBMC samples remained positive for HHV-6 DNA, and HHV-6 active infection was confirmed by the presence of anti-HHV-6 IgM and of HHV-6 U27 mRNA transcript. High viremia levels and relapses were overlapping. After the last relapse, the patient was successfully treated with gancyclovir.
  
  
  CONCLUSIONS
  The case reported here suggests a possible association of HHV-6 in bilateral optic neuritis. HHV-6 could be monitored when bilateral optic neuritis is identified, in order to establish an appropriate antiviral therapy.
authors.affiliation: Department of Molecular Biology, Microbiology and Virology Section, University of Siena, Policlinico Le Scotte, Tower 5, Level 2, Viale Bracci 1, 53100 Siena, Italy.
authors.forename: D
authors.initials: D
authors.lastname: Moschettini
authors.forename: R
authors.initials: R
authors.lastname: Franceschini
authors.forename: N M
authors.initials: NM
authors.lastname: Vaccaro
authors.forename: C
authors.initials: C
authors.lastname: Cermelli
authors.forename: F
authors.initials: F
authors.lastname: Pezzini
authors.forename: M
authors.initials: M
authors.lastname: Balestrieri
authors.forename: A
authors.initials: A
authors.lastname: Cerase
authors.forename: S
authors.initials: S
authors.lastname: Bartalini
authors.forename: M
authors.initials: M
authors.lastname: Ulivelli
authors.forename: G M
authors.initials: GM
authors.lastname: Tosi
authors.forename: D
authors.initials: D
authors.lastname: Donati
mesh_terms: D000328:Adult; D004279:DNA, Viral / Q000032:analysis / Q000235:genetics; D005260:Female; D006566:Herpesviridae Infections / Q000175:diagnosis / Q000453:epidemiology / Q000821:virology*; D015654:Herpesvirus 6, Human / Q000302:isolation & purification*; D006801:Humans; D009902:Optic Neuritis / Q000175:diagnosis / Q000821:virology*; D020133:Reverse Transcriptase Polymerase Chain Reaction
chemical_list: D004279:DNA, Viral