title: Primary human herpesvirus-6 infection in the central nervous system can cause severe disease.
abstract: Human herpesvirus-6 (HHV-6) infection is common in infancy, and symptoms are usually mild. However, encephalitis and other neurologic complications have been reported. Primary HHV-6 infection has been rarely confirmed in the central nervous system. We studied 21 children with suspected HHV-6 infection, drawn from a prospective, large-scale study of neurologic infections in Finland. Human herpesvirus-6 polymerase chain reaction was performed on cerebrospinal fluid samples, and antibody tests were performed on serum and cerebrospinal fluid. We identified nine children, aged 3 to 24 months, who had HHV-6-specific nucleic acid in cerebrospinal fluid. Primary infection was confirmed by seroconversion of specific antibodies in six, whereas one had a fourfold increase, and one had a fourfold decrease, in the antibody titer supporting recent infection. Generalized and prolonged seizures appeared in six children, four had a rash, four had ataxia, and four had gastroenteritis. All but two had a high fever. At follow-up, four children had evident neurologic sequelae, ataxia, and developmental disability, and needed special education. Primary HHV-6 infection may invade the central nervous system, and can cause neurologic symptoms and potentially permanent disability in children aged <or=2 years. The possibility of HHV-6 infection must be considered when treating acutely ill children, and especially those with convulsions.
authors.affiliation: Haartman Institute, Department of Virology, University of Helsinki, Helsinki, Finland. laura.mannonen@helsinki.fi
authors.forename: Laura
authors.initials: L
authors.lastname: Mannonen
authors.forename: Eila
authors.initials: E
authors.lastname: Herrgård
authors.forename: Pekka
authors.initials: P
authors.lastname: Valmari
authors.forename: Paula
authors.initials: P
authors.lastname: Rautiainen
authors.forename: Kari
authors.initials: K
authors.lastname: Uotila
authors.forename: Marjo-Riitta
authors.initials: MR
authors.lastname: Aine
authors.forename: Pirkko
authors.initials: P
authors.lastname: Karttunen-Lewandowski
authors.forename: Juhani
authors.initials: J
authors.lastname: Sankala
authors.forename: Tiina
authors.initials: T
authors.lastname: Wallden
authors.forename: Marjaleena
authors.initials: M
authors.lastname: Koskiniemi
mesh_terms: D001259:Ataxia / Q000821:virology; D020805:Central Nervous System Viral Diseases / Q000150:complications* / Q000175:diagnosis; D015331:Cohort Studies; D004279:DNA, Viral / Q000134:cerebrospinal fluid; D002658:Developmental Disabilities / Q000821:virology; D005260:Female; D005387:Finland; D015654:Herpesvirus 6, Human / Q000302:isolation & purification*; D006801:Humans; D007223:Infant; D008297:Male; D016133:Polymerase Chain Reaction; D019349:Roseolovirus Infections / Q000150:complications* / Q000175:diagnosis; D012640:Seizures / Q000821:virology*; D012698:Serologic Tests
chemical_list: D004279:DNA, Viral