title: Detection and typing of human herpesvirus 6 by molecular methods in specimens from patients diagnosed with encephalitis or meningitis.
abstract: Human herpesvirus 6 (HHV-6) was detected in specimens from patients hospitalized with symptoms of encephalitis or meningitis. A real-time PCR assay was developed which has a linear dynamic range of 5 to 5 x 10(6) copies of HHV-6 and a sensitivity of five gene copies per reaction. While the assay detects both subtypes, HHV-6A and HHV-6B, it is specific and does not cross-react with a selected specificity panel. A total of 1,482 patient specimens, which were collected between 2003 and 2007, were tested; 26 specimens from 24 patients were found to be positive for HHV-6 by real-time PCR. The HHV-6 detection rate in this population was therefore 1.75%. The majority of the specimens tested (>95%) were cerebrospinal fluid (CSF) specimens. We were able to type 20 of the 26 positive specimens by conventional PCR and sequence analysis; all were HHV-6B. Forty-two percent of the patients were 3 years of age or younger, which may indicate a primary infection in these patients. Given the ages of the remaining patients (from 4 to 81 years), their infections were most probably due to virus reactivations. Where information was available, symptoms of patients included fever (71%), altered mental status (67%), and abnormal CSF profile (75%). Fifty percent of patients of 3 years of age or younger suffered from seizures. The detection of HHV-6 in specimens from patients diagnosed with encephalitis or meningitis, in the absence of a positive PCR result for other agents, strongly suggests a role for HHV-6 in the pathogenesis of these central nervous system diseases.
authors.affiliation: Wadsworth Center, New York State Department of Health, Albany, NY, USA. norma.tavakoli@wadsworth.org
authors.forename: Norma P
authors.initials: NP
authors.lastname: Tavakoli
authors.forename: Seela
authors.initials: S
authors.lastname: Nattanmai
authors.forename: Rene
authors.initials: R
authors.lastname: Hull
authors.forename: Heather
authors.initials: H
authors.lastname: Fusco
authors.forename: Lela
authors.initials: L
authors.lastname: Dzigua
authors.forename: Heng
authors.initials: H
authors.lastname: Wang
authors.forename: Michelle
authors.initials: M
authors.lastname: Dupuis
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D002555:Cerebrospinal Fluid / Q000821:virology; D002648:Child; D002675:Child, Preschool; D004279:DNA, Viral / Q000235:genetics; D018792:Encephalitis, Viral / Q000453:epidemiology / Q000503:physiopathology / Q000821:virology*; D005260:Female; D015654:Herpesvirus 6, Human / Q000145:classification / Q000302:isolation & purification*; D006801:Humans; D007223:Infant; D008297:Male; D008587:Meningitis, Viral / Q000453:epidemiology / Q000503:physiopathology / Q000821:virology*; D008875:Middle Aged; D016133:Polymerase Chain Reaction / Q000379:methods*; D019349:Roseolovirus Infections / Q000150:complications* / Q000453:epidemiology / Q000503:physiopathology / Q000821:virology*; D012680:Sensitivity and Specificity
chemical_list: D004279:DNA, Viral