title: Exanthem subitum-associated encephalitis: nationwide survey in Japan.
abstract: We sought to clarify clinical features of exanthem subitum associated-encephalitis/encephalopathy, generally caused by primary human herpesvirus-6 infection in Japan. A two-part questionnaire was sent to hospitals between January 2003-December 2004. Of 3357 questionnaires, 2357 (70.2%) were returned, and 2293 (68.3%) were eligible for analysis. Eighty-six cases of exanthem subitum-associated encephalitis/encephalopathy were reported. Seventy-seven (89.5%) of 86 patients were diagnosed with human herpesvirus-6 infection by virologic examination. Although 41 (50.6%) of 81 patients had no sequelae, 38 (46.9%) had neurologic sequelae. Moreover, two fatal cases (2.5%) were reported. Pleocytosis was evident in only 4 (7.5%) of 53 patients, and cerebrospinal fluid protein levels were within normal range (23.4 +/- 14.6 mg/dL S.D.) in all patients. Human herpesvirus-6 DNA was detected in 21 (53.8%) of 39 patients. Abnormal computed tomography findings were a predictor of neurologic sequelae (P = 0.0097). As a consequence of this survey, we estimate that 61.9 cases of exanthem subitum-associated encephalitis occur every year. The disease prognosis was unexpectedly poor.
authors.affiliation: Department of Pediatrics, Fujita Health University School of Medicine, Toyoake, Aichi, Japan. tetsushi@fujita-hu.ac.jp
authors.forename: Tetsushi
authors.initials: T
authors.lastname: Yoshikawa
authors.forename: Masahiro
authors.initials: M
authors.lastname: Ohashi
authors.forename: Fumi
authors.initials: F
authors.lastname: Miyake
authors.forename: Ayano
authors.initials: A
authors.lastname: Fujita
authors.forename: Chie
authors.initials: C
authors.lastname: Usui
authors.forename: Ken
authors.initials: K
authors.lastname: Sugata
authors.forename: Sadao
authors.initials: S
authors.lastname: Suga
authors.forename: Shuji
authors.initials: S
authors.lastname: Hashimoto
authors.forename: Yoshizo
authors.initials: Y
authors.lastname: Asano
mesh_terms: D002675:Child, Preschool; D004279:DNA, Viral; D018792:Encephalitis, Viral / Q000134:cerebrospinal fluid / Q000150:complications / Q000453:epidemiology* / Q000473:pathology; D005077:Exanthema Subitum / Q000134:cerebrospinal fluid / Q000150:complications / Q000453:epidemiology* / Q000473:pathology; D005260:Female; D015654:Herpesvirus 6, Human / Q000235:genetics / Q000302:isolation & purification; D006801:Humans; D007223:Infant; D007564:Japan / Q000453:epidemiology; D007964:Leukocytosis / Q000134:cerebrospinal fluid / Q000453:epidemiology / Q000473:pathology; D008279:Magnetic Resonance Imaging; D008297:Male; D011379:Prognosis; D011795:Surveys and Questionnaires; D014057:Tomography, X-Ray Computed
chemical_list: D004279:DNA, Viral