title: A case of Høyeraal-Hreidarsson syndrome: delayed myelination and hypoplasia of corpus callosum are other important signs.
abstract: We report the case of a 7-year old girl with Høyeraal-Hreidarsson syndrome (HHS) and review other cases of HHS. In addition to the previously described important signs of HHS, i.e., prenatal growth retardation, microcephaly, psychomotor retardation, progressive pancytopenia, immunological abnormalities, and cerebellar hypoplasia and ataxia, we consider that delayed myelination of cerebral white matter and hypoplastic corpus callosum should be added to the list of important signs. However, it is not clear whether delayed myelination of white matter in HHS indicates dysmyelination or demyelination. Furthermore, we suggest that immunological abnormalities of both T and B cells are one of the important signs of HHS. We consider these new important signs to be valuable for the diagnosis of HHS.
authors.affiliation: Division of Child Neurology, Institute of Neurological Sciences, Faculty of Medicine, Tottori University, Yonago, Japan.
authors.forename: S
authors.initials: S
authors.lastname: Akaboshi
authors.forename: M
authors.initials: M
authors.lastname: Yoshimura
authors.forename: T
authors.initials: T
authors.lastname: Hara
authors.forename: H
authors.initials: H
authors.lastname: Kageyama
authors.forename: K
authors.initials: K
authors.lastname: Nishikwa
authors.forename: T
authors.initials: T
authors.lastname: Kawakami
authors.forename: A
authors.initials: A
authors.lastname: Ieshima
authors.forename: K
authors.initials: K
authors.lastname: Takeshita
mesh_terms: D061085:Agenesis of Corpus Callosum; D002524:Cerebellar Ataxia / Q000150:complications* / Q000175:diagnosis / Q000235:genetics; D002648:Child; D005260:Female; D006801:Humans; D007111:Immunity, Cellular; D008279:Magnetic Resonance Imaging; D008831:Microcephaly / Q000150:complications*; D009413:Nerve Fibers, Myelinated / Q000473:pathology*; D010198:Pancytopenia / Q000150:complications* / Q000235:genetics / Q000276:immunology; D013577:Syndrome; D013921:Thrombocytopenia / Q000150:complications* / Q000235:genetics / Q000276:immunology