title: Epileptic phenotype of FGFR3-related bilateral medial temporal lobe dysgenesis.
abstract: Hypochondroplasia (HCH) is a skeletal dysplasia, characterized by short stature and macrocephaly. Clinical symptoms and radiological and histopathological features of HCH are similar, but milder than those seen in achondroplasia. Particularly, HCH patients with Asn540Lys mutation in the FGFR3 gene are reported to have medial temporal lobe dysgenesis and epilepsy. We report a 3-year-old girl who developed recurrent epileptic apnea, which started immediately after birth. The apneic seizures were refractory to antiepileptic medications; ictal electroencephalography showed rhythmic activity originating from the left or right temporal areas and rarely from the right frontal area. Macrocephaly was noted since birth. Neuroimaging revealed bilateral dysgenesis and hypometabolism of the medial temporal structures as well as perfusion changes in the left lateral temporofrontal areas during the ictal period. Clonazepam was initiated and acetazolamide dosage was increased at 6months, resulting in complete seizure control after 8months of age. Genetic analysis identified an Asn540Lys (c.1620 C>A) mutation in the FGFR3 gene. Characteristic bone findings on the lumbar spine, iliac bone, and femur were retrospectively confirmed on X-rays during infancy. This was the first report that delineated the epilepsy phenotype in FGFR3-related bilateral medial temporal lobe dysgenesis; such findings would lead to an early diagnosis and better epilepsy management.
authors.affiliation: Division of Child Neurology, Department of Brain and Neurosciences, Faculty of Medicine, Tottori University, Yonago, Japan. Electronic address: t-okazaki@med.tottori-u.ac.jp.
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Okazaki
authors.affiliation: Division of Child Neurology, Department of Brain and Neurosciences, Faculty of Medicine, Tottori University, Yonago, Japan; Department of Child Neurology, National Center of Neurology and Psychiatry, Tokyo, Japan.
authors.forename: Yoshiaki
authors.initials: Y
authors.lastname: Saito
authors.affiliation: Division of Child Neurology, Department of Brain and Neurosciences, Faculty of Medicine, Tottori University, Yonago, Japan; Department of Child Neurology, National Center of Neurology and Psychiatry, Tokyo, Japan.
authors.forename: Riyo
authors.initials: R
authors.lastname: Ueda
authors.affiliation: Department of Child Neurology, National Center of Neurology and Psychiatry, Tokyo, Japan.
authors.forename: Takeya
authors.initials: T
authors.lastname: Awashima
authors.affiliation: Division of Child Neurology, Department of Brain and Neurosciences, Faculty of Medicine, Tottori University, Yonago, Japan.
authors.forename: Yoko
authors.initials: Y
authors.lastname: Nishimura
authors.affiliation: Division of Legal Medicine, Faculty of Medicine, Tottori University, Yonago, Japan.
authors.forename: Isao
authors.initials: I
authors.lastname: Yuasa
authors.affiliation: Division of Radiology, Department of Pathophysiological Therapeutic Science, Faculty of Medicine, Tottori University, Yonago, Japan.
authors.forename: Yuki
authors.initials: Y
authors.lastname: Shinohara
authors.affiliation: Division of Functional Genomics, Research Center for Bioscience and Technology, Tottori University, Yonago, Japan.
authors.forename: Kaori
authors.initials: K
authors.lastname: Adachi
authors.affiliation: Department of Child Neurology, National Center of Neurology and Psychiatry, Tokyo, Japan.
authors.forename: Masayuki
authors.initials: M
authors.lastname: Sasaki
authors.affiliation: Division of Functional Genomics, Research Center for Bioscience and Technology, Tottori University, Yonago, Japan.
authors.forename: Eiji
authors.initials: E
authors.lastname: Nanba
authors.affiliation: Division of Child Neurology, Department of Brain and Neurosciences, Faculty of Medicine, Tottori University, Yonago, Japan.
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Maegaki
mesh_terms: D000015:Abnormalities, Multiple / Q000000981:diagnostic imaging / Q000235:genetics* / Q000503:physiopathology; D001842:Bone and Bones / Q000002:abnormalities* / Q000000981:diagnostic imaging / Q000503:physiopathology; D002675:Child, Preschool; D002658:Developmental Disabilities / Q000000981:diagnostic imaging / Q000235:genetics / Q000503:physiopathology; D003937:Diagnosis, Differential; D004392:Dwarfism / Q000000981:diagnostic imaging / Q000235:genetics* / Q000503:physiopathology; D004833:Epilepsy, Temporal Lobe / Q000000981:diagnostic imaging / Q000188:drug therapy / Q000235:genetics* / Q000503:physiopathology; D005260:Female; D006801:Humans; D017880:Limb Deformities, Congenital / Q000000981:diagnostic imaging / Q000235:genetics* / Q000503:physiopathology; D008141:Lordosis / Q000000981:diagnostic imaging / Q000235:genetics* / Q000503:physiopathology; D010641:Phenotype; D051498:Receptor, Fibroblast Growth Factor, Type 3 / Q000235:genetics*; D012868:Skin Abnormalities / Q000000981:diagnostic imaging / Q000235:genetics* / Q000503:physiopathology; D013702:Temporal Lobe / Q000002:abnormalities* / Q000000981:diagnostic imaging / Q000187:drug effects / Q000503:physiopathology
chemical_list: C496365:FGFR3 protein, human; D051498:Receptor, Fibroblast Growth Factor, Type 3
keywords: Epileptic apnea; FGFR3; Hypochondroplasia; Temporal lobe dysgenesis; Temporal lobe epilepsy