Antonino Romeo1, Monica Lodi2, Maurizio Viri2, Eliana Parente2, Maurizia Baldi3, Andrea Righini4, Donatella Milani5. 1. Pediatric Neurology Unit and Epilepsy Center, Department of Neuroscience, "Fatebenefratelli e Oftalmico" Hospital, Milano, Italy. Electronic address: antonino.romeo@fbf.milano.it. 2. Pediatric Neurology Unit and Epilepsy Center, Department of Neuroscience, "Fatebenefratelli e Oftalmico" Hospital, Milano, Italy. 3. Laboratory of Human Genetic, Italy, Molecular Biology, "Galliera" Hospital, Genova, Italy. 4. Radiology and Neuroradiology Department, Children's Hospital "V. Buzzi", Milano, Italy. 5. Pediatric Clinic I, Department of Pathophysiology and Transplantation, University of Milan Fondazione IRCCS Ca' Granda, Ospedale Maggiore Policlinico, Milano, Italy.
Abstract
BACKGROUND: Hypochondroplasia is a rare skeletal dysplasia characterized by disproportionately short stature, lumbar lordosis, and limited extension of the elbow caused by mutations in the fibroblast growth factor receptor 3 (FGFR3) gene that plays a role in controlling nervous system development. Hypochondroplasia with FGFR3 mutation associated with bilateral medial temporal lobe anomalies and focal epilepsy was previously reported in several patients. PATIENT: We report clinical, electroclinical, and neuroradiological findings of one patient affected by hypochondroplasia. RESULTS: Clinical diagnosis was confirmed by molecular analysis of the FGFR3 gene, which showed a N540 K mutation. The patient had normal psychomotor development and showed early-onset focal seizures with left temporal localization on interictal and ictal electroencephalograph. The seizures were well controlled, and the patient has been seizure-free since infancy. Magnetic resonance imaging showed abnormal anteriorly posteriorly infolding in the hippocampus and abnormally oriented parahippocampus sulci, and additional cortical rim dysplasia with gray-white matter junction blurring in the hippocampus. CONCLUSIONS: The present case of hypochondroplasia and FGFR3 mutation in Asn540Lys associated with characteristic abnormalities involving bilaterally medial temporal lobe structures, probable hippocampal cortex focal dysplasia, and early onset of focal epilepsy underscores the possibility of a rare syndrome.
BACKGROUND:Hypochondroplasia is a rare skeletal dysplasia characterized by disproportionately short stature, lumbar lordosis, and limited extension of the elbow caused by mutations in the fibroblast growth factor receptor 3 (FGFR3) gene that plays a role in controlling nervous system development. Hypochondroplasia with FGFR3 mutation associated with bilateral medial temporal lobe anomalies and focal epilepsy was previously reported in several patients. PATIENT: We report clinical, electroclinical, and neuroradiological findings of one patient affected by hypochondroplasia. RESULTS: Clinical diagnosis was confirmed by molecular analysis of the FGFR3 gene, which showed a N540 K mutation. The patient had normal psychomotor development and showed early-onset focal seizures with left temporal localization on interictal and ictal electroencephalograph. The seizures were well controlled, and the patient has been seizure-free since infancy. Magnetic resonance imaging showed abnormal anteriorly posteriorly infolding in the hippocampus and abnormally oriented parahippocampus sulci, and additional cortical rim dysplasia with gray-white matter junction blurring in the hippocampus. CONCLUSIONS: The present case of hypochondroplasia and FGFR3 mutation in Asn540Lys associated with characteristic abnormalities involving bilaterally medial temporal lobe structures, probable hippocampal cortex focal dysplasia, and early onset of focal epilepsy underscores the possibility of a rare syndrome.
Authors: Irene J Chang; Angela Sun; Maryse L Bouchard; Shawn E Kamps; Susan Hale; Stephen Done; Michael J Goldberg; Ian A Glass Journal: Am J Med Genet A Date: 2018-07 Impact factor: 2.802