title: Sensory stimulus-sensitive drop attacks and basal ganglia calcification: new findings in a patient with FOLR1 deficiency.
abstract: Loss-of-function mutations in the FOLR1 gene (MIM *136430), encoding the folate receptor alpha, impair cerebral folate transport and lead to a progressive neurometabolic disorder. We report on a 5-year-old boy with progressive ataxia, from the age of 2 years and 6 months, with myoclonic jerks, regression, and impressive myoclonic tonic spasms with drop attacks, which were partially provoked by touching his face or washing his hands. Delayed myelination and cerebellar atrophy on cranial MRI were important clues to the diagnosis of cerebral folate transport deficiency, which was confirmed by homozygosity for the known nonsense mutation p.R204X in the FOLR1 gene. Computed tomography taken after head injury revealed bilateral calcifications in the basal ganglia as a novel finding in a patient with FOLR1 mutation.
authors.affiliation: Division of Neurology.
authors.forename: Sandra P
authors.initials: SP
authors.lastname: Toelle
authors.affiliation: Division of Neurology.
authors.forename: David
authors.initials: D
authors.lastname: Wille
authors.affiliation: Division of Neurology.
authors.forename: Bernhard
authors.initials: B
authors.lastname: Schmitt
authors.affiliation: Division of Diagnostic Imaging.
authors.forename: Ianina
authors.initials: I
authors.lastname: Scheer
authors.affiliation: Division of Metabolism, Chemistry and Biochemistry, University Children's Hospital Zurich, Switzerland.
authors.forename: Beat
authors.initials: B
authors.lastname: Thöny
authors.affiliation: Division of Neurology.
authors.forename: Barbara
authors.initials: B
authors.lastname: Plecko
mesh_terms: D001479:Basal Ganglia / Q000473:pathology* / Q000503:physiopathology; D002114:Calcinosis / Q000209:etiology*; D002675:Child, Preschool; D004569:Electroencephalography; D058975:Folate Receptor 1 / Q000172:deficiency*; D020022:Genetic Predisposition to Disease; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D009154:Mutation / Q000235:genetics; D013575:Syncope / Q000235:genetics* / Q000503:physiopathology; D014741:Video Recording / Q000379:methods
chemical_list: C548696:FOLR1 protein, human; D058975:Folate Receptor 1
keywords: FOLR1; MTHF; drop-attacks; hypomyelination; myoclonus