title: Glucose transporter-1 (GLUT1) deficiency syndrome: diagnosis and treatment in late childhood.
abstract: BACKGROUND
  Typical cases of glucose transporter-1 deficiency syndrome (GLUT1-DS) present with early-onset epilepsy. We report symptoms, diagnostic results, and effects of therapy in two patients diagnosed with GLUT1-DS at the age of 10 and 15 years, respectively.
  
  
  METHODS
  Patient 1: After four cerebral seizures in the first 2 years of life the patient was seizure-free but showed a complex movement disorder, expressive speech disorder, and mental retardation. Ratio of cerebrospinal fluid (CSF) to blood glucose was 0.41 (reference range 0.65 ± 0.1), molecular genetic testing confirmed GLUT1 deficiency with the novel pathogenic mutation c.1377dupC (p.Phe460LeufsX3) in the SLC2A1 gene. Following 9 months of ketogenic diet started at the age of 10 years, there was distinct improvement of speech and movement disorder. Patient 2 showed pharmacorefractive epilepsy, mental retardation, and a mild movement disorder. At the age of 15 years, extensive intake of food with high fat content was observed. Ratio of CSF to blood glucose was 0.41 (reference range 0.65 ± 0.1). The pathogenic mutation c.634C>T (p.Arg212Cys) was found in the SLC2A1 gene.
  
  
  CONCLUSIONS
  Self-induced high-fat diet can be a hint toward GLUT1-DS. Ketogenic diet can be beneficial even when started in late childhood, although it may take several months to achieve a positive effect.
authors.affiliation: Division of Metabolic Disorders, Department of General Paediatrics, Centre for Paediatric and Adolescent Medicine, Heidelberg, Germany. gwendolyn.gramer@med.uni-heidelberg.de
authors.forename: Gwendolyn
authors.initials: G
authors.lastname: Gramer
authors.forename: Nicole I
authors.initials: NI
authors.lastname: Wolf
authors.forename: Daniel
authors.initials: D
authors.lastname: Vater
authors.forename: Thomas
authors.initials: T
authors.lastname: Bast
authors.forename: René
authors.initials: R
authors.lastname: Santer
authors.forename: Erik-Jan
authors.initials: EJ
authors.lastname: Kamsteeg
authors.forename: Ron A
authors.initials: RA
authors.lastname: Wevers
authors.forename: Friedrich
authors.initials: F
authors.lastname: Ebinger
mesh_terms: D000293:Adolescent; D002648:Child; D004827:Epilepsy / Q000235:genetics*; D005260:Female; D051272:Glucose Transporter Type 1 / Q000172:deficiency* / Q000235:genetics; D006801:Humans; D008297:Male; D013577:Syndrome
chemical_list: D051272:Glucose Transporter Type 1