Early-onset absence epilepsy associated with GLUT 1 deficiency

Abstract

We describe a 4.5-year-old girl with an unremarkable personal and family history. At 16 mo of age, she had a single generalized tonic-clonic seizure while awake. At 3 yr of age, she started with daily absence seizures while awake and hyperki- netic and aggressive behavior. The interictal electroencephalography showed bilateral temporo-occipital spike and wave com- plexes. The ictal video-electroencephalography recordings showed symmetric or asymmetric and synchronized spike and wave paroxysms associated with absences. Neurological examination revealed motor clumsiness, ataxia, and receptive and expressive language deficits. Routine laboratory and imaging studies as well as blood and urine neuro-metabolic investigations were normal. The absences were refractory to antiepileptic drugs. Cerebrospinal fluid glucose concentration was 36 mg/dL, lac- tate concentration was 1 mmol/L, and cerebrospinal fluid/plasma glucose ratio was 0.49. Based on the electro-clinical manifes- tations, neurological examination, and the metabolic study results, glucose transporter-1 deficiency was diagnosed and the girl was started on the ketogenic diet with good response.