Focal non-motor seizures and subsequent focal motor seizures as the main clinical expression of GLUT-1 deficiency

Abstract

The seizure type most frequently described in GLUT1 deficiency is generalized (mainly absence). We report the case of a young boy who, as the main clinical manifestation presented with focal non-motor, and then focal motor seizures.At the age of 3 months episodes of face pallor/cyanosis and hypotonus lasting about 1 min, occurred. They were initially misdiagnosed as gastroesophageal reflux. These episodes disappeared spontaneously at 6 months of age. At 12 months, episodes similar to the previous ones reappeared. A few months later, a cluster of several episodes manifest as impaired responsiveness and vomiting occurred. The patient initially performed long-term video-EEG monitoring (LTVEM) however, no seizures were captured. During a second hospitalization for LTVEM, a focal to bilateral clonic seizure was recorded. Brain MRI was normal. Next Generation Sequencing (NGS) panel for genes associated with epilepsy showed a de novo mutation of SCL2A1 gene. The CSF showed glucose of 41 mg/dL, and the CSF/serum glucose ratio was equal to 0.46. The ketogenic diet was started with optimal efficacy in seizure control.Meal-sensitivity in childhood onset focal seizures may be associated with GLUT-1 deficiency syndrome that can be confirmed by biochemical analysis on blood and CSF following diagnostic genetic study.

Keywords

• Glut1 deficiency
• SCL2A1
• Childhood epilepsy
• Brain energy failure syndrome
• Treatable epilepsy