Refractory Absence Epilepsy and Glut1 Deficiency Syndrome: A New Case Report and Literature Review

We report a 12-year-old female patient with a mild phenotype of glucose transporter type 1 deficiency syndrome (Glut1D). The clinical picture was characterized by refractory absence epilepsy, migraine, and learning disabilities. Absence seizures appeared at the age of 4 years, and electroencephalogram (EEG) showed irregular discharges of diffuse epileptic abnormalities. During the follow-up, seizures became drug resistant, cognitive evaluation revealed learning difficulties, and the patient complained migraine episodes. The evidence of seizure worsening before meals and the drug resistance suggested a Glut1D. Molecular analysis of SLC2A1 gene showed the presence of a pathogenic de novo mutation of the gene in heterozygosity (p.Ala275Thr, c.823G > A). Our case and the review of literature data on patients with Glut1D and absences provide a combination of clinical and EEG keys that should prompt the genetic analysis. The Glut1D should be suspected when absence seizures are associated with at least one among: irregular ictal EEG discharges, mild mental retardation, migraine, microcephaly, drug resistance, and worsening during fasting. An early diagnosis allows to establish one of the available ketogenic regimens which could modify the natural history of this treatable condition.