[P2-67] The Ratio of Cerebrospinal Fluid Glucose / Blood Glucose is Correlated with the Severity of Glucose Transporter 1 Deficiency Syndrome
[Introduction] The disease course and severity in glucose transporter 1 deficiency syndrome (Glut-1DS) showed continuum. [Objective] We retrospectively examined the medical records of Glut-1DS patients in our hospital. This study was approved by ethical committee in the hospital. [Results] 31 patients (F19, M12) were included (The age of onset: 1mo-27yo (median 5m) and age at the diagnosis: 3mo-48yo (median 6y3m)). CSF glucose / blood sugar ratio (CGBSR) showed continuous distribution from 0.26 to 0.58. The mutation of SLC2A1 gene was identified in 27 patients. Ketogenic diet or modified Atkins diet was introduced (KD) in 26 patients. Patients were classified into two groups: severer group whose CGBSR < 0.40 (N=17) and milder CGBSR ≥ 0.40 (N=14). The number of patients who showed developmental delay as walk alone after 18 month, and using words after 18 month were 15 and 11 in severer patients and 4 and 5 in milder ones. In severer group, all patients suffered from daily to monthly epileptic seizures, and only two patients experienced complete relief of seizures by KD. The severest patients, whose CGBSR < 0.35, suffered from monthly seizure even they kept strict KD. In the milder group, patients seldom experienced monthly seizure. One patient did not have epilepsy and two only absence seizures. In both groups, VPA was effective to eliminate the refractory seizures under strict KD. [Conclusion] CGBSR was correlated with development and epilepsy severity, and it delineates natural history of Glut-1DS of diverse severity.