Clinical analysis of pyridoxine-dependent epilepsy in a child and ALDH7A1 mutation

Abstract

Objective To analyze clinical diagnosis and treatment, aldehyde dehydrogenase 7 family member A1(ALDH7A1) gene mutations in 1 Chinese child with pyridoxine dependent epilepsy(PDE). Methods The clinical manifestations and course of treatment were observed in a PDE patient with early epilepsy onset.Video-electroencephalogram(VEEG) and magnetic resonance imaging(MRI) were performed.The mutations of ALDH7A1 gene were exa-mined. Results At the age of 2 months, recurrent epileptic seizures occurred and the child was resistant to antiepileptic drugs.Patient hospitalized several times due to frequent seizures and pyridoxine was used intravenously for several days.For each hospital stay, the frequent seizures were controlled completely under the treatment of pyridoxine and antiepileptic drugs.Seizures recurred at intervals of 13, 14 and 38 days due to the treatment with antiepileptic drugs only without pyridoxine.Continuing oral pyridoxine without anticonvulsants led to seizure free for 5 months.No epileptiform discharges were found during several interictal VEEG monitoring and MRI showed normal.ALDH7A1 gene mutation analysis revealed two heterozygote mutations: c.410G>A(p.G137E) in exon 5 that was transmitted from the father, and IVS11+ 1G>A in intron 11 transmitted from the mother. Conclusions Early onset seizures have better response to pyridoxine and recurred after pyridoxine withdrawal in the patient, which suggested that he is a PDE patient.The interictal normal EEG could not rule out the possibility of PDE.This is the first report on ALDH7A1 mutations in PDE patient in China.Both the c. 410G>A(p.G137E) and IVS11+ 1G>A mutations have not been reported previously. Key words: Pyridoxine dependent epilepsy; Pyridoxine; Aldehyde dehydrogenase 7 family member A1 gene