The Clinical Features And Gene Mutations Analysis Of 25 Children With Epileptic Encephalopathy

ObjectiveWe summarized the clinical features and invesdigate gene mutations in 25 children with Epileptic encephalopathy.MethodsWe used targeted next-generation sequencing to detect gene mutations in 25 Chinese children were diagnosed with Epileptic encephalopathy in children’s Hospital of Chongqing Medical University from October 2014 to November 2015. A series of filtering criteria was used to find the possible pathogenic variations. Validation and parental origin analyses were performed by Sanger sequencing. We reviewed the phenotypes of patients with each mutated gene.Results1.The peak onset age of Infantile epileptic encephalopathy was under 1 year of age(76%), West syndrome and Dravet syndrome were the main type(19 / 25, 76%),with various forms of seizure, the effect is not unsatisfied, need drug combination therapy(17/22, 77.3%), most of them(12/22, 81.8%) were with mental retardation or regression.2.Genotype and phenotype analysis:(1)12 cases of West syndrome: 7 cases had clear pathogenic gene mutation(TSC2 gene in 4 cases, STXBP1 gene in 1, KCNQ2 gene in 2). The other 5 cases are not clear, in which 3 cases of RYR3 gene mutation, may be the new discovery of the West syndrome gene.1 cases of ohtahara syndrome has a clear pathogenic gene(STXBP1 gene), has been clinically turned into infantile spasm.(2)7 cases of Dravet syndrome: 6 cases with SCN1 A gene mutation.(3)In 5 patients diagnosed with unknown type of EE, 1 detected with CTNNA3 gene mutation,4 cases were not clear or not detected.Conclusion1.The same gene mutation in different epilepsy syndrome in children may has similar or overlapping phenotypes. Some gene mutations with genetic heterogeneity.2.Interpretation of the gene report need be carefully, when pathogenicity is not clear or pathogenic genes were not detected, need to combine with family analysis, phenotype, and gene type of co segregation analysis.