| Objective:SCN1A gene mutations are associated with epilepsy and neurodevelopmental disorders.This study aimed to explore the genotype and phenotype spectrum of SCNIA-gene related epilepsyMethods:Epileptic patients who were treated in the Children’s Hospital of Chongqing Medical University from January 2015 to July 2018 and identified as having SCN1A mutations by targeted next-generation sequencing were included.Clinical manifestations of all patients were analyzed retrospectivelyResults:A total of 24 patients with SCN1A mutations were identified The age of epilepsy onset ranged from 2 months to 2 years and 9 months(median age of 6 months).Multiple seizure types were observed.12 patients(50.0%)had three or more types of seizures,there was 4 patients who only had one type of seizures.16 patients(66.7%)had status epilepticus,11 patients(45.8%)had fever sensitivity,and 9 patients(37.5%)had seizures after vaccination.15 patients(62.5%)showed varying degrees of cognitive and motor development retardation.2 patients were diagnosed with Dravet syndrome and 5 patients were suspected of having Dravet syndrome.2 patients had mutations inherited from one of their parents and 22 patients(91.7%)had de novo mutations.The following SCN1A mutation types were identified:missense(16 patients,66.7%),nonsense(4 patients,16.7%),splice site(1 patient),frameshift(1 patient),and large deletions(2 patients).23 of the patients received antiepileptic therapy,of which 8 patients(33.3%)had no decrease in seizures and 11 patients(45.8%)had more than 50%decrease in seizure frequency.Three patients had poor response to AED therapy before attempting ketogenic diet,after which seizure frequency decreased by 50%.10 patients(41.7%)had used sodium channel blockers prior to accurate diagnosis,all of whom showed ineffective or even aggravated seizure response.Conclusions:SCN1A mutations are associated with a spectrum of seizure-related disorders,ranging from a relatively mild form of febrile seizures to a more severe epileptic encephalopathy known as Dravet syndrome.Early diagnosis of SCN1A mutation-associated epilepsy can aid in appropriate choice of antiepileptic drugs for treatment and reduce adverse sequelae. |
