ABSTRACT
Objective:To study the genetic profiles and clinical characteristics of neonatal-onset genetic epilepsy.Methods:From July 2016 to May 2021, patients with neonatal-onset genetic epilepsy admitted to our hospital and received second-generation genetic sequencing were enrolled in this study. According to the types of genetic variations, the patients were assigned into ion channel group and non-ion channel group. Clinical characteristics, treatments and prognosis of the two groups were compared.Results:A total of 36 patients with identified genetic variations were enrolled, involving 15 epilepsy-related genes. KCNQ2, SCN2A and STXBP1 were the most common pathogenic genes. 20 cases (55.6%) were in the ion channel group and 16 cases (44.4%) in the non-ion channel group. No significant differences existed in their general status, seizure types, EEG characteristics, treatments and outcomes between the two groups ( P>0.05). Among all 36 cases, the age of onset ranged from 10 min to 24 d after birth and 28 cases (78.8%) developed epilepsy within 1 week after birth. Developmental and epileptic encephalopathies were diagnosed in 20 patients. 7 patients were diagnosed with self-limited neonatal epilepsy, 2 were pyridoxine dependence, 2 were Zellweger syndrome and 1 case of self-limited familial neonatal-infantile epilepsy, Turner type mental retardation with epilepsy, PURA syndrome, Rett syndrome and 22q11.2 deletion syndrome, each. The patients received antiepileptic drugs including phenobarbital, levetiracetam, oxcarbazepine, topiramate, valproic acid, benzodiazepines (nizepam/clonazepam /clobazam/midazolam), lacosamide and lamotrigine. 5 patients died after giving up treatment. 31 patients were followed up for 6 to 50 months. 22 cases (71.0%) were controlled at 1- to 35-month-old including 21 cases (56.7%) with developmental delay. 6 cases (19.4%) had ineffective seizure control and 3 cases (9.7%) showed reduced seizures, all with varying degrees of developmental delay. Conclusions:Neonatal-onset epilepsy is correlated with multiple genes. KCNQ2, SCN2A, STXBP1 are the common pathogenic genes with multiple variants of KCNQ2 gene. Most patients have seizures within 1 week after birth. More than half of patients have ion channel related gene variations. Sodium channel blockers have certain effects as treatment.