To explore clinical characteristics and prognosis of Na⁺ channel blockers in treatment of early-onset epileptic encephalopathy(EOEE) children caused by SCN2A gene variation.

One boy with EOEE diagnosed at Shenzhen Children′s Hospital on November 24, 2015, whose age was 4 months at the time of diagnosis, was selected into this study. The clinical features, genetic test results, therapeutic regimen and follow-up results of this boy were analyzed retrospectively. By searching relevant literature on research of children with EOEE caused by SCN2A gene variation in China National Knowledge Infrastructure, Wanfang database, and PubMed, their clinical data and genetic characteristics were summarized. The procedure followed in this study was in line with the requirements of the Helsinki Declaration of the World Medical Association revised in 2013. Informed consent for clinical research was obtain from guardians of this boy.

①This boy began to have repeated convulsive epileptic seizures on the third day after birth, showing tonic-clonic seizures, focal clonic seizures and spastic seizures, and complication of developmental retardation. The therapeutic effects of combination of various antiepileptic drugs were poor. ②The electroencephalogram results of this boy suggested burst suppression of anoxic epileptic encephalopathy; the genetic test showed a missense mutation in SCN2A gene with NM_001040143: c4886G>A(pArg1629His), and neither his father nor his mother showed any abnormality in SCN2A gene; result of head MRI of this boy suggested a right choroidal fissure cyst. ③ This boy was treated with oxcarbazepine up to his convulsive epileptic seizures had disppeared thoroughly. The electroencephalogram reexamination results showed there was still a small amount of epileptiform discharge, and his mental development gradually improved. ④ According to literature retrieval strategies set in this study, 4 Chinese and 7 English articles with a total of 44 EOEE children caused by SCN2A gene variants were published.

Genetic testing for EOEE children should be completed in time. After identifying pathogenic gene of EOEE, timely precise treatment of pathogenic gene for EOEE children can control convulsive epileptic seizure, reduce brain damage of EOEE children and improve their prognosis.