[Analysis of clinical phenotypes and genotypic characteristics in children with epilepsy]

To investigate the clinical phenotypes and genetic variant characteristics in children with epilepsy.

A total of 91 children with epilepsy admitted to the Women's and Children's Hospital Affiliated to Ningbo University from July 2021 to October 2022 were selected as the study subjects. Peripheral blood samples were collected from the children for whole exome sequencing. Candidate genetic variants were validated by Sanger sequencing and copy number variation sequencing (CNV-seq). The clinical phenotypes and treatment outcomes of the children with epilepsy were followed up, and an analysis of the relationship between genotype and phenotype was conducted. This study was approved by the Women's and Children's Hospital Affiliated to Ningbo University (Ethics No.: EC2020-048).

Among the 91 children with epilepsy, 21 cases (23.08%, 21/91) were found to carry pathogenic or likely pathogenic variants. Of these, 18 cases had involved single base variant or insertional deletion, while 3 cases involved copy number variations. The gene with the highest detection rate was PRRT2 (38.10%, 8/21). Among the children with genetic variants, 47.62% (10/21) had onset during infancy, with 8 diagnosed with Benign familial infantile epilepsy (BFIE), 8 with Developmental epileptic encephalopathy (DEE), and 3 with Epileptic encephalopathy (EE). One case of Dravet syndrome (DS) and one case of Infantile spasms (IS) were also noted. The clinical manifestations of children were diverse and primarily included generalized tonic-clonic seizures and focal seizures. Among them, 52.38% (11/21) had exhibited cluster seizures, 23.81% (5/21) showed fever sensitivity, and 14.29% (3/21) experienced status epilepticus. After pharmacological treatment, 42.86% (9/21) of children had achieved complete seizure control, while 61.90% (13/21) had intellectual disability and 19.05% (4/21) had co-morbid autism spectrum disorder.

Pathogenic or likely pathogenic variants were identified in 23.08% of the pediatric epilepsy cases, with the PRRT2 gene being the most frequently involved. Among children carrying genetic variants, 47.62% had seizure onset during infancy. Genetic factors are an important cause of epilepsy, and early genetic testing may facilitate precise diagnosis, treatment, and prognostic evaluation.