Analysis of clinical characteristics and histopathological transcription in 40 patients afflicted by epilepsy stemming from focal cortical dysplasia

Abstract

ObjectiveThis study aims to comprehensively analyze the clinical characteristics and identify the differentially expressed genes associated with drug‐resistant epilepsy (DRE) in patients with focal cortical dysplasia (FCD).MethodsA retrospective investigation was conducted from July 2019 to June 2022, involving 40 pediatric cases of DRE linked to FCD. Subsequent follow‐ups were done to assess post‐surgical outcomes. Transcriptomic sequencing and quantitative reverse transcription polymerase chain reaction (qRT‐PCR) were used to examine differential gene expression between the FCD and control groups.ResultsAmong the 40 patients included in the study, focal to bilateral tonic–clonic seizures (13/40, 32.50%) and epileptic spasms (9/40, 22.50%) were the predominant seizure types. Magnetic resonance imaging (MRI) showed frequent involvement of the frontal (22/40, 55%) and temporal lobes (12/40, 30%). In cases with negative MRI results (13/13, 100%), positron emission tomography/computed tomography (PET‐CT) scans revealed hypometabolic lesions. Fused MRI/PET‐CT images demonstrated lesion reduction in 40.74% (11/27) of cases compared with PET‐CT alone, while 59.26% (16/27) yielded results consistent with PET‐CT findings. FCD type II was identified in 26 cases, and FCD type I in 13 cases. At the last follow‐up, 38 patients were prescribed an average of 1.27 ± 1.05 anti‐seizure medications (ASMs), with two patients discontinuing treatment. After a postoperative follow‐up period of 23.50 months, 75% (30/40) of patients achieved Engel class I outcome. Transcriptomic sequencing and qRT‐PCR analysis identified several genes primarily associated with cilia, including CFAP47, CFAP126, JHY, RSPH4A, and SPAG1.SignificanceThis study highlights focal to bilateral tonic–clonic seizures as the most common seizure type in patients with DRE due to FCD. Surgical intervention primarily targeted lesions in the frontal and temporal lobes. Patients with FCD‐related DRE showed a promising prognosis for seizure control post‐surgery. The identified genes, including CFAP47, CFAP126, JHY, RSPH4A, and SPAG1, could serve as potential biomarkers for FCD.Plain Language SummaryThis study aimed to comprehensively evaluate the clinical data of individuals affected by focal cortical dysplasia and analyze transcriptomic data from brain tissues. We found that focal to bilateral tonic–clonic seizures were the most prevalent seizure type in patients with drug‐resistant epilepsy. In cases treated surgically, the frontal and temporal lobes were the primary sites of the lesions. Moreover, patients with focal cortical dysplasia‐induced drug‐resistant epilepsy exhibited a favorable prognosis for seizure control after surgery. CFAP47, CFAP126, JHY, RSPH4A, and SPAG1 have emerged as potential pathogenic genes for the development of focal cortical dysplasia.