Study on clinical and genetic characteristics of PCDH19 gene mutation related epilepsy / 中华实用儿科临床杂志

ABSTRACT

Objective:To retrospectively analyze the clinical and genetic features of PCDH19 gene mutation related epilepsy in 11 families. Methods:The clinical manifestations and genetic mutation characteristics of 13 children (from 11 families) diagnosed with PCDH19 gene mutation related epilepsy at the Department of Pediatric Neurology, the Third Affiliated Hospital of Zhengzhou University from March 2013 to July 2019 were analyzed. Results:(1) The results of PCDH19 gene mutations among 11 probands, 10 children had point mutations of PCDH19 gene and one child was with Exon 5 deletion.One male patient was detected with mosaic PCDH19 mutation, which was c. 840C > A, and the proportion of variation was 34.27%.Five hereditary and 6 de novo mutations were identified in 11 probands.Three patients inherited mutations from their clinically asymptomatic fathers with hemizygous mutation.Two patients inherited from their mothers, 1 case was diagnosed with epilepsy and the other was asymptomatic carrier.(2) Clinical features there were 12 females and 1 male in the enrolled 13 children, with the age of onset of less than 2 years old.The clinical phenotypes epilepsy with mental retardation in 9 patients, which including 3 patients with Dravet syndrome, and the remaining 4 patients were epilepsy without mental retardation.The phenotypic heterogeneity was observed in females with identical mutations from the same family, and a few girls can be asymptomatic.In all patients, seizures in clusters were observed in all 13 cases, fever sensitivity in 12 cases, and status epilepticus was only found in 3 cases.Of all the patients, only 2 cases had no seizures for more than 2 years, 3 cases with Dravet syndrome were given 6 to 8 kinds of antiepileptic drugs successively, but there were still frequent seizures. Conclusions:Most patients with PCDH19 mutations-related epilepsy are females, while rare mosaic males can be affected, phenotypic heterogeneity is obvious.Seizures in clusters and fever sensitivity are the major clinical features, and most patients are companied with different levels of intellectual impairment.Mutations in PCDH19 can be inherited or de novo, most of which are point mutations.