P13 – 2298: PCDH19 related epileptic encephalopathy in a 9-year-old girl – Case report

Abstract

Introduction Mutation in PCDH 19 gene, encoding prothocadherin 19 on chromosome Xq22, results in an epileptic syndrome of seizure onset in infancy, mild to severe intellectual impairment with or without autistic features. This disorder demonstrates an unusual pattern of X-linked inheritance, affecting heterozygous female but sparing hemizygous male individuals. The underlying responsible mechanism is considered to be a “cellular interference”. There is a wide clinical spectrum of seizures, generally starting in infancy or early childhood. A portion of patients manifests a phenotype resembling a Dravet syndrome. The seizures mostly occur in brief clusters even at mild to moderately elevated temperature. In initial course of the disease the seizures become relatively resistant to antiepileptic drugs. However, as the disease progresses, the frequency of seizures and their pharmacoresistance tends to decrease. There may be behavioral difficulties such as autistic, obsessive or aggressive features. Objective is to show the clinical features of PCDH19 related epilepsy in a 9-year-old girl with a focus on early disease characteristics and treatment efficacy. Patient and methods A 9-year-old girl from early childhood suffering and treated of resistant epilepsy that was clinically presented with a series of focal motor seizures accompanied by fear and screaming. Repeated interictal waking and sleeping EEGs, as well as high resolution brain MRI (3T) was normal. Analysis of cerebrospinal fluid excluded inflammatory diseases of the CNS. The rare metabolic diseases with epileptic seizures were excluded by metabolic tests. After the first seizure phenobarbital was recommended, and after recurrence there was a therapy with multiple combinations of various antiepileptic drugs, none of which was effective. Further treatment included a genetic analysis which found mutation PCDH19Xq22.1. The therapy included perampanel with topiramate. Conclusion The authors have the intention to warn to this epileptic encephalopathy that affects only female children and emphasize its importance in the differential diagnosis of uncontrolled epileptic syndromes associated with febrile conditions.