Compound heterozygosity with PRRT2: Pushing the phenotypic envelope in genetic epilepsies

Christelle Moufawad El Achkar; Beth Rosen Sheidley; Declan O'Rourke; Masanori Takeoka; Annapurna Poduri

doi:10.1016/j.ebcr.2016.12.001

Compound heterozygosity with PRRT2: Pushing the phenotypic envelope in genetic epilepsies

Epilepsy Behav Case Rep. 2017 Feb 1:11:125-128. doi: 10.1016/j.ebcr.2016.12.001. eCollection 2019.

Authors

Christelle Moufawad El Achkar¹, Beth Rosen Sheidley¹, Declan O'Rourke², Masanori Takeoka², Annapurna Poduri¹

Affiliations

¹ Epilepsy Genetics Program, Division of Epilepsy and Clinical Neurophysiology, Department of Neurology, Boston Children's Hospital, and Harvard Medical School, Boston, MA 02115, United States.
² Division of Epilepsy and Clinical Neurophysiology, Department of Neurology, Boston Children's Hospital, and Harvard Medical School, Boston, MA 02115, United States.

Abstract

PRRT2 pathogenic variants have been described in benign familial infantile epilepsy, episodic ataxia, paroxysmal kinesigenic dyskinesia, and hemiplegic migraines. We describe a patient with compound heterozygous variants, infantile epilepsy with status epilepticus, paroxysmal dyskinesia and episodic ataxia. Testing revealed a pathogenic PRRT2 duplication (c.649dupC), and a likely pathogenic missense variant (c.916G>A). His presentation meets the severe phenotypic category with a combination of at least 3 neurological symptoms: seizures and status epilepticus, prolonged episodic ataxia, and paroxysmal dyskinesia. This further expands the clinical findings related to PRRT2, and suggests that compound heterozygous variants could confer a severe phenotype.

Keywords: Ataxia; Epilepsy; Genetic epilepsies; Kinesigenic dyskinesia; PRRT2.

Publication types

Case Reports