Chromosomal microarray in unexplained severe early onset epilepsy - A single centre cohort.
BACKGROUND
Severe early onset epilepsy may lead to impaired cognitive and motor development, and consists of a group of specific and overlapping electro-clinical phenotypes which may be the result of an inborn error of metabolism, congenital or acquired structural brain lesion, known chromosomal or mono-genetic disorder. A significant proportion of cases however remain unexplained, representing a major diagnostic and management challenge.


METHODS
In this study we describe a cohort of children with severe early onset epilepsy and examine the clinical utility of chromosomal microarray (array-comparative genomic hybridisation, CGH) in this group of epilepsies.


RESULTS
In 51 children with unexplained severe early onset epilepsy, all of whom had chromosomal array tested, copy number variants were detected in 17.6% and pathogenic variants in 5.9% of infants.


CONCLUSIONS
Chromosomal microarray is a useful investigation in early onset refractory epilepsy and epileptic encephalopathy. Detailed review of the precise array abnormality and phenotypes associated are important for determining significance.
Department of Child Neurology & Clinical Neurophysiology, Children's University Hospital, Temple St., Dublin, Ireland. Electronic address: nickyallen79@hotmail.com.
Nicholas M
NM
Allen
Department of Genetics, Children's University Hospital, Temple St., Dublin, Ireland; Academic Center on Rare Diseases, School of Medicine and Medical Science, University College Dublin, Ireland.
Judith
J
Conroy
Department of Child Neurology & Clinical Neurophysiology, Children's University Hospital, Temple St., Dublin, Ireland.
Amre
A
Shahwan
Academic Center on Rare Diseases, School of Medicine and Medical Science, University College Dublin, Ireland.
Sean
S
Ennis
Department of Child Neurology & Clinical Neurophysiology, Children's University Hospital, Temple St., Dublin, Ireland.
Bryan
B
Lynch
Department of Genetics, Children's University Hospital, Temple St., Dublin, Ireland; Academic Center on Rare Diseases, School of Medicine and Medical Science, University College Dublin, Ireland.
Sally A
SA
Lynch
Department of Child Neurology & Clinical Neurophysiology, Children's University Hospital, Temple St., Dublin, Ireland; Academic Center on Rare Diseases, School of Medicine and Medical Science, University College Dublin, Ireland.
Mary D
MD
King
D001921:Brain / Q000473:pathology; D002648:Child; D055028:Comparative Genomic Hybridization; D056915:DNA Copy Number Variations; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D020411:Oligonucleotide Array Sequence Analysis; D010641:Phenotype; D013036:Spasms, Infantile / Q000235:genetics* / Q000473:pathology*
Epilepsy; Epileptic encephalopathy; Infantile spasms; West syndrome