Neurometabolic Disorders-Related Early Childhood Epilepsy: A Single-Center Experience in Saudi Arabia

Abstract

BackgroundData on the pattern of epilepsy caused by metabolic disorders in the first 2 years of life are limited in developing countries. We aimed to identify the metabolic causes of epilepsy presented in the first 2 years of life and to describe their clinical, radiological, molecular, and electroencephalographic characteristics.MethodsThis retrospective study was conducted between January 2010 and December 2011 at Saad Specialist Hospital (Al Khobar, Saudi Arabia). All patients younger than 2 years at the onset of epilepsy caused by metabolic disorders were reviewed. The International League Against Epilepsy definition was used, and febrile convulsion was excluded.ResultsOf 221 children diagnosed with epilepsy in the first 2 years of life at our hospital, 24 had metabolic diseases. The characteristics of these 24 children included the following: consanguinity in 18 patients (75%), developmental delay in 13 (54%), generalized tonic–clonic seizures in 10 (42%), infantile spasms in four (17%), myoclonic in seven (29%), and focal seizures in three. The diagnosis was confirmed by DNA studies in 17 patients (71%) and enzyme assay in seven (29%). The main diagnoses were peroxisomal disorders (n = 3), nonketotic hyperglycinemia (n = 3), Menkes disease (n = 2), neuronal ceroid lipofuscinosis (n = 2), biotinidase deficiency (n = 2), and mitochondrial disorder (n = 2). The remaining patients had lysosomal storage disease, aminoacidopathy, fatty acid oxidation defects, and organic aciduria. Seizure freedom was achieved in one third of patients in this cohort.ConclusionDifferent metabolic disorders were identified in this cohort, which caused different types of epilepsy, especially myoclonic seizures and infantile spasms. Data on the pattern of epilepsy caused by metabolic disorders in the first 2 years of life are limited in developing countries. We aimed to identify the metabolic causes of epilepsy presented in the first 2 years of life and to describe their clinical, radiological, molecular, and electroencephalographic characteristics. This retrospective study was conducted between January 2010 and December 2011 at Saad Specialist Hospital (Al Khobar, Saudi Arabia). All patients younger than 2 years at the onset of epilepsy caused by metabolic disorders were reviewed. The International League Against Epilepsy definition was used, and febrile convulsion was excluded. Of 221 children diagnosed with epilepsy in the first 2 years of life at our hospital, 24 had metabolic diseases. The characteristics of these 24 children included the following: consanguinity in 18 patients (75%), developmental delay in 13 (54%), generalized tonic–clonic seizures in 10 (42%), infantile spasms in four (17%), myoclonic in seven (29%), and focal seizures in three. The diagnosis was confirmed by DNA studies in 17 patients (71%) and enzyme assay in seven (29%). The main diagnoses were peroxisomal disorders (n = 3), nonketotic hyperglycinemia (n = 3), Menkes disease (n = 2), neuronal ceroid lipofuscinosis (n = 2), biotinidase deficiency (n = 2), and mitochondrial disorder (n = 2). The remaining patients had lysosomal storage disease, aminoacidopathy, fatty acid oxidation defects, and organic aciduria. Seizure freedom was achieved in one third of patients in this cohort. Different metabolic disorders were identified in this cohort, which caused different types of epilepsy, especially myoclonic seizures and infantile spasms.