Screening Inherited Metabolic Disorder in Children with Intellectual Disability and Epilepsy

Objective: To indicate the benefits of the screening of inherited metabolic disorders in patients with epilepsy, global developmental delay, and intellectual disability. Materials and Methods: The medical records of 1100 patients who were investigated for inherited metabolic disorders between March 2014 and June 2017 were evaluated. Five hundred patients with epilepsy and global developmental delay/intellectual disability with mild/moderate and non-specific neurologic findings were enrolled in the study. Results: Inherited metabolic disorders were detected in 7 of 500 patients (1.4%) with epilepsy and global developmental delay/intellectual disability. One patient was diagnosed as having tyrosinemia type-2, one had Menkes disease, one had mitochondrial disease, one had hyperphenylalaninemia, two siblings were diagnosed as having 3-methylcrotonyl Coa carboxylase deficiency, and one patient was diagnosed as having phenylketonuria. Conclusion: The prevalence of inherited metabolic disorders is higher in countries with a high consanguinity ratio such as Turkey. Lack of the regular screening in patients with mild/moderate and non-specific neurologic findings result in late diagnosis.