In this article, we will provide information after studying hereditary metabolic diseases (HMD) where epilepsy manifests prominently. In the process of analyzing the database, we identified IMD associated with various types of epilepsy, which we classified according to the IMD classification based on classical pathophysiology and classified according to the factors associated with the selected seizure (neonatal seizures, infantile spasms, myoclonic seizures, and characteristic EEG patterns) and the possibility of treating the underlying metabolic defect. In addition, we analyzed the clinical severity level to compare the phenotype with biochemical characteristics, genotype, and delayed initiation of pyridoxine. As a result, we classified according to the clinical severity scale as follows: 1) global developmental delay/intellectual disability; 2) age of seizure onset before pyridoxine treatment; 3) current seizures during treatment. An expanded list of IMD, an overview of the main clinical signs, and the recommended diagnostic and therapeutic approaches may be useful for epileptologists and healthcare professionals assisting patients with metabolic disorders.

Seizures, Epilepsy, Metabolic, Drug-resistant epilepsy, Neurometabolic, Diagnosis, Treatment.

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