Metabolic Diseases with Epilepsy Vitamin Responsive Conditions

Vitamin-responsive metabolic epilepsies are a group of inherited disorders characterized by a specific enzyme deficiency, and not a vitamin deficiency state. Epilepsy is usually present at disease onset, and most patients do not respond to antiepileptic drugs. However, personalized treatment with specific vitamin therapy markedly improves both seizures and encephalopathy.

Early diagnosis (molecular genetic testing and biochemical determination of specific biomarkers in blood, urine, and cerebrospinal fluid) and specific treatment are mandatory when these disorders are suspected as clearly impact in the clinical outcome.

We will describe the pathophysiology and clinical phenotype of vitamin-dependent disorders such as pyridoxine-dependent epilepsy (antiquitine deficiency, PROSC mutations), pyridoxal 5′-phosphate-dependent epilepsy (pyridoxamine 5′-phosphate oxidase deficiency), and biotinidase deficiency, and transportopathies such as cerebral folate deficiency and thiamine transporter-2 deficiency. We also describe the response to specific vitamin therapy of these disorders and their outcome.

No conflict of interest has been declared by the author(s).