Pyridoxine-dependent epilepsy (PDE) is a rare genetic disorder characterized by intractable seizures in the prenatal and neonatal period.

[1][2] The ALDH7A1 gene encodes for the enzyme antiquitin or α-aminoadipic semialdehyde dehydrogenase, which is involved with the catabolism of lysine.

[1][2] Despite remission of seizure activity with vitamin B6 supplementation, intellectual disability is frequently seen in patients with PDE.

Studies have been published which demonstrate potential for improved biomarkers, development, and behavior in patients treated with lysine restriction in addition to pyridoxine supplementation.

Plasma and cerebrospinal fluid levels of pipecolic acid are frequently elevated in patients with PDE, though it is a non-specific biomarker.