Use

CSF Alpha aminoadipic semialdehyde is useful for diagnosing pyridoxine-dependent seizures (PDS) and folinic acid-responsive seizures (FRS). This testing may also be used for assessment of Variants of Uncertain Significance (VUS) identified during genetic testing (e.g. Next Generation Sequencing or Capillary Sequencing testing). Pyridoxine dependent seizures is a genetic disorder characterized by seizures in neonates or infants up to 3 years of age, which in general, respond to a pharmacologic dose of pyridoxine (vitamin B6). Alpha - aminoadipic semialdehyde dehydrogenase (antiquin) deficiency is the underlying defect. Piperideine-6- Carboxylate (P6C) is the cyclic isomer of alpha aminoadipic semialdehyde (AASA) and the equilibrium between P6C and Alpha aminoadipic semialdehyde is pH dependent. Folinic responsive seizures and PDS are allelic, and caused by mutations in the ALDH7A1 gene. Biochemical testing should be done prior to gene sequencing, and can be done regardless of pyridoxine therapy.