Specimen Collection
10 mL Urine (Random)Keep cool and freeze (-20
o
C) if not sent to the laboratory immediately.
Diagnostic Use and Interpretation
Alpha-aminoadipic semialdehyde (AASA) is the diagnostic marker for pyridoxine dependent epilepsy.
The disease is caused by enzyme defect in alpha-aminoadipic-semialdehyde dehydrogenase (encoded by
ALDH7A1
gene) in the lysine degradation pathway, leading to accumulation of AASA and piperideine 6-carboxylate (P6C). AASA is in chemical equilibrium with P6C.
Pyridoxine dependent epilepsy is characterized by early onset epileptic encephalopathy. The onset is typically in the neonatal period with intractable seizures, status epileptics that are poorly controlled by
pharmacological
anticonvulsants
but response to large dose of pyridoxine. Despite seizure control most patients have intellectual disability.
Contact Information
For further information contact laboratory: ext 22016 or via Lablink
or, contact the Metabolic Physician-on-call: 09 367 0000