Table 6.

Pyridoxine and pyridoxal-5′-phosphate-dependent Epilepsies.

	Pyridoxine- or folinic-acid-dependent epilepsies (PDE)	Pyridoxal-5′-phosphate (PLP-) dependent epilepsy
Deficient enzyme	Antiquitin (ATQ)	Pyridox(am)ine phosphate oxidase (PNPO)
Blood chemistry	Normal, but hypoglycemia and lactic acidosis have been reported	Hypoglycemia and lactic acidosis common
Vanillactic acid (Urine)	Absent	Present
Pipecolic acid (blood, CSF)	↑	Normal
AASA* (blood, urine, CSF)	↑	Normal
Neurotransmitter metabolites (CSF)	(Possible) ↑ 3-Methoxytyrosine	↑ L-DOPA, 3-Methoxytyrosine ↓ Homovanillic acid, 5-Hydroxyindoleacetic acid
Clinical signs	Postnatal refractory seizures, gastrointestinal symptoms, encephalopathy with hyperalertness, sleeplessness	Fetal distress and in utero fetal seizures, postnatal refractory seizures and encephalopathy

 *AASA: alpha-aminoadipic semialdehyde. Adapted from Pearl [2].