Pyridoxine-Dependent Seizures Panel - Plasma

Clinical Use

Use

This test provides quantitative analysis of piperideine-6-carboxylate (P6C) and pipecolic acid in plasma. Pathogenic variants in ALDH7A1 are associated with pyridoxine-dependent epilepsy, which is characterized by prolonged seizures that can begin in infancy or, in some cases, prenatally. Affected individuals may also experience tonic-clonic seizures, dystonia, and hypothermia. Anticonvulsants are ineffective, necessitating treatment with pyridoxine supplementation. However, some patients may still experience developmental delays despite treatment. Elevated concentrations of P6C and pipecolic acid are indicative of pyridoxine-dependent epilepsy.

Special Instructions

This assay is specifically designed for the evaluation of pyridoxine-dependent epilepsy and is not suitable for carrier testing. Clinical consultation is recommended to interpret test results accurately. To aid in logistics, ensure that the specimen is drawn in a Sodium Heparin (green-top) tube and separated quickly for optimal analysis. Follow proper shipping and handling protocols to maintain specimen integrity during transit.

Limitations

This assay is primarily intended for individuals with a confirmed or suspected diagnosis of pyridoxine-dependent epilepsy. Testing is not appropriate for carrier screening as it does not provide a comprehensive analysis of all potential pathogenic variants nor does it effectively rule out the condition in families when negative. Additionally, assay performance may vary based on patient factors, which can affect the concentrations of the analytes measured.

Test Details