- Pyridoxine dependency
- Pyridoxine dependency with seizures
- Vitamin B6-dependent seizures
Your QuestionMy daughter was diagnosed with pyridoxine-dependent epilepsy at birth. Her symptoms were controlled until a few years ago when she began to have muscle stiffness in the hands and legs, partial seizures, and loss of her voice. Her seizures now occur almost daily and are quite violent. Her doctors believe that her seizure activity may now be the result of psychogenic nonepileptic seizures (PNES). Is this a common occurrence in adults with pyridoxine-dependent epilepsy?
We have identified the following information that we hope you find helpful. If you still have questions, please contact us.
Questions on this page
- What is pyridoxine-dependent epilepsy?
- What symptoms are associated with pyridoxine-dependent epilepsy?
- What causes pyridoxine-dependent epilepsy?
- How might pyridoxine-dependent epilepsy be treated?
- What are psychogenic nonepileptic seizures?
- Are you aware of any other individuals with pyridoxine-dependent epilepsy who have developed psychogenic nonepileptic seizures in adulthood?
Mutations in the ALDH7A1 gene cause pyridoxine-dependent epilepsy. This condition is inherited in an autosomal recessive pattern, which means both copies of the gene in each cell have mutations. The parents of an individual with an autosomal recessive condition each carry one copy of the mutated gene, but they typically do not show signs and symptoms of the condition.
The ALDH7A1 gene provides instructions for making an enzyme called α-aminoadipic semialdehyde (α-AASA) dehydrogenase, also known as antiquitin. This enzyme is involved in the breakdown of the protein building block (amino acid) lysine in the brain.
When antiquitin is deficient, a molecule that interferes with vitamin B6 function builds up in various tissues. Pyridoxine plays a role in many processes in the body, such as the breakdown of amino acids and the productions of chemicals that transmit signals in the brain (neurotransmitters). It is unclear how a lack of pyridoxine causes the seizures that are characteristic of this condition.
Some individuals with pyridoxine-dependent epilepsy do not have identified mutations in the ALDH7A1 gene. In these cases, the cause of the condition is unknown.
You can read more about this type of seizure at the following link from the Epilepsy Foundation. For additional information, contact the Women and Epilepsy Initiative of the Epilepsy Foundation at (800) 332-4050.
After an extensive search of the resources available to us, we have not been able to identify any reports which discuss individuals with pyridoxine-dependent epilepsy who have developed psychogenic nonepileptic seizures in adulthood.
You may wish to contact the following organizations which deal specifically with epilepsy to see if they are aware of any such cases. These groups may also be able to recommend a specialist who can assist your daughter in control of her symptoms.
8301 Professional Place
East Landover, MD 20785-2238
Toll-free: 800-EFA-1000 (800-332-1000)
American Epilepsy Society
342 North Main Street
West Hartford CT 06117-2507
- Pyridoxine-dependent epilepsy. Genetics Home Reference (GHR). 2013; http://ghr.nlm.nih.gov/condition=pyridoxinedependentepilepsy. Accessed 7/23/2013.
- Gospe SM. Pyridoxine-Dependent Seizures. GeneReviews. 2012; http://www.ncbi.nlm.nih.gov/books/NBK1486/. Accessed 7/23/2013.
- van Karnebeek CD et al. Lysine restricted diet for pyridoxine-dependent epilepsy: first evidence and future trials. Mol Genet Metab. 2012 Nov;107(3):335-44. .
- Nonepileptic Seizures. Epilepsy Foundation. http://www.epilepsyfoundation.org/answerplace/Life/adults/women/Professional/nonepileptic.cfm. Accessed 5/26/2009.