Since the publication of the initial case report in 1954 (1), seizures due to pyridoxine-dependency have been recognized as an uncommon cause of intractable seizures in neonates and infants. In the more than five decades since the first description of pyridoxine-dependent seizures (PDS, also known as pyridoxine-dependent epilepsy), more than 200 cases have been reported, with the majority of these publications appearing over the past 25 years focusing on atypical clinical presentations (2-5), neurodevelopmental features (6-9), electroencephalographic (EEG) characteristics (10-15), and imaging findings (6, 14, 16). The most recent reports have focused on the biochemical abnormality underlying pyridoxine-dependent seizures and the associated mutations in the ALDH7A1 gene (8, 17-25).
While neonatal seizures due to pyridoxine-dependency are felt to be quite rare, the reports of the late-onset and other atypical presentations (2-5) along with epidemiologic data from Europe (6, 26-28) suggest that this is a more common clinical entity than once thought.
In order to learn more about the variety of clinical presentations of PDS, the response of the disorder to various dosage regimens of pyridoxine, the imaging and EEG characteristics of the disorder, and the long term developmental consequences of PDS, we have developed a PDS Registry. Patients with PDS will be identified to the registry by physicians or parents. After informed consent, clinical and developmental data will be obtained and saved for future analysis and reporting. Other investigators interested in PDS may request to contact registered patients. These investigators will need to have a protocol approved by their institution’s "IRB". However, to protect confidentiality, outside investigators will not be able to directly contact registered patients. Parents who are interested in participating in other studies will be given the names of these researchers and the parents then may contact the investigators.
The PDS Registry was first developed by the Child Neurology Service at University of California, Davis Medical Center and is now administered by the Division of Pediatric Neurology at Children’s Hospital and Regional Medical Center and the University of Washington in Seattle.
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