Pyridoxine-dependent seizures: a family phenotype that leads to severe cognitive deficits, regardless of treatment regime
Article first published online: 19 MAR 2007
Developmental Medicine & Child Neurology
Volume 49, Issue 4, pages 300–305, April 2007
How to Cite
Rankin, P. M., Harrison, S., Chong, W. K., Boyd, S. and Aylett, S. E. (2007), Pyridoxine-dependent seizures: a family phenotype that leads to severe cognitive deficits, regardless of treatment regime. Developmental Medicine & Child Neurology, 49: 300–305. doi: 10.1111/j.1469-8749.2007.00300.x
- Issue published online: 19 MAR 2007
- Article first published online: 19 MAR 2007
- Accepted for publication 26th October 2006.
The neuropsychological and clinical histories of three male siblings affected by pyridoxine-dependent seizures with known homozygous antiquitin mutations are presented. Neuropsychological evaluation is reported from when the siblings were 11, 9, and 7 years of age. Two of the siblings had received early pyridoxine treatment (antenatal, 2–4wks into pregnancy) and one had received late treatment (2mo postnatal). However, there was no differential effect on cognitive outcome, with all three siblings having moderate to severe learning disability. Unlike previously reported cases that received early postnatal treatment, none of the siblings had relatively preserved non-verbal cognitive skills. Equally, their intellectual performance over time did not increase above the 1st centile despite high maintenance doses of vitamin B6 (range 16–26mg/kg/d), and mild sensory neuropathy was reported on nerve conduction studies. The findings in these siblings challenge assumptions that early and high dose pyridoxine treatment can benefit cognition in this population and suggest routine electromyography monitoring may be beneficial.