Pyridoxine (vitamin B 6) (2q31) dependency is a rare autosomalrecessive disorder that causes a severe seizure disorder of prenatal or neonatal onset. The abnormality appears to inhibit the binding of vitamin B6 to the enzyme glutamic acid decarboxylase-1, which is needed for the biosynthesis of γ-aminobutyric acid (GABA). Most patients with pyridoxine-dependent seizures require lifelong treatment with pyridoxine. The full range of associated symptomatology is unknown since fewer than 100 cases have been reported. A majority of cases are mentally retarded. We report a 15-year-old boy with pyridoxine-dependent seizures, nonpyridoxine-dependent seizures, severe mental retardation, autistic disorder, aerophagia, breath holding, and self-injury. This complex outcome should alert clinicians to the wide range of neuropsychiatric outcomes associated with this disorder. (J Child Neurol 2000;15: 763-765).
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References
1.
Hunt AD, Stokes J., McCrory WW: Pyridoxine dependency: Report of a case of intractable convulsions in an infant controlled by pyridoxine. Pediatrics1954;13:140-145.
2.
Gospe SM: Current perspectives on pyridoxine-dependent seizures. JPediatr1998;132:919-923.
3.
Baxter P., Griffiths P., Kelly T., et al: Pyridoxine dependent seizures. Demographic, clinical radiological and psychometric features. Effect of dose on IQ. Dev Med Child Neurol1996;39:998-1006.
4.
Haenggeli CA , Girardin E., Paunier L.: Pyridoxine-dependent seizures, clinical and therapeutic aspects. Eur J Pediatr1991;150:452-455.
5.
Bejsovec M., Kulenda Z., Ponca E.: Familial intrauterine convulsions in pyridoxine dependency. Arch Dis Child1967;42:201-207.
6.
Osiovich H., Barrington K.: Prenatal ultrasound diagnosis of seizures. Am J Perinatol1996;8:499-500.
7.
Nabbout R., Soufflet C., Plouin P.: Pyridoxine dependent epilepsy: A suggestive electroclinical pattern . Arch Dis Child Fetal Neonatal Ed1999;81:F125-F129.
Goutieres F. , Aicardi J.: Atypical presentation of pyridoxine dependent seizures: A treatable cause of intractable epilepsy in infants. Ann. Neurol1984;17:117-120.
10.
Jardim LB, Pires RF, Martins CES, et al: Pyridoxine dependent seizures associated with white matter abnormalities . Neuropediatrics1994;25: 259-261.
11.
Bu DF, Erlander MG, Hitz BC, et al: Two human glutamate decarboxylases, 65-kDa GAD and 67-kDa GAD, are each encoded by a single gene. Proc Natl Acad Sci USA1992;89:2115-2119.
12.
McKusick VA: Mendelian Inheritance in Man, 12th ed. Baltimore, Johns Hopkins University Press, 1998.
13.
Scriver CR, Whelan DT: Glutamic acid decarboxylase (GAD) in mammalian tissue outside the central nervous system, and its possible relevance to hereditary vitamin B6 dependency with seizures. Ann N Y Acad Sci1969;166:83-96.
14.
Scriver CR, Perry TL: Pyridoxine dependency, in Scriver CR, Beaudet AL, Shy WS, et al (eds): The Metabolic Basis of Inherited Disease , 6th ed. New York, McGraw Hill, 1989, 764.
15.
Yoshida T., Tada K., Arakawa T.: Vitamin B6-dependency of glutamic acid decarboxylase in the kidney from a patient with vitamin B6 dependent convulsions. Tohoku J Exp Med1971;104:195-198.
16.
Gerster H.: The importance of vitamin B-6 in infant development. Evidence from human and animal studies. Z Ernahrungswiss1996;35: 309-317.
17.
Ebinger M., Schultze C., König S.: Demographics and diagnosis of pyridoxine-dependent seizures, abstract . J Pediatr1999;134:795.
18.
Baxter P.: Epidemiology of pyridoxine dependent and pyridoxine responsive seizures in the UK. Arch Dis Child1992;81:431-433.
19.
Pettit RE: Pyridoxine dependency seizures: Report of a case with unusual features . J Child Neurol1987;2:38-40.
20.
Martineau J. , Barthelemy C., Cheliakine C., et al: Brief report: An open middle-term study of combined vitamin B6-magnesium in a subgroup of autistic children selected on their sensitivity to this treatment. J Autism Dev Disord1988;18:435-447.
21.
Schaumburg H., Kaplan J., Windebank A., et al: Sensory neuropathy from pyridoxine abuse. A new megavitamin syndrome. N Engl JMed1983; 309:445-448.
22.
Mori K., Kaido M., Fujishiro K., et al: Effects of megadoses of pyridoxine on spermatogenesis and male reproductive organs in rats. Arch Toxicol1992;66:198-203.
23.
Tsutsumi S. , Tanaka T., Gotoh K., et al: Effects of pyridoxine on male fertility . J Toxicol Sci1995;20:351-365.
24.
McLachlan RS , Brown WF: Pyridoxine dependent epilepsy with iatrogenic sensory neuropathy. Can J Neurol Sci1995;22:50-51.
25.
Bessey OA, Adam DJD, Hansen AE: Intake of vitamin B6 and infantile convulsions: A first approximation of requirements of pyridoxine in infants. Pediatrics1957;20:33-44.
26.
Bower BD: Pyridoxine, tryptophan and epilepsy. Med Child Neurol1965;7:73-74.
27.
Coursin DB: Vitamin B6 deficiency in infants. AMA J Dis Child1955; 90:344- 348.
28.
Minns R.: Vitamin B6 deficiency and dependency. Dev Med Child Neurol1980;22:795-799.
29.
Scriver CR, Cullen AM: Urinary vitamin B6 and 4-pyridoxic acid in health and in vitamin B6 dependency . Pediatrics1965;36:14-20.
30.
Rimland B.: Controversies in the treatment of autistic children: Vitamin and drug therapy . J Child Neurol1988;3:S68-S72.
31.
Rimland B.: High dose vitamin B6 and magnesium in treating autism: Response to a study by Findling et al. J Autism Dev Disord1998 ;28: 581-582.
32.
American Academy of Pediatrics Committee on Nutrition: Megavitamin therapy for childhood psychoses and learning disabilities. Pediatrics1976 ;58:910-912.
33.
Findling RL , Maxwell K., Scotese-Wojtila L., et al: High-dose pyridoxine and magnesium administration in children with autistic disorder: An absence of salutary effects in a double-blind placebo controlled study. J Autism Dev Disord1997;27:467-478.
