From 1999 to 2007, 63 cases, ranging in age from 11 months to 40 years, were registered. Seventy percent of the cases presented with neonatal seizures, and the mean lag time between presentation and diagnosis was 313 days. Pyridoxine treatment regimens were varied ranging from 50 to 2500 mg per day (1.4 to 67.8 mg/kg/day). While 47 of the cases were seizure-free on pyridoxine monotherapy, over time eight other cases also required the concomitant use of anticonvulsants for effective seizure control, while the remainder continued to have recurrent seizures despite the use of pyridoxine and multiple anticonvulsants. Our review of this collection of cases suggests that for some registered individuals either pyridoxine may be acting as an adjunctive anticonvulsant, or the patient may have developed a secondary etiology for seizures. In addition, some of these cases may have pyridoxine-responsive seizures rather than pyridoxine-dependency. Four adult and seven school-aged cases were described as developmentally normal, while the other cases had a variety of neurodevelopmental handicaps. Twenty-five percent of the cases required pharmacologic treatment of behavioral symptoms.
For a complete description of the findings of this study, please see:
Basura GJ, Hagland SP, Wiltse AM, Gospe SM Jr: Clinical features and the management of pyridoxine-dependent and pyridoxine-responsive seizures: review of 63 North American cases submitted to a patient registry. Eur J Pediatr. 2009;168:697-704 . Abstract