An infant with pyridoxine-dependent seizures and MRI, PET, and EEG evidence of diffuse structural or functional brain disease is reported from the University of New Mexico Health Sciences Center, Albuquerque, NM, and the UCLA School of Medicine, Los Angeles, CA. Seizures began at 10 weeks, and status epilepticus occurred four times between 3 and 7 months of age. Trials of AEDs and ACTH were partially effective, but he became encephalopathic and hypotonic. EEG showed diffuse slowing with right posterior epileptiform discharges. A PET scan showed global cortical hypometabolism. Continued on phenobarbital monotherapy, he presented at 10 months with status and respiratory compromise. IV pyridoxine, 100 mg, controlled the seizure within 4 minutes, he was extubated after 1 day, and was maintained on 50 mg pyridoxine daily. Phenobarbital was tapered without relapse. He gradually recovered muscle tone, walked at 15 months, and was seizure-free at 20 months, but speech was delayed. MRI showed diffuse cortical atrophy, especially frontal. 
COMMENT. Pyridoxine-dependent seizures may be complicated by structural and functional brain disease. These abnormalities demonstrated by MRI and PET may result from the metabolic dysfunction secondary to pyridoxine-dependency, but the effects of hypoxia with repeated episodes of status epilepticus and possibly the use of ACTH in treatment of the seizures could have contributed to the cerebral atrophy demonstrated by MRI. The remarkable clinical recovery of this patient, after the diagnosis was made and specific treatment initiated at 10 months, emphasizes the importance of a trial of pyridoxine for intractable epilepsy, even in older infants and children.