A full-term female neonate developed focal motor seizures at 1 hour of life, followed by paroxysmal nonepileptic abnormal eye–head movements on day 5 (video 1). CSF revealed mild hypoglycorrhachia, borderline low CSF:serum glucose, and pyridoxal-5′-phosphate (P5P). Genetic testing showed compound heterozygous mutations in the pyridoxamine 5′-phosphate oxidase ( PNPO ) gene consistent with P5P-d...