Teaching Video NeuroImages: Atypical Abnormal Eye Movements in PNPO -Related Epilepsy

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 low pyridoxal-5′-phosphate (P5P). Genetic testing showed compound heterozygous mutations in the pyridoxamine 5′-phosphate oxidase ( PNPO ) gene consistent with P5P-dependent epilepsy. Aberrant gaze saccades with head jerks are classically described in GLUT-1 deficiency,1 though not described in other conditions with associated hypoglycorrhachia. PNPO-associated epilepsy has been associated with abnormal eye movements2 and should be considered when neonates present with seizures and aberrant saccades with coordinated head movements.