Late-onset Vitamin B6-dependent epilepsy caused by compound heterozygous pathogenic PLPBP variants

Evidence has shown that pathogenic variants of the PLPBP gene can cause vitamin B6-dependent epilepsy, a condition characterized by neonatal-onset seizures that respond to vitamin B6 supplementation. In this paper, we report a case of vitamin B6-dependent epilepsy in a Japanese girl caused by compound heterozygous variants in PLPBP, NM_007198.4: c.275A > G (p. H92R) (novel)/c.319G > A (p. A107T) (reported), which developed when the patient was just 8 months old but was diagnosed at 10 years of age. Even after the neonatal period, vitamin B6-dependent epilepsy should be considered as a differential diagnosis of refractory epilepsy, with genetic analysis being useful for its diagnosis and treatment.