Thelansis

  Pyridoxamine-5'-phosphate oxidase (PNPO) deficiency is an autosomal recessive disorder characterized by impaired metabolism of pyridoxal 5'-phosphate (PLP), a crucial form of vitamin B6 essential for the function of various enzymes in the body. This deficiency manifests as a pyridoxal 5'-phosphate-responsive epileptic encephalopathy, with refractory seizures emerging typically within the first year of life. Prematurity, fetal distress, and neonatal seizures are commonly associated features. The phenotype of PNPO deficiency encompasses a spectrum of seizure types, with approximately 90% of affected individuals experiencing "classic" onset, marked by seizures in the neonatal period, and the remaining 10% exhibiting "late onset" seizures. Seizures, including status epilepticus, often commence within the first day of life in classic cases and before two weeks of age in the majority of instances. Despite variations in onset time, seizures typically exhibi...