title: Pyridox(am)ine-5-Phosphate Oxidase Deficiency Treatable Cause of Neonatal Epileptic Encephalopathy With Burst Suppression: Case Report and Review of the Literature.
abstract: Pyridox(am)ine-5-phosphate oxidase deficiency is an autosomal recessive disorder of pyridoxine metabolism. Intractable neonatal epileptic encephalopathy is the classical presentation. Pyridoxal-5-phosphate or pyridoxine supplementation improves symptoms. We report a patient with myoclonic and tonic seizures at the age of 1 hour. Pyridoxal-5-phosphate was started on the first day of life and seizures stopped at the age of 3 days, but encephalopathy persisted for 4 weeks. She had normal neurodevelopmental outcome at the age of 12 months on pyridoxal-5-phosphate monotherapy. She had novel homozygous pathogenic frameshift mutation (c.448_451del;p.Pro150Argfs*27) in the PNPO gene. Long-lasting encephalopathy despite well-controlled clinical seizures does neither confirm nor exclude pyridox(am)ine-5-phosphate oxidase deficiency. Normal neurodevelopmental outcome of our patient emphasizes the importance of pyridoxal-5-phosphate treatment. Pyridox(am)ine-5-phosphate oxidase deficiency should be included in the differential diagnosis of Ohtahara syndrome and neonatal myoclonic encephalopathy as a treatable underlying cause. In addition, we reviewed the literature for pyridox(am)ine-5-phosphate oxidase deficiency and summarized herein all confirmed cases.
authors.affiliation: Division of Clinical and Metabolic Genetics, Department of Pediatrics, University of Toronto, Toronto, Canada.
authors.forename: Andrea
authors.initials: A
authors.lastname: Guerin
authors.affiliation: Division of Neurology, Department of Pediatrics, University of Toronto, The Hospital for Sick Children, Toronto, Ontario, Canada.
authors.forename: Aly S
authors.initials: AS
authors.lastname: Aziz
authors.affiliation: Occupational Therapy, Department of Rehabilitation Services, University of Toronto, The Hospital for Sick Children, Toronto, Ontario, Canada.
authors.forename: Carly
authors.initials: C
authors.lastname: Mutch
authors.affiliation: Division of Neonatology, Department of Pediatrics, University of Toronto, Toronto, Ontario, Canada.
authors.forename: Jillian
authors.initials: J
authors.lastname: Lewis
authors.affiliation: Division of Neurology, Department of Pediatrics, University of Toronto, The Hospital for Sick Children, Toronto, Ontario, Canada.
authors.forename: Cristina Y
authors.initials: CY
authors.lastname: Go
authors.affiliation: Division of Clinical and Metabolic Genetics, Department of Pediatrics, University of Toronto, Toronto, Canada Genetics and Genome Biology Program, Research Institute, The Hospital for Sick Children, Toronto, Canada saadet.mahmutoglu@sickkids.ca.
authors.forename: Saadet
authors.initials: S
authors.lastname: Mercimek-Mahmutoglu
mesh_terms: D001928:Brain Diseases, Metabolic / Q000150:complications* / Q000628:therapy*; D004569:Electroencephalography; D005260:Female; D006801:Humans; D020925:Hypoxia-Ischemia, Brain / Q000150:complications* / Q000628:therapy*; D007223:Infant; D039781:PubMed / Q000706:statistics & numerical data; D011734:Pyridoxaminephosphate Oxidase / Q000172:deficiency*; D012640:Seizures / Q000150:complications* / Q000628:therapy*; D013036:Spasms, Infantile / Q000209:etiology*
chemical_list: D011734:Pyridoxaminephosphate Oxidase
keywords: Ohtahara syndrome; neonatal epilepsy; neonatal myoclonic encephalopathy; pyridox(am)ine-5-phosphate oxidase; pyridoxal-5-phosphate