title: [Pyridoxine dependence: the importance of the clinical diagnosis and early treatment].
abstract: OBJECTIVE
  We described the electroclinical features, evolution and family history of two patients with definitive diagnosis of pyridoxine dependency.
  
  
  METHODS
  The first patient is a 15-month-old girl who at 1 month of age started with seizures and irritability. At two months of age, pyridoxine was prescribed with a good control of seizures. At five months of age withdrawal response provoked 7 days after seizures recurrence. Pyridoxine was reintroduced and seizures disappeared. Her sister, at two months of age, started with refractory seizures. This sister also had mental retardation and at four years, she died. Her brother, 16 years old, presents mental retardation, refractory epilepsy and progressive motor and cognitive impairment. At 3 months of age, he started with seizures and at 15 years of age, pyridoxine was prescribed with a significative improvement the number of seizures and a better visual connection. The second patient is a 4-month-old girl who started with clonic seizures at 3 days of age and she had a good response to pyridoxine. Withdrawal response provoked seizure recurrence at 48 hours. Pyridoxine was introduced immediately with total control of seizures. She had two cousins with seizures who died at 3 months and 3 years of age respectively.
  
  
  CONCLUSIONS
  When dealing with an infant with refractory seizures which start in the first two years of life and without etiology, we should consider the diagnosis of pyridoxine dependency. Early diagnosis and treatment with pyridoxine is crucial to avoid high risk morbidity and mortality. All infants in the two first years of life with refractory seizures without etiology must be prescribed oral pyridoxine (50-200 mg per day).
authors.affiliation: Servicio de Neurología, Hospital de Niños Prof Dr JP Garrahan, Buenos Aires, Argentina. rcaraballo@janssen.com.ar
authors.forename: R
authors.initials: R
authors.lastname: Caraballo
authors.forename: F
authors.initials: F
authors.lastname: Garro
authors.forename: R
authors.initials: R
authors.lastname: Cersósimo
authors.forename: C
authors.initials: C
authors.lastname: Buompadre
authors.forename: L A
authors.initials: LA
authors.lastname: Gañez
authors.forename: N
authors.initials: N
authors.lastname: Fejerman
mesh_terms: D005260:Female; D006801:Humans; D007223:Infant; D011736:Pyridoxine / Q000502:physiology* / Q000627:therapeutic use; D012640:Seizures / Q000175:diagnosis / Q000188:drug therapy / Q000209:etiology*; D013997:Time Factors
chemical_list: D011736:Pyridoxine